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At least 55 records · Page 3Linked to original sources

Effects of bottom fishing on the benthic megafauna of Georges Bank

This study addresses ongoing concerns ever the effects of mobile fishing gear on benthic communities. Using side-scan sonar, bottom photographs and fishing records, we identified a set of disturbed and undisturbed sites on the gravel pavement area of northern Georges Bank in the northwest Atlantic. Replicate samples of the megofauna were collected with a 1 m Naturalists' dredge on 2 cruises in 1994. Compared with the disturbed sites, the undisturbed sites had higher numbers of organisms, biomass, species richness and species diversity; evenness was higher at the disturbed sites. Undisturbed sites were characterized by an abundance of bushy epifaunal taxa (bryozoans, hydroids, worm tubes) that provide a complex habitat for shrimps, polychaetes, brittle stars, mussels and small fish. Disturbed sites were dominated by larger, hard-shelled molluscs, and scavenging crabs and echinoderms. Many of the megafaunal species in our samples have also been identified in stomach contents of demersal fish on Georges Bank; the abundances of at feast some of these species were reduced at the disturbed sites.

Marine Ecology Progress Series

Seasonal habitat use of brook trout and juvenile Atlantic Salmon in a Tributary of Lake Ontario

The seasonal habitat use of Salvelinus fontinalis (Brook Trout) and sub-yearling Salmo salar (Atlantic Salmon) was examined in Hart Brook, a tributary of Lake Ontario. Fish habitat use and available habitat were examined during summer and autumn. Interspecific differences in habitat use occurred as well as intraspecific seasonal differences. Overyearling Brook Trout were more selective in their habitat preferences than subyearling Brook Trout or juvenile Atlantic Salmon. Depth and the amount of cover were significantly different among the three fish groups. Salmon occupied faster and shallower water than either age group of trout. Atlantic Salmon were also associated with larger-sized substrate materials than either trout age group, and salmon occurred in habitats with less cover than trout. Overyearling Brook Trout occupied deeper water with more cover than subyearling trout. All three salmonid groups occupied areas with more cover in autumn compared to summer. In autumn, subyearling Brook Trout used deeper areas than they had in the summer. In Hart Brook, the habitat of subyearling Atlantic Salmon can be generally characterized as riffles, the habitat of overyearling Brook Trout was deep pools with extensive cover (35%), and that of subyearling trout was any area with moderate flow and at least 20% cover. As efforts proceed to reintroduce Atlantic Salmon in Lake Ontario, further research is needed to ensure the conservation of Brook Trout populations.

New York

Population densities of painted buntings in the southeastern United States

The eastern population trend of Passerina ciris (Painted Bunting) declined 3.5% annually during the first 30 yrs of the Breeding Bird Survey (BBS, 1966&ndash;1996). Recently, the US Fish and Wildlife Service listed Painted Buntings as a focal species. Surveys for this focal species for the next 10 yrs (BBS, 1997&ndash;2007), however, are too low (<1 bird per 50 stops) for determining trend estimates. Also, to monitor densities adequately, surveys should account for incomplete detections. I surveyed singing Painted Buntings from 13 May to 26 June 2003 at 582 point counts (50 randomly selected transects) within blocks (64 × 64 km) in coastal and river areas from Florida to North Carolina. I compared densities of Painted Buntings for major habitats. Painted Buntings were detected at 33.5% of points surveyed for 5 min. Densities varied from 9 singing males per km 2 in young pine plantations to 42 per km 2 in maritime shrub. Effective detection radii for habitats varied from 64 to 90 m and were slightly higher in developed than in undeveloped habitats. Distance sampling is recommended to determine densities of Painted Buntings; however, large sample sizes (70&ndash;100 detections/habitat type) are required to monitor Painted Bunting densities in most habitats in the Atlantic coastal region of the southeastern United States. Special attention should be given to maritime shrub habitats, which may be important to maintaining the Painted Bunting population in the southeastern US.

Florida, Georgia, North Carolina, South Carolina

Northwestward range extension for Diacyclops harryi (Crustacea: Copepoda)

A recent find of the groundwater-inhabiting copepod crustacean Diacyclops harryi extended the known range of this species far northwestward, to include northern Ohio and the drainage basin of the Laurentian Great Lakes. The species was previously collected in drainages of the Atlantic Slope from New York to North Carolina. Ostracodes tentatively identified as ? Nannocandona n. sp., and amphipods belonging to the subterranean species Bactrurus mucronatus were also found at the Ohio locality.

Northeastern Naturalist

Who knew? First Myotis sodalis (Indiana Bat) maternity colony in the coastal plain of Virginia

We report the first confirmed Myotis sodalis (Indiana Bat) maternity colony in Virginia, discovered at Fort A.P. Hill Military Reservation in Caroline County along the Piedmont-Coastal Plain Fall Line. Acoustic surveys conducted in 2014 indicated likely presence of Indiana Bats on the installation. Subsequent focal mist-netting during May–June 2015 resulted in capture of 4 lactating females that we subsequently radio tracked to a maternity colony site containing at least 20 individuals. The core roosting-area was comprised of Pinus taeda (Loblolly Pine) snags with abundant exfoliating bark and high solar exposure. This forest patch was adjacent to a large emergentshrub wetland and within a larger matrix of mature, mid-Atlantic hardwood forests. The site where we found the colony location is 140 km east of the nearest known hibernaculum and is outside of the previously documented extent of this species' occurrence.

Virginia