Freshwater Fishing News

NOAA’s Fisheries Service has announced $12.6 million in grants through the Protected Species Cooperative Conservation Grant Program to assist 19 states and territories with conservation projects designed to recover marine mammals, sea turtles, fish, coral and other species listed under the Endangered Species Act.

Several proposals selected during the fiscal year 2010 grant cycle will help sturgeon populations including:

Delaware Division of Fish and Wildlife ($1,019,486): To determine habitat requirements and migratory pathways to provide managers with essential information to recover Atlantic and shortnose sturgeon in Delaware, New Jersey and Connecticut.

Maine Department of Marine Resources ($315,330): To determine spatial distribution, key habitat, and movement patterns of shortnose and Atlantic sturgeon among Maine rivers and nearby states to inform management and recovery actions.

Mississippi Department of Wildlife, Fisheries and Parks ($297,714): To identify feeding habitat for and movement of juvenile and sub-adult Gulf sturgeon in the state’s Pascagoula River estuary.

New York Department of Environmental Conservation ($1,325,437): To collaborate with Maine, Connecticut and New Jersey partners in determining Atlantic sturgeon habitat use and movement throughout the Mid-Atlantic Bight and evaluating spatial strategies to minimize Atlantic sturgeon bycatch.

South Carolina Department of Natural Resources ($1,800,800): To determine shortnose and Atlantic sturgeon movements and habitat use with North Carolina partners to inform regional conservation efforts.

Washington Department of Fish and Wildlife ($576,668): To collaborate with the Oregon Department of Fish and Wildlife in tracking coast-wide status and trends of green sturgeon and managing human caused impacts to the species.

source: NOAA press release

The Potomac River in Washington, D.C. is showing multiple benefits from restoration efforts, newly published research suggests.  Reduced nutrients and improved water clarity have increased the abundance and diversity of submerged aquatic vegetation (SAV) in the Potomac, according to direct measurements taken during the 18-year field study.

Since 1990, the area covered by SAV in the lower Potomac has doubled, the area covered by native SAV has increased ten-fold, the diversity of plant species has increased, and the proportion of exotic species to native species has declined as nutrients have declined, according to the study by the U.S. Geological Survey and England’s National Oceanography Centre (NOC) in Southhampton, UK.

More than a dozen species of SAV, including the exotic hydrilla, co-exist in this reach of the Potomac that was almost barren in a 1978-1981 USGS study.

SAV are critical to the ecosystem in the Chesapeake Bay and its tributaries. They provide oxygen, food, and shelter so that invertebrates, fish, crabs and waterfowl can survive.  High nutrient levels stimulate algal blooms in the water, decrease water clarity, and block light needed for SAV growth.

The authors analyzed measurements of aquatic plant species abundance, nutrient effluent from the wastewater treatment plant, and water quality from 1990 to 2007. The surveys included a 50-mile reach of the tidal Potomac downstream from Washington.

Key Findings on the Potomac River’s SAV:

- Native SAV cover increased tenfold from 288 to 3081 acres.

- The overall area covered by SAV in the Potomac more than doubled since 1990, increasing from 4207 to 8441 acres.

- The diversity of SAV has increased. In 1990 the exotic hydrilla was 10 times more abundant than any other species. In 2007 the abundance of the 7 most frequently occurring species are more evenly matched.

- In 1990, more than 80% of the total SAV was hydrilla; in 2007 hydrilla declined to 20%.

- Results suggest declining fitness of exotic species relative to native species during restoration.

These results are consistent with a multi-agency study released in July, which correlated nutrient reductions with gains in the abundance of SAV in some Chesapeake Bay tributaries, while noting a negative correlation within the bay between SAV and nitrogen.

The study was supported by USGS National Research Program; U.S. Army Corps of Engineers, Baltimore; the Metropolitan Washington Council of Government’s Aquatic Plant Management Program; and the Fisheries Division of the District of Columbia Department of Health.

The report, “Long-term reductions in anthropogenic nutrients link to improvements in Chesapeake Bay habitat is published in the Proceedings of the National Academy of Science. http://www.pnas.org/cgi/doi/10.1073/pnas.1003590107.

source: USGS press release

Research by a University of Florida expert suggests that anglers do not harm largemouth bass populations when practicing catch and release fishing during the spawning season.

In Florida, the bass usually begin spawning in January or February in 2010 they started at least a month late, said Mike Allen, a fisheries professor with UF’s Institute of Food and Agricultural Sciences.

Largemouths are the state’s most popular freshwater game fish. To spawn, male bass make shallow nests in the sand, court females, and then protect the eggs and hatchlings for several weeks.

Males guarding nests are notoriously aggressive, striking anything that moves. The fish are easy to catch, but it’s commonly believed that spawning-season fishing reduces bass populations. Allen’s latest study suggests that notion is rarely true.

The findings were published in the journal Transactions of the American Fisheries Society.

“We found that in most cases, spawning area closures won’t improve bass populations, for a couple of reasons,” he said. “One is, there’s a lot of catch and release nowadays. The other is, if you lose some nests, the ones that are left have higher survival rates.”

Catch and release is the practice of setting fish free, rather than keeping or “harvesting” them. In 2008, Allen and colleagues published a study showing that the percentage of largemouth bass harvested by anglers had fallen by half since the 1980s.

When nesting male bass are harvested — or if they’re released after a long delay — their nests are likely to be invaded by predators such as bluegill, which gobble up eggs and hatchlings.

However, the young bass that survive face less competition for food and shelter, giving them a better chance at reaching adulthood, Allen said.

