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The Spotted Salamander (Ambystoma maculatum) is widespread throughout the eastern United States and southern Canada. In 1997, we initiated a long-term study of A. maculatum at a breeding pond in Calhoun County, Alabama. Each winter, we captured salamanders as they returned to breed and inserted passive integrated transponders to permit positive identification of recaptures. We fit the von Bertalanffy growth-interval equation to data on snout-vent length taken from individuals captured and recaptured in different years and estimated intrinsic growth rates for both males and females. Males displayed rapid juvenile growth, which slowed as they neared estimated maximum size. Females, however, displayed relatively constant growth until nearing their estimated maximum size. The intrinsic growth rate of females was lower than that estimated for males. We hypothesize that sex-specific growth patterns maximize reproductive efforts of A. maculatum.

The testicular cycle of Sceloporus undulatus from Alabama was examined and com- pared to populations from Missouri and other areas. In Alabama males, the height of the breeding season (spermiogenesis and spermiation) occurred from March to May, accompanied by a decline in testis mass. Spermatozoa were present in the epididymides until July. During June and July, testis mass was minimal. A new spermatogenic cycle had begun by August. Testicular recrudescence occurred in fall with concomitant increase in testis mass. Seminiferous tubules contained many spermatids with a few transforming spermatozoa by the time lizards entered brumation. The timing of testicular events differs between northern and southern populations, likely reflecting regional differences in seasonal temperature regimes. Specifically, a longer warm season in Alabama appar- ently permits males to begin spermiogenesis and spermiation earlier and to complete fall recru- descence later than S. undulatus from Missouri.

Seasonal movements and habitat preferences of adult alligators were studied in a north-central Florida lake from September 1976 until September 1977. Nine alligators (5 females, 4 males) were outfitted with radio transmitters and monitored on Newnan's Lake, Alachua County, Florida. Study animals were located 627 times via telemetric signals and visual observations. Female alligators were more sedentary than males during all four seasons (winter, spring, summer and fall). Greatest movements and largest seasonal ranges for both sexes occurred during the spring. Females showed no evident preference for either lake or swamp habitat during the spring, while males preferred the open lake. Reduction in activity ranges was noted during the summer for both sexes. Males preferred the open lake during the summer while females restricted themselves to the surrounding swamps. Preference for the swamp during the summer by females was believed to be due primarily to nest construction, egg laying, and attendance at nest sites. The American alligator (Alligator mississippiensis), is the only crocodilian found in the United States in large numbers. It is especially abundant in Florida and is important in that state for several reasons. Many other animals are dependent upon the presence of alligator holes during periods of drought, especially in the Everglades. From an aesthetic standpoint the alligator is an example of Florida's pristine wildlife. The alligator also shows promise of becoming an economic resource because of the value of its hide. Biologists in Louisiana have shown for several years that the alligator can be harvested on a sustained yield basis (Palmisano et al., 1973). Significant research completed within Florida is by Jones (1966)-capture and tagging techniques; Fogarty and Albury (1968)-food habits of immature alligators; Hines et al. (1968)-alligator research progress report; Fogarty (1974)-ecology of the Everglades alligator; Forrester and Sawyer (1974)-leech infestations of alligators; and Goodwin and Marion (1978)-nesting ecology of alligators. Most of this research deals with alligators in the Everglades region. In order to manage alligator populations in north-central Florida, knowledge of seasonal movement patterns and habitat preferences of adult alligators is needed. This study has been designed to obtain this information in a previously unstudied habitat and is the first major telemetric study of adult alligators in Florida. The alligator's habitat of dense swamplands, lakes, and marshes make it a difficult animal to observe in the wild. Radio telemetry was the technique chosen to locate marked individuals in this study. The capture-recapture method (Chabreck, 1965) was not used because radio telemetry was more effective in meeting study objectives.

Examination of female Sternotherus odoratus in central Alabama revealed that follicular enlargement begins soon after oviposition of the last clutch in July. Yolking of the ovarian follicles continued from August-December, until reaching a size not significantly different from spring preovulatory follicles. Ovulation of the first clutch occurred during late April, and eggs were found in the oviducts from May-July. Central Alabama females have at least 2 clutches per reproductive season, with many laying 3. Mean clutch size was 2.6 (range 1-6). Clutch size was positively correlated to body size, but there was no significant trend for larger females to produce larger oviducal eggs. Females first reached sexual maturity while in the 65-75 mm CL range. Estimated average annual reproductive potential of females laying a maximum of 3 clutches was 7.8 eggs per year.