摘要:

AbstractThe response of migrating humpback whales to biopsy sampling was investigated off North Stradbroke Island, South East Queensland. Whales were allocated a behavioral category prior to biopsy sampling according to the general behavior of their pod. Behavioral reactions were recorded after each attempt. Sex was determined using a molecular genetic technique.Detectable reactions occurred in 41.6% of successful biopsy attempts, a significantly lower response rate than that reported by two studies carried out on the feeding and breeding grounds of the North Atlantic. There was no difference in the response rate of whales on their northward or southward migration. Pod size was not an important factor in predicting the response of an individual. Females responded to biopsy sampling at a significantly higher rate than males.Our results indicate that a substantial difference in response rate can occur between studies. Factors such as the type of boat used and the prior exposure of whales to human impact may be of importance. Our study suggests that female humpback whales may be particularly responsive to human disturbances. Overall, however, biopsy sampling has minimal impact on humpback whales.

ISSN:0824-0469    

DOI:10.1111/j.1748-7692.1994.tb00496.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractThe rate of occurrence of click trains of two harbor porpoises (Phocoena phocoena) were counted during 14 nights. We developed an echolocation signal detection system that was harnessed to a porpoise and activated a light when the animal emitted an echolocation signal. This device, referred to as a click‐light, detects echolocation signals above 150 dB re 1 μPa in the 28–180 kHz range. Echolocation rates, i.e., occurrences of click trains, changed frequently, ranging from 0 to 25 per minute. Echolocation rates were affected by feeding, individual difference, and enclosure type such as the net enclosure and the pool. The porpoise echolocation rates seemed to show acclima

ISSN:0824-0469    

DOI:10.1111/j.1748-7692.1994.tb00497.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractThis study compared the effects of drug combinations commonly used for chemical restraint of southern elephant seals. The combinations were: ketamine and diazepam, ketamine and midazolam, ketamine and xylazine, and tiletamine and zolazepam. The main aims were to gather basic information regarding the response of the animals to the different combinations, and to determine which were most useful for routine chemical restraint. All drug combinations could be used safely although apnea and whole‐body shaking occurred with each. There were significant differences in several of the responses measured. Poor muscle relaxation and prolonged apnea were associated with ketamine and diazepam use. Animals given ketamine and xylatine were more depressed, took longer to recover, had a higher incidence of thermoregulatory problems, and lower heart rate than after other combinations. Ketamine and midazolam and tiletamine and zolazepam produced fewer complications than the other drug combinations, and tiletamine and zolazepam showed greater predictability of response and ease of use, making it preferable for use by people with little experience in anesthesia of elephant seal

ISSN:0824-0469    

DOI:10.1111/j.1748-7692.1994.tb00498.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractBlood and saliva samples, vaginal swabs, and bioelectric impedance measurements were collected 1–3 times per week from a captive adult female Hawaiian monk seal (Monacbus schauinslandi) during the spring and summer of 1991. During 1992 saliva only was collected on average 4 times weekly. Concentrations of progesterone and estrone sulfate, and the periodic appearance of cornified epithelial cells from the vagina indicated consecutive estrous cycles ranging 35 ± 3 days in duration. Progesterone concentrations in plasma and saliva had a correlation of 0.868, while estrone sulfate had a correlation of 0.982. Bioimpedance of the whole seal body resulted in a pattern similar to the estrone sulfate concentrations, but shifted forward by 2 d. Bioimpedance of the upper vaginal tissues paralleled the estrone sulfate pattern while the bioimpedance of the lower reproductive tract fluctuated without a distinct pattern. The luteal phase ranged 17–20 d and the follicular phase was 15–18 d in length. These results indicate that: (1) the Hawaiian monk seal, in captivity, is a polyestrous seal, in contrast to other phocid seals that have been studied; (2) salivary concentrations of estrogen and progesterone may provide an accurate, less‐invasive method of monitoring reproductive hormones in captive Hawaiian monk seals; and (3) vaginal cytology and bioelectric impedance reflect physiological changes associated with the estro

ISSN:0824-0469    

DOI:10.1111/j.1748-7692.1994.tb00499.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractOperational interactions occur between South African (Cape) fur seals and the purse‐seine fishery in South Africa. Seals eat fish from the nets but the main concern is the activity of seals causing fish to sound, resulting in loss, or partial loss of the catch. Detectable loss occurs on approximately 5% of hauls. In addition to this, smaller quantities may be lost on each haul as seals depress the net float line while moving into and out of the net. The cost of seal interference is difficult to quantify because the mass of fish lost is not known, and the loss is essentially one of additional fishing time required to fill the total allowable catch for the fishery. An estimate of the cost is calculated as between 1.6% and 4.1% of the landed value of the fishery. Some seals are killed by fishermen when they pose a potential threat to the safety of the crew aboard, and some may drown if caught in the net or pump. Overall this is probably fewer than a thousand seals per year. It is also known that if seals are thought to be disturbing the fish, these seals near the nets may be deliberately killed by purse‐seine fishermen. Overall this mortality, whether deliberate or incidental, is probably negligible in terms of the population size of South African fur se

ISSN:0824-0469    

DOI:10.1111/j.1748-7692.1994.tb00500.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

ISSN:0824-0469    

DOI:10.1111/j.1748-7692.1994.tb00501.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

ISSN:0824-0469    

DOI:10.1111/j.1748-7692.1994.tb00502.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

ISSN:0824-0469    

DOI:10.1111/j.1748-7692.1994.tb00503.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

ISSN:0824-0469    

DOI:10.1111/j.1748-7692.1994.tb00504.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

ISSN:0824-0469    

DOI:10.1111/j.1748-7692.1994.tb00505.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY