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Highlights of Great
Lakes Fishery Commissions Lake Committee meetings
for Lake Michigan, Lake Huron and
Lake Superior
Lake
Michigan
Harvest of Fishes lakewide
General
Pounds of fish
harvested are estimated for 22 species from commercial fishing, sport
fishing, weir harvest, assessment surveys and incidental catch by the
commercial fishery.
The total
biomass of fish harvested in 2001 was 17.0 million lbs. The peak harvest
(1985 to present) was 56.5 million lbs in 1985. Harvest averaged 43.8
million lbs from 1985 through 1991, and 21.6 million lbs from 1992 to
present, with a general downward trend, primarily driven by trends in
the commercial fishery.
The bulk of
harvest reduction during the early 90s is due to closure of the
commercial alewife fishery and a reduction in Chinook harvest. Harvest
levels since 93 have been within sustainable harvest limits of 12.2 to
25.4 million lbs, as outlined in the Fish Community Objectives for Lake
Michigan.
Benthivore
harvest is dominated by Lake Whitefish, and commercial fishing is the
primary source of harvest. Total benthivore harvest of 4.3 million pounds
during 2001 was the lowest for the 16-year period and 47% below the
average for that period.
Salmon harvest
The salmonid
harvest of 10 million lbs during 2001 continued an increasing trend since
hitting a low of 6.1 million lbs during 1992. This is the first time since
88 that harvest has reached the 10 million lb level. Salmonid forage
appears to be plentiful. Lake trout harvest was the lowest during the 16
year period, at 1.3 million lbs. Only 13% of the salmonid harvest was made
up of lake trout, due in part to an increased availability of other
species. Chinook harvest reached 5.7 million lbs, the highest level since
1988.
Coho salmon
and brown trout dropped slightly from the 2000 levels. Steelhead trout
have decreased since record levels in 1998, however, during 2001 harvest
surpassed all years with a record 1.3 million lbs. Most jurisdictions
enjoyed tremendous steelhead fishing in the Lake. Indiana, however, had
harvest levels below most previous years. Weather conditions, low lake
water levels as well as availability of other salmonid species in southern
Lake Michigan likely contributed to this.
Walleye harvest
The
harvest of inshore fishes was within the target range of 2.2 to 4.4
million lbs from 1985 to 1995, but has remained well below since. Harvest
was .76 million lbs, a slight increase over 2000. Except for 1994 through
1996, walleye were below the target of 0.2 to 0.4 million lbs for the
16-year period.
Commercial harvest
Commercial
harvest has been stable over the 16-year period, and whitefish provided
the bulk of the fishery in recent years. Whitefish harvest reached a
record low of 4.3 million lbs, a decrease over last year of 4.8 million
lbs. Harvest of other species was in a downward trend during the 90s, due
to declining harvest of smelt, yellow perch and bloaters, and more
recently, Lake Whitefish. The estimated harvest during 2001 was a record
low of 6.3 million lbs, compared to an average of 13.4 million lbs since
1992.
Harvests of all seven major commercial species were down relative to the
ten-year average. Bloater harvest continued to decline to only 42% of the
ten-year average. Commercial harvest of yellow perch averaged 3.2 million
lbs from 1985 to 1996, but is currently suspended in most jurisdictions,
and declined by 95%, based on the 10 year average in jurisdictions where
commercial fishing continues.
Stocking
Summaries-1976-2001
Lakewide Trends:
The number of trout and salmon stocked totaled 12.9 million fish, which
was 49,000 fewer fish than last year, and 1.6 million less than the long
term average of 14.5 million. It was one of the lowest levels since 1977.
Total stocking peaked at 17.3 million fish in 1984.
Chinook Salmon decreased to 4.2 million fish, about 200,000 fewer fish
than 2000. Wisconsin and Indiana stocked more Chinook salmon and Michigan
and Illinois stocked fewer than in the previous year. Annual stocking has
ranged from 2.8 million fish in 77 to 6.4 million in 95.
Coho Salmon
increased to 2.8 million, 100,000 more than 2000. Numbers increased
slightly in Wisconsin and Michigan, decreased in Illinois, and stayed the
same in Indiana.
Rainbow Trout/Steelhead
increased from 1.5 million in 2000 to 1.8 million in 2001, and was due to
an increase in stocking by Wisconsin, Michigan and Indiana.
Brown Trout
decreased from 1.8 million fish in 2000 to 1.7 million in 2001. Wisconsin
continues to stock the majority (71%) of brown trout.
Brook Trout:
All 90,000 brook trout were stocked in Wisconsin waters, which was 70,000
fewer fish than in 2000.
Splake:
Only Michigan and Wisconsin stocked Splake, 104,000 fish, a decrease from
115,000 stocked last year.
Lake Trout:
There were 2.3 million lake trout stocked, which was the same number
stocked in 2000. All fish were reared to an average size of 12.7 fish/lb.
Lake Trout Stocking
Strategies
The last
native lake trout were observed in Lake Michigan in 1954 shortly before
they were extirpated from overfishing and sea lamprey predation. Stocking
hatchery-reared lake trout to restore populations began in 1965 after
effective sea lamprey control had been initiated, and with the
implementation of a lake-wide rehabilitation plan approved by the Lake
Michigan management agencies.
The stocking strategy directed lake trout to be stocked by boat over
historically important spawning reefs with the expectation that this would
expedite colonization. Since 1985, more than 80% of the lake trout stocked
have been transported and released directly above 24 specific spawning
reefs, compared to less than 27% in previous years
Heretofore the efficacy of stocking hatchery-reared lake trout directly on
spawning sites has not been examined in Lake Michigan, or elsewhere in the
Great Lakes. The ability of hatchery-reared lake trout to home back to the
stocking site at sexual maturity has been questioned. Hatchery-reared lake
trout have survived well, become abundant enough to support fisheries, but
have developed only a few significant spawning stocks on specific reefs.
Spawning stocks of multiple age groups have only recently become
established in many areas routinely stocked in northern Lake Michigan and
require evaluation.
The objective was to determine how effective site-specific lake trout
stocking is to re-colonizing historically important spawning reefs in Lake
Michigan.
This
project was funded by the Great Lakes Fishery Trust to examine spawner
density on reefs in northern Lake Michigan as these were historically
important areas for reproduction. We measured abundance of lake trout
spawners at 46 onshore and offshore reefs in fall of 1999-2001. Reefs were
grouped into four classes by stocking history and proximity to the
shoreline: stocked/onshore, stocked/offshore, not stocked/onshore, and not
stocked/offshore.
