Grey Plover (Pluvialis squatarola) Science Article 1 abstract Grey plovers wintering at different latitudes differ in duration of molt. We investigated the role of simultaneous primaryshedding and different growth rates of individual primaries on regulation of molt speed. We also explored relationships betweenlength and mass of primaries and primary growth rates. Grey plovers adjusted molt […]
Category: North America
Behaviours influencing the distribution of great blue herons (ardea herodias fannini) in the strait of Georgia, British Columbia
Great Blue Heron (Ardea herodias) Science Article 14 abstract The Great Blue Heron (Ardea herodias fannini), a nonmigratory subspecies endemic to the Pacific Northwest of North America, is COSEWIC-listed in Canada as a species of ‘special concern’. The Breeding Bird Survey (BBS), conducted since 1969, indicate an ongoing decline in numbers. Recent findings show that […]
Migration patterns of cedar waxwings in the eastern United States
Cedar Waxwing (Bombycilla cedrorum) Science Article 6 abstract No abstract BRUGGER, K. E., L.N. ARKIN, AND J.M. GRAMLICH, Journal of Field Ornithology 65:381-387, 1994 Download article download full text (pdf)
Male traits, mating tactics and reproductive success in the buff-breasted sandpiper, Tryngites subruficollis
Buff-breasted Sandpiper (Tryngites subruficollis) Science Article 1 abstract Buff-breasted sandpipers use a variety of mating tactics to acquire mates, including remaining at a singlelek for most of the breeding season, attending multiple leks during the season, displaying solitarily ordisplaying both on leks and solitarily. We found that differences in body size, body condition, fluctuatingasymmetry scores, […]
Conservation status of the buff-breasted sandpiper:historic and contemporary distribution andabundance in south america
Buff-breasted Sandpiper (Tryngites subruficollis) Science Article 2 abstract We present historic and contemporary information on the distribution and abundance of BuffbreastedSandpipers (Tryngites subruficollis) in South America. Historic information was collated from the literature,area ornithologists, and museums, whereas contemporary data were derived from surveys conducted throughoutthe main wintering range in Argentina, Uruguay, and Brazil during the […]
Factors affecting how male and female bobolinks apportion parental investments
Bobolink (Dolichonyx oryzivorus) Science Article 7 abstract Male and female Bobolinks (Dolichonyx oryzivorus) adjust the amount of time spent brooding and provisioning nestlings at primary nests in light of prevailing weather conditions and food availability. Males brood nestlings less and feed them more (mg/h) when food is scarce, regardless of weather conditions. Primary (i.e., first-mated) […]
Does the avian ophthalmic nerve carry magnetic navigationalinformation?
Bobolink (Dolichonyx oryzivorus) Science Article 3 abstract The bobolink (Dolichonyx oryzivorus) uses the earth’s magnetic field as one source of directional information for its migratory orientation. However, the location and structure of the magnetoreceptors that transduce the magnetic information to the nervous system are unknown. Because treatment with a strong magnetic pulse results in a […]
Photoperiodism and the annual testicular cycle of the bobolink (dolichonyx oryzivorus), a trans equatorial migrant, as compared with two temperate zone migrants
Bobolink (Dolichonyx oryzivorus) Science Article 5 abstract It is now quite generally accepted that seasonal changes in day-length play animportant role in the temporal regulation of several annual cyclic phenomena inmany birds of the northern hemisphere. Best known is the effect of photoperiodson the annual cycle of the testes, but evidence is accumulating that there […]
Spatial responses of bobolinks (dolichonyx oryzivorus)near different types of edges in northern iowa
Bobolink (Dolichonyx oryzivorus) Science Article 2 abstract Habitat edges are well-studied components of fragmented landscapes, yet factorsmediating edge effects remain unclear. We report how different types of edges surroundingpatches may affect spatial distributions of Bobolink (Dolichonyx oryzivorus), a declining, area-sensitive songbird that breeds in grasslands. We expected Bobolinks to be less abundant near edges, and […]
Preliminary Study in whether land management affects dialect formation in Bobolinks
Bobolink (Dolichonyx oryzivorus) Science Article 4 abstract Song dialects occur when individuals share similarity in song phrases at the group level. Most hypotheses regarding formation and maintenance of dialects attempt to explain how females select mates through preferences for local song types (Payne et al. 1981; Baker & Cunningham 1985; Rothstein & Fleischer 1987). Anastasia […]