Dear Marmam and ECS-mailbase subscribers, Apologies in advance to those of you who will be receiving cross-postings. The following is a list of contents of the most recent issue of _Aquatic Mammals_. This publication is supported through a partnership between the European Association for Aquatic Mammals and the European Cetacean Society. For more information on _Aquatic Mammals_, I refer you to the new website for the publication (that includes author guidelines) which not only also has links to both societies: http://www.wiu.edu/users/aquamamm/index/home.htm The abstracts are posted as a courtesy to the journal editors: Managing Editor: Dr. Jeannette Thomas, Department of Biological Sciences, Western Illinois University-Quad Cities, 3561 Street, Moline, Illinois 61265, USA (J-Thomas@wiu.edu; tel: 309-762-9481; fax: 309-762-6989) and Co-Editor and Book Review Editor: Dr. Kathleen Dudzinski, Mystic Aquarium & Institute for Exploration, 55 Coogan Avenue, Mystic, Connecticut 06355, USA (kdudzinski@mysticaquarium.org; tel: 860-572-5955; fax: 860-572-5969). The addresses to whom reprint inquiries should be directed is included with each article. No email addresses were provided with any of the articles. Thank you for your continued interest in this journal and publication postings in general. With warm regards, Dagmar Fertl Geo-Marine, Inc. dfertl@geo-marine.com http://www.geo-marine.com ____________________________________________________________________________ Neumann, D.R.*, and M.B. Orams. 2006. Impacts of ecotourism on short-beaked common dolphins (Delphinus delphis) in Mercury Bay, New Zealand. Aquatic Mammals 32(1):1-9. *Luisenstrasse 2, 76530 Baden-Baden, Germany Short-beaked common dolphins (Delphinus delphis) often are found in large aggregations offshore from the eastern coast of New Zealand. They are the primary target of at least six marine mammal tourism operations from Whakatane to the Hauraki Gulf. This report details the first long-term investigation of interactions between tourists and common dolphins. During a 3-y study offshore from Whitianga on the Coromandel Peninsula, 105 focal group follows, totaling 118 h of observations were conducted from a 5.5-m, rigid-hull inflatable boat. Seventy-two of these observations were conducted in the absence of the tour boat (baseline), and 33 with the tour boat. Baseline data were compared with "tour boat" data to assess changes in dolphin behaviour resulting from the tour boat approaching and swimmers entering the water to snorkel with the dolphins. Common dolphins responded with a relatively predictable pattern to approaching boats. Initial attraction (mean duration 8 min) typically was followed by neutral behaviour (mean duration 57 min) and eventually replaced by boat avoidance. Smaller dolphin groups showed boat avoidance sooner and more frequently than larger groups. When swimmers entered the water, dolphins only spent an average of 2 min in their vicinity. Throughout encounters, they maintained a distance of at least 3 m from the nearest swimmer. During half of the attempted swims, dolphins did not change their course or their activity in response to swimmers. Swimmers had a better chance of a sustained interaction when the group of dolphins was large (> 50 individuals) and/or the number of swimmers in the water was small (< 5). The results of this study suggested that common dolphins can be affected by tourism; however, adherence to New Zealand's Marine Mammals Protection Regulations and the current low level of tourism appear to minimise the impact on this species. ******************************************************************* Weiss, J.* 2006. Foraging habitats and associated preferential foraging specializations of bottlenose dolphin (Tursiops truncatus) mother-calf pairs. Aquatic Mammals 32(1):10-19. Current address: Geo-Marine, Inc. 2713 Magruder Boulevard, Suite D, Hampton, VA 23666, USA Bottlenose dolphins (Tursiops truncatus) use a variety of foraging specializations to detect and pursue prey. Like other mammals, individual dolphins may use specialized foraging techniques that are shaped in response to habitat type or prey resources. The long duration of the mother-calf bond presents an opportunity for mothers to transmit such specializations to their calves. This study explored how the use of foraging specializations may influence selection of foraging habitats and how such specializations may spread within a dolphin community. Focal animal follows were used to document the foraging behavior of five resident females and their calves from June to August 2003 in Sarasota