More Reptile Reading: Demuth JP, 2001. Wild tortoises generally live for 40—60 years and become reproductively active at 10—20 years of age Epperson and Heise 2003 ; Mushinsky et al. The gopher tortoise Gopherus polyphemus is one of four native North American tortoise species generally occupying dry, sandy habitats of the southern United States and northern Mexico.
Even males that are generally successful in aggressive encounters, therefore, may be temporally limited in the number of females with which they can mate. Moon, Earl D.
Unless already identified, all individuals were numbered and uniquely marked by notching the marginal scutes, and all individuals were released at the site of capture. Although they are typically thought of as woodland turtles, our studies of movement patterns of radiotelemetered individuals at Woodruff show that some individuals spend weeks at a time in the middle of marsh habitat.
Not all burrows are active. Thus, it is likely that the greater proportion of fertilization attributable to larger males is at least partially a result of winning aggressive encounters and gaining greater access to females.
When intact, they look like miniature ping-pong balls. Male-male confrontations, in which the participants attempt to overturn one another, also are observed during courting season Hailman 1991 ; personal observation. Download all figures. On the refuge, dozens of burrows can be found by simply looking along the railroad track embankment south of the refuge entrance.
Field observation can identify dominant males on an incident-by-incident basis, but rarely can they reveal whether dominance leads to greater reproductive success. Earliest Reptile Footprints The earliest evidence for the existence of reptiles has been found in Canada. Adult size also may be a significant factor regulating multiple paternity.
Table 1. Male 43 also was the sole putative sire for one of the single-sire clutches Table 3. Most Popular. If among all hatchlings, more than two paternal alleles were found at any locus, the clutch was classified as having multiple sires.
Although believed to be previously abundant, the gopher tortoise is declining in numbers, mostly due historically to harvesting and recently to extensive habitat loss Auffenberg and Franz 1982 ; Diemer 1986.
The female digs a nest at the mouth of her burrow or another sunny site where she buries ping-pong-ball-sized eggs that hatch about 3 months later. Does multiple paternity occur in gopher tortoise clutches, and, if so, is the fertilization of a single clutch evenly divided among the males?
Differences between various groupings of individuals were tested using Student's t tests. They lack the stripes down the back, and have a smaller plastron, if you are lucky enough to have one in hand.
A third possibility is that the female may be a recent immigrant into the area. Smaller and lighter females are likely also to represent younger and less experienced females.
Instances of male courtship behaviors e. Further studies using other populations and more individuals per population are necessary to fully characterize the consequences of the promiscuous mating system in gopher tortoises.