The study used mathematical models to predict changes in two types of bass populations. One was typical of southern states, with fast growth rates, early maturation and high natural mortality. The other had the opposite qualities, typical of northern states.

Allen and biological scientist Daniel Gwinn, the study’s other author, gathered data on anglers catching bass during spawning seasons in three states. The researchers plugged the data into mathematical models representing several types of restricted and unrestricted fishing.

The results showed that prohibiting bass fishing during spawning season would only boost populations in waters where very high percentages of spawning bass are caught.

“Those conditions are pretty rare,”Allen said.

To test his findings in the field, Allen is collaborating with researchers from the Illinois Natural History Survey. They’ll catch nesting bass in two Florida lakes and four Canadian lakes to see if it influences the number of young that reach adulthood.

If there is no decrease, some officials might want to reconsider their policies, Allen said.

Wildlife managers in some northern states prohibit bass fishing during spawning, arguing that it protects bass populations. Local anglers don’t always agree, he said.

In Florida, no spawning-season restrictions on largemouth bass are likely, Allen said. But the study may have implications for proposed fishing restrictions on other species.

“This research shows that protecting fish just to let them spawn won’t improve sustainability,” Allen said. “If overfishing happens, we will need a larger closing to reduce annual fishing-related mortality — closing over a longer time or a larger area.”

source: University of Florida

Agriculture Secretary Tom Vilsack and Interior Secretary Ken Salazar have announced joint scientific research projects that address the effects of climate change on freshwater systems and sensitive aquatic species in the northwestern and southeastern United States.

“Addressing the challenges of climate change will require new tools that enable our leaders to develop successful strategies,” said Vilsack. “This research will provide tools and information to help ensure that aquatic ecosystems in the Northwest and Southeast remain healthy in the face of climate change.”

“Conserving our nation’s fisheries and aquatic ecosystems will be a challenge as climate change continues,” said Salazar. “These collaborative research projects will provide the science and technology needed by the Interior Department and other natural resource managers to plan for coping with these challenges, especially in sensitive aquatic environments.”

Salazar noted that these projects are an early indication of the kind of science and management support that will be generated by the Interior Department’s regional climate science centers, which will be established in the Northwest and Southeast later this year. “Collaborative science targeted at managers needs is our agenda,” Salazar said.

The multi-year $500,000 joint USDA-DOI projects, which will be carried out by U.S. Geological Survey (USGS) and U.S. Forest Service (USFS) scientists, will make use of existing data, field studies and modeling to better understand the effects of climate change on aquatic ecosystems. Information from the project will help guide science-based land-use decisions by federal agencies and others engaged in long-term planning for climate adaptation.

In the Northwest, a region known for its abundant supply of cold and clean fresh water, the project’s goal is to identify how climate change will affect water temperature, quality and quantity, as well as the likely effects of increasing and more fluctuating water temperatures on coldwater-dependent fish such as trout and salmon.

Regional climate change will likely cause altered hydrology and water temperatures, vital components of water quality and healthy life cycles for species such as Pacific salmon, trout and chars, which depend on coldwater habitats. At the same time, little is known about existing and potential impacts of climate change for stream temperature in the Pacific Northwest. With a better understanding these factors – temperature and altered water flows – experts will be able to help guide land-use decisions by federal and state agencies planning for climate adaptation in the area.

In the Southeast, the project’s goal is to develop tools managers can use to minimize the effects of climate change on aquatic ecosystems and the coldwater-dependent species in them, as well as on related ecosystem service such as drinking water quality and wildlife-based recreation. The scientists will refine and combine climate and hydrologic models for the region that will help resource professionals assess how land-use and water-management decisions will affect coldwater fish species such as brook trout, and the transition from coldwater fisheries in the mountains to warm water fisheries in the lower-lying Piedmont area.

source: USDA

Biologists from the Oregon Department of Fish and Wildlife will sample the Crooked River below Bowman Dam for redband trout and mountain whitefish beginning Monday, June 14 through Thursday, June 17.

Biologists will be electrofishing the river between Big Bend and Cobble Rock campgrounds. Electrofishing uses an electric current to stun the fish so biologists can net them to record the size, condition and abundance of both redband trout and mountain whitefish. The fish are then released unharmed.

“Fishing will be adversely affected in this area during the four days of sampling, but anglers can expect the good fishing to return by Saturday, June 19,” said Mike Harrington, ODFW fish biologist. “Fishing in the lower five miles of the Wild and Scenic section of the river won’t be affected at all.

A study being conducted by Oregon State University is in its final stages and sampling will be less intense this year, Harrington said,  Last year’s population estimates show increased numbers of redband trout in the river, which is supported by angler reports of “great fishing,” he added.

ODFW began sampling the Crooked River in 1989 in order to track the long-term health of the redband trout population.  During the sampling fish are tagged with a numbered floy tag protruding from the back and then released.  Anglers who later catch a trout or whitefish with a floy tag are encouraged to release the fish after recording the tag number, fish length and location caught.  Anglers can send the information to ODFW at (541) 447-5111 ext. 24 or michael.r.harrington@state.or.us.  The information will then be used to track fish growth and movements.

Anglers can also expect to encounter an ODFW creel surveyor on the portion of the Crooked River directly below Bowman Dam this summer.  According to Harrington, the creel is designed to compare the population estimates gathered by biologists with the success rate of anglers trying to catch fish. Anglers will be asked about the number of fish caught, species, average size and fin clips.  This information, paired with biological data being collected by ODFW and Oregon State University, will help to improve management of the Crooked River fishery.

source: Oregon Department of Fish and Wildlife