June 11, 2001

 Sea lampreys in Lake Ontario

   Lake Ontario has 659 (254 US, 405 Canada) tributaries: 57 (27 US, 30 Canada) tributaries have historical records or production of sea lamprey larvae. 39 (20 US, 19 Canada) tributaries have been treated with lampricide at least once during 1990-2000.  Of these, 31 (16 US, 15 Canada) tributaries are treated on a regular 3-5 year cycle.
   Lampricide treatments are systematically scheduled for tributaries harboring larval sea lampreys to eliminate or reduce the populations of larvae before they recruit parasitic juveniles to the lake. Treatment units administer and monitor doses of the lampricide TFM, sometimes augmented with Bayluscide.
   Treatments were completed successfully in 9 scheduled tributaries (3 US, 6 Canada). Mortality of non-target fish was minimal in the majority of treatments. About 300 common white suckers and 500 northern log perch were killed in the lower portion of Farewell Creek. Tributaries treated in 2000 included:

The Catfish, Sterling, and Little Salmon rivers. And in Canada, Port Britain, Farewell, Oshawa, Wilmot, Mayhew, and Salmon rivers. The Commission is committed to reducing the use of TFM through the implementation of alternative lamprey control strategies that include the use of barriers to sea lamprey migration  including the Sterile Male Release Program
   Presently, 12 barriers have been constructed or modified to block sea lampreys in Lake Ontario. Larval sea lampreys were discovered for the first time in No Name Creed, Ontario. Larval sea lampreys were captured in Scriba Creek (Oneida Lake, New York) for the first time since 1984. 5,033 sea lampreys were trapped at 14 sites in 13 tributaries. The frequency of fresh lamprey wounds in lake trout has been demonstrated to be a direct indicator of mortality due to lamprey. The lamprey wounding levels remain well below the rates observed during the 1970s and early 1980s.

Chinook Salmon: In 2000, OMNR stocked about 2.2 million salmon and trout into Lake Ontario. About 444,000 lake trout yearlings were stocked as part of a long-term rehabilitation program. Efforts are focused in eastern Lake Ontario where most of the historic spawning shoals are found. About 150,000 rainbow trout yearlings were stocked and 239,000 fry were raised by local community groups. About 167,000 brown trout yearlings were stocked at various locations.
   The length of male/female chinook salmon during 2000 remained high, as good as the past several years. Such good growth rates were consistent with the availability of the strong 1998 and 1999 year classes of alewife for food.

Rainbow trout: Catch rates of rainbow trout in Ontario waters of Lake Ontario were positively correlated with spring air temperatures. The poor catch rates of rainbow trout in 2000 were consistent with one of the colder springs in recent years. During

years with warm springs such as 1998, the catch of rainbow trout was higher during spring. These high catch rates were consistent in timing and location with the migration of wild post-spawning rainbow trout from north shore streams.
Lake trout: The decline in numbers of adult lake trout continues. The decline started in the mid-1990s, and is partly attributed to a reduction in stocking in 1993 to half the previous levels. Lake trout tend to remain near their stocking location, and therefore reduced stocking cannot account for the magnitude of the decline in adult fish.
   The decline is largely due to low survival of the stocked fish during their first year in the lake. A decrease in early survival has been observed since the 1980s, but in the early to mid-1990s, it dropped precipitously. Reduced survival of young fish effectively means reduced recruitment, and a shift in the age structure toward older fish.

   Lake Ontario supports a small but locally significant commercial fish industry. The commercial harvest comes primarily from the Canadian waters of eastern Lake Ontario and the Bay of Quinte. The most important species in the harvest include yellow perch, lake whitefish, walleye, eel and brown bullhead.
   Lake whitefish harvest was 293,133 lbs., 50% of the quota, in 2000. The annual lake whitefish harvest has declined since 1996. Eel harvest was 28,812 lbs., 8% of the quota. Eel harvest had been in decline since 1992 but doubled between 1999 and 2000. Yellow perch harvest was 255,743 lbs. 56% of the quota. Yellow perch harvest had increased significantly from 1996 to 1999 but declines slightly in 2000. Walleye harvest was 12,302 lbs., 17% of the 

quota. Walleye harvest has declined significantly in the past two years.  The St. Lawrence River supports a commercial fishery with an annual harvest of about 350,000 lbs. with a landed value of about $400,000. The most important species in the harvest include yellow perch, sunfish, brown bullhead, and eel.