Abundance of lake trout spanners ranged from 0 fish/1000 ft. at hog Island
Shoal, middle Ground, and whaleback Shoal to 142 fish/1000 ft. at
Sheboygan Reef. Only 11 sites of 46 had CPUEs above 50/fish 1000 ft.,
which appears to be an average minimum density at which reproduction was
observed. Comparison of spawner CPUE in lake Michigan with similar data
from Gull Island Shoal, Lake superior (223 fish/1000 ft), a site with a
self-sustaining population, indicates that densities are well below those
recorded there. These results suggest that spawner abundance may not be
adequate at many sites in Lake Michigan.
Age of
lake trout spawners indicate that the mean age at most sites was <7 years.
Previous studies have shown that age of maturity in Lake Michigan occurs
at age 7. In comparison, reefs in Lake Superior that provide natural
recruitment have parental stocks with mean ages of 12 yrs. or older and
are made up of 20-25 age groups compared to 5-15 age groups in Lake
Michigan.
Lake Trout Rehabilitation
Lake trout
rehabilitation is a joint effort involving State, Federal and Tribal
governments. Number stocked was 2.381 million yearlings. Yearlings
stocked since 95 are larger (10-12 per lb) compared to historic size (20
per lb) stocked.
Stocking
Lake trout
stocked in the Northern Refuge fell 1.4% short of the stocking goal of
450,000 and consisted of Lewis Lake, Apostle Island, and Isle Royal
strains. Stocking in the Midlake Refuge exceeded the stocking goal of
300,000 by 1.7%. As in previous years, fish stocked were of two strains:
the Green Lake and Seneca. All yearlings stocked in the two refuges are
part of a strain evaluation experiment and consequently, all are
coded-wire-tagged (CWT) and adipose finclipped.
Stocking in the primary and secondary zones exceeded the stocking goals of
680,000 and 540,000 fish, by 22.3% and 48.7%, respectively. The increase
is due in part to the surplus of lake trout available from the reduced
demand in Lake Superior, where natural reproduction has occurred and
reduced demand for stocking of yearlings. The Lewis Lake strain and Green
Lake strain yearlings stocked at Juliens Reef were coded-wire-tagged and
adipose finclipped. The rest of the yearlings were marked with a RPLV
finclip. A variety of lake trout strains were stocked in the primary and
secondary zones and consisted of the Marquette, Green Lake, Seneca Lake,
Lewis Lake, Apostle Island, and Isle Royale strains.
Assessment
Agencies implemented a
coordinated lakewide spring assessment in 1998, the objective being to
develop a standardized protocol on population data. Catch rates for all
16 sites fished in 2001 varied substantially and ranged from 0.5 at
Manistique to 26.2 at Arcadia. In addition to Manistique, comparatively
low CPEs were found at Gull Island Reef and Old Mission Point, where both
were below 5.0. Total CPEs at the majority of the other sites sampled (9
of the total 16) ranged between 5.0 to 15.0.
After Arcadia, highest catch rates occurred at Clay Banks, Manistee and
the East Reef, all of which had total CPEs above 15. The highest CPE of
age 7+ and older fish was found at Clay Banks (7.8). Catch rates of age 7+
and older fish ranged between 3.3 to 4.0 at Arcadia, Sheboygan, and
Waukegan, while the catch rate of older age fish ranged between 1.3 to 3.0
at Ludington, Manistee, Lee Point, the East Reef, Leland, and Michigan
City. Lowest catch rates of age 7+ and older fish were found at Little
Traverse Bay, Boulder Reef, Old Mission Point, Saugatuck, Gull Island
Reef, and Manistique.
CPEs generally were highest in 2001 in the middle of Lake Michigan. Total
annual mortality varied from a low of 32% in the West Shore Region to a
high of 59% in the East Shore Region. Total annual mortality of 40% or
less is an objective identified in the lake trout rehabilitation plan.
Annual mortality estimates in five of the seven regions was at or below
this goal.
Little
Traverse Bay and Old Mission Point had catches of lake trout with
unclipped percentages above or near the established background level of
5.0%.
Sea Lamprey Management
In the past
decade the USFWS & DFO have reduced the dependency on TFM through the
development and implementation of alternative controls, the refinement of
assessment procedures, and improvement of application techniques to more
efficiently treat tributaries. The use of TFM has decreased from an annual
average of 49,406 kg. during 80-89 to an annual average of 35.377 kg.
during 92-01.
Treatment of tributaries over the years has provided sufficient control of
sea lampreys, yet increases in lamprey wounding rates on lake trout in
northern waters of the lake are a concern. The refuges and primary zones
where priority should be given to control lamprey populations include the
mid-northern region of the lake, the mid-lake reef zone, and an offshore
reef area in the southwest portion of the lake.
Tributary Information
·
Lake Michigan
has 511 tributaries.
·
121
tributaries have historical records of sea lamprey larvae production.
·
65
tributaries have been treated with lampricide at least once during
1992-2001.
·
Of these, 35
tributaries are treated on a regular 1-5 year cycle.
FWS & DFO treatment units
administer and monitor doses of the lampricide TFM, sometimes augmented
with
Bayluscide 70%
Wettable Powder, to scheduled tributaries. In recent years, personnel have
reduced the amount of lampricide used by about 30%.
·
Treatments
were completed successfully in all 19 scheduled tributaries.
· The
interim protocol for application of lampricides to streams with
populations of young-of-year lake sturgeons was followed in treatments of
the Peshtigo, Oconto, Whitefish, Manistique, Cedar, and White rivers. The
protocol limits the concentrations of TFM and Bayluscide 70% Wettable
Powder to 1.2 times minimum lethal concentration (MLC; lampricide
necessary to kill 99.9% of sea lampreys in a 12-hour treatment) to protect
young-of-year lake sturgeons in the tributaries.
· No
significant mortality of non-target organisms occurred during any
treatment.
Alternative Controls
Sterile Male Release
Technique
Research into
the sterile male release technique for lamprey control began during 1971.
The technique was experimentally implemented in Lake Superior tributaries
and the St. Marys River during 1991-1996. Lampreys are now released
exclusively in the St. Marys River to enhance control.
Male lampreys
are captured during their spawning migrations in 20 tributaries to Lakes
Superior, Michigan, Huron, and Ontario and the St. Marys River and
transported to the sterilization facility at the Hammond Bay Biological
Station. Sea lampreys are sterilized with the chemosterilant bisazir,
decontaminated, and released into the St. Marys River. Laboratory and
field studies have shown that treated male sea lampreys were sterile and
sexually competitive, and that the number of eggs that hatch was reduced.
