[MARMAM] Abstracts, Aquatic Mammals, vol 32, issue 2, June 2006

Dagmar Fertl dfertl at geo-marine.com
Thu Aug 17 15:08:28 PDT 2006


Dear Marmam and ECS-mailbase subscribers,

Apologies in advance, to those of you on both listserves who will receive cross-postings. The following are the contents and abstracts for the most recent issue of _Aquatic Mammals_. This journal was established by the European Association for Aquatic Mammals (EAAM) in 1974; both the EAAM and the European Cetacean Society (ECS) sponsor the journal, which is printed 4 times per year. These abstracts are posted as a courtesy to the Marmam editors and the two societies, as well as the managing editor of _Aquatic Mammals_: Dr. Jeanette Thomas at Western Illinois University-Quad Cities. 

For instructions to authors, abstracts of previous issues, and publication fees, see the journal website: EAAM (http://eaam.org) and ECS (www.broekemaweb.nl/ecs). 

Please do not contact me or the listserve editors for copies of the articles. Instead, please find the addresses of the authors to whom reprint requests and other inquiries should be directed. When an email address was provided with the article, I included it with the article (=only the book reviews have email addresses supplied). Thank you for your continued interest in these postings, as well as other publication postings to the listserves.

With regards,

Dagmar Fertl
Geo-Marine, Inc.
2201 Avenue K, Suite A2
Plano, Texas 75074 USA
972-543-4137
FAX 972-543-4130
dfertl at geo-marine.com
http://www.geo-marine.com
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Mellink, E.*, and A. Orozco-Meyer. 2006. Abundance, distribution, and Residence of bottlenose dolphins (_Tursiops truncatus_) in the Bahía San Jorge area, northern Gulf of California, México. _Aquatic Mammals_ 32(2): 133-139. 

*Centro de Investigacion Cientifica y de Educacion Superior de Ensenada, BC

We studied bottlenose dolphins (_Tursiops truncatus_) in Bahía San Jorge, northern Gulf of California, México, between August 1999 and March 2000. From a fishing skiff, we photo-characterized dolphins and noted their location, and from a raised platform on shore, we counted dolphins entering and exiting the bay. During our study, the area of Bahía San Jorge seemed to be important for bottlenose dolphins' feeding, especially in the winter, and also apparently for parturition. Most dolphins were only temporarily present in the area. There were no effects of tidal conditions on the numbers or activity of the dolphins. We documented few interactions between artisanal fishermen and dolphins. Only during the shrimp-fishing season, when the dolphins benefited from fishing, were some losses to the fishermen caused through net rupture and catch shaken from the net.
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Rossi-Santos, M.R.*, and L.L. Wedekin. 2006. Evidence of bottom contact behavior by estuarine dolphins (_Sotalia guianensis_) on the eastern coast of Brazil. _Aquatic Mammals_ 32(2):140-144.

*Projeto Boto Sotalia do Sul da Bahia, Instituto Baleia Jubarte/Brazilian Humpback Whale Institute, Rua Barao do Rio Branco, 26, Canavelas BA 45900-000 Brazil

We present herein the first records of evidence of bottom contact behavior by _Sotalia guianensis_. From April 2002 to December 2004, boat cruises were conducted along a 135-km stretch of coast on the Abrolhos Bank, eastern coast of Brazil. Evidence of bottom contact behavior was observed directly or through photographs on 25 occasions during the study period. On 16 occasions, one or more dolphins were observed with mud adhered to their dorsum, flanks, peduncle, head/melon, or dorsal fin. On five occasions, a mud-plume suspended by the movement of the dolphins and their contact with the bottom was observed. During four other occasions, both types of evidence (mud adhered to the body and mud-plume) were observed for the same group of dolphins. Contact by cetaceans with the sea floor is widely reported for several species and seems mainly related to feeding behavior, which probably is also the case for the observation presented here.
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Blanchet, M-A*, G. Desportes, T. Nance, and C. Vanman. 2006. Description of the pregnancies, labours, and pre- and post-partum events of two harbour seals (_Phoca vitulina_) in a zoological environment. _Aquatic Mammals_ 32(2):145-151.