   Commercial fishing activity in the New York waters of Lake Ontario is limited to the nearshore open waters of the eastern end of the lake. Commercial fishing gear includes gill nets, trap nets, and fyke nets. Commercial harvest is targeted at: yellow perch, brown bullhead, sunfish, white perch, rock bass, and black crappie. In 1997, '98, '99, and 2000 the number of licensed, active commercial fishermen was 12, 11, 7, and 7, respectively. The decline in the number of commercials is directly attributable to revocation of licenses held by five individuals involved in the illegal harvest and sale of American eel and walleye.

Boat Fishery in W. Lake Ontario - OMNR

   The boat fishery for salmon and trout in western Lake Ontario represents about one-third of the salmon and trout fishery; stream and shoreline fisheries account for the remaining two-thirds. The effort of launch daily anglers and all boat anglers was estimated at 300,549 and 484,727 angler-hours, respectively. Effort in the western Lake Ontario boat fishery has been relatively stable since 1994.
   A regulation change allowing two rods per angler in Lake Ontario came into effort during summer 1998. This resulted in effort in rod-hours exceeding angler-hours by 27% in 1999 and 29% in 2000.
   Chinook salmon and rainbow trout accounted for 

about 90% of the salmonid harvest. These were the

only species that were consistently targeted in this fishery. The catch and harvest of Chinook salmon in 2000 were similar to 1999. Catch and harvest rates of Chinook salmon have been variable over the last 16 years with no recent trend apparent.
   The catch and harvest of rainbow trout declined in 2000. Catch and harvest rates of rainbow trout were significantly lower than average for the previous 15 years. Rainbow trout catch rates tend to be lower during years with cooler springs. During 2000 the low rainbow trout catches in Ontario waters were consistent with a cool spring.
   Catch and harvest of coho salmon, brown trout and lake trout remained typically low, because anglers target Chinook salmon and rainbow trout.

 Fishing Boat Census - NY

   NYSDEC has sampled the recreational boat fishery for 16 years, usually between period April 1 to September 30. The census for 2000 was estimated at 97,068 boat trips, an estimate very similar to the previous four years. Compared to 1999, effort was down 1,178 boat trips or 1.2%. Compared to the peak observed in 1990, effort in 2000 was down 120,755 fishing boat trips or 55.4%. Boat angler trips in 2000 were estimated at 268,672 with an average of 2.77 anglers per boat. Boat angler hours last year were estimated at 1,367,870 with an average length of 5.09 hours per boat trip.  The sampling documents all recreational boats.
   Fishing effort targeted at trout and salmon was estimated at 64,979 boat trips, a 4.7% increase compared to 1999. Trout and salmon anglers still accounted for 67% of fishing boat trips in 2000.
   Smallmouth bass fishing effort has shown a slow statistically significant increase averaging 737 fishing boat trips per year. Effort targeted at smallmouth bass last year was 27,857 fishing boat trips, the second highest estimate among the years censused. The average percent contribution of the smallmouth bass fishery has increased as the number of trout and salmon anglers has decreased, and in 2000 smallmouth bass anglers accounted for 28.7% of fishing boat trips. Walleye and yellow perch were the third and fourth most common species specifically targeted by open lake boat anglers, but comprised only 0.81%, and 0.62%, respectively, of the estimated fishing boat trips.
   Nonresident anglers continue to be a very important component of the boat fishery, comprised 40% of the boat anglers interviewed. Pennsylvania remained the principal source of nonresident anglers, contributing 18.6% of the total anglers. Other major sources of nonresident anglers in 2000 were: New Jersey (4.7%), Ohio (3.9%), Massachusetts (3.7%), Connecticut (2.4%), and Vermont (2.3%).
   Charter effort was estimated a t 12,605 fishing boat trips, up 16.9% compared to 1999 but down 40.2% compared to the 1988 peak.
   Charter trips have always differed significantly from noncharter trips: have a higher proportion of nonresident anglers, have higher catch rates, and harvests a higher percentage of the catch. The average charter harvested 3.583 salmonids per boat trip versus 0.637 for noncharters. Charter boats fishing for trout and salmon accounted for 56.4% of all salmonids harvested within the census area.