·
A total of
11,568 spawning-phase male sea lampreys were transported to the
sterilization facility from trapping operations on the Manistique (10,879)
and Peshtigo (689) rivers.
Barriers
Barriers
are currently the only proven alternative control method. Presently, there
are 12 purpose-built sea lamprey barriers on Lake Michigan tributaries.
·
Kids Creek (Boardman
R.) barrier project continued with initiation of the Planning, Design and
Analysis phase.
·
Pere
Marquette River The electrical weir with its pumped-source pool and weir
fishery was operated for the second season. A total of 11,044 fish (4,805
steelhead, 3,205 white suckers, 2,857 redhorse suckers and 177 brown
trout) were counted, identified and returned to the river upstream of the
barrier. Personnel estimated the efficiency of steelhead passage at ≥67%.
·
Paw Paw River
The Commission began to negotiated terms of the Project Construction
Agreement for the inflatable barrier and fishway.
·
Rapid River,
Carp Lake River, South Branch Galien River and Trail Creek The Corps
completed Preliminary Restoration Plans for proposed barrier projects on
each of these streams.
·
Cedar River
A barrier project was initiated under administration of the FWS
·
Days
River An automatic water level recording device was installed on the
Days River barrier as part of an effort to evaluate performance of
existing barriers relative to crest height and barrier design. The Days
River barrier has successfully blocked lampreys since construction in
1983.
Assessment
·
Counts of
lamprey larvae populations were conducted in 55 tributaries and offshore
of 4 tributaries.
·
29,260 sea
lampreys were trapped at 17 sites in 15 tributaries.
·
Spawning-phase sea lampreys population was 91,310.
The MI
&WI DNRs reported 519 sea lampreys were collected; 292 were attached to
lake trout and 227 were attached to Chinook salmon. Lampreys were attached
at a rate of 1.05 per 100 lake trout and 0.3 per 100 Chinook salmon.
Status of Yellow Perch in
Lake Michigan
General
Yellow perch
assessment activity is occurring throughout the lake, with numerous agency
and university personnel sampling perch utilizing various gear types in
different seasons. Coordinated regulation of yellow perch harvest has been
an important part of perch management in recent years.
Data shows a long-term decline in adult yellow perch abundance. The longer
data series show peaks in the mid-1980s to early 1990s, followed by
significant declines through the mid-1990s. Adult perch numbers have
leveled out or increased slightly in some jurisdictions in recent years.
Fluctuations in adult abundance have been accompanied by changes in the
composition of the catch by sex.
Adult
population has been measured annually and minor variability in all
collections documented that fish from a single dominant 1998 year class
account for the majority of adult population.
2002 Yellow Perch Harvest
Restrictions
Sportfishing
regulations:
w
Illinois
w
Indiana
w
Michigan
w
Wisconsin (Lake Michigan)
w
Wisconsin (Green Bay)
March 16 through May 15; closed to sportfishing for
yellow perch
Daily bag limit 10 fish
Commercial regulations:
w
Illinois perch fishery closed
w
Indiana perch fishery closed
w
Michigan no commercial harvest (outside of 1836 Treaty
waters)
w
Wisconsin perch fishery closed (outside of Green Bay, where
quota is 20,000 lbs)
2001
is the fifth year of the lakewide research initiative implemented by the
Lake Michigan Management Agencies. The goal of this effort is to identify
likely causes for the lack of perch recruitment in the early1990s. A draft
5-year report describing this work (Yellow Perch Research and
Management in Lake Michigan: Evaluating Progress in a Cooperative Effort,
1997-2001) is available from the Lake Michigan Yellow Perch Task
Group chairperson.
Wisconsins Sportfishing
Effort
Fishing
effort, harvest and harvest rates were determined from 1) random creek
survey of launched-boat, pier, shore and stream anglers; 2) mail survey of
moored-boat anglers; and 3) mandatory charter-boat reporting. Anglers
spent an estimated 2,740,250 hours fishing on Lake Michigan and Green Bay
during 2001 with boat-anglers effort at 1,903,517 hours or 69% of the
total hours.
The harvest of 774,057 fish was dominated by yellow perch (339,769),
Chinook salmon (191,378), rainbow trout (72,854) and Coho salmon (47,474).
The boat fishery dominated the fishery by harvesting an estimated 612,207
fish which was 79% of the total harvest and was dominated by yellow perch
(255,003), Chinook salmon (155,149), rainbow trout (64,009) and Coho
salmon (45,403). Overall harvest-rates were highest for yellow perch at
0.1240 fish/hour and Chinook salmon at 0.0698 fish/hour.
Fishing effort showed a slight increase over 2000, but was 9% below the
ten-year average. Effort was 30% below the average in Green Bay, but less
than 0.2% below the average in Lake Michigan. Despite the decline, Green
Bay anglers had the most fishing effort at 668,297 hours or 24% of all
angler hours for 2001. Milwaukee anglers were second at 360,474 hours.
Harvests
Anglers
harvested 378,798 salmonids, with Chinook salmon dominating the 2001
salmonid harvest, comprising 191,378 fish or 51% of the total. This was
the highest Chinook harvest since 87, but harvest of other salmonids was
below average. Rainbow trout harvest was 2nd to Chinook at
72,854, 19% of the total. Coho harvest was 47,474 fish or 13% of the
total. Lake trout harvest was 40,408, 11% of the total. Brown trout
declined to 7% of the harvest at a record-low 26,421, followed by brook
trout at 263. The combined harvest-rate for salmonids of 0.1382 was lower
than the record 0.1625 posted during 2000, but was similar to the ten-year
average of 0.1376.
Anglers harvested 206,109 yellow perch in Green Bay, continuing a
long-term decline. The harvest rate was 0.3084 fish/hour. Lake Michigan
anglers harvested 133,660 yellow perch and had a harvest rate of 0.0645
fish/hour. Yellow perch were the most numerous species harvested for the
boat, pier and shore fisheries. As usual, the majority of the harvest
(75%) was from boats, but pier and shore harvests increased substantially
over recent years. The pier fishery had the highest general harvest rate
for perch at 0.2321 fish/hour, with the majority of the harvest June to
September.
Perch harvest continued a pattern of increase since 1997, but remained
well below the ten-year average of 790,532. The Coho harvest of 47,474 was
the lowest of the ten-year period and 42% below the ten-year average.
Overall Coho salmon harvest-rates were 0.0173. Boat anglers harvested 96%
of all Coho salmon (45,403) and had a harvest rate of 0.0239.
Anglers harvested 191,378 Chinook salmon, the highest since 1987 and 38%
above the ten-year average of 138,933. The overall harvest-rate was 0.0698
fish/hour. Boat anglers harvested 155,149 fish or 81% of all Chinook.
