Scarlet Ibis (Eudocimus ruber) Science Article 2 abstract The reproductive biology of the Scarlet Ibis (Eudocimus ruber) and White Ibis (E. albus) is well known from sites in North America, the Caribbean, and the Venezuelan Ilanos, but few data are available on the status or breeding patterns of the populations that inhabit South American mangroves. […]
NESTING RECORDS OF FIVE ANTBIRD SPECIES FROM THECOLOMBIAN AMAZON
Scale-backed Antbird (Hylophylax poecilinotus) Science Article 1 abstract Few nests of Amazonian antbirds (Thamnophilidae and Formicariidae) have been described.Here we present nesting records for five species of antbirds found in Tinigua National Park, Colombia. A pouchshapedpensile nest of the Warbling Antbird (Hypocnemis cantator) in a treefall gap within seasonally floodedforest contained two eggs colored like […]
THE BEHAVIOR OF SCALE-BACKED ANTBIRDS
Scale-backed Antbird (Hylophylax poecilinotus) Science Article 2 abstract Among birds that regularly capture arthropods flushed by swarms of army ants in South American forests (Willis and Oniki 1978), one of the species lowest in peck orders is the Scale-backed Antbird (Hylophylux poecilinota). Here I report on the specialized behavior patterns that allow it to become […]
Seasonal and diel budgets of song: a study of Savi’s warbler( Locustella luscinioides)
Savis Warbler (Locustella luscinioides) Science Article 1 abstract Seasonal and diel patterns of singing activity of Savi’s warblers (Locustella luscinioides) were studied in two areas of Central Europe 300 km apart, over a period of 18 years. We assessed about 4,600 records of individuals singing. Males were found to exhibit similar singing activity in both […]
SUBSPECIFIC VARIATION IN WINTER POPULATIONS OF SPARROWS: A STUDY IN FIELD TAXONOMY
Savannah Sparrow (Passerculus sandwichensis) Science Article 9 abstract In 1951 an extensive area in Aiken and Barnwell counties, South Carolina, was selected as the site for the Savannah River Plant, whose genesis and general management fall within the province of the United States Atomic Energy Commission and whose construction, maintenance, and operation are due, in […]
THE FLEXIBLE MIGRATORY ORIENTATION SYSTEM OF THE SAVANNAH SPARROW (PASSERCULUS SANDWICHENSIS)
Savannah Sparrow (Passerculus sandwichensis) Science Article 1 abstract The orientation system of the Savannah sparrow (Passerculus sandwichensis) is typical of nocturnal migrant passerine birds. It is based on a system of interacting compass senses: magnetic, star, polarized light and, perhaps, sun compasses. The magnetic compass capability develops in birds that have never seen the sky, […]
Intraspecific Nest Parasitism in the Savannah Sparrow
Savannah Sparrow (Passerculus sandwichensis) Science Article 6 abstract Evidence of intraspecific nest parasitism in passetines is rare although some well documented cases do exist (Yom-Tov et al. 1974, Ibis 116: 87-90). This note describes an incident whose circumstances suggest that two complete clutches were laid simultaneously in the same nest by two female Savannah Sparrows […]
SEXUAL DIMORPiHSM AND POPUIATION SEX RATIOS IN JUVENILE SAVANNAH SPARROWS
Savannah Sparrow (Passerculus sandwichensis) Science Article 8 abstract Savannah Sparrows (Passerculus sandwichensis) breeding on Kent Island, New Brunswick, Canada, are polygynous and sexually dimorphic in size. The sex of 7-d-old nestlingscannot be reliably identified by size alone, but juveniles begin to display clear sexualdimorphism in size by the time they reach independence, several weeks after […]
FIFTY:FIFTY OFFSPRING SEX RATIOS IN SAVANNAH SPARROWS (PASSERCULUS SANDWICHENSIS)
Savannah Sparrow (Passerculus sandwichensis) Science Article 2 abstract Over a 14 year period, we determined offspring sex ratios in a population ofSavannah Sparrows (Passerculus sandwichensis) breeding on Kent Island, an isolated 80 ha islandin the Bay of Fundy, New Brunswick, Canada, based on morphological measurements of318 independent juveniles and 361 returning adults of known parentage. […]
Post-mortem digestion of stomach contents in the Savannah Sparrow
Savannah Sparrow (Passerculus sandwichensis) Science Article 7 abstract Van Koersveld (Proc. 10th Intern. Ornith. Congr.: 592-594,1 951) demonstrated that digestion in Corvidae continues for 20 to 30 minutes after death unless stopped in somemanner. He also demonstrated that soft-bodied forms such as earthworms were completely digested within that time and wireworm larvae were nearly gone […]