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In this study, I describe the seasonality of reproduction in bottlenose dolphins by examining data from stranded animals, photographic surveys and focal follows. I examined inter-birth intervals from focal follows of known female dolphins. I found bottlenose dolphins that frequent the coastal waters of North Carolina to be comprised of at least two populations; one with a primarily spring birthing peak and a presumed second (or second and third) with two smaller birthing peaks in the fall and winter. These animals are reproducing at 2-3 year inter-birth intervals, which are shorter than bottlenose dolphin inter-birth intervals in the Moray Firth, Scotland, Shark Bay, Australia, or Sarasota Bay, FL. A decrease in reproductive intervals can indicate a density-dependent response to an anthropogenic disturbance or a natural change. Association patterns between and among these known females revealed relationships that have persisted for more than a decade. Most association patterns of the female dolphins in this area are long-term casual acquaintances which are evident in the fission-fusion grouping pattern, and individuals are not highly gregarious. Females appear to associate with most other females in the local area and do not form bands, as defined by researchers in Sarasota, FL (Wells et al. 1987). However, females do exhibit preferred associates, with whom they associate, regardless of reproductive state. Associations of females with young of the year were slightly stronger than associations between females with different aged calves, except for preferred associates. Future work will include genetic research on some of these known females, and continued study of the life and reproductive histories of these known females and their offspring. / Dissertation

In the summer, five creeks on the Fort Apache Indian Reservation were examined. Apache trout generally selected the deepest pools with the greatest amounts of instream cover and bankcuts. Though fish in three creeks may be Apache trout x rainbow trout hybrids, they were found to occupy the same type of pools. Regression models on environmental conditions in two creeks accounted for 83% and 76% of the variability in biomass of Apache trout. There was adequate nursery habitat (and successful reproduction) on two creeks, but such habitat was lacking in the other three creeks, and no evidence of successful reproduction was found. There was little evidence of survival of smaller Apache trout in areas of co-occurrence with non-native trouts but there was evidence of their survival upstream where fewer numbers of non-natives occur. The exclusion of smaller Apache trout may be from elimination or emigration. Greater populations of Apache trout may be supported through eradication of non-native trouts, the addition of instream cover, and structures designed to create longer lasting pools and bankcuts.

Bluehead sucker (Catostomus discobolus) and speckled dace (Rhinichthys osculus) were the only native species in Shinumo Creek above a waterfall located about 120 m upstream from the confluence of Shinumo Creek and the Colorado River. Rainbow trout (Oncorhynchus mykiss) was the only introduced species found upstream of the waterfall. I attribute the coexistence of the native and introduced species is attributed to differential use in resources and the similarly small size of bluehead sucker and rainbow trout. Mean total length of bluehead suckers was 160 mm and the largest fish captured was 230 mm (n = 77). Mean length of rainbow trout was 149 mm (maximum = 300 mm; n = 46). Bluehead suckers in Shinumo Creek were smaller than individuals observed in the mainstem Colorado River. Small size may be a response to the decreased size of the habitat available. The permanence of the waterfall barrier near the mouth of Shinumo Creek is a result of regulation of the Colorado River that prevents inundation of the waterfall.

Five species of waterbirds were collected from five sites on Imperial National Wildlife Refuge between April and August of 1993. There were previous baseline contaminants data for all sites. Sites were of two distinct habitat types. Backwater lakes have a direct connection to the mainstem of the Colorado River, and seep lakes receive river water only via seepage through the soil column. Selenium concentrations in liver, kidney, and muscle tissues were consistently higher in birds collected from backwater lakes than those collected from seep lakes. Eighty-one percent of the birds collected on backwater lakes (n = 52) were above the effect threshold for reproductive impairment or embryotoxicity (10 ppm dry weight in livers). Herbivorous birds had significantly (p ≤ 0.05) lower tissue selenium levels than those species feeding on animal matter. Of the birds feeding on fish and invertebrates, 83% (n = 47) had selenium levels in liver above the effect threshold. Differences in selenium concentrations based on diet suggest food chain cycling of selenium. Eggs from waterbirds as well as those from neotropical migrants were above the 3 ppm embryotoxicity threshold.

I compared vegetation features and rodent communities between manipulated and non-manipulated ranges in southeastern Arizona during summers 1996 and 1997. I also examined the effect of burying traps to determine if this procedure altered trap sensitivity. I used two-way analysis of variance or paired t-tests for all comparisons and identified relationships between rodents and vegetation features with linear regression. There was no difference (P ) in rodent species richness or population size between mechanically treated and reference areas. Rodent species richness and population size were greater on ungrazed compared to grazed areas (P ), but there was no difference in rodent diversity (P = 0.13). Prescribed fire did not have an obvious impact on rodent species richness or population size, though there seemed to be an increase in kangaroo rats following the burn. Buried traps may have demonstrated a reduction in sensitivity because I caught fewer animals in those traps compared to non-buried traps (P = 0.087).

