Varied Thrush (Ixoreus naevius) Science Article 2 abstract From a study of a partially albino female Varied Thrush, certain inferences are suggested with regard to sex coloration, principal of which is that, in Ixoreus, the sex difference in pigmentation is quantitative rather than qualitative. J. EUGENE LAW, THE CONDOR Vol. 23, 1931 Download article download […]
Occurrence of Collyriclum taba (Trematoda) in a Varied Thrush with a note on a single bird’s internal parasites
Varied Thrush (Ixoreus naevius) Science Article 3 abstract parasites.–A Varied Thrush (Ixoreus naevlus) was obtained on 18 November 1960, near Woods Creek, Benton County, Oregon. The bird was infected with 14 mature Collyriclum faba. The flukes were in pairs, in subcutaneous cysts adjacent to the anus. The paired flukes were not equal in size. ALBERT […]
UPLAND SANDPIPER ASSESSMENT
Upland Sandpiper (Bartramia longicauda) Science Article 1 abstract Since 1968, the Maine Department of Inland Fisheries and Wildlife (MDIFW) has developed and refined wildlife species assessments to formulate management goals, objectives, and strategic plans. Assessments are based upon available information and the judgments of professional wildlife biologists responsible for individual species or groups of species. […]
Natal philopatry and local movement patterns of Twite Carduelis flavirostris
Twite (Carduelis flavirostris) Science Article 2 abstract The Twite Carduelis flavirostris is classified as a red-listed bird of conservation concern in the United Kingdom. Successful conservation initiatives will depend on an understanding of local movement patterns and natal philopatry as these will be important in determining how likely the species is to colonise new nesting […]
Migration patterns of two populations of Twite Carduelis flavirostris in Britain
Twite (Carduelis flavirostris) Science Article 1 abstract Following a recent large decline in range and numbers, the Twite Carduelis flavirostris is a red-listed bird of conservation concern. An understanding of the species’ movements between wintering and breeding areas is essential to underpin effective conservation. The migration patterns of two populations of Twite were examined: those […]
Nonlinear phenomena and song evolution in Streptopelia doves
Turtle-Dove (Streptopelia turtur) Science Article 1 abstract The production of complex bird song is commonly achieved through neuromuscular activity of respiratory,syringeal and craniomandibular systems. According to nonlinear dynamics theory, however, complexity can also emergespontaneously from very simple and deterministic systems, without any external control. Thus far, studies linking bird songcomplexity with nonlinear dynamics are very […]
OLFACTORY SENSITIVITY OF THE TURKEY VULTURE (CATHARTES AURA) TO THREE CARRION-ASSOCIATED ODORANTS
Turkey Vulture (Cathartes aura) Science Article 2 abstract The Turkey Vulture (Cathartes aura) is generally thought to rely on olfactory cues to locate carrion. Because vertically rising odorants are dispersed rapidly by wind turbulence, we predict that Turkey Vultures should be highly sensitive to these chemicals to detect them at foraging altitudes. Olfactory thresholds to […]
Observations on Migratory Turkey Vultures and Lesser Yellow-headed Vultures in Northern Colombia
Turkey Vulture (Cathartes aura) Science Article 1 abstract Turkey Vultures (Cathartes aura) breed from southern Canada to Tierra del Fuego, while Lesser Yellowheaded Vultures (Cathartes burrovianus) occur from M xico through Central America to northern Argentina and Uruguay (Meyer de Schauensee 1966).It has long been known that Turkey Vultures breeding in the northern parts of […]
Nestling growth and parental provisioning of Tufted Puffins (Fratercula cirrhala) on Triangle Island, British Columbia
Tufted Puffin (Fratercula cirrhata) Science Article 1 abstract I studied the reproductive performance of tufted puffins (Fratercula cirrhata) on TriangleIsland, British Columbia during two years when reproduction was successful. Completereproductive failures are common for this population. I report on the timing of breeding, nestling growth, fledging behaviour, nestling diet, and parental provisioning, and discuss the […]
Ornaments and overflight behaviour of Tufted Puffins (Fraterculacirrhata) breeding on Triangle Island, British Columbia.
Tufted Puffin (Fratercula cirrhata) Science Article 3 abstract Tufted puffins (Fratercula cirrhata) are unusual among seabirds in that they bearmultiple colourful ornaments during the breeding season. They also engage in colony overflights when approaching the colony with food for their chicks. Blackburn, G., Simon Fraser University, Burnaby, BC. 74 pp Download article download full text […]