Life history of the desert iguana, Dipsosaurus dorsalis
Herpetologica
1984
Journal Article
40
4
415-424
Dipsosaurus dorsalis
A population study of marked Dipsosaurus dorsalis was conducted at Thousand Palms, California. Growth of hatchlings and some yearlings occurred at a mean rate of over 22 mm/yr in snout-vent length. Growth during high rainfall years was twice that during low rainfall years. Reproductive size was attained by 82% of the 1979 cohort at 31-33 mo of age. Recapture data showed that D. dorsalis remain close to their hatching sites, suggesting little or no emigration or immigration. Survivorship was high in all age classes. Average annual survivorship was 73% for hatchlings, 43% for yearlings, 46% for two year olds, and 60% for adults. There were no significant differences in annual survivorship of subadult and adult desert iguanas. Mean annual survivorship of adult males (57%) and females (66%) also was not significantly different. Two D. dorsalis in this study lived at least 7.5 yr. Spring density estimates (excluding hatchlings) were 332/ha and 425/ ha. Life history traits of this population of D. dorsalis appear to fit most closely those for organisms termed K-selected and constitute a reproductive strategy best characterized as late-maturing, single brooded.