Inland Seas Angler

              GREAT LAKES BASIN REPORTÓ

 

    A Publication of the Great Lakes Sport Fishing Council                                                                                         April 2004

                                  http://www.great-lakes.org                                                                                                                                         Vol. 15, No. 4


 

Highlights of the Great Lakes Fishery Commission's Lake Committee Meetings

Following are highlights of the Annual Lake Committee Meetings for Lakes Erie and Michigan for 2004. We will report on the Lake Committees of Huron, Michigan, Ontario and Lake St. Clair in upcoming issues of the Great Lakes Basin Report.

                The upper lake committee meetings — for Lakes Michigan, Huron and Superior— were held in Ann Arbor, MI, March 22-25. The lake committee meeting for Lakes Erie, Huron and Ontario was held in Grand Island, NY, March 29-April 1.
 

Lake Erie Fishery Review for 2003

 

2004 Catch Limits Set for Walleye & Perch

Yellow Perch Increased; Walleye Reduced with great '03 walleye/perch classes

GRAND ISLAND, NY – Lake Erie fishery managers from Michigan, New York, Ohio, Ontario and Pennsylvania agreed during the Lake Erie Committee's annual meeting to an 11% increase in the yellow perch catch limit and a 30% reduction in the walleye catch limit for the 2004 fishing season. Even so, the committee, meeting in Grand Island, NY on March 31, expressed optimism over the future of the fishery. It is anticipated that strong spawning success in 2003 in both the walleye and yellow perch fisheries will lead to improvements in 2005.

 

 

In this issue…

 

This issue highlights Great Lakes Fishery Commission Lake Committee Meetings for Lakes Erie and Michigan. It has been expanded 67% to 20 pages to report the latest data.

 

  Lake Erie.................... 1-2 & 3-11 

  Lake Michigan.............. 1 & 12-19 

  GLSFC Nominations................. 2 

 

 

 

Walleye

The lakewide total allowable catch of walleye will be reduced by 1 million fish, for a total allowable catch (TAC) in 2004 of 2.4 million fish. The Committee’s Walleye Task Group ― comprising scientists and field biologists ― reported that walleye spawning had been poor in 2000 and 2002, and, based on these reports, the committee recommended the 30% reduction in walleye limits in 2004. This reduction reflects the belief of the committee that the scarce two-year-old walleye population needs to be protected from over-harvest to

 

Lake Michigan Fishery Review for 2003

Recreational Fishery Summary

Total recreational fishing effort has been relatively stable since 1995 in the Southeast, Northwest, and Green Bay regions of Lake Michigan. Effort has been more variable in the Southwest region and over the last

maintain a balanced age structure in the lake. This protection is designed to help walleye rebuild. Actual harvest in 2003 was a 2.7 million fish.

                All agencies have been closely monitoring the status of walleye spawning during the previous years and have, until 2004, held harvest constant over the previous 3 years. Very strong walleye spawning in 2003 ― the best spawning in more than 20 years ― has generated optimism among the committee members that walleye survival and
Catch Limits Set

continued on page 2

few years there were roughly 50% fewer angling-hours than the peak levels of the mid 1980s. Targeted effort for yellow perch remains low in Green Bay; Wisconsin waters of  Green Bay recorded a new low of 108,000 yellow perch angling-hours.

Lake Trout: Lake trout harvest rates declined in all regions of the lake between 2001 and 2003. In 2003, less than 30,000 lake trout were harvested from Wisconsin, Indiana, and Illinois; this represents the second lowest harvest on record, only 2001 was lower. (Table 3)     
Recreational Fishery Summary

continued on page 13

 

N

ominations are open for all offi-cer and director positions of the GLSFC for the ’05-’06 term. Nomi-nations will be accepted via e-mail, fax or snail mail through Aug. 31.

Interested in getting involved?  Want to participate in the advocacy process of building and supporting our recreational fishery – and at the same time working more closely with government agencies? Get involved - get nominated.

Positions and present office holders are:

Officers

President – Dan Thomas

Vice president – Bob Mitchell

Secretary – Mike Sanger

Treasurer – Tom Couston

 

Lake Erie Fishery Review - continued

 

Catch Limits Set

continued from page1

growth will be sustained and contribute to a more robust, stable walleye fishery, starting in 2005.

                "The Lake Erie Committee has had a challenging year managing the walleye fishery,” said committee chair Rick Hoopes, PFBC fish chief. “While we are very optimistic because of the strong spawning in 2003, we all agree that we must take steps this year to protect the future of the fishery. We are very pleased with the cooperation among the jurisdictions on the lake and with the dialogue that has taken place between the management agencies and the affected stakeholders.”

                        Continued on page 21

Directors

Illinois – Robert Gaik

Indiana – Mike Shoonveld 

Michigan – Ron Dubsky

Minn. – Dave Koneczny

New York – Jay Levy

Ohio – Tom Mayher

Ontario – Darryl Choronzey

Penn.  – Ed Kissell

Wisconsin – Louie Kowieski

Voting will again be conducted by First Class mail only. Ballots will be mailed in September, votes counted and results announced in late October.

Send nominations to: Nominating Committee, 630-941-1196-Fax, P.O. Box 297, Elmhurst, IL 60126 - Snail mail, staff@great-lakes.org. ²
 

 

? Established 1972 ?

 

President

Daniel N. Thomas, Illinois

Vice President

Robert Mitchell, Michigan

Secretary

Michael D. Sanger, Wisconsin

Treasurer

Thomas G. Couston, Illinois

 

DIRECTORS

Illinois – Robert Gaik

Indiana – Mike Schoonveld

Michigan - Ronald Dubsky

 Minnesota - Dave Koneczny

New York – Jay Levy

Ohio - Thomas Mayher

Ontario – Darryl Choronzey

Pennsylvania - Ed Kissell

Wisconsin – Louis Kowieski

 

 

Position Statement

Representing a major interest in the aquatic resources of the Great Lakes states and the province of Ontario, the Great Lakes Sport Fishing Council is a confederation of organizations and individuals with a concern for the present and future of sport fishing, our natural resources and the ecosystem in which we live. We encourage the wise use of our resources and a search for the truth about the issues confronting us.

 

Inland Seas Angler

Great Lakes Basin Report

Publisher

Dan Thomas, 630/941-1351

Editor

Jeanette Thomas

Editorial Adviser

Bob Schmidt, 773/283-7871

Webmaster

Robert James, 630/530-7760

 

Ó Copyright 2002 by Great Lakes Basin Publications, the Inland Seas Anglers-Great Lakes Basin Report is the newsletter of the Great Lakes Sport Fishing Council, a federally recognized not-for-profit 501(c)(3) organization, and recognized for tax-deductible giving by the federal government.

Opinions expressed are those of the authors and not necessarily those of GLSFC, its officers or staff.  Reproduction of any material by paid-up members is encouraged, but appropriate credit must be given. Reproduction by others without written permission is prohibited.

Address Change: Please send six weeks in advance with old mailing label to Great Lakes Basin Report, P.O. Box 297, Elmhurst, IL 60126, (630) 941-1351; Fax (630) 941-1196; staff@great-lakes.org.

 

 

Lake Erie Fishery Review for 2003 - continued

Yellow Perch Projection

continued from page2

and 33% less than 2003 in management units 1 to 4 respectively. Estimates of abundance for age-3 and older yellow perch in 2004, however, remained among the highest in the time series in Units 1, 2 and 4, but to a lesser extent in Unit 3.

                In recent years, Lake Erie yellow perch populations have been composed of older fish in contrast to the 1970s. Strong year classes were produced during earlier periods of high nutrient enrichment and high adult mortality in Lake Erie. If catch-age model assumptions are representative, results imply that conditions were more favorable for reproductive success during the 1970s. While yellow perch populations prospered in Lake Erie’s past eutrophic state, they continued to thrive following reduced phosphorus loading and colonization of exotics such as Dreissena, Bythotrephes, white perch and round gobies.

                As there was no consensus on a single harvest strategy at this time, the Yellow Perch Task Group did not recommend an allowable harvest. ²

 

Yellow Perch Task Group Report for 2003

The lakewide total allowable catch (TAC) in 2003 was 9.906 million lbs. This allocation represented a 6% increase from a TAC of 9.333 million

lbs. in 2002. For yellow perch assessment and allocation, Lake Erie is partitioned into four Management Units (Units, or MUs). The 2003 allocation by management unit was 2.6, 4.2, 2.9 and 0.206 million lbs. for Units 1 to 4, respectively.

                The lakewide harvest of yellow perch in 2003 was 9.359 million lbs., (Table 1) the highest observed since 1990 (9.629 million lbs.). The 2003 harvest was only slightly (1.4%) above 2002. Harvest by management unit was 2.7, 4.2, 2.3 and 0.141 million pounds for Units 1 to 4, respectively. The 2003 harvest was within the lakewide total allowable catch.

                Lakewide, yield increased slightly in 2003 for OH (1.5%), ONT (2.3%), and PA (16%), but decreased for MI (42%), and New York (39%).

                Gill net effort was down in MU 1 (22%) and MU 2 (3.7%), but up 39.2% in MU 3 and 56.4% in MU 4 compared to 2002. Gill net effort remained generally low in 2003 compared to the 1990s and earlier decades.

                In 2003, sport harvest increased in MU 1 (10%) and MU 3 (40%) but decreased by 3% and 23% in Units 3 and 4 respectively. Angling effort increased only in MU 1 (31.4%) while decreases occurred in MU 2 (3.9%), MU 3 (26.7%) and MU 4 (38%).

                The yellow perch harvest in 2003 consisted mostly of the 1999 (age-4),

1998 (age-5) and 2001 (age-2) year classes. Recruitment of age-2 yellow perch was very strong to the sport fisheries.

                The estimates of age-2 recruitment for 2004 (the 2002 year class) were weak in all management units. Indications from juvenile trawl surveys, however, suggest the 2003 year class is strong throughout Lake Erie. The 2003 year class should have a positive effect on fisheries beginning in 2005 and more so in 2006, contingent on survival of juveniles.