*Fjord & Boelt, Margrethes Plads 1, 5300 Kerteminde, Denmark

Harbour seal (_Phoca vitulina_) births occur frequently in captive environments, yet little data have been published on observations associated with these events. We describe the quasi-simultaneous pregnancies and labours of two primiparous harbour seals at the Danish aquarium and research facility, Fjord & Baelt. There were considerable differences between these two females in their behaviour, the duration/frequency of labour contractions, and the postpartum events. One had a difficult labour, with an extended expulsion phase, and delivered a stillborn pup. The other successfully gave birth to a female. The physiological mechanisms regulating the food intake during pregnancy and lactation in harbour seals are unknown; however, observations during this study of both the increases in food intake during pregnancy and the cessation of eating when labour was imminent suggest that there may be similarities with other mammals, such as humans, cows, and minks, in which these processes involve leptin, a hormone involved in metabolism regulation. Whether this is indeed the case for harbour seals is unknown and is a recommendation for future studies as is the recording of birthing processes in captive environments. Such a database on birth may provide comparative indicators of labour progress, speed, and outcome.
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Königson, S.J.*, K.E. Lundström, M.M.B. Hemmingsson, S-G Lunneryd, and H. Westerberg. 2006. Feeding preferences of harbour seals (Phoca vitulina) specialised in raiding fishing gear. _Aquatic Mammals_ 32(2):152-156.

*Swedish Board of Fisheries, Box 423, 401 96 Goteborg, Sweden

The Swedish eel (_Anguilla Anguilla_) fishery has suffered an increase both in damage to fishing gear and in catch losses caused by harbour seals (_Phoca vitulina_). Eel fyke nets, which are the principal type of fishing gear used, tend to incidentally catch species like cod (_Gadus morhua_), flounder (_Platichthys flesus_), and eelpout (Zoarces viviparus). These are species known to be important in the harbour seals' diet. This raised the issue of whether it is the eels or the by-caught species, which attract harbour seals to attack fyke nets. To examine this question, trials were made with experimental fyke nets in three geographically separated areas within the Archipelago of Göteborg. In each area, fyke nets with two bags each were baited with eels in one bag and cod, flounder, or eelpout in the other. In all three areas, the harbour seals showed a clear preference for eels in the fyke nets. The results indicated that certain harbour seals specialise in foraging at fyke nets and have developed different feeding preferences compared to other seals. Knowledge about harbour seals' behaviour around fishing gear is important and will be useful in the development of seal-safe fishing gear to prevent damage caused by harbour seals. 
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Reif, J.S.*, M.M. Kliks, A.A. Aguirre, D.L. Borjesson, L. Kashinsky, R.C. Braun, and G.A. Antonelis, George A. 2006. Gastrointestinal helminths in the Hawaiian monk seal (_Monachus schauinslandi_): Associations with body size, hematology, and serum chemistry. _Aquatic Mammals_ 32(2):157-167.

*Department of Environmental Health, Colorado State University, Fort Collins, CO 80523, USA

