Adaptational Biology and Energy Relationships of the Collared Peccary (Tayassu Tajacu)

Abstract

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Implications of climatic seasonality on activity patterns and resource use by sympatric peccaries in northern Pantanal

“…Life in arid and semiarid environments is a challenge to mammals because of the wide temperature ranges and associated water shortages. The collared peccary (17-35 kg) and the white-lipped peccary (25-40 kg) do not display the behavioral strategies commonly used by mammals to address these challenges in arid environments, such as digging holes and burying themselves, and/or tolerate direct sun exposure for prolonged periods because of their low thermal inertia (property associated with the body size) (Cain et al 2006;Zervanos and Hadley 1973). For these reasons, the collared peccary has been considered a model organism to study physiological and behavioral adaptations in arid environments over the past four decades (Gabor et al 1997;Sowls 1997;Zervanos 1975;Zervanos and Day 1977;Zervanos and Hadley 1973).…”

“…Collared peccaries have many physiological characteristics that prevent dehydration, such as their ability to reduce water loss through evaporation and urination, and are capable of doubling their urine osmotic concentration (Zervanos and Hadley 1973). Studies using metabolic chambers demonstrated that this species has a narrow thermoneutral zone (TNZ, temperature range over which the animals maintain their basal metabolic rate without causing additional water loss) that ranges from 25°C (lower critical temperature) to 35°C (upper critical temperature).…”

“…Laboratory and field observations have shown that collared peccaries significantly increase their heart and respiratory rates at high temperatures, which may lead to high water loss rates (up to 49 ml/h). Despite possessing sweat glands, collared peccaries pant as their main means of evaporative cooling (Zervanos 1975;Zervanos and Hadley 1973). Panting instead of sweating enables an organism to raise its body and skin temperatures above the air temperature.…”

“…Panting instead of sweating enables an organism to raise its body and skin temperatures above the air temperature. Thus, a thermal gradient from the animal to the environment is established, and extra heat gain is avoided (Oke 1978;Zervanos and Hadley 1973). The considerable physiologic knowledge available for collared peccaries contrasts with the scant information available for white-lipped peccaries, which also live in environments with climatic seasonality and wide daily temperature variation.…”

Thermal effects on movement patterns of yellow baboons

“…Despite growing theoretical interest, few ecological studies have addressed behavioral thermoregulation in mammals (RusSELL, 1971;ZERVANOS & HADLEY, 1973;MORHARDT & GATES, 1974;INGRAM & LEGGE, 1971). Nevertheless, biophysical models (PORTER et al, 1973;PORTER & JAMES, 1979;BAKKEN, 1976;GATES, 1980;PORTER & TRACY, 1983) clearly demonstrate that small-scale microhabitat differences can significantly alter heat exchange and consequent metabolic energy costs.…”