 

Review of Walleye Fishery in 2003

The 2003 total estimated lakewide harvest of walleye was 2.7 million fish, which was a 12% increase from the 2.4 million fish caught in 2002 (Table 2). This harvest represented about 80% of the 2003 total allowable catch (TAC) of 3.4 million walleye and included walleye harvested in commercial and sport fisheries. The sport harvest of 1.3 million fish was the 2nd lowest since 1976 but represented an increase of 28% from 2002, which was the lowest in this period. The Ontario commercial harvest of 1.4 million fish was 1% higher than the 2002 harvest. The commercial harvests in 2002 and 2003 were the lowest since 1983 and only 66% of the 1975-2003 average. These harvests were low due to the reduced TAC during 2001-2003.
                Sport effort increased from 2002 up to a total of 3.3 million angler hours. This level of sport effort remains generally consistent with a declining trend that began in 1988. Sport effort declined by 4% in Management Unit 3, and increased slightly in Units 1 and 4 (2% and 22% respectively). The increase in effort in Management Unit 1 was due to increased effort in Ohio. Conversely, effort in Michigan declined in Unit 1 by 46%. Also observed, was an increase in sport effort of 52% in Unit 2 (Ohio).Lakewide commercial gill net effort decreased 8% to 12,512 kilometers of net and was the lowest total effort since 1981.

                Sport catch-per-unit-effort (CUE) increased in all areas of the lake. The lakewide average sport catch rate of 0.37 fish per rod hour was 14% below the 1975-2003 aver-age. However, it was a 16% increase over the 2002 value. In Management Units 2 and 4 catch rates were above the long-term mean, whereas in Units 1 and 3, sport catch rates were below the 1975-2003 mean. This marks the third consecutive year of increasing catch rates for the commercial fishery, and represents a reversal of the trend of declining CUEs observed since the mid 1980s. The increase in 2003 represents a 114% increase over the
 year 2000 catch rate of 53.2 walleye/kilometer of netting.

                A substantial portion of walleye harvested in both the sport (40.0%) and commercial (35.5%) fisheries were age-4 walleye (the 1999 year class). Age 2 walleye (the 2001 year-class) also contributed significantly in both fisheries, 26.4% (com-mercial) and 18.1% (sport).

                Across all management units, the mean age of walleye in the harvest ranged from 4.6 to 8.5 years old in the sport fishery and from 3.7 to 6.6 in the commercial fishery, with a mean of 4.5 years old for all walleye in the combined fisheries. The mean age of fish in both the sport and commercial fisheries increased from 2002 values. The mean age increased from 4.2 to 5.0 years (19%) in the sport fishery, and 3.5 to 4.1 years (17%) in the commercial fishery in 2003. The mean ages for both fisheries were above the long-term means of 3.9 (sport) and 3.5 (commercial) from 1975 to 2003.

                The 2003 population estimate was 29 million age-2+ walleye with approximately 9 million age-4+ walleye. The increase in the walleye population, from 2002 levels, was


 

 by the recruitment of a strong 2001 year class, contributing almost 19 million age-2 fish to the population.

                The 2002 year class is expected to be the lowest on record and is projected to add only 0.58 million age-2 fish to the 2004 popu-lation. The 2003 year class is the largest observed over the 1987-2003 series and may be comparable to the historically strong year classes of the 1980s. It is estimated that age-2 recruitment in 2005 will be approximately 30 million walleye.

                The '04 estimated abundance of age-2+ walleye is approximately 19 million, a 34% decline from '03. The abundance of age-4+ walleye (spawners) in 2004 was about 6 million walleye. However, due to the maturing 2001 year class, the abundance of age-4+ walleye in 2005 in projected to increase.

                The projected walleye abundance in 2004 (19 million fish) represents a decrease of 34% from the 2003 estimated abundance of 29 million walleye. An increase in walleye abundance is forecasted for 2005 (relative to 2004) as the exceptionally

 

 

 

Table 2. Lake Erie total walleye harvest in numbers of fish, from 1990 to 2003.

 

 

TAC Area (MU-1, MU-2, MU-3)

 

Non TAC Area (MU-4)

 

All Areas

Total

Year

Michigan

Ohio

Ontario

Total

NY

Penn.

Ontario

Total

1990

747,128

2,282,520

2,517,922

5,547,570

47,443

 

 

47,443

5,595,013

1991

132,118

1,577,813

2,266,380

3,976,311

34,137

 

 

34,137

4,010,448

1992

249,518

2,081,919

2,497,705

4,829,142

14,384

 

 

14,384

4,843,526

1993

270,376

2,668,684

3,821,386

6,760,446

40,032

 

 

40,032

6,800,478

1994

216,038

1,468,739

3,431,119

5,115,896

59,345

 

 

59,345

5,175,241

1995

107,909

1,435,188

3,813,527

5,356,624

26,964

 

 

26,964

5,383,588

1996

174,607

2,316,425

4,524,639

7,015,671

38,728

89,087

 

127,815

7,143,486

1997

122,400

1,248,846

4,072,779

5,444,025

29,395

88,682

 

118,077

5,562,102

1998

114,606

2,303,911

4,173,042

6,591,559

34,090

124,814

47,000

205,904

6,797,463

1999

140,269

1,033,733

3,454,250

4,628,252

23,133

89,038

87,000

199,171

4,827,423

2000

252,280

932,297

2,287,533

3,472,110

28,599

77,512

67,000

173,111

3,645,221

2001

159,186

1,157,914

1,498,816

2,815,916

14,669

52,796

39,498

106,963

2,922,879

2002

193,515

703,000

1,436,000

2,332,515

18,377

22,000

36,000

76,377

2,408,892

2003

128,852

1,014,688

1,457,014

2,600,554

27,480

43,581

32,692

103,753

2,704,307

strong 2003 cohort recruits to the population as 2-year-olds. ²

 

Lake Erie Forage Task Group

Eastern Basin

Rainbow smelt are the principal forage fish species in the offshore waters of eastern Lake Erie. Yearling-and-older (YAO) smelt (predominately age-1) have demonstrated a conspicuous alternate year cycle of increased abundance. An increase in YAO smelt abundance was expected in 2003, and indeed was the observed outcome among all of the agency trawl surveys.

                Young-of-the-year (YOY) smelt have remained the most abundant forage fish component. YOY smelt abundance increased basin-wide in 2003. Densities of age-0 smelt were approximately 4 to 12 times higher in Long Point Bay region than in the southern regions of the basin surveyed by NYS DEC and PFBC. According to OMNR trawl assessment the 2003 year class of rainbow smelt was the strongest observed over the 20-year history of the survey. Mean length of age-0 smelt increased and mean length of yearling smelt decreased in 2003.

                Several other species contributed to the size and diversity of the forage fish community of eastern Lake Erie in 2003. Most notable of these were emerald shiner, trout-perch, round goby, white perch and gizzard shad. Emerald shiners, predominately YOY, made significant contributions to the East Basin forage base during 2003.

                Round gobies emerged as a new species among the eastern basin forage fish community during the late 90s. Gobies continued to increase in density at a rapid rate and by 2001 became the most or second most numerically abundant species caught in trawl gear across areas surveyed in eastern Lake Erie.

Central Basin

In the central basin, overall forage abundance increased threefold from 2002, due to the largest YOY cohort since 1996. In both Ohio and Pennsylvania, smelt, shiners, yellow perch and white perch increased dramatically from 2002. Gizzard shad and trout-perch abundance also increased, but only in the eastern area for trout-perch and western area for the gizzard shad. In Pennsylvania, YOY round goby abundance decreased from 2002 and has decreased for the last two years. In Ohio, round goby abundance has remained stable since 2001.

                The only trends in YOY growth in the central basin were in rainbow smelt, walleye and yellow perch. Smelt have increased in size over the last two years and are slightly above the long-term average. Walleye and yellow perch have decreased in size over the last two and three years respectively. Both species are similar in size to the 1996 and 1997 cohorts.

                Adult walleye diets in the fall were dominated by shiner (62%), gizzard shad (22%) and smelt (13%) which is similar to the predominant prey species found in the trawl surveys. Round goby continue to be significant diet items in smallmouth bass (63%), yellow perch (49%) and white perch (13%).

Western Basin

Percid recruitment was the strongest since the survey began in 1987. Emerald and spottail shiner CPUE also increased. Clupeid CPUE decreased sharply. No YOY smallmouth bass were collected from Ohio waters in August or October 2003.

                Round goby CPUE decreased in 2003. These trends suggest the population may be stabilizing.

                Age-0 yellow perch size was the highest observed since 1998, exceeding the long-term average. Age-0 walleye size was the lowest observed since 1997, likely due to the high abundance of the 2003 year-class. Age-1 yellow perch were the largest since 1972 while age-2 were slightly larger than the previous year-class and similar to the long-term mean. However, age-2 walleye mean length and weight were slightly lower than those observed in 2002.

                Walleye diets continued to be dominated by clupeids in the western basin (94% by volume), with minor contributions from shiners and smelt.

 

Ohio’s Lake Erie Fisheries 2003

Walleye –The 2003 charter boat fishery harvest of 0.28 million fish was a 47% increase from 2002. Targeted walleye effort increased 9% compared to 2002. The targeted harvest rate increased 28% to 0.60 fish per angler hour, and was higher than the ten-year mean of 0.56. Boat limit trips ranged from 12% in District 3 to 34% in District 1 (Table 8). The majority of the walleye sport harvest was from the 1999 (40%) and 2001 (19%) year classes. Age-5 and older walleye constituted 36% of the lakewide catch. Walleye mean size increased across Districts 1 to 3 and averaged 502 mm (18") and 1,239 g (2.8 lbs.).

 

Yellow Perch – Private boat anglers harvested 6.7 million yellow perch and expended 2.0 million targeted angler hours during 2003. Harvest and targeted effort were the highest since the mid '80s. Harvest rate increased to 3.3 fish per angler hour. Private boat limit trips ranged from 17% in District 2 to 26% in Districts 1 and 3.

                The charter boat harvest and target angler hours increased 46% and 31%, respectively, from 2002. Harvest and targeted effort was the highest since the late 1980s. Harvest rates increased 17% from 3.8 fish per angler hour in 2002 to 4.5 fisher per angler hour in 2003. Percent of limit trips by charter anglers remained high at 42%.