Gastrointestinal helminth parasites are found commonly in the Hawaiian monk seal (_Monachus schauinslandi_), the most endangered seal in the United States and one of the world's most endangered pinnipeds. We studied potential associations between gastrointestinal helminth infections and body size, and hematologic and serum chemistry variables in a sample of 282 monk seals captured between 1998 and 2002 as part of a population health assessment. Based on the presence of eggs in feces, the highest prevalence of infection (78%) was for cestodes belonging to a complex of several _Diphyllobothrium_ spp. Infections with the nematode _Contracaecum turgidum_ were found in 29% of samples tested. Eggs of the acanthocephalan _Corynosoma rauschi_ were found in 4% of seals examined; and the feces of four weanling seals on the French Frigate Shoals contained eggs of the recently described trematode, _Heterophyopsis hawaiiensis_. We used a general linear model and analysis of variance techniques with adjustment for subpopulation and age to determine whether infections with _Diphyllobothrium_ spp. or _C. turgidum_ were associated with changes in hematologic or serum chemistry variables and found little evidence of an effect when we compared infected with negative seals or seals in the highest quartile of egg counts with negative seals. We also conducted analyses of associations between infection and morphometric values in adjusted, age-stratified data. Infection with _Diphyllobothrium_ spp. was associated with a decrease in axillary girth and an increase in dorsal standard length/axillary girth ratio in seals less than 2 y of age, with the effects most pronounced in seals less than 1 y of age. After adjustment for _Diphyllobothrium_ spp., __C. turgidum_ infection was not associated with morphometric parameters. Co-infection with _Diphyllobothrium_ spp. and _C. turgidum_ was not associated with differences in body size greater than those found with diphyllobothriid tapeworm infection alone. These findings suggest that intervention strategies to reduce the prevalence of tapeworm infections in immature Hawaiian monk seals should be considered as a conservation measure for this highly endangered marine mammal.
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Petrauskas, L.R.*, and S.K. Atkinson. 2006. Variation of fecal corticosterone concentrations in captive Steller sea lions (_Eumetopias jubatus_) in relation to season and behavior. _Aquatic Mammals_ 32(2):168-174.

*School of Fisheries and Ocean Sciences, University of Alaska-Fairbanks, P.O. Box 730, Seward, AK 99664, USA

Little information is available regarding the adrenal activity of Steller sea lions (_Eumetopias jubatus_) in relation to season and behavior. The objective of this study was to test for seasonal changes in fecal corticosterone concentrations and potential relationships to behavioral scoring in captive Steller sea lions. For this study, fecal samples were obtained opportunistically over a 3-y period (September 2001 to September 2004) from three adult (1 male, 2 female), reproductively intact, long-term captive Steller sea lions housed at the Alaska SeaLife Center in Seward, Alaska. Daily behavior scores based on a scale of 1 (poor) to 5 (excellent) of appetite, energy, attention, sociability, and enrichment were also recorded. The male (SSL-01) had a significantly higher fecal corticosterone concentration in the breeding season, while one of the females (SSL-03) had a significantly higher fecal corticosterone concentration in between the molting and breeding seasons. Fecal corticosterone concentration was significantly higher for one of the females (SSL-03) in comparison to the other female (SSL-02; p < 0.001). There was a significant negative relationship between behavior score and fecal corticosterone concentrations for the male and one female (SSL-03). The results of this study do indicate that Steller sea lions have a highly seasonal physiology that can be reflected in the fecal corticosterone concentrations of both sexes.
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Terhune, J.M.*, and A. Dell'Apa. 2006. Stereotyped calling patterns of a male Weddell seal (_Leptonychotes weddellii_). _Aquatic Mammals_ 32(2):175-181. 

*Department of Biology, University of New Brunswick, P.O. Box 5050, Saint John, NB, E2L 4L5 Canada

Underwater calling behaviour between breathing bouts of a single adult male Weddell seal (_Leptonychotes weddellii_) was examined with respect to call type and timing late in the breeding season at Davis Station, Antarctica. Underwater calls and breathing sounds were recorded on 1 and 8 December 1997. Thirty-seven sequences of calls prior to surfacing to breathe and 36 post-submerging sets of calls were analyzed with respect to probability of call type occurrence and timing. Dives were 461 ± 259 s (mean ± S.D.). The seal called every 29.7 ± 56.2 s throughout a dive. The first call after submerging was usually (n = 29 of 36) a low frequency (< 0.8 kHz) growl. Three patterns of three-to five-call type sequences were made following 28 of 36 breathing bouts. Call type patterns after submerging exhibited fewer different sequences than those before surfacing (χ2 = 61.42, DF = 4, p < 0.000001). The call usage patterns before surfacing were diverse and did not indicate when the seal was going to surface, a time when he would be vulnerable to attack from below. Our findings suggest the hypotheses that territorial male Weddell seals call throughout each dive and use stereotyped call patterns to identify themselves while vocally asserting dominance.
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Fair, P.A.*, T.C. Hulsey, R.A. Varela, J.D. Goldstein, J. Adams, E.S. Zolman, and G.D. Bossart. 2006. Hematology, serum chemistry, and cytology findings from apparently healthy Atlantic bottlenose dolphins (_Tursiops truncatus_) inhabiting the estuarine waters of Charleston, South Carolina. _Aquatic Mammals_ 32(2):182-195. 

