TIPSHEET
From safe dam passage for sturgeon to a long-term study of the Eastern striped bass, USGS scientists will present a wide range of fisheries research at the annual meeting of the American Fisheries Society, at the Hartford Civic Center, Hartford, Conn, Aug. 23-27, 1998.
Dinosaurs and Sturgeon in the Connecticut River--Mon., Aug. 24, session 6
Shortnose sturgeon and Atlantic sturgeon are native to the Connecticut River. Because of their ancient origin, it is estimated that they could have inhabited the Connecticut Valley at the time of the dinosaurs during the Cretaceous period. The study examines the impact of human activity on sturgeon populations since colonial days. Factors ranging from dam construction to over fishing diminished this fishery and by the 1940's, the population had virtually disappeared in some areas of the watershed. ("The History of Sturgeon in the Connecticut River," by Boyd Kynard, USGS, Turners Falls, Mass.; and Tom Savoy, Connecticut Department of Environmental Protection, Old Lyme, Conn.)
Telemetry, Eels and Dams--Mon., Aug. 24, session 12
Most people think of fish migration when dealing with the obstacles presented by dams. But developing ways for silver phase American eels to safely swim around dams is a critical problem for the species' survival, because they typically suffer high mortality from passing through hydroelectric turbines during their spawning migration to the ocean. Over a two-year period, researchers using radio and acoustic telemetry devices monitored the migration and behavior of the eels near a hydroelectric dam. Most eels moved through the dam area at night at a variety of depths, and some were delayed for several days before passing the dam. The results of the study will be critical for developing effective eel passage technologies. ("Behavior and Passage of Silver-Phase Eels at a Small Hydroelectric Facility," by Alex Haro, S.O. Conte Anadromous Fish Research Center, USGS, Turner Falls, Ma.)
Striped Bass Tagging and Harvest Regulations--Tues., Aug. 25, session 7
A long-term study of nearly 175,000 tagged striped bass on the East Coast revealed that fish survival rates are affected by changes in harvest regulations and that some of these rates are modified by factors such as fish age and sex. Since 1987, wild striped bass have been tagged in a east coast-wide study involving fifteen state and federal agencies. Data from three long-term tagging programs were used to assess the impact of substantial regulatory changes that took place from 1987 to 1998. ("Atlantic Striped Bass Survival And Harvest Regulation: An Analysis of Coast Wide Tag-Recovery Data," by David Smith, USGS, Kearneysville, W.Va., Xi He, Massachusetts Division of Marine Fisheries, Gloucester, Mass.; Victor Vecchio, New York State Department of Environmental Conservation, East Setauket, N.Y.; Cynthia Goshorn, Maryland Department of Natural Resources, Annapolis, Md; Andrew Kahnle, New York State Department of Environmental Conservation, New Paltz, N.Y.; Tina McCrobie, U.S. Fish and Wildlife Service, Annapolis, Md.)
PCB Concentrations in Walleyes--Tues., Aug. 25, session 16 Walleye adult males in Saginaw Bay, which drains into Lake Huron, have significantly higher concentrations of PCBs than females, a recent study reveals. The higher concentrations in males are probably because they spend more time in contaminated areas of the watershed than females. ("Sexual Difference in PCB Accumulation Rates of Walleye," by C.P. Madenjian, USGS, Ann Arbor, Mich. ; G.E. Noguchi, U.S. Fish and Wildlife Service, Arlington, Va; R.C. Haas, Michigan Department of Natural Resources, Mt. Clemens, Mich.; K.S. Schrouder, Michigan Department of Natural Resources, Bay City, Mich. )
Identifying Genetic Diversity in Sturgeon Utilizing DNA Markers--Wed., Aug. 26, session 5 A petition to add the anadromous Atlantic sturgeon to the federal threatened species list has prompted USGS scientists to develop species-specific DNA markers to aid in the understanding of gene mixing among sturgeon sub-populations. This is vital to proper management of genetic diversity. Specific nuclear DNA markers dubbed "microsatellites" are among the most useful that researchers have developed. These markers have identified a significant amount of previously undetected genetic variability that has proven useful in identifying subpopulations in sturgeon species. ("Conservation Genetics of Atlantic Sturgeon: Identification and Management of Genetic Diversity," by Barbara A. Lubinski, USGS, and Tim L. King, Kearneysville, W.Va.)
