Passerculus sandwichensis: BirdLife International

Author(s):  
The Condor ◽  
2005 ◽  
Vol 107 (1) ◽  
pp. 21-28 ◽  
Author(s):  
Robert M. Zink ◽  
James D. Rising ◽  
Steve Mockford ◽  
Andrew G. Horn ◽  
Jonathan M. Wright ◽  
...  

Abstract We compared sequences from two mitochondrial DNA (mtDNA) genes (ND2, ND3) in Savannah Sparrows (Passerculus sandwichensis; n = 112) sampled from Baja California (five sites), coastal Sonora and the continental range (eight sites). Populations from Baja California, San Diego and Sonora formed a clade within which there was no phylogeographic structure; this clade merits species status (Passerculus rostratus). The other clade, consisting of phenotypically “typical” savannah sparrows, should be classified as P. sandwichensis. Among the typical sparrows, there was no phylogeographic structure, although two major clades were discovered. Representatives of each of the two main clades occurred at most sampling localities, excluding Suisan Bay, California and Sable Island, Nova Scotia, Canada. Haplotypes found on Sable Island, representing the “Ipswich Sparrow,” were not distinctive, thereby failing to support species status for this taxon. On Isla San Benito, a single haplotype was found, which also occurred in other Mexican localities. The results for Sable Island and Isla San Benito show that size and plumage coloration can evolve rapidly. Variación en ADN Mitocondrial, Límites entre Especies y Evolución Rápida de la Coloración del Plumaje y el Tamaño en Passerculus sandwichensis Resumen. En este estudio comparamos secuencias de dos genes mitocondriales (ND2 y ND3) entre individuos de la especie Passerculus sandwichensis (n = 112) muestreados en Baja California (5 sitios), la costa de Sonora y el rango de distribución continental (8 sitios). Las poblaciones de Baja California, San Diego y Sonora formaron un clado, al interior del cual no existió estructura filogeográfica; este clado merece estatus de especie (Passerculus rostratus). El otro clado, conformado por individuos fenotípicamente “típicos”, debe clasificarse como P. sandwichensis. Entre los individuos típicos no existió estructura filogeográfica, aunque se descubrieron dos clados principales. Individuos representativos de cada uno de estos dos clados se encontraron en la mayoría de las localidades, excepto Suisan Bay, California y Sable Island, Nova Scotia. Los haplotipos encontrados en Sable Island, correspondientes al “gorrión de Ipswich” no fueron distintivos, lo que no apoya el estatus de especie para este taxón. En Isla San Benito se encontró un solo halpotipo, el cual también se encontraba en otras localidades mexicanas. Los resultados de Sable Island e Isla San Benito muestran que el tamaño y la coloración del plumaje pueden evolucionar rápidamente.


1973 ◽  
Vol 51 (7) ◽  
pp. 697-713 ◽  
Author(s):  
R. A. Owens ◽  
M. T. Myres

The effects of several forms of agricultural use of native fescue (Festuca scabrella) grasslands upon populations of native passerine birds were studied in the Hand Hills of southern Alberta in 1970.Censuses of avian populations were carried out on twelve 40-acre (16.2 ha) study plots as well as on two 10-mi (16.1 km) long roadside routes. The vegetation on the study plots and along the roadside routes was described.Native fescue grasslands, undisturbed for 3 years, supported a passerine community consisting of Baird's sparrow (Ammodramus bairdii), Sprague's pipit (Anthus spragueii), savannah sparrow (Passerculus sandwichensis), clay-colored sparrow (Spizella pallida), and western meadowlark (Sturnella neglecta). Incomplete disturbance of fescue grasslands, by mowing for hay or grazing by cattle, reduced or eliminated Baird's sparrow and Sprague's pipit but permitted the ingress of horned lark (Eremophila alpestris) and chestnut-collared longspur (Calcarius ornatus). Total elimination of the native grassland, by ploughing and cultivation for cereal crops, eliminated all passerine species except the horned lark. Peripheral disturbed areas resulting from cultivation, such as held boundaries and roadside ditches, may have benefited several species that tend to occur in ecotonal habitats: savannah sparrow, clay-colored sparrow, and vesper sparrow (Pooecetes gramineus).


