in the tagged dolphin temporarily leaving the dolphins with which it was 

 encountered. Other dolphins {e.g., FB514, FB521, FB522) were not evasive, 

 however, euid allowed the boat to approach them. Dolphins had become 

 much less evasive by week 3. However FB501 and FB518 appeared to be 

 somewhat shy of the vessel throughout their tag attachment time (59 and 61 

 days, respectively). Most non-radio-tagged, freeze-branded dolphins did not 

 display such consistent evasiveness when encountered, nor did unhandled 

 dolphins. This wariness may have been a response to the tag, but there are 

 few pre-tagging behavioral observations against which to compare. FB501 and 

 FB518 were not noted to be especially evasive in post radio- tracking sightings. 

 Of five group sightings of to-be-radio-tagged dolphins in May 1992, only one 

 group was noted to be evasive of the vessel. In this case, evasiveness was 

 probably attributable to the group's initial behavior. This group, containing 

 FB504, was exhibiting "rest" and /or "slow travel". The other four such groups 

 were "traveling" or "feeding". 



All 10 radio-tagged dolphins were morutored in the months after the 

 radio tracking and have been seen without the packages. Damage to the dorsal 

 fin varied from small circular scars, to pierced fins, to significant new notches 

 in the trailing edge, p)erhaps caused by earlier release of the anterior bolt and 

 subsequent hydrodynamic drag of the radio package. 



In addition to the intensive field effort between 6 July and 30 August 1992, 

 eight other photographic surveys were conducted between 14 May 1992 and 18 

 June 1993. In total, 136.3 hr were spent on the water, 2,236 dolphins in 648 

 groups v\rith a mean group size of 3.5 ± 2.86 (SD) dolphii\s were seen, and 4,572 

 photos were taken (Table 2). Among non-calves, females and males did not 

 differ in number of sightings (^test), nor was number of sightings linearly 

 dependent on age (regression). After 12-14 months, freeze-brands became 

 difficult to read on most adult dolphins; the calf freeze-brands became 

 unreadable 3-4 months earlier. 



Many freeze-branded dolphins were resighted (Fig. 5). Six adults and one 

 calf whicii were later freeze-branded were identified during the initial survey 

 in May 1992. Because of the incomplete and sporadic nature of only several 

 days erf visual surveys during each trip, and the geographically unbalanced 

 survey effort (Fig. 4), absence of identified animals in the photo-record is not 

 proof of their absence from the area. On the contrary, the evidence from 

 resightings indicates a high degree of interseasonal site fidelity. One set of 

 animals stands out (Fig. 5, FB523-FB532, five males and five females). None 

 of them were resighted in the year since they were captured and freeze- 

 branded in July 1992. All were captured at the extreme northeast end of the 

 study area, 5.5-20 km northeast of the Matagorda Ship Channel Jetties on 

 Matagorda Peninsula (Appendix 30- Surveys in the year follovdng the 



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