Boat-angler harvest rates were 0.0815. Pier, shore and stream anglers also
saw strong harvests of Chinook, primarily during the fall run. Average
weight and length for Chinook salmon were the highest of the last ten
years, at 13.1 lbs and 31.0 inches.
Rainbow trout contributed strongly to the salmonid fishery. Harvest was
lower than average but similar to 2000 levels. Rainbow trout were the
second-most abundant salmonid and third-most abundant species harvested
during 2001 at 72,854 fish. The majority (88%) of the harvest occurred in
the boat fishery with 64,009 fish. Stream anglers harvested 6,378
steelhead with a harvest rate of 0.0161 fish/hour. Rainbow trout were
similar in size to the ten-year average, at 6.9 pounds and 25.7 inches.
However, the standard weight of a 22-inch rainbow was equal to 4.4 lbs,
the highest standard weight of the last ten years.
Wisconsin anglers harvested 40,408 lake trout in Lake Michigan, 30% above
the record low of 2000, but still 23% below the ten-year average of
52,555. The overall harvest-rate was 0.0147 fish/hour. Boat anglers
harvested all but 72 lake trout with 40,336. The boat harvest-rate was
0.0212 fish/hour. Lake trout average size was 8.8 lbs and 27.7
inches.
26,421 brown trout were harvested with an overall harvest-rate of 0.0096
fish/hour. This was a record-low harvest, 39% below the ten-year average.
The decline is mainly attributable to a low harvest of 13,778 brown trout
by boat anglers. Brown trout biological data was the highest of the past
ten years, with a mean size of 7.2 lbs, 23.5 inches.
Smallmouth bass harvest has declined steadily since 1997 and was the
lowest of the last ten years, 53% below the average at 17,723 fish.
Overall harvest-rates were 0.0065 fish/hour. Again, boat anglers harvested
the majority of the smallmouth bass, with 15,101 fish or 85% of the total.
Walleyes were the last species harvested in large numbers during the
open-water fishing season, with 25,038 walleyes taken. This is consistent
with recent years after a low harvest of 11,319 during 2000. Like
smallmouth bass, walleye harvest-rates were lower than most salmonids at
.0091 fish/hour. Boat anglers harvested 17,215 walleyes, while stream
anglers harvested 6,555.
The remaining species, brook trout, Splake and northern pike, comprised
les than 0.5% of the total harvest.
Summary
Lake Michigan
anglers spent an estimated 2,740,250 hours fishing on Lake Michigan and
Green Bay with boat-anglers effort of 1,903,517 hours or 69% of total
hours. The harvest of 774,057 fish was dominated by yellow perch (339,769)
and to a lesser degree by Chinook salmon (191,378) and rainbow trout
(72,854).
Fishing effort was 21% higher than the record low observed during 2000,
but still 9% below the ten-year average. Green Bay was 30% below the
average and Eastern Door County was 18% below.
Mean
lengths and weights of salmonids were generally above average, most
notably for brown trout weight (+29%) and Chinook weight (+24%) but
standard weights were similar to the ten-year averages except for rainbow
trout. Harvest of all salmonids except Chinook was below average, but
Chinook harvest was the highest since 1987. Harvest of smallmouth bass
continued a downward trend, while walleye harvest was 12% above average
following a poor year during 2000. Perch harvest, although greatly
reduced, compared to the early 1990s, appears to be stable or slightly
decreasing on Green Bay.
Wisconsin Weir Harvests
The WDNR
operates three salmonid egg collection stations on Lake Michigan
tributaries: The Strawberry Creek Weir (SCW), the Buzz Besadny Anadromous
Fisheries Facility (BAFF) on the Kewaunee River, and the Root River
Steelhead facility (RRSF).
During the fall of 2001, 8,125 Chinook salmon weighing an estimated
119,438 lbs were processed at SCW. This was a record harvest despite the
low stream flow and low lake level. The Chinook salmon return to BAFF was
up dramatically to 5,092. No Chinook salmon eggs were collected at BAFF as
the full Chinook egg quota was collected at the primary Chinook facility (SCW).
The Coho salmon return to BAFF in the fall of 2001 was 175, an all time
low and is well below the eleven year average of 2,033. Approximately
123,000 Coho eggs were collected at BAFF.
The steelhead return to BAFF was 426, with the majority returning in the
spring as Chambers Creek and Ganaraska strains, and was the second lowest
steelhead return. During the previous nine years an average of 2,102
steelhead have been processed each year. About 269,000 steelhead eggs were
collected at BAFF.
A
record number of 10,213 Chinook salmon were captured at the RRSF. The
majority of the Chinook (9,697 or 95%) were passed upstream, as all
Chinook eggs were collected at SCW.
Steelhead return at RRSF in 2001 was 1,349. Most of these steelhead (859
or 64%) returned in the spring and were likely either Chambers Creek or
Ganaraska strain. The steelhead returning in fall (490 or 36%) were
primarily Skamania strain. Approximately 800,000 steelhead eggs were
collected at RRSF in spring 2001.
Commercial Fishery
Chub Fishery
The total
reported chub harvest from the commercial gill nets was 1,077,703 lbs, an
increase of 13% from 2000. Smelt trawlers harvested an additional 266,169
lbs incidental to the targeted smelt harvest. Of this take, 43,854 lbs
were sorted as marketable catch and 222,315 lbs were unsorted.
Whitefish fishery
The reported
commercial harvest of lake whitefish from the Wisconsin waters of Lake
Michigan was 1,616,198 lbs.. The total annual quota of whitefish for
commercials was increased four times since it was first established at
1.15 million lbs in 1989-90 and is currently at 2.47 million lbs.
Whitefish CPEs for Wisconsin commercial fishermen in Lake Superior during
the months of May, June, July, and August dropped 36%, 60%, 69% and 39%
respectively from 96 to 98, due to the movement of whitefish to deeper
waters. Based on preliminary analysis, the WDNR has initiated a rule
change proposal, which will permit the use of trap nets to depths of 150
ft. Whitefish mean length and weight at age (ages 2-5) were near the
lowest documented since 1985. As a result, the age at which whitefish are
recruited to the commercial fishery has increased from age four to age
five.