Uma notata in the Mohawk Dunes had population densities in good habitat of 15-17 lizards/ha. Testis volumes peaked in April-May and declined to low levels by August. Egg production peaked in May during 1995 but did not occur in spring 1996. Minimum convex polygon home range estimates were 530 (±70 SE) m² for 2 adult males and 228 (±82) m² for 8 adult females. Adjusted for sample size bias, these estimates were 994 (±422) and 774 (±302) m², respectively. Subadults had smaller home ranges. Uma notata actively used perennial plants as escape cover, preferentially selecting Ambrosia dumosa. I found significant use of plant materials in Uma notata diet with both ontogenetic and seasonal shifts in proportions of plant items. Their diet included 65 taxa of arthropods from 39 families, along with 13 plant species in 7 families. I also studied survival rates, tail loss, substrate selection, and thermal effects.

Thesis advisor: Eric Strauss / Thesis advisor: Peter Auger / Northern Diamondback Terrapin (Malaclemys terrapin terrapin) hatchlings from the Great Marsh of Barnstable, Massachusetts on Cape Cod were studied as part of a headstarting program at Boston College. Although headstarting programs are relatively common methods to revive wild turtle populations, concern exists over the ability of headstarted terrapins to exhibit normal behavior when released into the wild. Observations of terrapins in the wild and in the laboratory suggest that terrapins are highly social and that these social interactions are modulated by kinship relations. This study investigated the social behavior of juvenile terrapins while they were basking on a restricted site. Groups of familiar kin and nonkin, and unfamiliar kin and nonkin were tested. Familiar kin were found to bask in larger groups and showed a willingness to share the limited basking site. Unfamiliar nonkin also interacted, but were more aggressive. Unfamiliar kin and familiar nonkin were not distinguishable in their behaviors. These results suggest that terrapins form social groups based on both familiarity and relatedness. Learning how captive headstarted terrapins form social groups and share resources may provide key information for their survival and recovery efforts in Massachusetts. / Thesis (BS) — Boston College, 2007. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Biology. / Discipline: College Honors Program.

Thesis advisor: David Krauss / Behavior in a confined group of mandrills (Mandrillus sphinx) and a confined group of ring tailed lemurs (Lemur catta) were analyzed to reveal any significant differences in agonistic behaviors and to assess the varying stress levels between individuals. I predicted that the activity rate of the individuals would determine the amount of agonistic behavior demonstrated, specifically that more active individuals would be more frequently performing agonistic behaviors than those who were less active. The mandrills as a whole exhibited a higher activity rate than the lemurs, and the proportion of time spent exhibiting agonistic behaviors was also higher, as expected. These results suggest that the mandrill population is under more stress than the lemurs. Differences in the age makeup of these groups may partially explain the behavioral differences that occurred: the mandrills' group included a juvenile who was considerably more active than his parents while all three lemurs observed were adults. Differences in the size of the exhibit may also explain the differences as the exhibit for the mandrills was smaller than that of the lemurs, while the mandrills were more than triple the lemurs' size. This analysis supports earlier studies: that primate behavior is influenced strongly by their environment and its cohabitants. / Thesis (BS) — Boston College, 2004. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Biology. / Discipline: College Honors Program.

This study focuses on two key questions in limb development: limb patterning and directional limb outgrowth. In the first part of this work, I studied the role of Msx2 gene in limb patterning. Msx2 cDNA was transferred into a mouse posterior limb bud (MPLB) cell line, MPLB2.1, which maintains ZPA signaling. Msx2 is shown to be able to increase the frequency and to improve the quality of supernumerary digit formation, probably by influencing the pre-existing ZPA signal in MPLB2.1 cells. Msx2 alters the surface properties of the cells, and Msx2-expressing MPLB-2.1 cells acquire an ability to recognize each other and to aggregate, suggesting that Msx2 might affect ZPA signaling via influencing cell-cell interaction. In the second part of this work, I studied the effects of the AER, FGF-2 and FGF-4 on the expression of Sonic hedeghog (Shh). FGF-2 and FGF-4 can maintain Shh expression after the AER removal. FGF-2 and FGF-4 also regulate the spatial expression of Shh domain in the presence of the AER. The alteration of Shh domain by FGFs is found to be due to the movements of Shh-expressing cells. Furthermore, FGF-2 and FGF-4 cause the reduction of the length of limb skeletal elements. FGF-2 also causes the loss of the digits. These results suggest that cell movements are important for normal limb formation. To further characterize how FGFs influence cell movements, limb bud cells are labeled with DiI. FGF-4 is shown to stimulate posterior cells within Shh domain to migrate, while FGF-2 does not induce a migratory response in a similar assay. In addition, anterior cells only weakly respond to FGF-4-stimulated cell migration. On the other hand, the AER can stimulate cells to migrate distally and FGF-4 can replace the AER in stimulating cell migration. Prevention of normal distalward cell migration causes the reduction of length of limb skeletal elements, indicating that cell migration stimulated by FGF-4 is involved in normal limb development. Taken together, I provided the first evidence showing the in vivo limb cell migration stimulated by FGF-4. I propose that both cell migration and cell proliferation are required for normal limb formation / acase@tulane.edu