Year: 1979
Type: article
Abstract: Variation in growth rates of young within populations of birds has been related to season, brood size, hatching order, habitat, and geographical locality (for reviews, see Lack, 1966;Ricklefs, 1968;Klomp, 1970).In addition, growth has been interpreted as an index to ecological conditions, especially the availability of food (Gibb, 1950; Balen, 1973) and to interactions among siblings (cf., Parsons, 1975; Howe, 1976;Bryant, 1978; O'Connor, 1978a,b).By comparing variation within broods and between broods, one may investigate growth rate as an expression of the ability of parents to care for their broods and of genetic and maternal components of quality of the young.In this paper, we summarize a four-year study of intraspecific variation in growth rate and final weight achieved by nestling European Starlings (Sturnus vulgaris) in southeastern Pennsylvania.Our primary purpose here is to describe patterns of variation in growth, rather than to speculate on their causes. MATERIALS AND METHODSNest boxes were set out on property adjacent to the Stroud Water Research Laboratory near London Grove (Avondale), Pennsylvania, approximately 30 mi ESE of Philadelphia.Boxes were placed in old-fields bordered by hedgerows and, on some sides, by upland deciduous forest.A small stream runs through the study area.Local land use has created a mosaic of woodlots, pastures, and cultivated crops, primarily corn.In 1970, 28 nest boxes were placed on steel poles, between 1.8 and 2.0 m off the ground, a minimum of 10 m apart in two adjacent fields.We recorded weights and measurements of all nestlings in all broods in 1970, 1971, and 1972, and in first broods in 1973.The inside dimensions of the nest boxes were 15 x 15 x 30 cm.Removable fiat tops overhung the front of the boxes by 5 cm.A 4.4-cm entrance hole was centered 5 cm below the top of each box.The boxes were constructed of 2-cm thick pine and painted dark brown.They were cleaned out and repaired after the end of each breeding season.Boxes were checked each day during the breeding season.Most visits to the nests were made after 1200 during the period of egg laying and between 0800 and 1200 thereafter.In 1970 and 1971, nestlings were identified individually by colored threads tied around one leg at 2 or 3 days of age.In 1972 and 1973, nestlings were given distinctive tattoos of India ink on their abdomens (Ricklefs, 1973).In all four years, young were given colored, plastic leg bands when 7 to 9 days old and aluminum Fish and Wildlife Service bands before fiedging.Nestlings were weighed daily, using an Ohaus triple-beam balance (scale to 0.1 g) in 1970 and Bird-Banding, Autumn 1979, 50(4): 338-348 INTRASPECIFIC VARIATION IN THE GROWTH RATE OF NESTLING EUROPEAN STARLINGS
Source: Bird-Banding
DOI: 10.2307/4512485
Authors: Robert E. Ricklefs, Susan Peters
Language: English
Topic: Avian ecology and behavior
Subfield: Ecology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: green
Funder: National Science Foundation
OpenAlex ID: W2802913702