Effects of food supplementation on the physiological ecology of female Western diamond-backed rattlesnakes (Crotalus atrox)
- 30 March 2005
- journal article
- Published by Springer Science and Business Media LLC in Oecologia
- Vol. 144 (2), 206-213
- https://doi.org/10.1007/s00442-005-0056-x
Abstract
Food availability is an important factor in the life histories of organisms because it is often limiting and thus can affect growth, mass change, reproduction, and behaviors such as thermoregulation, locomotion, and mating. Experimental studies in natural settings allow researchers to examine the effects of food on these parameters while animals are free to behave naturally. The wide variation among organisms in energy demands and among environmental food resources suggest that responses to changes in food availability may vary among organisms. Since most supplemental feeding field experiments have been conducted on species with high energy demands, we conducted a supplemental feeding study on free-ranging, female Western diamond-backed rattlesnakes (Crotalus atrox), a species with low energy demands and infrequent reproductive investment. Snakes were offered thawed rodents 1–4 times per week. Over two active seasons, we collected data on surface activity, home range size, growth, mass change, and reproduction of supplementally fed and control snakes. Fed and control snakes did not differ in surface activity levels (proportion of time encountered above versus below ground) or home range size. Fed snakes grew and gained mass faster, and had a dramatically higher occurrence of reproduction than control snakes. Also, fed snakes were in better body condition following reproduction than snakes that were not fed. However, litter characteristics such as offspring number and size were not increased by feeding, suggesting that these characteristics may be fixed. These data experimentally demonstrate that food availability can directly impact some life history traits (i.e., growth and reproduction for C. atrox), but not others (i.e., surface activity and home range size for C. atrox). The relationship between food availability and life history traits is affected in a complex way by ecological traits and physiological constraints, and thus interspecific variation in this relationship is likely to be high.Keywords
This publication has 34 references indexed in Scilit:
- Comparative demography of black rat snakes ( Elaphe obsoleta ) in Ontario and MarylandJournal of Zoology, 2002
- Plastic vipers: influence of food intake on the size and shape of Gaboon vipers (Bitis gabonica)Journal of Zoology, 2001
- An experimental test of the link between foraging, habitat selection and thermoregulation in black rat snakes Elaphe obsoleta obsoletaJournal of Animal Ecology, 2001
- Analysis of Animal Space Use and MovementsPublished by Elsevier BV ,2001
- Effects of winter food supplementation on reproduction, body mass, and numbers of small mammals in montane AustraliaCanadian Journal of Zoology, 2000
- THERMAL ECOLOGY AND SEXUAL SIZE DIMORPHISM IN NORTHERN WATER SNAKES,NERODIA SIPEDONEcological Monographs, 2000
- Variation in Clutch Size and Offspring Size Relative to Environmental Conditions in the Lizard Sceloporus virgatusJournal of Herpetology, 1999
- Variation in oxygen consumption of the western diamondback rattlesnake ( Crotalus atrox ): implications for sexual size dimorphismJournal of Comparative Physiology B, 1998
- Ontogenetic Variation in Growth and Sexual Size Dimorphism in a Central Arizona Population of the Western Diamondback Rattlesnake (Crotalus atrox)Ichthyology & Herpetology, 1998
- Ecology and Energetics of Three Sympatric Rattlesnake Species in the Sonoran DesertJournal of Herpetology, 1995