Smelt Fishery
Targeted
rainbow smelt harvest quota for the waters of Lake Michigan and Green Bay
was set at 2.358 million lbs, of which no more than 830,000 lbs could be
caught in Green Bay. During 1999, the total harvest quota was reduced to 1
million lbs, of which no more than 351,993 lbs could be harvested from
Green Bay. The harvest of smelt from Lake Michigan was 234,505 lbs, the
lowest reported since 86 when 239,340 lbs was harvested. Trawlers on
Green Bay reported a rainbow smelt catch of 11,665 lbs, the lowest ever
reported. CPE on Green Bay decreased 35% from 2000 levels. Sharp declines
in smelt harvest and CPE in 2000 and 2001 indicate that lakewide smelt
numbers remained depressed from past levels. |
Green Bay Walleye
The adult
spawning population of walleye in the Fox River was estimated at 16,492,
with levels for the past three years remaining stable but substantially
lower than the ten year average of 27,700 adults. Continued low water
levels on Green Bay have compromised the ability to set nets in
appropriate locations. It was estimated that 1,663 male walleye were
recruited to the spawning population in 2001, far short of expectations.
Age three class dominated the male spawning population in 2000,
representing 48.7% of all males, but age three males represented only
20.5% of the male population in 2001.
The
walleye catch of Green Bay was estimated at 55,700 walleye during the open
water season, down from 81,500 in 2000. Brown and Marinette Counties
showed a reduction in catch, while Door/Kewaunee and Oconto County showed
an increase. In contrast, total harvest on Green Bay more than doubled,
increasing from 10,945 walleye in 2000 to 24,193 in 2001, with most of the
increase occurring in Marinette County waters where the harvest almost
tripled from 8,511 walleye to 22,937.
Sturgeon Bay Walleye
The
predominance of 6-year-old females, similar to males, also suggests good
survival from the stocking in 1994. As with males, females from age 7
through 14 originated from natural reproduction or emigration into the
area. Females ranged in length from 18 to 31. Most females were
visually mature by the age 4. A population of 4,428 walleye was estimated
to be in these waters during the spring spawning period. The number of
sexually mature males was estimated to be 3,011.
Lake Huron
Lake Trout
Rehabilitation
Stocking of
hatchery-reared lake trout was initiated in Lake Huron in 1973 following
the implementation of sea lamprey control. Beginning in 1992,
and again in 94, 96, and 98, additional lots of Lewis Lake fish were
stocked in the nearshore waters of western Lake Huron. All fish were fin
clipped and implanted with CWT.
Genetic Strains
Historically,
as many as 12 sub-populations or strains of lake trout stocks may have
inhabited Lake Huron, each reflecting various degrees of adaptation to
their local environment. However, with the exception of two remnant stocks
in Georgian Bay, these variations have been lost forever. Restoration
efforts over a 12-year period using Marquette-Superior lake trout failed
to establish stocks of naturally reproducing trout. At present, the
performance of five strains of lake trout is being monitored as part of
the lake trout restoration program.
The Marquette-Superior strain or lean lake trout is native to the cold
deep waters of Lake Superior. This strain was selected to serve as the
standard with which to compare the performance of the other strains.
Sixteen consecutive year-classes (1985-2000) of Marquette-Superior trout
have been stocked in Lake Huron.
Two federal brood stock programs were developed: first, the Jenny Lake
program at Jackson Hole, Wyoming NFH, and the Lewis Lake program at
Saratoga, Wyoming NFH. When the Jenny Lake brood stock became infected
with BKD and were destroyed in 1990, no effort was made to replace this
strain. In 1989, the Lewis Lake brood stock matured at Saratoga NFH and
began to supply eggs for the Program (1989-2001 year-classes).
Lake trout from Seneca Lake, NY, were also included in the program in an
attempt to inject lamprey resistant strains into the system. Lake trout in
Seneca Lake have coexisted with lamprey for centuries. Moreover, the
Seneca Lake strain had been successfully stocked in Lake Champlain, NY in
the early 60s where they have survived and reproduced in the presence of
lamprey.
Until recently, the availability of Seneca Lake strain fish was not
adequate to meet all the needs in the upper and lower Great Lakes and
impacted the strain experiments in Lake Huron. Fortunately, Pendills
Creek/Hiawatha NFH has developed a disease-free brood stock that is now
producing eggs and should meet all existing needs for Seneca Lake fish in
Lake Huron.
The Lake Ontario strain of lake trout was developed from Lake Ontario lake
trout in the mid-1980s. Testing of the Lake Ontario brood stock has shown
some genetic contamination. Only three year-classes (89, 91 and 92) of
Lake Ontario strain lake trout were stocked in the lake. Through 2001,
2,509,918 CWT tagged lake trout have been stocked on Six Fathom Bank, and
379,258 Seneca Lake lake trout (2000 year-class) were stocked on Yankee
Reef, with 216,895 of the total receiving a CWT.
Stocking on the Drummond Island Refuge was a provision of the 1985 Consent
Agreement between the Tribes, Michigan, feds and angling groups. Since
1985, a total of 1,841,222 coded-wire tagged lake trout have been stocked
at this site.
Coded-Wire Tag Recoveries
In total,
1,385 coded-wire tags were recovered in 2001 from fish stocked in water of
Lake Huron since 1985. A few 16-year-old lake trout from the 1985
year-class stocked at Six Fathom Bank are still present in the
catch.
In 2001, the 95 and 97 year-classes of Lewis Lake lake trout were well
represented in the catch. Marquette-Superior (1997 and 1998 year-classes)
and Seneca Lake (1995, 1996, and 1997 year-classes) lake trout also
contributed substantially to the set of coded wire tagged lake trout
caught.
353
coded-wire tags were recovered in 2001 from lake trout stocked at Six
Fathom Bank since 1985.
374
coded-wire tags were recovered in 2001 from lake trout stocked in the
Northern Refuge since 1985.
The 1995 and 1997 year-classes represented 47.9 and 43.6% of the 2001
catch from the nearshore movement study. In 2001, 2,058 coded-wire tags
were recovered from lake trout stocked for the nearshore movement study.
Assessment
Since June
1986, the Great Lakes Science Center has conducted spring assessments of
lake trout, burbot, and prey fish stocks in the Six Fathom Bank lake trout
refuge, having caught 193 lake trout during 2001. 124 had an adipose fin
clip, and 116 CWTs were recovered from Six Fathom Bank lake trout.
Offshore sea lamprey wounding rates, regardless of age, were 11.1 for
Lewis Lake, 13.8 for Marquette-Superior, 0.0 for Lake Ontario, and 12.8
for Seneca Lake.
Fall spawning survey Yankee Reef: A total of 109 fish were captured,
providing 26adipose clipped fish and 18 CWT. Mean age of all lake trout
captured at Yankee Reef in 2001 was 7.0 compared to 6.3 in 2000.