*National Oceanic and Atmospheric Administration, National Ocean Service, Center for Coastal Environmental Health and Biomecular Research, Charleston, SC 29412, USA

This study reports comprehensive baseline data for hematology, serum chemistry, and cytology variables in 63 apparently healthy Atlantic bottlenose dolphins (_Tursiops truncatus_) inhabiting the estuarine waters of Charleston (CHS), South Carolina (SC). Blood and cytology samples were collected from bottlenose dolphins in August 2003 and August 2004 during capture-release health assessment studies. Means, medians, standard deviations, 95% CI, and ranges were calculated for the population's hematology, serum biochemistry, and serum protein electrophoresis parameters. All of the parameters for which a published range was available were close to or within the ranges previously reported. Comparisons by age, gender, and pregnancy status revealed statistically significant differences (p < 0.05) for several hematology and serum chemistry parameters. Blowhole, rectal, and gastric swabs were examined for cytologic abnormalities, utilizing light microscopy. There were no pathologic findings in the samples; however, 4% (2/51) of the dolphins sampled had mild or moderate blowhole inflammation. The prevalence of gastric inflammation was 26% (13/50), and severe gastric inflammation was present in three of the dolphins sampled (6%). The majority of animals with gastric inflammation were male (10/13, 77%). In fact, all cases of severe inflammation occurred in males, and none were present in 2004. These data provide a baseline from which to compare hematological, serum chemistry, and cytological parameters in wild dolphin populations.
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Lanyon, J.M.*, R.W. Slade, H.L. Sneath, D. Broderick, J.M. Kirkwood, D. Limpus, C.J. Limpus, and T.A. Jessop. 2006. A method for capturing dugongs (_Dugong dugon_) in open water. _Aquatic Mammals_ 32(2):196-201. 

*School of Integrative Biology, The University of Queensland, St. Lucia, QLD, 4072, Australia

We developed a method to rapidly and safely live capture wild dugongs based on the "rodeo method" employed to catch marine turtles. This method entails close pursuit of a dugong by boat until it is fatigued. The dugong is then caught around the peduncle region by a catcher leaping off the boat, and the dugong is restrained at the water surface by several people while data are collected. Our sampling protocol involves a short restraint time, typically < 5 min. No ropes or nets were attached to the dugong to avoid the risk of entanglement and subsequent drowning. This method is suitable for shallow, open-water captures when weather and water conditions are fair, and may be adapted for deeper waters.
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Gannier, A.*, and E. Petiau. 2006. Environmental variables affecting the residence of spinner dolphins (_Stenella longirostris_) in a Bay of Tahiti (French Polynesia). _Aquatic Mammals_ 32(2):202-211.
 
