Category: Emberizidae

Northwestern song sparrow populations show geneticeffects of sequential colonization

Song Sparrow (Melospiza melodia) Science Article 15 abstract Two genetic consequences are often considered evidence of a founder effect: substantialloss in genetic diversity and rapid divergence between source and founder populations.Single-step founder events have been studied for these effects CHRISTIN L. PRUETT and KEVIN WINKER, Molecular Ecology (2005) 14 , 1421-1434 Download article download full […]

Song repertoire size varies with HVC volume and is indicative of male quality in songsparrows (Melospiza melodia)

Song Sparrow (Melospiza melodia) Science Article 9 abstract Complex birdsong is a classic example of a sexually selected ornamental trait. In many species, femalesprefer males with large song repertoires, possibly because repertoire size is limited by the size of songcontrol nuclei which reflect developmental success Jeremy A. Pfaff et al, Proc. R. Soc. B (2007) […]

Fitness Correlates of Song Repertoire Size in Free-LivingSong Sparrows (Melospiza melodia)

Song Sparrow (Melospiza melodia) Science Article 8 abstract Models of sexual selection propose that exaggerated secondarysexual ornaments indicate a male’s own fitness and the fitnessof his offspring. These hypotheses have rarely been thoroughly testedin free-living individuals because overall fitness Jane M. Reid et al, Am. Nat. 2005. Vol. 165, 2005 Download article download full text […]

Effects of early nutrition on growth rate and adult size in songsparrows Melospiza melodia

Song Sparrow (Melospiza melodia) Science Article 4 abstract We manipulated the quantity of food provided to hand-reared song sparrows Melospizamelodia from 3 to 18 days post-hatching, a period when young birds in the wild areespecially likely to experience nutritional stress. A control group was given unlimitedfood, while an experimental group was limited to 60% of […]

Proficient incubation by inexperienced SavannahSparrows Passerculus sandwichensis

Savannah Sparrow (Passerculus sandwichensis) Science Article 3 abstract We compared the incubation behaviour of 1-year-old female Savannah Sparrows Passerculussandwichensis nesting for the first time with that of older females that had nested in previousyears on Kent Island, New Brunswick, Canada. Using temperature probes inserted into 32nests, we determined the length and variability of incubation shifts […]

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 […]

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. […]