Bay, Florida. Sarasota Bay was classified into six habitat types based upon bathymetry and bottom topography. Individual females differed in their selection of foraging habitats. Three of the five focal females used one of two foraging specializations—kerplunking and barrier-feeding—and exhibited a preference for only one type of behavior. A significant difference in the frequency of observations of foraging specific behaviors was found between different habitat types. Limited observations, as well as anecdotal evidence from past studies, suggest that maternal transmission may play a role in the spread of foraging techniques, such as kerplunking and barrier-feeding, within the community. My findings suggest that the use of foraging specializations is associated with foraging habitat preferences in Sarasota Bay. The importance of seagrass areas to foraging dolphins and the significance of the mother-calf bond to the development of the use of foraging specializations is emphasized. *********************************************************************** Reyes, L.M.* 2006. Cetaceans of central Patagonia, Argentina. Aquatic Mammals 32(1):20-30 *Universidad Nacional de la Patagonia San Juan Bosco, Boulevard Brown 3700, (9120) Puerto Madryn, Chubut, Argentina The aim of this study was to produce the first annotated checklist of cetaceans found in the coastal waters of central Patagonia, Argentina, in the Southwestern Atlantic, encompassing approximately 700 km of coastline. Personal records of sightings and strandings, personal communications with trained individuals, photographs, unpublished abstracts from meetings, scientific publications, newspaper articles, and specimen collections from academic institutions were considered. Thirteen species were reported in the area, including ten odontocetes and three mysticetes. Reports of eight species had been published previously, including Cephalorhynchus commersonii, Lagenorhynchus obscurus, L. australis, Orcinus orca, Globicephala melas, Physeter macrocephalus, Mesoplodon layardii, and Ziphius cavirostris. Five species were formally documented for the first time in this coastal area, including Grampus griseus, M. grayi, Eubalaena australis, Balaenoptera bonaerensis, and B. musculus. The number of odontocete species and the presence of three species of pinnipeds breeding or moulting on several islands (Otaria flavescens, Arctocephalus australis, and Mirounga leonina) highlight the importance of the area in terms of biodiversity of top predators and the need for the creation of a new Marine Protected Area, considering present uses and trends in coastal development. *********************************************************************** McFadden, K.W.*, G.A.J. Worthy, and T.E. Lacher. 2006. Photogrammetric estimates of size and mass in Hawaiian monk seals (Monachus schauinslandi). Aquatic Mammals 32(1): 31-40. *current address: National Marine Fisheries Service, Office of Protected Resources Division, Silver Spring, MD 20910, USA A non-invasive photographic technique was developed to estimate the body mass of Hawaiian monk seals (Monachus schauinslandi). Newly weaned monk seal pups (n = 31) were photographed and measured at Kure Atoll in the northwestern Hawaiian Islands. Length, side area, anterior/posterior area, and perimeter were measured from photographs to establish predictive relationships with body mass using regression analyses. Photographs were ranked subjectively in terms of quality, based on the degree to which the seal's body position deviated from the ideal position used to obtain standardized photographs. Results indicated that deviations in body positioning (e. g., a seal rolled on its side) did not significantly alter photogrammetric (surface area or perimeter) values compared to those obtained in a standard position. Although the most reliable models (based on information criterion analysis and 95% CIs) were based on directly measured morphological variables, models using only photogrammetric variables also yielded practical and reliable models with 95% CI, ranging from ± 4.95 to 9.12 kg and R2 values from 0.93 to 0.77. This finding indicated that the use of photogrammetry alone to assess body condition is suitable to estimate body mass in 10- to 120-kg weaned Hawaiian monk seal pups. *********************************************************************** Ortiz, R.M.*, and G.A.J. Worthy. 