 

Smallmouth Bass – The private boat effort of over 345,000 angler hours was an 11% increase from 2002. The harvest of 44,665 was a 42% increase from 2002 and the highest since 1999. As in previous years, the release rate (0.49 fish per angler hour) was considerably higher than the targeted harvest rate (0.07 fish per angler hour). The charter boat fishery showed a decrease in harvest (-41%) and targeted effort (-57%), with an increase in targeted harvest rate (39%) compared to 2002. The 1998 (32%) and 1999 (27%) year classes combined constituted 59% of the smallmouth bass harvest in Ohio’s waters. Smallmouth bass mean size averaged 422 mm (16.5") and 1,256 g (2.8 lbs.) lakewide.

 

Steelhead Trout – The combined private and charter boat harvest of 21,571 for 2003 was a 48% decrease compared to 2002. Steelhead trout are harvested primarily from the central basin, with 33% of the catch from District 2 and 66% from District 3. Anglers spent 15,555 combined (private and charters) targeted hours fishing for steelhead trout in 2003. The harvest rate was 0.20 fish per angler hour for the private boat fishery and 0.44 fish per angler hour for the charter boat fishery. During 2000, an additional category was added to the target species list (walleye/steelhead) in order to measure the number of angler trips targeting both walleye and steelhead. Total walleye/steelhead target angler hours for both fisheries decreased 80% from 51,474 angler hours in 2002 to 10,445 angler hours in 2003. The targeted harvest rate for the combination trips was 0.24 fish per angler hour for the private boat fishery and 0.35 fish per angler hour for the charter boat fishery. Lakewide, steelhead trout averaged 570 mm (22.5") and 2,424 g (6.5 lbs)

 

Steelhead Trout Program

The Division of Wildlife stocked 544,280 age-1 steelhead trout into selected Lake Erie tributaries in 2003. The Division of Wildlife completed its second annual stocking into the Vermilion River in spring 2003. Annual stockings of age-1 Little Manistee River strain steelhead trout were completed during the last week of April and first week of May, 2003, in the Chagrin (95,925), Grand (116,151), Rocky (106,736), and Vermilion (117,444) rivers, and Conneaut Creek (108,024). These steelhead averaged 130 mm (5.1 inches) in length at time of stocking. An additional 75,000 yearling steelhead were in Conneaut Creek by the Pennsylvania Fish and Boat Commission. This cooperative stocking program for Conneaut Creek is expected to continue. Target stocking numbers for Ohio Division of Wildlife steelhead will remain at Vermilion River, 55,000; Rocky, Chagrin and Grand rivers, 90,000 each; and Conneaut Creek, 75000. Extra fish stocked in 2003 were due to an accounting error in procuring fingerlings from Michigan. The Division of Wildlife continues to implement improvements to the Castalia State Fish Hatchery to meet annual target program demands for 400,000 yearling steelhead trout averaging 150-225 mm (6-9"). ²

 

2003 Sea Lamprey Management

Estimated spawning-phase abundance during 2003 was 4,150, which represents an increase over the 2002 estimate of 1,485, but remains well below the average calculated over the period from 1996-2001.

 

Tributary Information

·         Lake Erie has 842 (525 Canada, 317 United States) tributaries.

·         21 (11 Canada, 10 US) tributaries have historical records of production of sea lamprey larvae.

·         8 (3 Canada, 5 US) tributaries have been treated with lampricide at least once during 1994-2003.

·         Of these, 5 (2 Canada, 3 US) tributaries are treated on a regular cycle.

 

Lampricide Control

Lampricide treatments were completed on 3 Lake Erie tributaries (1 Canada, 2 U.S.) scheduled for treatment.

 

Assessment

·         Assessments of larval populations were conducted in 13 tributaries (2 Canada, 11 U.S.).

·         Populations of larvae were estimated in 3 tributaries (0 Canada, 3 U.S.)

·         Sea lamprey larvae were detected in Delaware Creek for the first time since lampricide treatment in 1986. A quantitative assessment is planned during 2004.

·         Surveys indicate that the Young’s Creek barrier has successfully blocked sea lamprey spawning migrations since the 2001 treatment. Limited larval production continues downstream of the barrier.

·         475 sea lampreys were trapped in 4 tributaries during 2003.  ²

 

Pennsylvania Lake Erie Fishery

Status and Trends 2003

Commercial Fishery Summary

Recommended allowable commercial quotas have not been attained in recent years; only one license is actively fishing commercial trap nets. Annual exploitation of yellow perch, walleye and whitefish has been minimal and remained so in 2003.

Yellow Perch – Landings of yellow perch rebounded in 2003 from declines of the last couple of years, due primarily to the increase in the perch population. The commercial TAC for 2004 is 36,000 pounds, slightly higher than 2003. The trap net fishery is expected to land only about 12% of this allotment in 2004, about 2% or less of the fishable perch population in Lake Erie waters of Pennsylvania.

Walleye – As in the past three years, the commercial landings of walleye are small and trap net exploitation is considered virtually immeasurable. Landings in 2004 are not expected to increase substantially since directed or target effort will not increase.

Lake Whitefish – Few whitefish were reported in commercial landings in 2003. Declining abundance and distribution restrictions to deep waters in summer months made whitefish generally unavailable to the shallow water trap net fishery.

Fish Stock Status and Trends

Yellow Perch – In Pennsylvania waters, the perch stock age-2 and older in 2003 represents its zenith measured over the last two decades. The persistence of strong year classes the 1994, 1996, 1998, and 1999 contributing to the fisheries are responsible for the elevation of perch population levels. Furthermore, in 2003, a large 2001 cohort recruited to the maturing stock and a very large perch year class was produced in 2003. Continued high survival is expected to allow a large carryover in the next two years, further enhancing the size of the stock.

Walleye – The Pennsylvania walleye population is generally recognized as a composite of locally spawned fish and immigrants from both the eastern and western basin origins. Tag return data confirms that much of the larger, older female walleye taken by the sport fishery are post spawn migrants from western Lake Erie.

Lake Whitefish – Strong whitefish year classes have not been produced in eastern Lake Erie waters since the 1990s. However, the 2003 whitefish cohort appears to be the largest hatched since 1989.

Forage Fish Populations – Smelt have reached a low level of abundance in Pennsylvania’s eastern basin waters. Following precipitous declines in year class production, annual young-of-the-year smelt numbers appear to be holding at diminutive levels. Few smelt older than age-1 were represented in assessment catch surveys. The 2003 smelt year class has been the most “sizable” cohort produced since 1994 (save the 1996) and some improvement in survival to age groups 1++ was also noted.

                The most frequently caught species were yellow perch (60%), walleye (14%), steelhead (8%), sheepshead (4%), black bass (4%) and white perch (2%). The most frequently harvested species were yellow perch (73%), walleye (19%) and steelhead (5%).

 

Walleye

Walleye Angler Effort: For the second consecutive year, walleye failed to attract the majority of the open lake boat angling effort.  Anglers directed an estimated 159,039 hours of effort fishing for walleye, a 22% increase from 2002, and a 44% decrease over the average of the last eight years.

Walleye Catch and Harvest: Walleye anglers caught an estimated 52,289 walleye and harvested 43,581 walleye, a 126% increase in catch and a 97% increase in harvest from 2002 catch and harvests. Although the catch and harvest had doubled from 2002, the 2003 walleye catch and harvests were still about 40% below the average of the last eight years.

                In 2003, 68% of all walleye anglers caught a walleye and landed a fish about every 3.5 hours. The 2003 catch rate of 0.28 walleye per hour doubled from 2002 and was above the long-term average of 0.25 walleye/angler hour. Typical of all years, walleye fishing was better in central basin waters.

Length and Age of Harvested Walleye: Anglers creeled walleye ranging in size from 13 to 30", with an average length of over 23". Approximately 3% of the harvest was under the 15” minimum size limit.

Smallmouth Bass

In 2003, anglers spent an estimated 49,417 hours fishing for smallmouth bass in open lake waters of Lake Erie. This was the first increase in bass angler effort since 1998.  Effort increased 52% from 2002, but was still 44% below the average of the last eight years.  Catch estimates increased 27% when compared with the 2002 angling season, but declined 35% from the eight-year average. Catch and release fishing continues to dominate the fishery as 97% of the bass that were caught were released. Total estimated catch was 79,000 bass, with an estimated harvest of 2,763 bass.

                Nearly every angler (95%) targeting smallmouth was successful in catching a bass and landed a bass every 35 minutes (1.69 bass/angler hour).  Smallmouth bass catch rate by boat anglers also increased in 2003, although not as dramatically and remained below the 17-year average.

 

Yellow Perch

Anglers directed an estimated 187,770 hours at yellow perch in 2003. For the second consecutive year, perch surpassed walleye in directed angler effort. Anglers caught an estimated 478,681 perch and harvested 414,050 perch. This represented a slight decrease (4%) in catch and an incremental increase (0.5%) in harvest from 2002 estimates. Relative to the average over the last eight years, catch has increased 140% and harvest increased 156%.

 

Steelhead Trout

Stocking: The PFBC stocked 718,000 steelhead, 70,000 coho salmon and 22,000 brown trout in 2003. The number of anadromous salmonids (primarily coho and steelhead) stocked by the PFBC has averaged about 1.3 million yearlings since 1995. A total stocking of 810,000 trout and salmon in 2003 represents a 39% decrease from the 1987-2003 average of 1.3 million yearlings. The combined efforts of the PFBC and Cooperative Hatchery Units resulted in 867,000 steelhead smolt stockings in 2003. Decreased emphasis on coho salmon stocking has been the primary reason for declines in stocking rate. 2003 was the final year that the PFBC stocked coho salmon.

                Anticipated steelhead stocking in 2004 by the PFBC is about 1,045,000 yearling steelhead, slightly above target stocking levels.  Cooperative hatchery additions should supplement agency stocking for a total of about 1,200,000 yearling steelhead in 2004.

Steelhead Fishery: Over 90% of the total steelhead fishing effort, catch and harvest take place in the tributaries.

Steelhead Angler Effort: About 84% of the steelhead fishing trips were by tributary shore anglers, and 16% were by boat anglers. Results estimated the open lake steelhead effort by boat anglers at 15,535 hours. This was a decrease of 48% from estimates generated in 2002 and a 56% decrease over the eight-year average of 35,000 hours.   Most of the steelhead catch occurred in Elk Creek, Crooked Creek, Trout Run, Walnut Creek, and Sevenmile Creek.

Steelhead Angler Success and Catch Rate: Survey results showed that open lake boat anglers targeting steelhead were successful on half of their trips and harvested a steelhead about every 7.7 hours.

