Geology Reports⌕ Search

SEARCH · Geology Reports

Results for “Birding”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,711 records · Page 95Linked to original sources

Feeding flights of nesting wading birds at a Virginia colony

Feeding flights of Snowy Egrets (Egretta thula), Tricolored Herons (E. tricolor), Little Blue Herons (E. caerulea), and Cattle Egrets (Bubulcus ibis) were monitored at a small nesting colony near Chincoteague, Virginia during late May and June 1979. All four species varied their flight directions over a series of days. Cattle Egrets oriented in a different direction (toward uplands) from the other three wetland-feeding species, which oriented toward Spartina marsh areas. None of the species showed a tendency to form groups while departing from or arriving at the colony. Tide level had little influence on flight directions used. Comparisons are made between these results and those from a similar study in coastal North Carolina.

Virginia↗

Prevalence of eustrongylidosis in wading birds from colonies in California, Texas, and Rhode Island, USA

Snowy Egret (Egretta thula) and Black-crowned Night-Heron (Nycticorax nycticorax) nestlings from colonies in Texas, Rhode Island, and California and Great Egret (Casmerodius albus) nestlings from Texas were examined for eustrongylidosis, or infection by the parasitic nematode Eustrongylides spp. In 31% (24/77) of all broods examined, at least one nestling was infected. Snowy Egret broods from Texas were more frequently (100%) infected than those from California (20%) or Rhode Island (10%), and the prevalence of eustrongylidosis in 5- and 10-day-old Snowy Egret nestlings was higher in the Texas colony than the other two. Within the Texas colony, the frequency of eustrongylidosis was greater for Snowy Egret (100%) and Great Egret (80%) broods than for Black-crowned Night-Heron broods (12.5%). Also in Texas, eustrongylidosis was more frequent in 5-day-old Snowy Egret nestlings than 5-day-old Black-crowned Night-Heron or Great Egret nestlings, and in 10-day-old Snowy Egret nestlings than in 10-day-old Black-crowned Night-Heron nestlings. Eustrongylides spp. caused perforations of the gastrointestinal tract and peritonitis, particularly in Snowy Egrets.

California, Rhode Island, Texas↗

Iterative techniques for characterizing marine bird habitats with time-series of satellite images

Demonstrating long-term habitat use of marine habitats by seabirds is often complicated by short-term changes in habitat locations, persistence, and age. This paper describes iterative techniques for characterizing non-static habitats, such as meso-scale (10-100 km) ocean eddies and fronts, using time-series of satellite images that define sea surface conditions. Seabird use of satellite-detected habitats was compared using survey data and imagery from the Gulf of Alaska and southeastern United States. Time-series examination of satellite images combined with long-term seabird censuses allow 1) estimation of the successional state (age) of some marine habitats, 2) detection of recurring habitats, 3) geographically-referenced measurement of habitat location and areal extent, 4) identification of consistently-used habitats, and 5) demonstration of time-dependent use by seabirds associated with seasonal or annual variation in habitat availability.

Colonial Waterbirds↗