USGS · 70040751
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
P. E. Greeson, G.S. Meyers. 1969. The limnology of Oneida Lake-An interim report. https://pubs.usgs.gov/publication/70040751
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Each year we report on the progress toward rehabilitation of the Lake Ontario lake trout ( Salvelinus namaycush ) population, including the results of stocking, annual assessment surveys, creel surveys, and evidence of natural reproduction observed from all standard surveys performed by USGS and NYSDEC. The catch per unit effort of adult lake trout in gill nets increased each year from 2008-2014, recovering from historic lows recorded during 2005-2007. Adult abundances declined each year from 2015 to 2017; and in 2017 were about 35% below the 2014 peak and 17% below the 1999-2004 mean. Adult abundance increased in 2018 by 51% over the 2017 value and increased and addition 16% in 2019. The 2019 rate of wounding by sea lamprey (Petromyzon marinus) on lake trout caught in gill nets (0.53 A1 wounds (fresh wound) per 100 lake trout) was below target (2 wounds per 100 lake trout). Estimates from the NYSDEC fishing boat survey indicated angler catch rate of lake trout was low in 2019 and among the lowest recorded for the time series. Condition values for an adult lake trout, indexed in September from the predicted weight for a 700mm lake trout from annual length-weight regressions and Fulton’s K for age-6 males, were among the highest levels observed for the 1983-2019 time series. Predicted weight for a 400mm lake trout from July 2019 bottom trawl catches was near the long-term average while age-2 K was among the lowest for the time series. Reproductive potential for the adult stock indexed from the CPUE of mature females ≥ 4000g was again above the target in 2019 continuing a trend observed in nine of the last ten years. The 2019 catch of young native lake trout marked the 25th observation in the last 26 years, however the low numbers of native adults observed during that time period continues to indicate substantial restoration impediments still exist.
In Lake Ontario, lake trout restoration efforts have not established a self-sustaining population. Herein we describe efforts to evaluate standard and new surveys, and to estimate dispersal from stocking locations, to better understand impediments to natural reproduction. In 2019, lake trout egg deposition was sampled at two locations, Stony Island Reef, and Ford Shoals. No eggs were collected at either site. Egg deposition rates at Stony Island Reef, expressed in eggs/net/day, were lower in 2019 (0) and 2017 (0.0004) than in 1987 and 1989 (1.27 and 0.27, respectively). Spawning lake trout were indexed using standard gillnets set at six locations along the southern shore. Sites were fished overnight with two nets, except Youngstown where only one net was set. When comparing the standard September gillnet survey to the spawning survey, the spawning survey caught more and older fish, but had a similar representation of strains. Both gillnet surveys revealed that, during the early to late fall, most lake trout (>72%) are caught as adults near where they were stocked as juveniles. This spawning survey demonstrated that lake trout in spawning condition are aggregating near possible spawning habitat, but the presence of adults alone cannot identify the specific spawning habitat. Egg deposition results suggest lake trout may be depositing eggs in different habitats then they have in the past. Alternatively, our egg collection methods may not be effective when egg abundance is low. Lake Ontario lake trout restoration would benefit from survey approaches that identify specific spawning habitat.
Explore the source record for details and available documents.