                Much better steelhead fishing exists in the tributaries. The catch rate in the tributaries is about four times higher than the boat catch rate. The catch rate by tributary anglers of 0.96 steelhead per line hour represents the third highest catch rate in the time series from 1987-2003.

²

 

Ontario Waters of Lake Erie in 2003

Commercial Fishery

In 2003, total commercial landing from the Ontario waters of Lake Erie was 21.7 million lbs, a decrease of 3.5 million lbs (14%) from 2002. The value of the total commercial landings in 2003 was $25.4 million, a decrease of $4.9 million (16%) from 2002.

Rainbow Smelt – The total landings of rainbow smelt decreased slightly by 1% to 7.4 million lbs in 2003. OE-4 had 45% of total smelt landings, OE-2 and OE-3 each had 22% and OE-5 10%. In OE-4 age-2 smelt dominated the harvest throughout the year contributing 65% of the harvest in winter to 39% in the fall. Ages 1 to 3 comprised over 90% of the harvest by season except in the fall in OE-4 when YOY contributed 24% and ages 1 to 3 contributed 72%.

                The commercial fishery harvested 46% of the quota allocated for 2003. Harvest levels have declined gradually from a high of 37.4 million lbs in 1982. The landed value of rainbow smelt was $1.6 million.

Yellow Perch – Yellow perch landings increased 2% to 5.06 million lbs in 2003. Ages 4 and 5 dominated (73%) spring and summer catches in OE-1.

                The commercial fishery harvested 100% of allocated 2003 quota in OE-1 and OE-2 and 94% in OE-3 to OE-5. The landed value of yellow perch decreased significantly by $3.5 million (24%) to $10.9 million in 2003. The decrease was a result of a reduction of price per pound from $3 in 2002 to $2.23 in 2003.

Walleye – The total landings of walleye in 2003 were the same as in 2002, 3.9 million lbs. The entire 2003 quota was harvested.

                The landed value of walleye increased 1% from last year to $8.8 million.

Lake Whitefish – The total landing of lake whitefish decreased 0.5 million lbs (43%) to 0.6 million lbs in 2003. Lake whitefish total harvest was primarily caught in OE-1 (61%) and OE-2 (30%). A broad range of ages (age-4 to 10+) comprised spring harvest of lake whitefish in OE-1 to OE-3. Fall harvest in OE-1 was comprised primarily of age-6 (29%) and older aged fish.

                The commercial fishery harvested 34% of the quota allocated for 2003. The landed value of lake whitefish decreased $0.5 million (42%) to $0.7 million in 2003.

 

Long Point Bay Creek Survey

The total estimated angling effort of 76,669 rod hours remained below the average for the time series (115,898 rod hours), and represents a 51% decrease from the 1998 peak of 155,486 rod hours. In 2003, effort targeted at smallmouth bass (68,687 rod hours) was higher than in 2002, as were estimates for catch and harvest. The catch-per-unit-effort (CPUE) for smallmouth bass in 2003 (0.530) was higher than the long-term average (0.488), but still well below the time series high of 0.715 observed in 1998.

                The 2003 estimated effort directed at largemouth bass (5,550 rod hours), while higher than in 2002, remains well below the long-term average.

                Estimated effort targeting yellow perch (15,893 rod hours) was similar to that of 2002 but below the long-term mean (12,018) and 45% less than a 15-year high of 28,795 which occurred in 2001. Average catch rate for yellow perch anglers (0.567) had increased slightly from that of 2002 (0.462) however these two years represent the lowest CPUEs in the time series and are less than one third of the long-term average.

 

Trends in Abundance and Bio-mass of Yellow Perch 1986-2003

Yellow perch were abundant in Long Point Bay during the late 80s. Population size decreased during the early 90s and remained at low levels until 2000, when two-year-old perch from the strong ’98 year class began recruitment into the population. The ’98 year class has remained the dominant cohort in index gill net catches since 2000; contributing 78, 85, 72, and 51% of the annual survey total perch catch (in number) from 2000 to 2003. The 2001 and 1999 year classes represented 22% and 18% of yellow perch caught, respectively.

 

Salmonid Stocking Summary

In 2003, a total of 52,672 yearling trout were stocked into the Ontario waters of Lake Erie.  The MNR Normandale Fish Culture Station (NFCS) stocked 11,672 yearling rainbow trout at two locations in Big Creek. A left pectoral clip was applied to all fish.

                The NFCS also transferred 65,000 rainbow trout fingerlings and 100,000 brown trout eggs to the Lake Erie Salmon and Trout Club in Port Stanley in fall 2002. These were raised in the club’s hatchery facility in Port Stanley and were stocked in 2003 as follows:

(a)     27,000 yearling rainbow trout and 7,000 brown trout into Mill Creek (a tributary of Kettle Creek) in May 2003; and

(b)     10,000 yearling rainbow trout into Erieau Harbour in September 2003.

²

New York Summary

NY Waters of Lake Erie for 2003

Botulism: During 2003 type-E botulism-related mortalities continued along New York’s portion of Lake Erie, although as a much smaller incidence than observed from 2000-2002. A minor fish kill affecting smallmouth bass and freshwater drum was observed during late August, and laboratory tests confirmed the presence of the botulinum toxin.

 

Yellow Perch: An autumn trawl survey recorded the highest abundance of young-of-year (YOY) yellow perch ever measured in this 12-year program, exceeding the previous highest measure by nearly 5-fold. YOY walleye and lake whitefish were also commonly encountered in samples for the first time in the history of this trawling program.

 

Warm Water Fishery: Our walleye-yearling index ranked the 2002 year class as weak relative to this 23-year time series. Overall smallmouth bass catch rates remained slightly above the long-term average with age-4 fish making the largest contribution. Sub-adult smallmouth bass recruitment measures indicate that both the 2000 and 2001 year classes are below average abundance. Adult yellow perch catch rates remained high in 2003, but dropped below the recent peak observed in 2002.

                An annual inter-agency walleye tagging study has now extended 14 years. The 2003 results continue to portray New York’s walleye spawning stocks as experiencing high survival and low annual exploitation rates.

 

Coldwater Fishery: Total gill net effort of 60 lifts collected 550 lake trout, the most ever sampled in this survey, with 17 year classes represented between age-2 and 19. Young lake trout ages 2-5 represented the majority (83%) of the catch, but age-10 and older fish, which were absent in the 2002 survey, were also well represented. Overall abundance of both lake trout and burbot were the highest in the time series. Round gobies became a prominent diet item for lake trout, occurring in over 15% of the stomach samples, and were the most abundant diet item in burbot (61%) stomachs.

 

Sea Lamprey: Observed sea lamprey wounding rates on adult lake trout increased substantially to 10.4 wounds per 100 fish. The majority of the wounds occurred on lake trout over 25" with fish over 29" being the preferred host.

 

Stocking: A total of 456,670 salmonines were stocked into the New York waters of Lake Erie in 2003. Steelhead continued to be the most numerous species stocked (251,250) followed by lake trout (120,000). Cazenovia Creek, a tributary to the Buffalo River, was stocked with steelhead (9,930) for the first time with hopes of establishing another fishery closer to the city of Buffalo and its surrounding suburbs.

 

Recreational Harvest:  Open water anglers experienced the first decline in catch rates in the last 5 years, averaging 0.12 fish/hour, well below the average of 0.205 fish/hour. Tributary anglers, on the other hand, reported another excellent year, landing 1,179 trout and salmon. Cattaraugus Creek generated the most effort of the Lake Erie tributaries, accounting for 53% of the total trips, 61% of the effort, and 63% of the total catch. Overall tributary catch rates have stabilized over the past 5 years at around 0.50 fish/hour.

                A management plan for wild steelhead is currently being developed to guide sampling and provide objectives for the future.

 

Sport Fishery Assessment: The 2003 open lake sport fishing effort measured for the New York waters of Lake Erie was estimated as 352,128 angler-hours, ranking it as the second lowest annual total of the 16-year survey. Peak fishing activity occurred during July and Dunkirk Harbor was the most frequently used access site in 2003. Walleye anglers comprised the largest fraction of the overall angling effort, followed by bass anglers.

                Total estimated walleye harvest was 27,478 fish, ranking 2003 as the 11th largest walleye harvest in the 16-year survey. Smallmouth bass remained the most frequently caught species (118,974 fish) by boat anglers, but the estimated smallmouth bass harvest of 8,640 fish ranked as the lowest measured for the entire time series. The 2003 yellow perch harvest of 24,590 fish declined from a recent peak observed in 2002, but remained well above an extended period of poor fishing through the 1990s. Lake trout emerged as the most caught salmonid species in 2003.

 

Forage Fish Assessment: An annual forage fish bottom trawling survey found high densities and increasing species diversity in the New York waters of Lake Erie. YOY smelt and round goby ranked first and second, respectively, among the most commonly encountered forage fishes. Emerald shiners also continued as a recent annual contributor to the forage biomass in 2003. A historically predictable alternating year class cycle of yearling smelt abundance dampened in recent years with yearling-and-older (YAO) smelt in 2003 only making a modest contribution to this trawl sample.

                Rainbow smelt remain the principal forage fish species found in an annual summertime diet study of angler caught walleye.

 

Walleye Spawning Stream Rehabilitation: In 2003 springtime electrofishing surveys on Cattaraugus Creek continued to document high densities of spawning-phase walleye. Stocking contributed at least a fraction of the spawning-phase walleye now sampled in Cattaraugus Creek.

 

Warm water Gill Net Assessment for 2003

Nearly every gill net sample obtained from inshore areas less than the 50 ft. contour had at least detectable, or sometimes massive amounts, of algae coating the monofilament gill net webbing. Fouling by algae undoubtedly made these nets more conspicuous to fish and very likely dampened catchability in 2003.

 

Walleye: The overall abundance index for walleye in 2003 remained below the long-term average abundance since 1981. The age composition of this walleye sample was composed primarily of the age-2 and age-5 cohorts representing the 2001 and 1998 year classes respectively. Also, the once dominant 1984 year class of walleye still remains detectable at age-19 in the 2003 samples. This gill net assessment has had a juvenile walleye emphasis since its inception, with age-1 and age-2 walleyes comprising a large fraction of the total walleye sample each year. Yearling walleye catch rates ranked the 2002 year class as weak relative to the entire time series.