Coho Salmon:
Coho salmon moved from its traditional position as the fifth most commonly harvested salmonid species to fourth place, due largely to a decrease in lake trout harvest. 7,466 coho salmon were harvested in 2000, an 11.3% decline compared to 1999 (second highest seasonal harvest rate), but only 1.5% less than the 1995-99 average harvest rate.

Chinook Salmon:
Chinook salmon was the second most commonly harvested salmonid species with an estimated harvest of 25,478 fish, 32.8% of the total number of trout and salmon taken. The 2000 harvest was the lowest Chinook salmon harvest among the 16 years surveyed, a 14.5% decrease compared to 1999 and a 15.2% decrease compared to the 1995-99 average.  Chinook salmon populations in Lake Ontario are heavily dependent on annual stocking programs, and Chinook salmon stocking targets were substantially reduced in 1993 and again in 1994. Stocking target was increased in 1997 to an intermediate level of 1.6 million fingerlings.

Rainbow Trout:
Rainbow trout harvest decreased dramatically in 2000 to 9,816 fish, the lowest harvest estimate among the 16 years censused. Harvest in 2000 was down 51.8% compared to 1999 and down 60.4% compared to the 1995-99 average. Rainbow trout remained the third most commonly harvested species of trout or salmon in 2000, but contributed only 12.7% of the total salmonid harvest.

Atlantic Salmon:
New York’s Lake Ontario Atlantic salmon program was changed in 1990 from a small scale experimental project with an annual stocking target of 50,000 yearlings, to a larger put-grow-take program for trophy fish with an annual stocking target of 100,000 yearlings and fall fingerlings.

   Significant increases in number harvested or number caught did not occur, and aside from a spike in harvest and catch in 1994, there has been an overall pattern of decline among the year censused. In 2000, only one Atlantic salmon was observed among all the boats interviewed, resulting in a harvest estimate of just 24 fish. Total Atlantic salmon catch was estimated at only 428 fish.

Brown Trout:
Brown trout harvest increased in 2000 to 27,483 fish, up 24.5% compared to 1999 and up 10.1% compared to the 1995-99 average harvest. Brown trout were the most commonly harvested trout and salmon species within the area censured in 2000, accounting for 35.4% of the total salmonid harvest.

Lake Trout:
Lake trout harvest declined dramatically in 2000, with an estimate of just 7,319 fish. This was the lowest lake trout harvest among the 16 years censused, and a 46.6% decrease compared to the 1995-99 average harvest. Lake trout was the fifth most commonly harvested salmonid species in the 2000 census, contributing just 9.4% of the total trout and salmon harvest.

Total Salmonids:
Total harvest of all species of trout and salmon in the 2000 fishing boat census was estimated at just 77,586 fish. This was lowest harvest total among the years censused, a 16.5% decrease compared to 1999 and a 23.7% decrease compared to the 1995-99 average harvest.
   Among charter boats fishing for trout and salmon, the 2000 seasonal harvest rate was 3.583 salmonids per boat trip, down 23.1% compared to 1999 and down 21.9% compared to the 1995-99 average. Noncharter boats fishing for trout and salmon, the seasonal harvest rate was 0.637 salmonids per boat trip, down 25.0% compared to 1999 and down 19.5% compared to the 1995-99 average.

Smallmouth Bass:
Smallmouth bass has been the most commonly harvested fish species in the fishing boat census since 1995, due in part to decreases in trout and salmon harvested. Total harvest in 2000 was estimated at 74,954. Although this was a 19.0% decrease compared to 1999, it was still the third highest harvest estimate among the years censused, and 45.3% higher than the '95-'99 average harvest. Harvest rate among boats was 2.539 bass per boat trip.
        Only one of the geographic sites shows a persistent, statistically significant pattern or trend. This occurred at the Henderson site which showed a decline in harvest rates relative to lake-wide rates occurring between 1990 and 1991. From 1985-90, harvest rates per angler hour at the Henderson site were nearly equal to or greater than the lake-wide rates and averaged 1.155. From 1991-2000, harvest rates at Henderson were all below the lake-wide rates with a 10-year average ratio of 0.722. Reasons for the decline in the Henderson site harvest rates correspond with the period when mortality of young smallmouth bass increased significantly in the eastern basin presumably in response to cormorant predation.

