The biology of the Yellowthroated Sandgrouse Pterocles gutturalis in a South African agricultural landscape

Abstract

Tarboton, W.R., Blane, S. & Lloyd, P. 1999. The biology of the Yellowthroated Sandgrouse Pterocles gutturalis in a South African agricultural landscape. Ostrich 70 (3&4): 214–219.

A local population of Yellowthroated Sandgrouse was monitored from 1988–1992 at Northam, Northern Province, South Africa, a region in which this species was previously an irruptive, non-breeding visitor. Yellowthroated Sandgrouse were found to be year-round residents, foraging and nesting exclusively in areas cleared for agriculture, particularly one-year fallow lands. They ate the dry seeds of a variety of weedy plants, especially Amaranthus and Crotalaria spp. Males outnumbered females 1.35:1. Egg-laying occurred from April-October, with a peak in June. Clutch size (2–3) averaged 2.85 (n=26), and the incubation period for one nest was 26 days after clutch completion. Nesting success was estimated at 24.8% (n=19 nests, 176 nest days), and the daily nest predation rate at 2.55%; predation and ploughing accounted for most nest losses. Average annual productivity was estimated to be within the range 0.42–0.85 young/pair/year. We suggest that the Yellowthroated Sandgrouse depends on the seeds of early successional plants for food and that the recent agricultural development of the region maintains sufficient areas of fallow land to allow this otherwise nomadic species to become a breeding resident.