 

Smallmouth: Smallmouth bass catch rates in 2003 remained slightly above the average value for this 23-year time series. Age-4 individuals made particularly large contributions to this 2003 sample, which included 16 age groups from age-0 to age-16. The long-term recruitment indices for juvenile, age-2 and age-3, smallmouth bass rank the 2000 year class as weak in the time series. Early indications from this same juvenile recruitment index also suggest the 2001 year class is not particularly abundant.

 

Yellow Perch: In the 50 to 100 ft. stratum, yellow perch continued to be represented at high levels of abundance first observed in 2000. Age-2 through age-5 yellow perch were all commonly encountered age groups in the 2003 collections and individuals greater than age-7 remained scarce. Only since 2000 have adult cohorts of yellow perch contributed measurably to this annual sample.

 

Walleye Tagging Study

During the 14 years New York has participated in this interagency tagging study, 16,679 walleye have been tagged in New York’s portion of Lake Erie. During April 2003, 630 walleye were collected in New York waters and affixed with jaw tags as a continuation of this effort to examine walleye distribution and exploitation rates. The two tagging sites sampled in 2003 were Van Buren Bay and Cattaraugus Creek. Walleye tagged for this study were collected by trap nets and boat shocker.

                Results: Since the inception of this tagging study, 1,431 tag recoveries originating from the New York tagging effort have been reported by anglers and the Ontario commercial fishery. Eighty-nine (89) of these recaptures occurred during 2003.

 

2003 Cold Water Fishery Assessment

A self-sustaining lake trout population continues to be the major thrust of New York’s Great Lakes coldwater fisheries management programs, in cooperation with the PFBC, USFWS, and the USGS at Sandusky, Ohio.

                New York’s 2003 annual lake trout assessment program consisted of: (1) standardized deepwater gill netting in August, and (2) monitoring sea lamprey wounding activity as it impacts lake trout.

                Gill net assessment sampled 550 individuals in 60 lifts, which was the most lake trout ever sampled during this survey. Seventeen age classes, from age-2 to 19, were represented in the sample of 491 known-aged fish. No age-1 fish were sampled for the first time in the last five years.

                The largest lake trout sampled measured 39" and weighed 28 lbs. One hundred and four mature females were sampled in 2003. These fish ranged from age-4 to 18 and generated a mean age of mature females of 6.2 years. It reflects the prevalence of the younger age-classes in the Lake Erie lake trout population at this time.

                Trends in relative abundance of lake trout caught show a large increase over last year. Returns of the 2002 stocking as age-1 and age-2 fish in our surveys indicate that this is the best survival of stocked lake trout experienced in Lake Erie since 1985.

                Rainbow smelt remained the main prey item in lake trout stomach samples, occurring in 76% of the lake trout stomachs, and round gobies comprising 16% of the lake trout diet in 2003 samples.

                The 2003 Lake Erie coldwater assessment survey was characterized by the highest catches of lake trout observed in the survey’s time series. The current lake trout population in Lake Erie is dominated by younger cohorts aged 2 through 5.

 

2003 Sea Lamprey Assessment

Observed fresh wounds on lake trout greater than 21" total length increased substantially in 2003 to 10.4 wounds per 100 fish. Similar to past years, almost all of the fresh wounds occurred on larger lake trout greater than 25" with the fish over 29" being the preferred host.  Similar to the past two years, the highest sea lamprey nest counts were found in the main branch of Clear Creek at 26.5 nests/mile. The North Branch of Clear Creek, a tributary to Clear Creek, had a similar nesting rate of 26.1 nests/mile. The largest increase in nests was found on Canadaway Creek, which saw an eleven-fold increase to 15.0 nests/mile.  In 2002, fresh lake trout wounds were at their lowest rate in the past 10 years.

 

2003 Salmon Stocking Summary

The 456,670 salmonines stocked into New York’s waters of Lake Erie in 2003 represents a 15% increase over the recommended 397,500 fish due to the availability of surplus fish within the state hatchery system. Overall, however, it ranks as the fourth lowest yearling stocking total of salmonines since 1982. Lake trout, brown trout, domestic rainbow, and steelhead were responsible for all of the salmonines stocked in 2003.

                The current lake trout goal of 120,000 yearlings stocked was met for the fifth straight year.

                This was the second year brown trout yearlings replaced domestic rainbow trout in Lake Erie with 43,420 yearlings stocked in Barcelona Harbor, Dunkirk Harbor, Cattaraugus Creek, and Point Breeze Marina. Domestic rainbows (2,500) were only stocked in Buffalo Harbor to provide a supplemental spring fishery around the fishing pier and boat docks. Steelhead were still the most numerous salmonid species stocked with 251,250 stocked in 9 tributaries and Dunkirk Harbor. Cazenovia Creek in Erie County was stocked for the first time in 2003 with 9,930 steelhead. These fish were shifted from Chautauqua Creek to Cazenovia Creek in hopes of establishing another fishery closer to Buffalo and the surrounding suburbs. Chautauqua Creek will still receive a healthy 40,000 yearlings annually.

 

Walleye Diet Study

Ongoing walleye diet investigations find smelt as the most abundant prey in adult walleye stomachs. However, the increasing presence of clupeids and other forage fish species beginning in 2001 may be a reflection of increased species diversity now observed in the forage fish community.

 

Forage Trawl Survey

In 2003 YOY smelt and round goby ranked first and second, respectively, in abundance of forage fishes. Round goby only recently emerged in the late 1990s as a new species and peaked in abundance during 2001 and 2003. Beginning in 2001 emerald shiners have also become a predictable annual contributor to the forage biomass.

                Although forage fish abundance remained high, yearling smelt continued to contribute only a small component in numbers and biomass to overall forage fish index obtained from bottom trawling.

 

Open Lake Sport Fishing Survey

Overall 2003 open water sport fishing effort was estimated as 352,128 angler-hours. Peak fishing activity occurred during July and the most frequently used site in 2003 was Dunkirk Harbor. The 2003 fishing effort estimate ranks as the second lowest annual total of the 16-year time series. The lowest total occurred in 2002. During the 2003 fishing season, walleye angling was the largest component of the boat fishery with 46 % of the overall angling effort. Bass angling ranked second with 32 % of the total. Among the remaining effort, anglers fishing for “anything” ranked 3rd with 10% of the overall effort, and targeted yellow perch effort accounted for 9% of the total in 2003. The remaining 3% was distributed almost equally among trout, northern pike and musky anglers returning to the Buffalo Small Boat Harbor.

                The total estimated daytime walleye harvest was 27,478 fish, ranking 2003 with the 11th largest walleye harvest in the 16-year survey. The 2003 walleye fishing effort total that accompanied this walleye harvest was the 2nd lowest observed in the 16-year time series.

                The 2003 walleye sport fishery was centered in offshore waters generally adjacent to Dunkirk, New York. The overall targeted walleye catch rate during the 2003 fishing season was 0.15 fish per hour, which was the modal value for the time series. This targeted walleye catch rate also increased for the second consecutive year. The average total length of harvested walleyes in 2003 was 24.0 inches and near the average (23.8 inches) for the entire time series.

                Smallmouth bass harvest was estimated as 8,640 fish, which ranks 2003 with the lowest bass harvest for the entire 16-year survey. Overall 2003 bass fishing effort has been similar each of the last 3 years and near the average for the time series. The 2003 smallmouth bass harvest also remained very small, relative to the bass catch by boat anglers. Smallmouth bass remained the most frequently caught species (118,974 fish) by boat anglers by a very wide margin. The largest component of the smallmouth bass catch and harvest was attributed to anglers encountered at Buffalo’s Small Boat Harbor. The 2003 overall catch rate by bass anglers was 1.06 bass per hour, and mean length of harvested smallmouth bass was 16.0" in 2003.

                The yellow perch harvest (24,590 fish) in 2003 declined from a recent peak the previous year, but remained the sixth highest harvest observed in the entire 16-year survey. The '03 harvest was centered in the vicinity of Cattaraugus Creek, NY. The 2003 overall catch rate was 0.90 perch per hour and remained similar to the highest values observed in the time series. The mean length was 10.9 " in 2003.

                A notable decline in boat fishing effort, first observed in 1999, has apparently continued through 2003. However, Lake Erie’s decline in fishing effort seems to remain consistent with broad trends observed in other waters and may be in response to factors independent of fishing quality.

 

Commercial Fishery Assessment

A small commercial fishery employing trap and hoop nets and targeting yellow perch has occurred since 1986 legislation prohibited the use of gill nets in the NY waters of Lake Erie. Two fishermen reported commercial fishing activity during 2003.

Commercial landings reported totaled 1,048 lbs. of yellow perch, 1,383 lbs. of burbot, 71 lbs. of rock bass, 21 lbs. of suckers, and 2 lbs. of catfish. The 2003 commercial yellow perch harvest declined by 46% from 2002, while trap netting effort was almost identical between 2002 and 2003, reported at 89 vs. 91 trap net lifts, respectively. Fishing activity was reported from May through September 2003.

²

Lake Michigan Fishery Review for 2003 - continued

Recreational Fishery Summary

continued from page 1

Chinook Salmon: Chinook salmon harvest rates were up markedly in the Northwest and Green Bay regions. Over 1.5 million Chinook salmon were harvested in the Northwest and Southwest regions, which were at or above levels observed in the mid 1980s. (Table 3)

 

Coho Salmon: Coho salmon harvest shows high annual variation but continues to come from southern Lake Michigan. Both harvest rates and numbers harvested in 2003 were down compared to 2002, but were well within the range of values reported over the last 15 years. (Table 3)

 

Rainbow Trout: The 2003 rainbow trout harvest from Wisconsin, Illinois, and Indiana statistical districts are the third lowest on record; only 63,000 steelhead were harvested compared to an average of 105,000 during the last ten years. Harvest rates were uniformly low across all statistical districts with a peak rate of <0.04 rainbow trout harvested per angler-hour in the Southeast region. (Table 3)

 

Yellow Perch: Harvest rates for yellow perch continued to decline in Green Bay where anglers averaged 0.5 perch per hour. Both harvest rates and angler effort for perch are at record lows for the Green Bay region. The Southeast and Southwest regions each harvested over 200,000 yellow perch in 2003 while less than 70,000 were harvested in Green Bay. (Table 3)²

 

Trout and Salmon Stocking, 1976-2003

Stocking information was provided by the DNRs of Illinois, Indiana, Michigan and Wisconsin, and from Federal Fish Hatcheries. Not all agencies have officially verified the stocking numbers.