Yellow Perch and Walleye:
Yellow perch harvest was estimated at 10,127 fish. This was a 26.9% decrease compared to 1999, but a 57.6% increase compared to the 1995-99 average harvest. Yellow perch catch was estimated at 25,467 fish in 2000, the fourth highest catch estimated among the years censused, and a 17.3% increase compared to the 1995-99 average catch. Walleye continued to be a relatively minor component of the open lake boat fishery, although angler interest in this species remains high.
   Walleye harvest within the area censused declined to 496 fish, a 61.5% decline compared to the 1995-99 average harvest. Many of the walleyes taken are considered to be of trophy size, and the average length for the walleyes sampled in the 2000 census was 25.9 inches.

Stocking Summary:
The stocking summary for the  New York waters of Lake Ontario is: Atlantic. Salmon, 187,594; Brown Trout, 421,300, Chinook, 1,654,300; Coho, 254,040; Lake Trout, 489,616; Rainbow Trout, 608,425; Walleye, 129,259; Grand Total = 3,744,534.

   In September 2000, the NYSDEC and USGS completed the annual cooperative gill net survey of adult lake trout. Twelve sites were fished. A total of 42 graded mesh nets were lifted presenting a 20% decrease in effort from other years. A total of 489,500 yearling lake trout were stocked in U.S. waters of Lake Ontario during 2000.  The strain composition was 38% Seneca Lake wild, 37% Lake Superior domestic, and 25% Lewis Lake wild. All fish stocked near Stony Island, Oswego, Oak Orchard, Olcott and Sodus Bay.

   A total of 15 naturally produced lake trout were caught with bottom trawls. They ranged in size from 

1.6 to 10.6". Survival of naturally produced lake trout

to the fingerling stage occurred each year during 1993-2000. The modest level of reproductive success, 8 successive year-classes produced with fish from the first 7 year-classes surviving to age-1, is an important early sign of successful natural reproduction and meets the plan objective to demonstrate the feasibility of lake trout rehabilitation in Lake Ontario. The distribution of catches of wild fish suggests that lake trout are reproducing throughout New York waters. Although these signs are very encouraging, achieving the goal of a self-sustaining population will require continued improvement in production of wild lake trout.

Cormorant Management in Lake Ontario’s Eastern Basin

  Double-crested cormorants on the Great Lakes have undergone a tremendous population increase in the past 30 years (Hatch 1995). First reported on Lake Superior in 1913, cormorants expanded eastward throughout the Great Lakes and began nesting on Lake Ontario in 1938 (Baille 1947). Populations increased steadily during the '30s and '40s, and by the early '50s  the cormorant was so common that control measures were authorized in some parts of Ontario, Canada to reduce suspected competition with recreational interest. The first reported breeding in New York State occurred in 1945 at Gull Island, Lake Ontario.
   In New York, breeding numbers and locations have increased dramatically over the past two decades. There are currently five areas in interior New York where cormorants nest and four areas where control measures are being used. Little Galloo Island was first colonized by cormorants in 1974. It currently supports the largest double-crested cormorant colony and the only Caspian Tern colony in the State. Other areas of New York include: Lake Champlain in 1982, Oneida Lake in 1984, and the Niagara Frontier in 1997.
   Cormorant numbers on Little Galloo Island have increased from 22 nests in 1974 to a peak count of 8,410 nests in 1996. In 1998, NYDEC and USGS research identified a connection between cormorant numbers and excessive mortality of young smallmouth bass, which accelerated the implementation of a five-year management plan for U.S. waters of the eastern basin of Lake Ontario by NYSDEC.

   Cormorant management activity in the eastern basin of Lake Ontario has focused Bass, Calf, Gull and Little Galloo Islands. All four islands are located in Jefferson County, NY. Gull and Little Galloo Islands are owned by NYSDEC, Bass and Calf Islands are privately owned. The islands contain several colonial waterbird colonies. Management and monitoring activities for all four islands were carried out by Region 6 NYSDEC staff. A USFWS depredation permit was obtained to oil eggs on Little Galloo Island and remove nests on Bass, Calf and Gull Islands. Nest removal activities on Gull and Bass Islands began in 1994. In 1997, Calf Island was included.

   NYSDEC staff began treating all accessible cormorant nests on Little Galloo island with pure food grade vegetable oil beginning 16 May 2000. This was the second year of treatment. The oiling process was conducted four times at two week intervals. Oil use for all visits totaled 55 gallons, down from 78 gallons in 1999. Each nest or group of nests treated was marked with spray paint to ensure treatment of all nests accessible from the ground.