The Auk ◽  
1987 ◽  
Vol 104 (2) ◽  
pp. 277-289 ◽  
Author(s):  
Joseph B. Williams

Abstract I applied the doubly labeled water (DLW) technique to measure rates of water flux and energy expenditure of Savannah Sparrows (Passerculus sandwichensis) during two breeding seasons on Kent Island, New Brunswick, Canada. Simultaneous to DLW measurements, I constructed time-activity budgets for territorial males, monitored nest attentiveness for incubating females, and quantified frequency of nest visitation for parents feeding young. To ascertain the relationship between brood size and adult energy expenditure, I measured the energy expenditure of adults feeding 2, 4, and 6 nestlings. There was little difference in field metabolic rates (FMR) between territorial males [161.0\pm 21.7 (SD) ml CO2/h). and males that fed 4 nestlings (157.6 ± 19.7 ml CO2/h). Incubating females expired CO2 at rates lower than males during the same time period (134.4 ± 7.9 vs. $161.0 ± 21.7 ml CO2/h but similar to rates for females feeding 4 young, the normal brood size ($134.4 ± 7.9 ml CO2/h for incubating females vs. $136.5 ± 26.9 ml CO2h for females feeding young). Incubating females expended energy at a lower rate than females making 8 or more trips to the nest per hour, the average feeding rate for females late in the nestling period. For males and females together, water influx and efflux rates averaged 17.1 ± 3.2 and 17.2 ± 3.0 ml H20/day, suggesting that birds balanced water intake against water losses. Mean daily solar radiation (MDSR; W/ m2) also influenced FMR during the nestling period. The equation ml CO2/h=172.6-0.07 (MDSR) described the relationship. When brood sizes were manipulated, parents responded by altering their frequency of nest visitation; as frequency increased, so did the FMR of females but not of males. The equation ml CO2/h =98.4 + 5.3 (mean visits/h) described the relationship. Construction of a food budget indicated that, on average, territorial males consumed 21.1 g fresh arthropods per day, while incubating females ingested 17.5 g/day or 210.0 g during the 12-day incubation period. Through the 8-day nestling period, males augmented their foraging by 75%, females by 87%, to feed a brood of 4.


1984 ◽  
Vol 62 (1) ◽  
pp. 23-27 ◽  
Author(s):  
Marie Meunier ◽  
Jean Bédard

The diet of savannah sparrow (Passerculus sandwichensis) nestlings was monitored at Îsle Verte, Québec, during the 1980 breeding season. Adults carried exclusively arthropods to the nest. The main prey types found were Lepidoptera and Hymenoptera larvae, larval and adult Diptera and Homoptera. The proportion of different prey types in the diet varied during the season but there was no close relationship between temporal changes in the indices of prey abundance in the habitat and the type of prey chosen by the adult birds. Both the type and size of prey brought to the nest changed with the age and number of nestlings (aged 4–10 days). The proportion of Homoptera in the diet decreased sharply with age while that of Lepidoptera and Diptera increased. Adults feeding broods of four brought a larger proportion of large prey items (Lepidoptera and Hymenoptera larvae) than those feeding broods of a lesser size; to these they brought a larger proportion of smaller items such as Diptera and adult Lepidoptera. Males and females brought the same major prey types to the nest but not in the same proportions.


1997 ◽  
Vol 75 (4) ◽  
pp. 641-644 ◽  
Author(s):  
Clinton K. Miller ◽  
Jeanne M. Fair

We investigated the effect of blow fly larvae (Protocalliphora spatulata) on nestling savannah sparrows (Passerculus sandwichensis) in Alaska subject to biennially fluctuating prey abundance. Grasshopper populations in some regions of interior Alaska can show a strong biennial periodicity. Growth of nestling savannah sparrows, numbers of blow fly larvae in nests and on nestlings, and grasshopper populations were monitored during four breeding seasons (1990–1993) on the Delta Agriculture Project site near Delta Junction, Alaska. Growth parameters for parasitized and nonparasitized nestlings were compared within and between years. There were no significant differences in growth parameters between parasitized and nonparasitized nestlings between any years. There were also no differences in growth parameters within years, except for tarsus length in 1991 and nestling mass in 1993 (low grasshopper years); in 1993, parasitized nestlings were heavier and the sample size was small. Additionally, there were no differences in fledging success within years. Although parasitism combined with other factors (e.g., food limitation) may have an impact on avian reproduction, our data do not support this.


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