 

Lakewide Trends: The number of trout and salmon stocked into Lake Michigan in 2003 totaled nearly 14.2 million fish, an increase from 2002 but still lower than the historical average of nearly 15 million. (Table 4)

 

Chinook Salmon: Nearly 4.7 million Chinook salmon were stocked, which is the highest stocking level since 1998 but still well below the numbers stocked between the 1980s to early 1990s. Michigan and Wisconsin increased Chinook salmon stocking by 20% and 12%, respectively, compared to 2002 while there were slight declines in Indiana and Illinois resulting in a combined reduction of 27,000 Chinooks. Annual stocking has ranged from 2.8 million Chinooks in 1977 to 6.4 million in 1995.

 

Coho Salmon: Over 3.1 million coho salmon were stocked which is above the historical average of 2.7 million and is the second highest total since 1989. All states except Illinois were above their historical average for coho salmon stockings; Illinois did not stock coho salmon in 2003.

 

Rainbow Trout/Steelhead: Rainbow trout stocking was close to the long-term average; nearly 2 million fish were stocked. High relative stocking rates for both Wisconsin and Indiana were evened out by the absence of stocking by Illinois in 2003, and a reduction of 210,000 fish from the long-term Michigan average.

 

Brown Trout: Over 1.6 million brown trout were stocked. This number is down slightly from last year due to an 11% reduction in brown trout stocking by Wisconsin. Wisconsin continues to stock the majority (65%) of brown trout.

 

Brook Trout: Brook trout stocking continues to decline in Lake Michigan. In 2003, brook trout stocking was at its lowest point since 1976. Only Wisconsin stocked brook trout; the 24,000 fish stocked is 10% of the historical lakewide stocking average.

 

Splake: In 2003 roughly 100,000 splake were stocked, similar to levels in recent years. Michigan (79%) and Wisconsin (21%) were the only states to stock splake.

 

Lake Trout: Over 2.6 million lake trout yearlings were stocked in 2003. This is below the long-term average of 2.8 million.

 

Marked Fish: Over 5 million trout and salmon, excluding lake trout, were stocked with designated fin clips in 2003.

 

Status of Chinook Salmon, 1985-2003

In 1999, Chinook stocking was reduced in hopes of minimizing risk to the fishery associated with instability in Chinook survival. Lakewide harvest levels were highest during 1985-1987 and declined dramatically during 1989-1995. Since 1996, Chinook harvest has been increasing with recent levels similar to those prior to the 1987-1988 decline. The harvest in 2002 was over 6.5 million lbs.

                Relative abundance catch-per-effort (CPE) from surveys indicated a rebuilding of the population in the 1990s. However, preliminary data suggest a decline in survey CPE in 2003.

 

Natural Reproduction

Approximately 20-30% of the Chinook in Lake Michigan are of natural origin. Natural production of smolts has been measured or estimated by various sources during 1985-2003. Production during the time period is approximately 2.2 million smolts lakewide, an amount equal to ½ of the current number of fish stocked.

                Chinook declined during the 1996-1998 period when alewife abundance was lower and winter temperatures were colder, and then increased again in 1999 in the presence of the strong 1998 year class of alewife and a milder winter. Since 2001, however, Chinook size-at-age have decreased.

 

Forage Abundance

Lakewide biomass of adult (age 1 and older) alewives in Lake Michigan during fall 2003 was estimated at 42.9 kt. The 1998 year-class constituted the bulk of this lakewide biomass. It appears that the 1998 year-class was an unusually large one, the extraordinarily warm water temperatures during the spring and summer of 1998 likely led to this large year-class being produced.

                Condition of alewives dropped by about 15% between the 1984-1994 and 1995-2001 time periods. This reduction in condition persisted in years 2002 and 2003 as well. The drop in condition was likely due to the decreased availability of Diporeia in the diet of alewives beginning in 1995. Preliminary data from determinations of caloric density in alewives has indicated that caloric density of Lake Michigan alewives declined by about 35%, between the 1984-1994 and 1995-2002 time periods.

                Because we have no reason to believe that any year-class produced after 1998 is nearly as strong as the 1998 year-class, we would expect another decline in adult alewife abundance between fall 2003 and fall 2004. Note that the average adult alewife biomass during 1982-2003 was 26.5 kt. Thus, the fall 2003 level of biomass was considerably higher than the average during the post-1982 period. Because we expect a substantial decline in adult alewife abundance during the 2004 growing season and because alewife caloric density decreased after 1995, we would expect a decline in Chinook salmon growth rate during 2004.

                Survey results suggest that Chinooks may have entered the winter of 2003-04 with very low energy reserves.

 

Summary

In the upcoming year, the Salmonid Working Group (SWG) will evaluate the success of the stocking reduction by summarizing data from Chinook salmon year classes stocked prior to 1999 (first year of reduction), and from 1999-2002.

                Ultimately, however, it is up to the Lake Michigan Committee (and the Great Lakes managers) to define a long-term strategy for manipulation of Chinook salmon populations. The Lake Michigan Fish Community Objectives state that we should suppress alewife populations for native fish rehabilitation, while at the same time minimizing the risk to the sport fishery associated with instability in Chinook survival. Defining the relative importance of these two potentially conflicting goals will help to further refine and focus Chinook salmon research and assessment efforts on Lake Michigan.

 

2003 Harvest of Fishes

The total biomass of all fish harvested during 2003 is estimated at 16.4 million lbs. The peak harvest for the survey period (1985) to present) was 56.6 million lbs. during 1985. Harvest averaged 41.4 million lbs. from 1985 through 1992, and 20.3 million lbs. from 1993 to the present, with a general downward trend. The '01 and '02 harvest estimates show a slight increase, primarily driven by salmonid sport harvest increases. The bulk of the reduction in harvest during the early 1990s is due to closure of the commercial yellow perch and alewife fisheries as well as reduction in Chinook sport harvest.

                Overall harvest levels since 1993 have been within sustainable harvest limits of 12.2 to 25.5 million lbs., as outlined in the Fish Community Objectives for Lake Michigan.

                The salmonine harvest of 9.5 million lbs. during 2003 was 2 million pounds less than the previous year but similar to the level in 2001. Salmonine forage appears to be plentiful, however, the harvest reduction is an area of concern.

                Chinook harvest during 2003 reached 7 million lbs., which is a slight reduction from 2002 levels. This level however, was still higher than the average for the period 1988 to 2001.

                Coho salmon harvest levels were estimated at 1 million lbs. and has decreased from the previous 4 years.

                Steelhead trout have continued to decrease since record levels in 1998 (1.3 million lbs.) and reached a level (710,000 lbs.) comparable to those prior to 1987.

                Lake trout harvest continues to decline. Harvest was the lowest during the 18-year period, at just over 600,000 lbs., which continues to be an area of concern for rehabilitation efforts. Only 6.6% of the salmonid harvest was made up of lake trout, possibly due in part to the continued availability of the other salmonid species.

                The brown trout fishery also reached an all time low for the 18-year period of 222,000 lbs. harvested. This species provides a supplementary nearshore fishery for many agencies.

                Walleye are continuing to gain interest with the nearshore fishery. Indiana has reported an increase in the winter nearshore walleye fishery. On a lakewide basis however, levels remain below the target of 200,000 to 400,000 pounds for the 18-year period, except for 1994 through 1996 and 2000.

                The estimated commercial harvest during 2003 reached a record low of 6.1 million pounds. Harvests of all seven major commercially valuable species during 2003 were down relative to the ten-year average.

                Bloater harvest was 1.6 million lbs., but remains nearly 40% of what it was for the period 1985 to 1998.

                During 2003, only 19,000 lbs. of yellow perch were harvested in Wisconsin waters of Lake Michigan. A 20,000 lb. harvest quota is in effect for the commercial fishery, while the sport harvest was reduced to a 10 fish daily bag limit.      The primary tribal fishery in Michigan only netted an estimated 249 lbs. of yellow perch in the 1836 seceded waters, which is a continued decline and the lowest reported harvest for the 18-year period

 

Prey Fish Status and Trends - Using Bottom Trawls

The Great lakes Science Center (GLSC) has conducted lakewide surveys of the fish community in Lake Michigan each fall since 1973. These systematic surveys are performed using standard 12-m bottom trawls towed along contour at depths of 9 to 110 m at each of seven to nine index transects.

                All seven established index transects of the lakewide survey were completed in 2003. Alewife was the most abundant prey fish in Lake Michigan in 2003, with an estimated lakewide biomass of 42.876 kilotonnes (kt). Alewife catch was dominated by the 1998 year-class. Lakewide biomasses of deepwater sculpin, bloater, slimy sculpin, and smelt were estimated at 32.787 kt, 20.682 kt, 2.385 kt, and 1.386 kt. Whereas bloater biomass continued its decline in 2003, alewife biomass has trended neither upward nor downward between the early 1980s and 2003.

                The decline in bloater biomass began in 1990 and can be chiefly attributed to consistently poor recruitment from 1992 through 2003. Smelt biomass declined during 1992-1997, and has remained low since 1997. Deepwater sculpin biomass has shown neither an increasing nor decreasing trend from 1990 to 2003. Burbot abundance decreased during 2001-2003. Slimy sculpin abundance appeared to be leveling off during 2000-2003, following an increase during 1990-2000.

                Yellow perch year-class strength was poor in 2003. Lakewide biomass of dreissenid mussels decreased from 24.464 kt in 2002 to 13.756 kt in 2003. First catch of round gobies in the GLSC lakewide survey of Lake Michigan was recorded in 2003.

 

Abundance

Alewife – Abundance of Lake Michigan adult alewives substantially decreased from 443 fish per tow in 2002 to 163 fish per tow in 2003. Similarly, alewife abundance, on a weight basis, substantially decreased from 11.5 kg per tow in 2002 to 4.9 kg per tow in 2003.

 

Figure 1 – CPE of age-0 alewives in Lake Michigan 1973-2003

 

                Catch of age-0 alewives decreased from 39 fish per tow in 2002 to just 1 fish per tow in 2003. During the 1990-2003 time period, highest age-0 abundances of alewives occurred during 1990, 1998, and 2000 (Figure 1).

