Behavioral states which involved more thar\ a single behavior were 

 scored for each behavioral component. Behavioral categories and dolphin 

 group sizes were examined for variation across each other, survey month, 

 hour of day (0800-1959), and habitat type ("channel": water bodies such as the 

 ICW, Big Bayou, and Saluria Bayou; "jetty": between or within 50 m of either 

 the ICW at Port O'Connor jetties or the Matagorda Ship Channel jetties; 

 "bay": all other bay waters; and "offshore": gulf waters). For groups containing 

 freeze-branded dolphins, further analyses were made for differences by sex, 

 age class, females vsdth- and without-calf, and pregnant and non-pregnant 

 females. Groups containing more than one category of individual {e.g., males 

 and females) were scored for each category. Travel directions, in degrees 

 magnetic, were converted to x-y coordinate vectors and analyzed for 

 differences between survey month (Watson and Williams test, Batschelet 

 1972:85). The numbers of neonates seen were examined for seasonal trends. 



Differences in geographic distribution were examined by plotting sighting 

 locations for males vs. females; group size classes of < three, four-six, 

 and ^ seven dolphins; pregnant vs. non-pregnant females; females with-calf 

 vs. vsrithout-calf; neonates; behavior (socializing^ traveling, feeding); and age 

 class. 



Estimates of population size were made with Bailey's modification of the 

 Petersen Estimator. The Petersen Estimator is a ratio which states that the 

 number of marked animals recaptured in a sample is proportional to the total 

 number of marked animals in the total population (Blower et al. 1981). 

 Bailey's modification is an adjustment for recapture v^dth replacement 

 (Eberhardt et al. 1979, Hammond 1986): 



Petersen Estimator Bailey Modification 



N = J^ ^^M(n + 1) 



where 



(min) m + 1 



^ = the total papulation size, 



1 = the number of animals sampled, 



M = the total number of marked animals at large, and 



^ = the number of marked animals recaptured (including 

 resightings of the same individual). 



8 



