Ferruginous Duck (Aythya nyroca) Science Article 1 abstract Diurnal time-activity budgets were quantified for Ferruginous Pochard Aythya nyroca wintering in Tanguar Haor, Bangladesh. Individuals spent most time resting (60%), with less time spent feeding (17%), preening (14%) and swimming (9%). The time spent feeding was generally lower than for other Aythya species in winter, perhaps […]
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DIVING BEHAVIOUR AND HEART RATE IN TUFTED DUCKS (AYTHYA FULIGULA)
Tufted Duck (Aythya fuligula) Science Article 2 abstract Diving behaviour and heart rate were monitored in tufted ducks diving under circumstances which simulated various environmental conditions such as feeding under ice in winter R. STEPHENSON et al., J. exp. Biol. 126, 341-359 (1986) Download article download full text (pdf)
Food intake rates and habitat segregation of Tufted Duck Aythya fuligula and Scaup Aythya marila exploiting Zebra Mussels Dreissena polymorpha.
Tufted Duck (Aythya fuligula) Science Article 1 abstract The foraging skills of Tufted Duck Aythya fuligula and Scaup Aythya marila feeding on Zebra Mussels Dreissena polymorpha were studied in experiments under semi-natural diving conditions with relevance to the IJsselmeer/Markermeer area (large lakes in the centre of The Netherlands, former Zuiderzee area), the major freshwater wintering […]
Record of a Redhead, Aythya americana, laying eggs in a Northern Harrier, Circus cyaneus, nest
Redhead (Aythya americana) Science Article 5 abstract Alberta; Anatidae; Aythya americana; Circus; Circus hudsonius; egg; egg description; eggs; laying; nest; nest parasitism; Northern Harrier Fleskes,J. P, Canadian Field-Naturalist 106:263-264. Download article download full text (pdf)
SALT GLAND DEVELOPMENT IN MIGRATORY REDHEADS(AYTHYA AMERICANA) IN SALINE ENVIRONMENTS ON THEWINTER RANGE, GULF OF MEXICO, USA
Redhead (Aythya americana) Science Article 3 abstract Redheads (Aythya americana) migrate annually from their breeding range in the interior ofNorth America to winter along the coasts of the United States and Mexico. Two of the mostimportant areas where redheads traditionally concentrate in winter are the Laguna Madre andnearby bays in southern Texas and the Chandeleur […]
Survey for Blood Parasites in Redheads (Aythya americana) Wintering at the Chandeleur Islands, Louisiana
Redhead (Aythya americana) Science Article 1 abstract We detected no infections with species of Plasmodium, Haemoproteus, Leucocytozoon,Sarcocystis or Trypanosoma in blood smears, liver and spleen impressions, and muscle tissue from 136 redheads (Aythya americana) collected or captured at the ChandeleurIslands, Louisiana (USA), during three winters (1987 to 1990). Thomas C. Michot, Journal of Wildlife Diseases, […]
Wetland Salinity and Salt Gland Size in the Redhead Aythya americana
Redhead (Aythya americana) Science Article 4 abstract Numerous investigators have shown experimentally that nasal or supraorbital salt glands exist in nonmarine waterfowl and have the ability to enlarge or atrophyi n responset o changesin the salt content of the drinking water (Scothome 1959, Ellis et al. 1963, Cooch 1964, Benson and Phillips 1964, Schmidt-Nielsen and […]
FOOD HABITS OF REDHEADS (AYTHYA AMERICANA) WINTERING IN SEAGRASS BEDS OF COASTAL LOUISIANA AND TEXAS, USA
Redhead (Aythya americana) Science Article 2 abstract Diets of wintering redheads (Aythya americana) have been studied in the past, but none of theprevious studies compared diets of the upper gastrointestinal tract to determine if they differeddue to sex, age, location, year, or time of year. MICHOT, T. C et al, Acta Zoologica Academiae Scientiarum Hungaricae […]
Intersexual differences in feeding ecology in a male dominated wintering Pochard Aythya ferina population.
Pochard (Aythya ferina) Science Article 1 abstract Intersexual differences in feeding rates, aggression rates, an d feeding site selection were investi gated in a flock of up to 2700 Pochard Aythya ferina wintering at Salford docks, Greater M anchester (239 males per 100 females) . As often found elsewhere, females were less aggressive than males, […]
Food intake rates and habitat segregation of Tufted Duck Aythya fuligula and Scaup Aythya marila exploiting Zebra Mussels Dreissena polymorpha.
Greater Scaup (Aythya marila) Science Article 1 abstract The foraging skills of Tufted Duck Aythya fuligula and Scaup Aythya marila feeding on Zebra Mussels Dreissena polymorpha were studied in experiments under semi-natural diving conditions with relevance to the IJsselmeer/Markermeer area (large lakes in the centre of The Netherlands, former Zuiderzee area), the major freshwater wintering […]