                Again, the 1998 year-class appeared to be an exceptionally strong one, as this year-class dominated the catch of adult alewives during 2003. The 1998 year-class also dominated the catch of age-1 and older alewives during 1999-2002 as well.

                Alewife recruitment appeared to be most strongly influenced by predation by salmonines and water temperatures during spring and summer of the alewife’s first year in the lake. Extraordinarily warm water temperatures during spring and summer of 1998 likely led to a moderately high recruitment of age-3 alewives in 2001, despite the high level of salmonine abundance.

 

Bloater – Bloaters are eaten by salmonines in Lake Michigan, although not to the extent that adult alewives are consumed.

                Adult bloaters have decreased in abundance to only 35 fish per tow in 2003, a continuation of a trend of decreasing abundance in this species during the 1990s. The 2003 catch rate represents the lowest value since 1978.

 

Rainbow smelt – Adult smelt abundance decreased from 19 fish per tow in 2002 to 16 fish per tow in 2003. Smelt abundance in 2003 was the lowest on record. Adult smelt abundance declined substantially from 1992 to 1997, and has remained low since 1997. Causes for the decline remain unclear. Consumption

 

Figure 2 – CPE of age-0 smelt in Lake Michigan 1973-2003

 

of smelt by salmonines was higher in the mid 1980s than during 1992-1997, yet adult smelt abundance remained high during the 1980s. Age-0 smelt abundance substantially increased from 13 fish per tow in 2002 to 67 fish per tow in 2003.

 

Sculpins – Slimy sculpin is a favored prey of juvenile lake trout in nearshore regions of the lake. As lake trout grow, the importance of sculpins in lake trout diet decreases substantially so that sculpins form only a minor portion of adult lake trout diet. Deepwater sculpin is an important diet item for burbot in Lake Michigan, especially in deeper waters.

                Catches of deepwater sculpins in Lake Michigan decreased to 176 fish per tow in 2003, compared with 199 fish per tow in 2002. Leveling off of deepwater sculpin abundance during the 1990s coincided with a leveling off of burbot abundance. Catches of slimy sculpins in Lake Michigan increased from 43 fish per tow in 2002 to 64 fish per tow in 2003.

 

Total biomass

It was estimated a total lakewide biomass of prey fish available to the bottom trawl in 2003 of 100.116 kilotonnes (kt) (1 kt = 1000 metric tons.) Alewives constituted 43%, deepwater sculpins 33%, and bloaters 21% of the total prey fish biomass in Lake Michigan in 2003.

                Total prey fish biomass in Lake Michigan has shown a declining trend during 1989-2003, and this decline is mainly attributable to the tremendous decrease in bloater biomass. The current bloater biomass is about 6% of the peak in 1989. Total prey fish biomass did increase slightly between 2000 and 2002, and this slight increase was due to an increase in alewife biomass. Apparently, the 1998 alewife year-class was an exceptionally large one. Nonetheless, alewife biomass has fluctuated with no consistent trend during 1982-2003.

                Long-term trends in alewife biomass suggested that the salmonine stocking program was not only effective in reducing alewife abundance in Lake Michigan, but also effective in maintaining relatively low alewife abundance for the last 20 years. Rainbow smelt biomass declined between 1992 and 1997, and has remained low from 1997 to 2003. Deepwater sculpin biomass has fluctuated without trend during 1990-2003.

Figure 3 – Estimated lakewide biomass of prey fishes in Lake Michigan based on bottom trawl surveys

 

2003 Prey Fish Status  - Using Acoustic Survey Methods

Summary

Beginning in 2001, efforts were initiated to implement a lakewide acoustic survey of prey fish biomass in Lake Michigan. The survey, a cooperative effort between MDNR, WNDR, IDNR, INHS, and USGS, was first completed in 2003. The survey covered an area equivalent to approximately 35% of the lake surface area and consisted of 20 transects, 18 of which were useable in the analyses. In addition to acoustic sampling, midwater trawling (46 tows) was utilized to describe species and size composition of the fish community.

                Young-of-the-year (YOY) ale-wives and smelt made up 95% of total prey fish density, but the combination of alewives and bloaters made up most (66%) of the biomass. Alewife and smelt were of small mean size, with the majority of both populations represented by YOY. Prey fish density was low. Given their low abundance and small size, it is unlikely that the 2003 year class will be a strong one. Due to the small mean size of alewives, lakewide alewife biomass was ~30% of the bottom trawl estimates from lakes Michigan and Huron, but the acoustic estimate was similar to adjusted acoustic biomass values from the late 1990s.

                Bloater catch was evenly split between YOY and yearling-and-older (YAO) fish. Bloater density was variable and low. Lakewide biomass was 12.24 kilotonnes, which was ~60% of the Lake Michigan bottom trawl estimate and 1.65 times the Lake Huron bottom trawl estimate. The 2003 acoustic estimate was also much lower than acoustic estimates in the late 1990s.

                Smelt density was highly variable. Smelt biomass was similar to acoustic estimates from the late 1990s. Acoustically estimated biomass of smelt was ~5 times that of the bottom trawl estimate in Lake Michigan, and ~65% of the Lake Huron bottom trawl estimate. Fish distribution during the survey was strongly influenced by an upwelling event along the western shoreline. Virtually no alewives were captured west of the thermal bar, and bloaters were the most abundant fish in the area of upwelling. The highest total fish density was observed off Ludington, but the highest alewife densities occurred at Good Hart and Little Traverse Bay. Density and biomass estimates exhibited high levels of uncertainty.

                The traditional GLSC prey fish monitoring method (bottom trawl) is inadequate for fish located off bottom. In particular, bottom trawls do not adequately sample young-of-the-year (YOY) alewives and rainbow smelt. Alewives are and have been the primary prey of introduced salmonids in the Great Lakes. Alewife dynamics typically reflect occurrences of strong year classes. Much of the biomass making up a strong year class is not recruited to bottom trawls in its first fall of life, and a great deal of predation by salmonids may be focused on YOY and yearling alewives before they are recruited to the bottom trawl.

                The dynamic nature of the Lake Michigan food web and the potential for high levels of predation of YOY and yearling alewives warrant an increased focus on abundance, distribution, and survival of alewives throughout all stages of life. The primary factors affecting alewife recruitment to age 3 in Lake Michigan have been summer water temperature and predation by salmonids during the spring and summer of the first year of life.

                Recent invasions of exotic species have increased predation pressure on zooplankton and increased competition faced by YOY alewives. In Lake Ontario, predation on zooplankton has resulted in decreased abundance, biomass, and production of zooplankton species important to young-of-year fish and alewives of all ages.

 

Abundance and Biomass

Alewife – Alewife made up 63% of the midwater catch and represented 44% of the prey fish biomass caught. The majority of the alewives caught (76%) were YOY of relatively small size. Approximately 62% of the YOY alewives measured were less than 6 cm in length, and 90% were <70 mm. Previous work in lakes Michigan and Ontario suggested that YOY alewives <60 mm do not survive their first winters. A large proportion of YOY alewives present in September 2003 were not yet of sufficient size to survive their first winter. It is likely that most YAO alewives were from the exceptional 1998 year class, but yearling and older alewives made up a small part of the catch.

Given that the alewife catch was dominated by YOY, this density level suggests the 2003 year class was not a large one.

 

Bloater – Bloater made up only 3% of the catch in numbers, but 49% of the prey fish biomass caught were bloaters. A large proportion of bloaters were YOY, but the mix of ages was more even than that of alewives (44% YOY and 56% YAO).

 

Rainbow smelt – Smelt made up 31% of the catch in numbers and but only 6% of the prey fish biomass caught. Like alewives, the majority of the smelt catch (87%) was made up of YOY fish.

 

Lake whitefish – Whitefish were captured in midwater tows at several locations. They were a minor component of the catch numerically (<1%), but constituted almost 43% of the total biomass caught. Stomach contents of whitefish examined in the field contained primarily Mysis but also included Bythotrephes spines.

 

Sticklebacks Nine- and three-spined sticklebacks made up 3% of the catch numerically and <1% of the total biomass caught. Both species were equally represented in the catch.

 

                Acoustic biomass estimates for both alewives and bloaters were low in comparison with GLSC fall bottom trawl surveys in Lake Michigan. The acoustic estimate of lakewide alewife biomass was ~30% of the lakewide biomass estimated from the Lakes Michigan and Huron bottom trawl surveys in 2003.

                This contrast between the two Lake Michigan surveys was not surprising given that the majority of biomass sampled in the acoustic survey was made up of YOY alewives, while the majority of the biomass in bottom trawls was made up of adult alewives hatched in 1998. These year classes differ in mean weight by at least a factor of 25.

 

Upper Great Lakes Lake Trout Restoration Program

USFWS Data for 2003 and proposed for '04

 

Program highlights included:

·         Stocking of 3.8 million yearling lake trout at 48 Upper Great Lakes locations between April 28 and June 27, 2003;

·         Status of the stocking vessel M/V Togue and the design of the new vessel M/V Spencer F. Baird;

·         Updated information on the Great Lakes Fish Stocking Database; and

·         Updated information on the Wild Fish Health Survey.

 

Facility Updates:

Hatchery Name Change – The name of Hiawatha Forrest National Fish Hatchery (NFH) has been changed to Sullivan Creek NFH to follow the convention on naming hatcheries after their water supply.

 

Hatchery Construction Projects:

Sullivan Creek NFH – A prefabricated metal building has been constructed to cover all raceways which will allow for improved management of fish health and condition at the largest lake trout broodstock facility.

Pendills Creek NFH – A new filtering system for the water supply is being designed and installed to improve the water quality and reduce stress on production fish. Once completed, the existing raceways are scheduled to be replaced and a liquid oxygen system will also be installed.

Iron River NFH – The inflated dome covers are scheduled to be replaced with permanent structures by fall 2004. The risk of the inflated domes collapsing with the potential for significant loss of fish and safety hazard to hatchery staff will be eliminated with the installation of the new structures. A liquid oxygen system has also been installed.