Safe Dam Passage For Lake Sturgeon--Wed., Aug. 26, session 5
The potential opening of Great Lakes rivers such as the Wolf and Menominee Rivers in Wisconsin to migration of native fishes means that fish passage facilities for dams will be needed. They must allow fish passage even for fish with the poorest passage success such as the lake sturgeon. Scientists simulated river- flow using model technology and behavioral experiments to determine the best design of fish passage structures. ("Studies on Fish Passage of Lake Sturgeon," by Boyd Kynard and Martin Horgan, USGS, Turner Falls, Mass.; Eric Theiss, Los Angeles, Calif; Tom Thuemler, Wisconsin Department of Natural Resources, St., Pestigo, Wisc.; Douglas Cox, Menominee Indian Tribe of Wisconsin, Keshena, Wisc.; Jim Fossum, U.S. Fish and Wildlife Service, Green Bay, Wisc.; Gary Whelan, Michigan Department of Natural Resources, Lansing, Mich.)
Identifying Genetic Variation in Atlantic Salmon--Wed., Aug. 26, session 7
Findings of a recent study indicate that North American salmon generally exhibit less genetic diversity than their European counterparts. Microsatellite (nuclear DNA) and mitochondrial (extra-nuclear DNA) markers have been developed and used to assess genetic population structure in Atlantic salmon surveyed from throughout the species' range. In particular, salmon from Maine (southern extent of North American range) were compared to fish from northern Spain (southern extent of European range). ("Microsatellite and Mitochondrial DNA Variation in DNA Variation in Atlantic salmon," by Tim L. King and Barbara Lubinski, USGS, Kearneysville, W.Va.)
Threatened Neosho Madtom Population Decreasing--Thur., Aug. 27, session 9
General population trends indicate that the Neosho madtoms, a federally-listed threatened fish species since 1990, are decreasing in two of their three Midwestern river habitats -- the Neosho and Cottonwood rivers. Although the Spring River, their third habitat, had only a remnant population in 1990, the Neosho and Cottonwood rivers had modest madtom populations. Scientists speculate that the small, bottom-feeding, Nesosho madtom is the victim of a decline in habitat quality. Having monitored Neosho madtom populations and habitat features in the Neosho and the Cottonwood rivers since 1991, scientists believe that the best management strategy for sustaining the population is to improve habitat conditions. ("Population and Community Trends of the Federally-Listed Neosho Madtom," by M.L. Wildhaber and A. Allert, USGS, Columbia, Mo. and P. J. Lamberson, Columbia, Mo.; V.M. Tabor, and D. Mulhern, U.S. Fish and Wildlife Service, Manhattan, Kan.; K. L. Powell, Westwood Professional Services, Eden Prairie, Minn.)
Working Toward a Healthy Rainbow Trout Population in Katmai National Park, Alaska--Thur. Aug. 27, session 11
Researchers used a combination of external tags, radio telemetry, and size data to determine that there are multiple and distinct rainbow trout populations in different locales in the Alagnak watershed, and that they exhibit distinct seasonal movement patterns based principally on temperature and food supply. The study was prompted by recent concerns raised about the health of the prized rainbow populations of the Alagnak Wild River and its tributaries upstream in Katmai National Park. Before the health status of populations can be assessed, these basic questions about population structure and movement had to be addressed. This early work is helping to establish a new model for rainbow trout population structure and movement patterns that may be applicable to most of Southwest Alaska. ("Alagnak Watershed Rainbow Trout Investigations," by E. Eric Knudsen, USGS, Anchorage, Ak., and Robert B. Benter, U.S. Fish and Wildlife Service, Anchorage, Ak.)