   In addition to nest removal and oiling activities, NYSDEC collected regurgitated pellet samples for diet analysis at Little Galloo Island beginning April 25, and made collections every two weeks through September 26. Regurgitated pellets have been collected at Little Galloo island since 1992. In 2000 NYSDEC collected samples at Snake and Pigeon Islands in Canadian waters, under permit from the OMNR. Samples were collected from these islands monthly from April 30 through September. All samples were analyzed by the USGS.
   On Little Galloo Island, cormorant reproduction was controlled to maintain nesting opportunities for other colonial waterbird species and protect the declining smallmouth bass fishery. Gull, Calf, and Bass Islands were managed to prevent the establishment of new cormorant colonies and to protect a black-crowned nigh heron colony on Gull Island.
   Since the nest removal program began in 1994, there has been no successful double-crested cormorant reproduction on Gull, Bass and Calf Islands.
   The number of eggs oiled on Little Galloo island in 2000 ranged from 5,509-10,917 per trip. Hatching success for oiled nests was less than 1%. This met the objective set in the NYSDEC five year management plan to reduce the number of successful cormorant nests on Little Galloo island by 90%. Less than 300 cormorant chicks hatched on Little Galloo island in 2000, mostly in untreated tree nests.
   Management has moved towards meeting objectives for protecting waterbird and fish communities by maintaining nesting populations of black-crowned night heron on Bass and Gull islands and by substantially reducing consumption of smallmouth bass on Little Galloo Island. Site specific management is a moderately labor intensive undertaking, although not particularly expensive in comparison to other mortality control projects, such as sea lamprey management.

   Until 1999, when it was surpassed by the High Bluff Island colony in the central basin of Lake Ontario, Little Galloo Island in the eastern basin supported the largest cormorant colony. Fish consumption by the Little Galloo Island cormorant colony has averaged 35.0 million fish (3.02 million pounds) since 1992, attaining a peak level of 65.3 million fish consumed in 1997.
   Alewife (58.7%) and yellow perch (38.4%) were the major fish consumed during the chick feeding and post-chick feeding periods, respectively. yellow perch. Yellow perch (17.7% to 38.4%), cyprinids (4.2% to 14.9%), smallmouth bass (6.1% to 10.3%), pumpkinseed (1.7% to 4.3%), and trout perch (0.3% to 6.4%) contributed more to the diet during the post-check feeding period.

   Three-spine stickleback (45.5%) were the major fish species consumed by cormorants from the Pigeon Island colony. Yellow perch (15.8%) and alewife (13.5%) were the second and third ranked prey. Smallmouth bass (2.2%) was the major gamefish consumed by Pigeon Island cormorants.
   Yellow perch (43.3%) dominated the diet of cormorants from Snake Island. Smallmouth bass (1.0%) was the principal gamefish consumed by Snake Island cormorants.

   For the entire feeding season, cormorants from the 

Pigeon and Snake island colonies consumed 30,000

and 7,000 lbs of smallmouth bass, 67,000 and 76,000 lbs of yellow perch, 90,000 and 31,000 lbs of rock bass, and 9,000 and 31,000 lbs of pumpkinseed, respectively.
   Fish consumption by cormorants from Snake Island was higher than in 1999 (9.0 million fish compared to 6.7 million fish in 1999), but lower at Pigeon Island (11.5 million fish versus 15.3 million fish in 1999).  Cormorants from Little Galloo island consumed 20.2 million fish in 2000. Consequently, cormorants from these three colonies consumed 40.7 million fish. These estimates are similar to those reported in 1999 for these three colonies (39.9 million fish).

   The number of cormorants along the St. Lawrence River corridor has increased markedly since the early 1990s (i.e., 38 nests on a single colony in 1992) to over 900 nests on three colonies in 2000. Yellow perch was the major prey fish from the Griswold Island colony. Rock bass (37.7%) and yellow perch (33.3%) were the 1st  and 2nd  most abundant prey from McNair island. Yellow perch dominated the diet of Strachan Island cormorants (61.6%).

   The abundance of yellow perch in the eastern basin of Lake Ontario declined over the past two decades. Despite the production of some of the strongest year classes on record in the early 1990s, the abundance of age-3 and older yellow perch has not increased. At least three environmental variables could have potentially contributed to increased mortality of yellow perch: declining productivity, increased walleye abundance, and increased cormorant abundance.