*Groupe de Recherche sur les Cetaces, BP 715, 06633 Antibes Cedex, France

The spinner dolphin (_Stenella longirostris_) is the most common among 16 species in the Society Islands (French Polynesia). They are observed year-round during daytime in sheltered bays or within lagoons. From 1995 to 2002, we studied spinner dolphins from a shore site in Baie des Pêcheurs, a bay on the west coast of Tahiti, performing 1,033 sighting sessions with binoculars. Presence, position, and school size were noted, as well as various behavioral and environmental variables. Human presence also was recorded. Dolphins were present on average 73.3% of the days, with a higher presence rate from May to November (81.0%) than from December to April (66.7%). Dolphins stayed within the bay from early morning until 1200 to 1500 h and had school sizes ranging from as small as 15 to 30 to as large as 100 to 140 individuals. Dolphins began to move slowly offshore after 1100 h. On average, they stayed 400 m from shore, although they approached as close as 100 to 150 m. Dolphin presence and residence time seemed to be negatively affected by surface water turbidity (river flow) and lagoon current strength. Recreational dolphin watching was low from Monday to Thursday (0.20 to 0.35 boat per sighting session) and high on Sunday, with an average of 1.67 boats per session. There was a lower dolphin presence rate from Monday to Thursday (69%) than from Friday to Sunday (78%). Presence patterns were similar to those found in Hawaii, accounting for differences in environmental characteristics.
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Fazioli, K.L.*, S. Hofmann, and R.S. Wells. 2006. Use of Gulf of Mexico coastal waters by distinct assemblages of bottlenose dolphins (_Tursiops truncatus_). _Aquatic Mammals_ 32(2):212-222.

*Chicago Zoological Society, c/o Mote Marine Laboratory, 1600 Ken Thompson Parkway, Sarasota, FL 34236, USA

Management and conservation decisions affecting coastal bottlenose dolphins (_Tursiops truncatus_) benefit from consideration of population parameters such as population size, stability, distribution, habitat use, and gene flow, as well as social organization patterns. Long-term study of bottlenose dolphins in inshore areas suggested population units are based on the social structure and habitat use of resident dolphins, but little is known about dolphins in open coastal waters just offshore. This study examined the stock structure of bottlenose dolphins in an open coastal habitat, made comparisons to adjacent inshore population units, and evaluated interactions between dolphins in these two regions. We conducted a 14-mo boat-based photographic identification study along 93 km of the west coast of Florida, extending 9.3 km offshore. We identified 580 individual dolphins in the study area and designated these individuals as "Inshore" (long-term bay residents) or "Gulf" (observed predominantly in Gulf waters) regional population units. Dolphins used the Gulf habitat differently, depending on season and regional designation. Sighting frequencies of "Gulf" dolphins suggested patterns of seasonal residency, extended geographic range out of the study area, or transience, with fewer individuals displaying year-round residence. In general, dolphins in this coastal region appear to divide into overlapping communities defined by preferred geographic ranges, habitat use patterns, and social associations.
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Anderson, R.C.*, R. Clark, P.T. Madsen, C. Johnson, J. Kiszka, and O. Breysse. 2006. Observations of Longman's beaked whale (_Indopacetus pacificus_) in the western Indian Ocean. _Aquatic Mammals_ 32(2):223-231. 

*P.O. Box 2074, Male, Republic of Maldives

Seventeen new sightings, and a total of 32 records, of the little-known Longman's beaked whale, (_Indopacetus pacificus_) (also called tropical bottlenose whale or Indo-pacific beaked whale) are reported from the western Indian Ocean. Field identification features are reviewed, and the possibilities of confusion with other beaked whales are noted. Mean group size for the western Indian Ocean sightings was 7.2 individuals (n = 22, SD = 10.9, range = 1 to 40). This is smaller than previously published estimates from the Pacific, reflecting a relatively large number of new sightings of individuals and small groups, which, in turn, reflect the recent description of the external appearance of this species. Recorded dive times were either short (mean = 14 min, range = 11 to 18 min, n = 5) or long (mean = 26 min, range = 20 to 33 min, n = 19). Longman's beaked whales appear to be widely distributed in the warmer (> 27° C) waters of the western Indian Ocean, but most sightings were over or adjacent to deep slopes (depths 250 to 2,000+ m). Mean sighting rates were much higher in the western Indian Ocean (1 sighting per 31 sea days for visual surveys) and particularly around the Maldives (1 sighting per 21 sea days) than have been reported from the Pacific (1 sighting per 200 sea days). Longman's beaked whales may therefore be more common in the western Indian Ocean than in the Pacific, although survey methodologies used in the two oceans were not identical. Widespread gillnet fisheries may pose a potential threat to this species in the Indian Ocean.
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Galatius, A.* 2006. Bilateral directional asymmetry of the appendicular skeleton of the white-beaked dolphin (_Lagenorhynchus albirostris_). _Aquatic Mammals_ 32(2):232-235. 

