Avian adaptations to the Kalahari environment: A typical continental semidesert

Abstract

Bird species adapted to the Kalahari are generally either (a) sedentary, insectivorous (or carnivorous) and non-gregarious, or (b) nomadic, granivorous and gregarious even when breeding. Ground-dwelling birds predominate numerically and are cryptically coloured to avoid predation. Many species have nasal glands which secrete hypertonic solutions in response to the intake of fluids with high solute concentrations, as an adaptation to water conservation. Thermoregulation is discussed especially in relation to high ambient temperatures. Breeding is initiated in most species by rainfall or associated ecological effects, correlated with improved body condition of the females; lag periods between rain and egglaying are related to diet and time of year. Nest orientation is also related to season and capitalizes on maximal shade in summer. Parental care in sandgrouse is discussed.