 

Yearling Lake Trout Stocking

Lake Trout Yearlings – 3,817,000 yearling lake trout were released at 48 locations in lakes Superior, Huron and Michigan. Of these, 643,733 were released onshore and 3,173,751 offshore. The M/V Togue began stocking on April 28, 2003 and ended on June 27, 2003, traveling 2,723 miles during the season and stocked fish at 35 sites. The M/V Togue also stocked 100,000 yearlings offshore in Lake Huron for the Michigan DNR. All lake trout were coded-wire tagged and/or fin-clipped following marking guidelines. Distribution included 184,000 into Lake Superior, 1,279,000 into Lake Huron and 2,354,000 into Lake Michigan. All fish stocked met or exceeded the quality targets established for each hatchery.

 

Spring 2004 – USFWS (Service) is preparing to stock approximately 3.75 million yearling lake trout into the Upper Great Lakes this spring, including 1.8 million from Jordan River NFH, 1.2 million from Iron River NFH, and 750,000 from Pendills Creek NFH.

 

Quality vs. Size - The Service recommends that future criteria for lake trout stocked from federal hatcheries focus on fish quality and not on size (number per pound). This recommendation, which has been presented to the Lake Michigan and Huron Technical Committees, is based on a review of the available results from the size/quality-at-stocking studies. Because rearing environments are unique at each hatchery, fish quality targets for visceral fat, eyes, gills, and fins are being developed for each strain at each facility.

 

Lake Trout Propagation Potential – The Service has identified priority maintenance and construction projects at hatcheries necessary to maintain existing capabilities and increase production. These projects include the installation of liquid oxygen and the upgrade of surface water intake structures at each hatchery, the construction of a new raceway building and raceway complex at Pendills Creek NFH, and replacement of 40-year old raceways at Jordan River NFH.

 

Status of the Great Lakes Stocking Vessels 

The Service has received authorization to replace the aging M/V Togue. The new stocking vessel will be named the M/V Spencer F. Baird after the father of all federal fisheries programs dating back to 1873. The M/V Togue is set to stock fish into Lakes Huron and Michigan during 2004. We are hopeful that the M/V Togue will remain operational until the construction of the M/V Baird is completed.

Final design drawings for the M/V Spencer F. Baird are near completion and we anticipate construction to begin in 2004. While we are hopeful that the M/V Baird will be available to stock fish in 2005, it may not be ready until 2006. The M/V Baird will have enhanced stocking capabilities compared to the M/V Togue. It will also have netting capabilities, both trawl and gillnet, to conduct hatchery product evaluation activities.

 

Comparisons of vessels:

M/V Baird                   M/V Togue

Length             95 ft.                        75 ft.

Beam                30 ft.                        22 ft.

Tonnage                        345 tons             98 tons

Cruising

Speed                     14.7 mph                   9.8 mph

Fish Carrying

Capacity                                10 tanks                   8 tanks

Chilled Water

Capacity                                3,490 gal.                  0

Oxygen                  On board               Bottled

System                   system                   oxygen

Ballast Tank

Capacity                                4,220 gal.                   0

Stocking                                                                Vacuum

method                   Gravity                   system

Sleeping

Quarters                                 8                                 2

 

Broodstock Management

Broodstock Production Strains – Yearling lake trout stocked in the upper Great Lakes in 2003 came from seven brood stock strains including: Superior Apostle Island (SAW), Green Lake (GLW), Isle Royale (SIW), Superior Marquette (SMD), Lewis Lake (LLW), Superior Traverse Island (STW) and Seneca Lake (SLW).

 

Broodstock Holding Capabilities – The Service has determined that broodstock facilities in Region 3 can maintain 6-7 production broodstock units. A production broodstock unit is the minimum number of broodstock lines and the minimum number of fish per line that will be maintained for the propagation of yearlings of a given strain for stocking.

The Service will maintain 100 mating pairs in each brood line and use procedures of rotational line crossing and periodic infusion of wild gametes to perpetuate future brood-stock lines. Production broodstock units will be comprised of either two or three brood lines dependent on how readily available wild donor stocks are for broodstock develop-ment. We will maintain two brood lines in a production broodstock unit if donor stocks are readily available and three brood lines if they are not. A two-line production broodstock unit will produce 850,000 yearlings and a three-line unit 1.1 million yearlings.

Of the eight lake trout strains held at Region 3’s broodstock hatcheries, the Green Lake strain is the only strain that wild donor stocks are not readily available and would require a three-line production brood-stock unit. Lake Huron is interested in developing a broodstock of Parry Sound strain, which because of its limited abundance and availability, would likely also require a three-line production broodstock unit.

 

Lake Trout Health

Fish Health Screening – All yearling lake trout lots were tested for pathogens. Additionally, the Service continued a fish health assessment program that was initiated in 2000 in which condition of lake trout and critical environmental factors were monitored from the time fish were taken from the raceway to the time of release.

 

Renibacterium salmoninarum (BK) – Fish health screening showed that R. salmoninarum (causative agent of Bacterial Kidney Disease) was present at low levels in yearling lake trout lots from each of the federal lake trout hatcheries in 2003. All lake trout were of high quality and asympotomatic for BK.

 

Brood Stock Health – Lake trout broodstock held at Sullivan Creek NFH, Michigan and Saratoga NFH, Wyoming continue to be pathogen free. Iron River NFH, Wisconsin broodstock are parenthetical (BK) classification because of the hatchery being positive last year.

 

Great Lakes Fish Stocking Database

The Great Lakes Fish Stocking Database was fully operational in 2003. The database can be viewed at: http://www.glfc.org/fishstocking/index.htm.

 

2003 Sea Lamprey Management

Tributary Information

·         Lake Michigan has 511 tributaries

·         121 tributaries have historical records of sea lamprey larvae production.

·         63 tributaries have been treated with lampricide at least once during 1994-2003.

·         Of these, 32 tributaries are treated on a regular 3-5 year cycle.

 

Lampricide Control

The following statements highlight the lampricide control program during 2003.

·         Treatments were successfully completed on 14 scheduled streams.

·         Treatments of the Pentwater and Platte rivers were completed to reduce populations of residual sea lampreys.

·         The protocol for application of lampricides to streams with populations of young-of-year lake sturgeons was followed for treatments of the Manistee and Manistique rivers. Maximum application rates of lampricides were limited to 1.2 times the minimum lethal concentration to protect juvenile lake sturgeons. The lake sturgeon is listed as a threatened species in Michigan.

·         The Manistique River upstream of the Manistique Papers, Inc. dam was treated for the first time since 1974; the 2003 treatment was much more extensive than the previous treatment.

·         Treatments of backwaters and bayous of the Manistee River were coordinated with the mainstream lampricide application. This was an effective strategy to reduce survival of sea lampreys.

·         A total of 14,832 spawning-phase male sea lampreys were transported to the sterilization facility at the Hammond Bay Biological Station from trapping operations on the Manistique River (13,391) and Peshtigo River (1,441). At the facility sea lampreys are sterilized with the chemosterilant bisazir.

 

Barriers

At the end of 2003, 15% of larval habitat has been excluded from production by 69 barriers that have been constructed or modified to block sea lampreys on tributaries of the Great Lakes.

                New construction projects of sea lamprey barriers are in various stages of development on the Cedar, Paw Paw, Galien, Carp Lake, and Manistique rivers and Trail and Kids creeks.

 

Assessment

Tributaries considered for lampricide treatment during 2004 were assessed during 2003 to estimate larval density and amount of suitable larval habitat. After the data were processed, tributaries were ranked for treatment during 2004 based on an estimated cost per kill of metamorphosed sea lampreys.

·         Assessments of populations of sea lamprey larvae were conducted in 67 tributaries and offshore of 8 tributaries.

·         Populations of larvae were estimated in 33 tributaries.

·         A post-treatment quantitative assessment was conducted in the Little Manistee River, which was subsequently scheduled for lampricide treatment during 2004.

·         Mark-recapture larval population estimates were conducted on 4 stream reaches to verify habitat-based larval population estimates.

·         A sampling and catch-per-unit-effort sampling was conducted in two stream reaches as part of a larger project to test a potentially more efficient sampling method for larval assessment.

·         Quantitative larval assessment sampling was optimized in a subset of Lake Michigan streams surveyed during 2003. The number of density samples collected from each type of larval habitat (preferred or acceptable habitats) was allocated on the basis of optimization rules developed from previous annual measures of larval population density sampling and habitat variances in those reaches.

 

Spawning-phase

The long-term effectiveness of the control program has been measured by the annual estimation of the lakewide abundance of spawning-phase sea lampreys. Lakewide abundance has been estimated since 1986 from a combination of mark-recapture estimates in streams with traps and model-predicted estimates in streams without traps.

·         36,537 sea lampreys were captured at 17 sites in 15 tributaries during 2003.

·         The estimated population of spawning-phase sea lampreys for 2003 was 118,805.

·         Spawning runs were monitored in the Boardman and Betsie rivers through a cooperative agreement with the Grand Traverse Band of Ottawa and Chippewa Indians and in the Carp Lake Outlet with the Little Traverse Bay Band of Odawa Indians


 

Lake Erie Fishery Review - continued

Catch Limits Set

continued from page1

growth will be sustained and contribute to a more robust, stable walleye fishery, starting in 2005.

                "The Lake Erie Committee has had a challenging year managing the walleye fishery,” said committee chair Rick Hoopes, PFBC fish chief. “While we are very optimistic because of the strong spawning in 2003, we all agree that we must take steps this year to protect the future of the fishery. We are very pleased with the cooperation among the jurisdictions on the lake and with the dialogue that has taken place between the management agencies and the affected stakeholders.”

                The annual TAC, established by the LEC is allocated to Ohio, Michigan and Ontario by an area-based sharing formula of walleye habitat within each jurisdiction in the western and central basin of the lake. The walleye fisheries of eastern Lake Erie remain outside the quota management area.

 

Yellow Perch

Yellow perch was strong in 2003 ― and looks strong in 2004 ― such that the Committee agreed to an 11% increase in the total allowable catch (TAC), from 9.9 million lbs. in 2003 to 11 million lbs. this year. An area-based sharing formula determines the allocation of these fish among the five jurisdictions on the lake. For '04, Ontario’s share is about 5.2 million lbs. and Ohio’s allocation is 5.1 million lbs. Michigan, New York, and Pennsylvania share the remaining allocation. In 2003, all jurisdictions experienced excellent sport and commercial yellow perch fishing (Table 1). As with walleye, the yellow perch spawning in 2003 was one of the best on record.

 

2004 Yellow Perch Projection

Overall, projected 2004 yellow perch abundance (2+) was 38%, 45%, 41%
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