Analysis of coded-wire tag returns (1987-2001) from fish stocked at Six
Fathom Bank has continued to show superior survival of the Seneca Lake
strain compared with the other strains. In terms of being able to survive
beyond the age of first maturity, the Seneca Lake strain is by far the
most abundant strain encountered in the age 8 and older age-classes.
In total, 214 lake trout were caught in the Northern Refuge in May of
2001. Of the 214 caught, 138 coded-wire tags were recovered. Strain
composition of the lake trout containing coded-wire tags was 1.4% Lake
Ontario, 73.9% Marquette-Superior, 23.9% Seneca Lake, and 0.7% Lewis Lake.
By age, regardless of strain, 0.7% were age 2, 29.0% were age 3, 46.4%
were age 4, 13.0% were age 5, 7.2% were age 6, 1.4% were age 7, 0.7% were
age 9, 0.7% were age 11, and 0.7% were age 12I.
Invasive Species Program
The ruffe and
round goby are two invasive fish species that have expanded their range
within the upper Great Lakes. Both are native to Eastern Europe and
probably transported to the Great Lakes in the ballast water of
ocean-going vessels. They have a competitive advantage over native fish
for food and habitat because they are frequent spawners, allowing them to
become abundant quickly, and they have aggressive natures. Although the
known range of ruffe continues to be confined to one location (Thunder
Bay), the range of round goby has spread to many areas in the lake,
including: Caseville, Essexville, Flint River, Harbor Beach, Lexington,
National Gypsum, Nayanquing Pt., Port Sanilac, Presque Isle, Pt. Lookout,
Rogers City, Shiawassee River, and Tawas City.
Ruffe have not been detected in any areas outside of the Thunder Bay area
to date.
Interim measures imposed by the Lake Carriers Association in the Thunder
Bay area may be one of the reasons that ruffe have not spread out of
Alpena to other areas of Lake Huron or the Great Lakes; however, goby may
be spread from port to port in other areas where these measures were not
in place.
In an
effort to prevent the spread of invasive species into the Mississippi
River, Alpena FRO has supported and actively assisted in surveillance and
control trawling and trapping for round goby and other exotics in the
Chicago Shipping and Sanitary Canal and the Illinois Waterway annually
since 1994. The FWS LaCrosse, WI FRO, coordinates these efforts to
document the spread of round goby in these tributaries to the Mississippi.
Many federal, state and community agencies cooperate in this effort.
Stocking Policy
The
constant stocking policy has failed to produce natural reproduction, with
evidence of diminishing returns, and evidence that suppress wild portion.
A total of 981,216 lake trout are programmed for Michigan waters of Lake
Huron in 2002.
Lake Superior
Wisconsin DNR
Lake Trout Assessment
Spawning
assessments were conducted on three reefs in October to monitor trends in
abundance. The population at Gull island Shoal declined in the 1950s and
by 1961, no females were sampled during annual assessments. Since
implementation of planned stocking programs, spawner abundance has
continually increased due to sea lamprey control, sport and commercial
harvest restrictions and the creation in 1976 of the Gull Island Refuge.
The Gull Island Shoal stock population still has the capacity to increase.
Abundance at San Cut Reef has remained stable.
Sport Harvest
An annual
creek survey was conducted at all major ports along the Wisconsin
shoreline. In 2001, 40,427 angler trips, resulting in 200,555 angling
hours were spent on Lake Superior. The harvest was estimated at 30,223
salmonids. Twenty-three charter fishing operations were active in 200,
reflecting decline in participation since a peak of 50 licenses in 1990.
2001 WI Salmonid Stocking
Lake Trout
180,980
Splake 106,738
Brown Trout
127,970
Chinook 520,958
2002 WI Proposed Salmonid
Stocking
Lake Trout 89,400
Splake 120,000
Brown Trout 85,000
Chinook 300,000
Minnesota DNR
Lake Trout assessment
Catch per unit
effort (CPUE) of stocked lake trout decreased from 2000 to 2001. The total
CPUE of stocked lake trout in the May assessment generally increased from
1976-1982, then stabilized at about 50 lake trout/1,000m of net through
1991, and has since generally declined to a low of 13.4 lake trout/1,000 m
in 2001. The average total CPUE of stocked lake trout during the 1992-2001
period was well below the 1976-1991 average. The decrease in CPUE in the
larger size groups may partially reflect the low numbers of lake trout
stocked in 1987 and 1988 following the EED outbreak in the federal
hatcheries. There has also been a lakewide decline in survival of stocked
lake trout.
The total CPUE of wild lake trout increased sharply in 2001 to 46.2 lake
trout/1,000m, the highest reported since the assessment began. The
greatest relative increases in 2001 occurred in the 21-24 in. and the 29+
in. size groups.
In general, wild juvenile lake trout have continued to increase steadily
since 76 and in 1999 recorded a large increase reaching an all-time high
CPUE of 92.6 lake trout/1000 m. In 2000 and 2001 CPUE of wild juvenile
lake trout declined, but was still at one of the highest levels recorded.
Percent of wild lake trout increased from 53% in 1999 to 59% in 2000 and
to 67% in 2001, the highest ever reported. The increase indicates a
sustained upward trend.
Commercial/Forage Species
Lake herring
Lake herring
abundance has increased substantially in the commercial catch since 1985.
In 2001, total harvest of lake herring in the gill net fishery was 319,412
lb. and CPUE was 224.7/1,000 ft. Both harvest and CPUE decreased when
compared to the 2000 total harvest of 450,100 lb. and CPUE of 308.8
lb/1,000 ft. The adult lake herring stock appears to be decreasing in
Minnesota waters, as indicated by the commercial catch statistics from
1995-2001. However, a very strong 1998 year class which was well
represented in the USGS 99 spring forage survey may be starting to
recruit to the fishery as indicated by the occurrence of younger, smaller
fish in the 2001 harvest. The 1998 year class was the strongest recorded
in Minnesota waters since 1990.
Rainbow smelt
The spring
rainbow smelt spawning run along the Minnesota shore of Lake Superior
remained at a very low level, and few fish were captured in the dip net
fishery, compared to the pre-1980 period. From 1980-1990, commercial
harvest had stabilized at approximately 15% of the average harvest during
the 70s. Commercial harvest in the 2000 pound net fishery was 44,282 lb.
and increased to 85,645 lb. in 2001. CPUE increased sharply from 1,107
lb./lift in 2000 to 2,763 lb./lift in 1002. In 2001 there were only two
smelt fishermen in the pound net fishery, both located in MN-1. No
commercial trawling for smelt occurred in 2001.
Trout & Salmon
In 2002,
Minnesota plans to produce and stock three species of trout and salmon.