*Department of Cell Biology and Comparative Zoology, Institute of Biology, University of Copenhagen, Universitetsparken 15, DK-2100 Copenhagen Ø, Denmark

Bilateral directional asymmetry of the lengths and diameters of the scapula, humerus, radius, and ulna were analyzed on a sample of 38 white-beaked dolphins (_Lagenorhynchus albirostris_) from Danish waters. The levels of asymmetry were consistent between the sexes and between physically mature and immature animals. The length and diameter of the humerus and the length of the radius showed significant asymmetry, all favouring the right side. The greatest asymmetry was found in the diameter of the humerus (1.88% SE 0.36). The results were somewhat different from what is known in the harbour porpoise (_Phocoena phocoena_) that show asymmetry favouring the right side in all of the dimensions investigated here. This may indicate a different pattern of employment of the flippers. The detected asymmetries, along with the many examples of lateralized behaviour recorded in cetaceans, point to the existence of lateralized use of the flippers in the white-beaked dolphin and possibly other delphinid and cetacean species. Although some evidence exists for flipper preference in the baleen humpback whale (Megaptera novaengliae) and turning preferences in other species, this needs to be confirmed through further behavioural studies.
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Atem, A.C.G.*, and E.L.A. Monteiro-Filho. 2006. Nocturnal activity of the estuarine dolphin (_Sotalia guianensis_) in the region of Cananéia, São Paulo State, Brazil. _Aquatic Mammals_ 32(2):236-241.

*Instituto de Pesquisas Cananeia, Rua Joao Salim, Lote 26, Quadra Y Parque Xangrila, CEP 13098-606, Campinas-SP Brazil

The study of the nocturnal activity of the estuarine dolphin (_Sotalia guianensis_) was conducted in Cananéia on the southern coast of São Paulo state. The observations were made between March and October of 2003, which included 22 field outings resulting in a total of 66 h of field work. Two procedures were used: (1) visual observation of behaviours, using the focal-animal method; and (2) recording and acoustic monitoring of the animals. Observations were made during the nocturnal period from a medium-sized boat, illuminated by a crescent or full moon, which allowed easy observation of the behaviours. In view of the need to learn more about the biology and ecology of _S. guianensis_, the objectives of this study were to follow the behaviours of dolphins at night using only moonlight, describe the behavioural patterns displayed, and determine the activities of the dolphins using acoustic monitoring. Observation of dolphins with the help of moonlight was demonstrated to be an effective means of observing the animals, but at the same time, it did present some difficulties. Behaviours were described using a combination of empirical and functional methods, and then they were compared to those described by other investigators. All the behaviours observed for _S. guianensis_ during the nocturnal period—diving, hunting, and leaping—were the same as those seen, named, and described by other authors for the diurnal period.
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Würsig, B. 2006. Book Review: _Marine Mammal Research: Conservation Beyond Crisis_, editors: J.E. Reynolds III, W.E. Perrin, R.R. Reeves, S. Montgomery, and T.J. Ragen. John Hopkins University Press, Baltimore, Maryland, USA. __Aquatic Mammals__ 32(2):242-243.

Texas A&M University at Galveston, 4700 Avenue U, Bldg 303, Galveston, Texas, USA; wursigb at tamug.edu
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Moore, M.J. 2006. Book Review: _Whale_, by J. Roman, Reaktion Books. _Aquatic Mammals_ 32(2):244-245.

Biology Department, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, USA; mmoore at whoi.edu 







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