2006. Body composition and water turnover rates of bottle-fed West Indian manatee (Trichechus manatus) calves. Aquatic Mammals 32(1):41-45. *current address: Division of Natural Sciences, University of California, Merced, CA 95344-0039, USA Estimation of body composition and water turnover rates can provide important indices of an animal's health and well-being. This data becomes especially important for a highly endangered species, such as the West Indian manatee (Trichechus manatus). Information on body composition and water turnover rates in nursing manatee calves is unavailable; therefore, the present study describes a unique opportunity to estimate, by isotopic dilution, body composition and water flux in vivo in bottle-fed calves of the West Indian manatee held in captivity. A calf held in fresh water was measured at 9 mo (124.8 kg) and 12 mo (152.6 kg) to examine the effects of growth. Over this 3-mo period, absolute fat mass (FM) increased 70.4% and absolute water turnover rate increased from 4.7 to 9.7 l/d, illustrating how these parameters change as a function of the animal's growth. To examine the effects of salinity on water flux, another calf (110.0 kg), held in salt water, was restricted from fresh water. During freshwater restriction, the calf's water turnover rate was 2.9 l/d and could be accounted for solely by dietary and metabolic water. When the animal was given access to fresh water, turnover rate increased to 4.0 l/d, for which 1.3 l/d could not be accounted, suggesting that nursing calves do not drink salt water. Collectively, the results provide a unique data set for nursing manatee calves and suggest that nursing calves, similar to adults, do not engage in mariposia. In addition, nursing calves will drink when given access to fresh water; however, the contribution of drinking fresh water to the growth and development of nursing calves remains to be examined. These data should provide useful information when implementing the proper husbandry and management plans for both fresh- and saltwater habitats of such a highly endangered species as the West Indian manatee. ********************************************************** Turner, J.P.*, L.S. Clark, E.M. Haubold, G.A.J. Worthy, and D.F. Cowan. 2006. Organ weights and growth profiles in bottlenose dolphins (Tursiops truncatus) from the northwestern Gulf of Mexico. Aquatic Mammals 32(1):46-57. *current address: Department of Marine Science, University of Hawai’i at Hilo, Hilo, HI 96720, USA Systematic necropsies were performed on 63 bottlenose dolphins (Tursiops truncatus), and data on organ mass, standard body length (SBL), body mass (BM), gender, sexual maturity, and age were measured and/or estimated. Animals were extremely fresh and recovered from along the Texas and Louisiana coastline in the northwestern Gulf of Mexico. Organ reference tables were established for this species to facilitate comparisons with other bottlenose dolphins and to provide a baseline for other cetacean species. Organs examined included lungs, adrenal glands, kidneys, testes, ovaries, heart, liver, pancreas, brain, pituitary, thyroid, thymus, and spleen. Individuals were separated into three size classes: < 175 cm, 175-225 cm, and > 225 cm, based on SBL to further facilitate comparisons. Growth rates of length and mass were described using Gompertz nonlinear models as a function of gender. No sexual dimorphism was identified in BM or organ weights, and SBL was only significantly larger for older mature males. SBL and BM were strongly correlated with age when all animals were included in analyses, although this is not an accurate predictor of age, especially in older individuals. Organ weights were significantly correlated with both SBL (except thymus and spleen) and BM (except left ovary, spleen, and thymus). Age was significantly correlated with all organ weights (except thymus, thyroid, and ovaries). There were no significant differences in the weight of any paired organs (adrenal glands, kidneys, lungs, ovaries, testes), and all were significantly correlated with BM. These data on organ weights of bottlenose dolphins, when interpreted with SBL, BM, and age, are significant tools for pathologists and veterinarians interpreting animal health status. ******************************************************************* Mellish, J.E.*, D.G. Calkins, D.R. Christen, M. Horning, L.D. Rea, and S.K. Atkinson. 