Two strains of rainbow trout will be produced: steelhead and Kamloops. All
steelhead will originate from MN stocks. The Chinook salmon program was
revised in 1998, with the new quota set at 355,000 fingerlings. MN plans
to secure eggs from Lake Huron through 2002, and stock approximately
356,000 lake trout. Starting in 2003, lake trout will no longer be
stocked.
2001 MN Salmonid Stocking
Lake Trout
358,032
Chinook 367,628
Kamloops 93,955
Steelhead
445,000
Proposed 2002 MN Salmonid
Stocking
Lake Trout
356,400
Chinook 355,000
Kamloops 92,500
Steelhead
540,000
Sea Lamprey management
Tributary Information
·
Lake Superior
has 1,566 (733 U.S., 833 Canada) tributaries.
·
136 (89 U.S.,
47 Canada) tributaries have historical records of sea lamprey larvae
production.
·
70 (41
U.S., 29 Canada) tributaries have been treated with lampricide at least
once during 1992-2001.
· Of
these, 58 (30 U.S., 28 Canada) tributaries are treated on a regular 3-5
year cycle.
Lampricide Control
· Treatments
were successfully completed in all 20 scheduled tributaries (16 U.S., 4
Canada).
·
A treatment
effectiveness study was conducted in the Big Carp River, Ontario.
·
A protocol
for application of lampricides to streams with populations of
young-of-year lake sturgeon was followed in treatments of the Ontonagon,
Bad, and Sturgeon rivers. Lampricide concentrations were restricted to 1.0
times minimum lethal concentration (MLC; concentration required to kill
99.9% of sea lampreys) in the lower reaches of the Ontonagon and Bad
rivers and 1.2 times MLC in the Sturgeon River.
·
A written
agreement was reached with the Bad River Band that allowed access to
Tribal lands for treatment of the Bad River. Treatment was completed
successfully.
·
The Potato
and Cranberry rivers, treated during 2000, were retreated during 2001.
Treatments were complicated by low discharge, beaver dams, and
intermittent rain.
·
Mortality of
non-target organisms was not significant in any of the tributaries
treated.
Alternative Control
programs
Sterile Male Release
Technique
·
A total of
1,507 spawning-phase male sea lampreys were transported to the
sterilization facility from the month-long trapping operations on the
Rock (365), Misery (202), Brule (621), and Middle (319) rivers.
Barriers
·
A preliminary
screening of 400 dams identified 4 barriers as being important to sea
lamprey management in Lake Superior. This inventory will be an essential
tool in identifying additional dams with value to lamprey control.
·
Black
Sturgeon River: OMNR is assessing alternatives for passing non-jumping
fish at their dam on the Black Sturgeon River with the specific goal of
improving walleye stocks in Black Bay. The cost of treating the entire
Black Sturgeon River has been estimated at $306,000 (U.S.) if lampreys
were allowed upstream of the current dam.
·
Betsy River:
Shelldrake Dam was repaired. The dam was previously proposed for removal,
but was retained based in part on its value as a lamprey barrier.
·
Iron River:
Orienta Dam was removed and replaced with a lamprey/fish barrier. Removal
of the dam was funded by the owner, Xcel Energy.
·
Little Carp
River: A feasibility study and fisheries assessment were completed for
construction of a barrier.
·
Bad River:
The Army Corps of Engineers completed a water restoration plan for a
proposed barrier.
· Misery
River: An automatic water level recording station was installed at the
barrier to help evaluate the performance of the barrier after the widening
of a narrow bridge just downstream of the barrier.
Assessment
Larval
·
Lamprey
larvae population assessments were conducted in 106 tributaries (48 U.S.,
58 Canada) and offshore of 3 U.S. tributaries.
·
Pre- and
post-treatment assessments were conducted in 11 tributaries (7 U.S., 4
Canada) to determine the effectiveness of lampricide treatments.
Spawning-phase
·
9,188 sea
lampreys were trapped in 21 tributaries.
·
Estimated
spawning-phase sea lamprey populations was 82,229 (33,737 western U.S. and
48,492 eastern U.S. and Canada).
· Spawning
runs were monitored in the Amnicon, Middle, Bad, Firesteel, Misery, and
Silver rivers, Red Cliff Creek, the Brule River, and the Miners River.
Parasitic-phase
·
31 sea
lampreys attached to lake trout were collected from 3 management
districts.
·
Lampreys were
attached at a rate of 0.65/100 lake trout.
·
A total of
9,020 (7,508 U.S.; 1,512 Canada) spawning-phase sea lampreys were scanned
for coded wire tags in 18 (11 U.S.; 7 Canada) Lake Superior streams.
· A
total of 1,046 metamorphosing sea lampreys were marked with coded wire
tags and released into Lake Superior tributaries. Recapture of these
lampreys as spawning-phase adults will take place in 2003.
Status of Fishes lakewide
Prey Species
Historically
lake herring was the dominant prey fish in Lake Superior. They supported
lake trout populations and composed most of the commercial fishery
landings. Populations of herring declined drastically in U.S. waters
during the mid 60s. The collapse has been attributed to overfishing, and
to predation by and competition with rainbow smelt.
Smelt became abundant during the 30s, 40s, and 50s and were the main
component of the near-shore prey community until the early 1980s when a
significant decline was observed in U.S. waters. Smelt densities have
remained low for the past 17 years and are not expected to recover to
former levels. Though recruitment of smelt has remained stable, predation
limits the number of fish living beyond age 4. Recent surveys in Ontario
waters indicate that densities there are much higher and mortality lower
than in U.S. waters. Even though smelt densities are depressed, this fish
still composes a large portion of the diets of near-shore predators.
Lake herring began to recover in 1978 and densities increased further in
the 80s because of large year classes produced in 84, 88, 89, 90 and
98. Moderate to large parental stock sizes have been present since the
late 80s, but their progeny were few. Despite the abundance of parental
stocks, recruitment from 91 to 98 has been poor, resulting in an 80%
reduction in biomass since a peak in 1990. Adult herrings are now too
large to be consumed by any but the largest predators. The low biomass of
both smelt and herring has resulted in a shift of predation to sculpins,
ninespine sticklebacks, terrestrial insects, and other previously
underutilized food resources, emphasizing the important of these species
as a reserve forage base.
Lake Trout
Lake trout
were, and continue to be, the dominant predator in Lake Superior. At least
three forms of lake trout have been recognized in the lake; leans,
siscowets, and humpers, although up to 12 morphological variants have been
reported. Lean lake trout are the most commonly recognized form, and along
with siscowets, are the dominant predators in near-shore waters less than
260 ft. deep and over shallow offshore reefs. Siscowets inhabit mainly the
offshore waters deeper than 260 ft., but they are also common in all
near-shore waters. Humpers are the least abundant of the three forms of
lake trout and live primarily on deep, offshore underwater reefs around
Isle Royale and in the eastern waters of the lake around Caribou
Island.
