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P.A. Tuomi

Publications and source records attributed to P.A. Tuomi.

3 recordsLinked to original sources

Effects of ACTH, capture, and short term confinement on glucocorticoid concentrations in harlequin ducks ( Histrionicus histrionicus )

Little is known about baseline concentrations of adrenal hormones and hormonal responses to stress in sea ducks, although significant population declines documented in several species suggest that sea ducks are exposed to increased levels of environmental stress. Such declines have been observed in geographically distinct harlequin duck populations. We performed an adrenocorticotropic hormone (ACTH) challenge to evaluate adrenal function and characterize corticosterone concentrations in captive harlequin ducks and investigated the effects of capture, surgery, and short term confinement on corticosterone concentrations in wild harlequin ducks. Harlequin ducks responded to the ACTH challenge with an average three-fold increase in serum corticosterone concentration approximately 90 min post injection, and a four- to five-fold increase in fecal glucocorticoid concentration 2 to 4 h post injection. Serum corticosterone concentrations in wild harlequin ducks increased within min of capture and elevated levels were found for several hours post capture, indicating that surgery and confinement maintain elevated corticosterone concentrations in this species. Mean corticosterone concentrations in wild harlequin ducks held in temporary captivity were similar to the maximum response levels during the ACTH challenge in captive birds. However, large variation among individuals was observed in responses of wild birds, and we found additional evidence suggesting that corticosterone responses varied between hatch year and after hatch year birds.

Comparative Biochemistry and Physiology, Part A: M

Immobilization of free-ranging male pacific walruses ( Odobenus rosmarus divergens ) with carfentanil citrate and naltrexone hydrochloride

The major challenges in immobilization of free-ranging walruses ( Odobenus rosmarus divergens ) are to produce a deep level of anesthesia very quickly (to avoid darted animals from entering the water and drowning), and to find a drug or drug combination that requires only a small volume to be delivered by dart, is safe, reversible, and that provides an adequate period of immobilization to permit attachment of instruments, phlebotomy, and measuring. Tiletamine-zolazepam is recommended for immobilization of pinnipeds, with inhalant anesthesia recommended for more extensive procedures requiring better analgesia (Gales 1989). Drugs that have been used on free-ranging walruses include ketamine (Hagenbeck et al . 1975), phencyclidine combined with acepromazine (DeMaster et al . 1981), etorphine (Born and Knutsen 1990, Hills 1992, Griffiths et al . 1993), tiletamine-zolazepam (Stirling and Sjare 1988, Griffiths et al . 1993), medetomidine and ketamine (Lydersen et al . 1992), and carfentanil (Hills 1992, Lanthier et al . 1999). Carfentanil but not etorphine is presently licensed and available in the United States. Forty-eight adult male walruses were immobilized with carfentanil citrate in the summers of 1995-1997 at Maggy Beach (58°57’N, 161°76’W), a land haul-out located at Cape Peirce within the Togiak National Wildlife Refuge in southwest Alaska. The number of animals present during immobilizations ranged from three to several thousand. Criteria for choosing individual walruses included good body condition, the presence of two tusks of sufficient diameter for the attachment of radio transmitters, and presence of the animal at the edge of the herd. In addition, we chose animals that were resting quietly and which had not recently hauled out (as judged by skin color). Walruses were darted from ranges of approximately 10-15 m using a Cap-Chur rifle (Palmer Chemical and Equipment Co., Douglasville, Georgia, GA 30133). Carfentanil citrate (Wildlife Pharmaceuticals, Fort Collins, CO 80524) was administered by dart with a 10-cm needle to the lumbar region. Most animals received a dose of 2.7 or 3.0 mg of carfentanil. One animal received a second dose after the first syringe apparently burst on impact. Induction times were measured as being the time at which the animal collapsed, failed to respond to external stimuli, or as the time when the darter stood up and moved towards the animal.

Marine Mammal Science

Procedures and rationale for marking sea otters captured and treated during the T/V Exxon Valdez oil spill

Four methods were used for marking sea otters ( Enhydra lutris ) captured and treated during the response to the T/V Exxon Valdez oil spill. Colored and numbered flipper tags were placed on each sea otter that was brought to the otter treatment centers. These tags allowed individual recognition and permitted the tracking of individuals through the treatment and holding processes. Recovery of tagged carcasses may provide a crude measure of the fates of rehabilitated otters. Seven sea otters were instrumented with radio transmitters attached to flipper tags as part of a pilot release program. The results of that study were inconclusive. Forty-five sea otters were implanted with radio transmitters as part of a study to assess the fate of rehabilitated sea otters. Specific objectives of the study include estimating survived rates and monitoring the reproductive success of the sample of rehabilitated sea otters and comparing the results with similar variables in a control population. Transponder chips were injected in the perianal region of all but seven of the instrumented sea otters, and all were tagged with red flipper tags. The advantages and disadvantages of each type of tag are discussed.

Alaska