Information on reactions of delphinids to biopsy sampling and healing of associated biopsy wounds is limited. Results presented here report on the behavioral responses of free-ranging bottlenose dolphins (Tursiops truncatus) to remote biopsy sampling procedures, and provide information on stages of surgical biopsy wound repair. Biopsy samples of free-ranging dolphins were collected between February–May 1992 in Galveston Bay, Texas, using a sterilized corer-tipped bolt, launched from a crossbow. A total of 8 direct ‘hits’ were documented, 4 hits (50%) in which a tissue sample was obtained, 2 hits (25%) from which no sample was retrieved, and 2 hits (25%) in which the bolt struck the water (within approximately 30–60 cm) prior to striking the animal (no samples). Behav- ioral reactions were similar for all eight dolphins directly struck by a bolt, and were best character- ized as startle responses. As part of a NMFS sponsored capture effort to assess a 1992 bottlenose dolphin die-off in Matagorda Bay, Texas, surgical biopsy samples were taken from 35 dolphins (Sweeney, 1992). Biopsies roughly 3–5 cm in diam- eter and 1 cm deep, were surgically removed. While surgical biopsy wounds were not identical to remote biopsy wounds, they were comparable. Sixteen of the 35 surgically biopsied individuals were photographically resighted between July 1992 and December 1993. Photographs of biopsies immedi- ately after completion of surgical procedures and up to 476 days post-biopsy were classified into four stages of healing. Epidermis appeared to have cov- ered wounds by 40–42 days post-biopsy, but in some cases possibly as early as 15–26 days. Repig- mentation of epidermal tissue varied between indi- vidual dolphins, but in no cases occurred prior to 61 days post-biopsy. No indication of infection or related pathologies were detected from any of the biopsy wounds monitored during this study. Find- ings reported here suggest that when adequate care and caution are used, biopsy sampling of bottlenose dolphins is not likely to produce long-term behavioral alterations or result in physiological complications during wound healing.

Weller, D. W., V. G. Cockcroft, B. Würsig, S. K. Lynn, and D. Fertl. 1997. Behavioral and wound healing responses of bottlenose dolphins to biopsy sampling. Aquatic Mammals 23(1): 49-58.

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Radio-tracking of 10 bottlenose dolphins (Tursiops truncatus), from 9 July 1992 to 13 September 1992, and photographic surveys of 35 freeze-branded dolphins, from May 1992 to June 1993, were conducted in the Matagorda Bay area of Texas, in response to a mass mortality event which occurred between Matagorda and Aransas Bays, Texas, during spring 1992. The primary goals of the study were to assess range size and site fidelity, as well as to initiate a long-term ecological study by collecting data on social and behavioral patterns.

The Matagorda Bay dolphin population was found to be numerically robust, occupying all regions of the bay surveyed. Mean range size, based on radio telemetry, was 140 km2 (SD = 90.7, n = 10 dolphins). Males and females had similar range sizes though males visited the extremities of their ranges more frequently or for longer periods. Several generalities were observed: (1) Dolphins were capable of, and often did, traverse their range in several hours. (2) Dolphins traveled widely on some days, perhaps crossing their own ranges, while on other days movement was very confined, within 1–2 km2. This did not appear to have a temporal or geographic pattern. (3) Dolphins tended to spend about 1–4 days in a particular portion of their range. (4) Movement tended to be more confined at night than during daytime. (5) Dolphins tended to visit the extremes of their ranges only in the daytime. The assertions of (4) and (5) may be biased as a result of less sampling effort at night, with fewer triangulations than during daytime and no visual sightings.

Most, if not all, of the 35 freeze-branded dolphins appeared to be resident to the Matagorda–Espiritu Santo Bay area with much fluidity of group membership. Overall mark/recapture population size estimates from photo-identification suggested that 218 ± 71.4 (95% CI) dolphins utilized an area of 312 km2 in Matagorda and Espiritu Santo Bays, similar to an estimate made in 1981. Dolphins spent longer times at the surface and dove less often at night, indicating lower activity levels at night. Observations of long-distance movement between Texas bays, and an autumn increase in dolphin numbers in the study area, suggested that the study animals were not an isolated population.

Wursig, B. and S. K. Lynn. 1996. Movements, site fidelity, and respiration patterns of bottlenose dolphins on the central Texas coast. NOAA Tech. Mem. NMFS-SEFSC-383, 111 pp.

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Davis, R. W., G. A. J. Worthy, B. Würsig, S. K. Lynn, and F. I. Townsend. 1996. Diving behavior and at-sea movements of an Atlantic spotted dolphin in the Gulf of Mexico. Marine Mammal Science 12(4):569-581.

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Radio-tracking of 10 bottlenose dolphins (Tursiops truncatus), from 9 July 1992 to 13 September 1992, and photographic surveys of 35 freeze-branded dolphins, from May 1992 to June 1993, were conducted in the Matagorda Bay area of Texas, in response to a mass mortality event which occurred between Matagorda and Aransas Bays, Texas, during spring 1992. The primary goals of the study were to assess range size and site fidelity, as well as to initiate a long-term ecological study by collecting data on social and behavioral patterns.

The Matagorda Bay dolphin population was found to be numerically robust, occupying all regions of the bay surveyed. Mean range size, based on radio telemetry, was 140 km2 (SD = 90.7, n = 10 dolphins). Males and females had similar range sizes though males visited the extremities of their ranges more frequently or for longer periods. Most, if not all 35 freeze-branded dolphins, appeared to be resident to the Matagorda-Espiritu Santo Bay area with much fluidity of group membership. Overall mark/recapture population size estimates from photo-identification suggested that 218 ± 71.4 (95% CI) dolphins utilized an area of 312 km2 in Matagorda and Espiritu Santo Bays, similar to an estimate made in 1981. Dolphins spent longer times at the surface and dove less often at night, indicating lower activity levels at night. Observations of long-distance movement between Texas bays, and an autumn increase in dolphin numbers in the study area, suggested that the study animals were not an isolated population.

Lynn, S.K. 1995. Movements, Site Fidelity, and Surfacing Patterns of Bottlenose Dolphins on the Central Texas Coast. M.S. thesis, Texas A&M Univeristy.