All three forms of lake trout were represented in the historic commercial
harvest that annually averaged over 800,000 lbs. during 1929-1943, the
time period just before the collapse of lean lake trout populations began.
Lean lake trout composed 87% of the historic harvest from Wisconsin waters
and 75% in Michigan waters. Siscowets are currently the most abundant form
of lake trout in Lake Superior, and surveys in 96 and 97 indicate that
they are expanding their distribution into near-shore waters and
outnumbering lean lake trout in some areas.
Nearly the entire lake is important habitat for all three forms of lake
trout. In offshore areas, important spawning habitat is found on Gull
Islands, Superior Shoal, Stannard Rock, Caribou Island, Michipicoten
Island, and in eastern Ontario waters.
Lake Whitefish
Lake whitefish
populations in were reduced in the early part of the 20th
century, possibly as a consequence of progressive elimination of discrete
stocks. In the past two decades, populations have greatly increased, as
reflected by the commercial catch per unit of effort, where commercial
harvests have been in excess of 1,000 tons annually since 1990.
Lake whitefish spawn in early November over coarse sand or rubble in
shallow water. Spawning habitat occurs throughout the lake over this type
of substrate in embayments and the near-shore habitat zones. Reports also
indicated the existence of river-spawning populations, such as those in
the St. Marys River rapids above the control gates, the St. Louis River
in the U.S., and the Michipicoten, Dog and Kaministikwia rivers in
Ontario.
Walleye
Historically,
the largest populations of walleye were found in Black Bay (Ontario) and
the St. Louis River (Minnesota and Wisconsin) and its embayment. Walleye
in the St. Louis River are already considered rehabilitated. Walleye are
currently found in about 79 tributaries and in most bays on Lake Superior.
Impediments to achieving the walleye goal include fishing-induced
mortality and habitat degradation, including poor water quality. Habitats
of walleye have been degraded by logging and agricultural practices, river
bank erosion, wetlands development, hydropower development, and
sedimentation.
Lake Sturgeon
Currently,
nine tributaries to Lake Superior are known to support self-sustaining
populations of lake sturgeon: Sturgeon, Bad, Big Pic, Black Sturgeon,
Goulais, Gravel, Kaministiquia, Michipicoten, and Nipigon rivers.
Populations in all nine tributaries are reduced from historical levels of
abundance, but they appear to be recovering.
Brook Trout
A large
anadromous or lake dwelling form of brook trout, called coasters, was
historically widespread and common in the very near-shore waters of Lake
Superior. Brook trout provided a highly valued and productive fishery
along shoreline areas of the lake, and in tributaries with spawning
populations. They were known to inhabit at least 118 streams tributary to
Lake Superior. Populations were extirpated rapidly during the 1880s.
Restoration and protection of tributary habitat is essential for achieving
the brook trout goal because habitat is currently an impediment to
achieving the goal for brook trout. Hydroelectric development and
operation, barrier dams, land-use practices, timber harvesting, and
sedimentation all contribute to the loss of habitat for brook trout.
Additional impediments to brook trout in Lake Superior may be Splake
and/or naturalized salmonines that occupy tributary habitat during their
life cycle.
Pacific Salmon, Rainbow
Trout, and Brown Trout
Non-indigenous
top predators currently include rainbow trout, brown trout, Chinook
salmon, Coho salmon, Splake, pink salmon, and Atlantic salmon. Splake is
stocked in some areas of the lake to provide a sport fishery. The annual
yield of these species accounts for 15-20% of the total harvest of all
salmon, trout, and chars from Lake Superior. All of these species are
sustained by natural reproduction and stocking, except Splake which is not
thought to reproduce in the wild.
Stocking of Coho salmon has been discontinued throughout the lake, yet
Coho continue to be an important sport fish and spawn in at least 79 lake
tributaries. Returns of Chinook salmon to sport fisheries in the areas
where they were stocked have declined. Naturally reproduced Chinook salmon
make up over 75% of the sport harvest of this fish from Lake Superior.
Pink salmon were accidentally stocked in Lake Superior, but became
established and have colonized spawning streams around the whole lake.
Rainbow trout, naturalized in over 200 of 1,525 Lake Superior tributaries,
are probably the most successful Pacific salmon.
Non-indigenous salmon and trout depend upon tributaries to Lake Superior
for reproduction and rearing of juveniles, and have developed
self-sustaining populations throughout the lake.
The
effect of competition and/or predation by stocked and wild salmon and
trout on lake trout and brook trout remains a concern for management
agencies, but that concern does not apply to the offshore waters of the
lake. If salmon and trout are depressing lake trout or brook trout
populations, these effects would occur in the near-shore zone where
introduced salmon and trout are most abundant. Non-indigenous salmon and
trout, however, may compete with lake trout or brook trout in tributaries.
Fish Community Objectives
The Lake
Superior fishery management agencies initiated an effort to update their
vision for the Lake Superior fish community. The new document replaces the
original Fish community Objectives for Lake Superior.
Changes in the Lake Superior fish community converge around three themes.
First, the fish community is reverting to a more natural state, resembling
historical conditions, requiring less management intervention and control.
Second, success in rehabilitating lake trout and the recovery of many lake
herring populations have allowed management attention to shift toward
depleted species in embayment and tributary habitats. Third, the fish
community has been permanently altered by non-indigenous nuisance species,
and remains at risk from further introductions.
The document is intended to provide a framework for decision-making. It
states it is not a management tool.
Recent efforts to coordinate with environmental organizations have been
fruitful, further encouraging fishery and environmental interests to work
toward a healthy and productive Lake Superior. Comprehensive reports on
progress toward achieving the objectives (state-of-the-lake) will be given
at 5-year intervals.
Goal
To rehabilitate and
maintain a diverse, healthy, and self-regulating fish community dominated
by indigenous species and supporting sustainable fisheries.
Some highlights include:
·
Fish habitats
must be protected
·
Lake
productivity is limited
·
Naturalized
species are part of the ecosystem
· Further
introductions of non-indigenous species must be prevented
·
Fish and
fisheries are culturally important
·
Unexploited
fishes are also important
·
All citizens
have a stake in Lake Superior fisheries
·
Management
decisions should be supported by science
·
Ability to
manage these fish communities is limited
·
Preservation of indigenous species is of the highest concern
·
Genetic
diversity and fitness must be maintained
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