2006. Temporary captivity as a research tool: Comprehensive study of wild pinnipeds under controlled conditions. Aquatic Mammals 32(1):58-65. *School of Fisheries and Ocean Sciences, University of Alaska-Fairbanks, Fairbanks, AK 99775, USA A new approach to the study of free-ranging, endangered western stock Steller sea lions (Eumetopias jubatus) was implemented at the Alaska SeaLife Center in Seward, Alaska. Groups of up to four juvenile (n = 16) Steller sea lions were held in temporary quarantine for research periods of up to three months. Hematological and blood chemistry parameters were collected at the beginning and end of captivity and compared to free-ranging juvenile controls to determine if animals in temporary captivity can provide accurate physiological data representative of their wild counterparts. Free-ranging pups and juveniles were compared for hematological differences related to developmental stage. Overall, temporarily captive animals did not differ from free-ranging juveniles. Seven of 17 blood parameters measured changed significantly during captivity, likely as a function of a regular schedule and low-impact nutritional studies (e.g., increased mass, cholesterol, total protein, and globulins). A decrease in white blood cells during the study period (10.4 ± 0.59 to 7.9 ± 0.33 m/mm3) to levels lower than that of free-ranging animals (10.7 ± 0.40 m/mm3) indicated a drop in overall stress during captivity despite research and handling procedures. Calcium increased with captivity duration, suggesting that physiological changes can begin in even limited time frames. Eight parameters related to immune status and diet differed significantly between juveniles and pups from the same geographical region. A strategy that combines the benefits of an extended research design with temporary holding of free-ranging animals is proposed as an alternative to traditional field methods for some types of focused physiological studies. ******************************************************************** Fellner, W.*, K. Odell, A. Corwin, L. Davis, C. Goonen, I. Larkin, and M.A. Stamper. 2006. Response to conditioned stimuli by two rehabilitated and released West Indian manatees (Trichechus manatus latirostris). Aquatic Mammals 32(1):66-74. *The Living Seas, Epcot, Walt Disney World Resort, Lake Buena Vista, FL 32830, USA U.S. regulations discourage research that requires training with West Indian manatees (Trichechus manatus latirostris) due to the concern that trained manatees would become accustomed to approaching humans for food and would continue to approach people once released back to the wild. Learning theory suggests that behaviors acquired while in captivity may not transfer well to the new context of the wild habitat, however. In this study, two female, rehabilitating manatees were trained to perform up to five husbandry behaviors. Prior to their release, the behaviors were no longer reinforced. Response to training signals was reduced for all behaviors when reinforcement was with-held. In post-release observations, the manatees were located by satellite and radio-telemetry, and training signals were presented. Neither manatee performed any of the trained behaviors. The results of this case study suggest that training releasable manatees may be a viable option. ******************************************************************** Kjeld, M.*, Ö Ólafsson, G. Víkingsson, and J. Sigurjónsson. 2006. Sex hormones and reproductive status of the North Atlantic fin whales (Balaenoptera physalus) during the feeding season. Aquatic Mammals 31(2):75-84. *The University Hospital, Department of Clinical Chemistry, K-bygging, Landspítalinn v Hringbraut, 101 Reykjavík, Iceland Reproductive fin whales (Balaenoptera physalus) (448 females and 278 males), classified by anatomical/histological methods, were studied for serum sex hormones. Of the 207 females classified as pregnant by anatomical methods, 95% had progesterone (P) levels higher than 9.0 nmol/l with a near symmetrical distribution of log10 P-levels around the mean of 1.55 (35.5 nmol/l geometric mean). More than half of the sexually immature females (n = 157) had P-levels ≤ 0.1 nmol/l. Nonpregnant mature cows were older on average than pregnant cows, suggesting the beginning of reproductive senescence in females before the age of 30 y. The mean serum testosterone (T) of mature males (3.1 nmol/l) was significantly higher than that of immature males (1.0 nmol/l). In mature males, T-levels were positively associated with testicular size, as well as time (day-count) during the summer whaling season. For fin whales, serum P- and T-levels agreed closely with anatomical studies of reproduction and may be decisive when anatomical indexes fail. Furthermore, the serum T-level appears to be an excellent index for monitoring the latter part of the annual male reproductive cycle. *********************************************************************** Trites, A.W.*, B.P. Porter, V.B. Deecke, A/P. Coombs, M.L. Marcotte, D.A.S. Rosen. 2006. Insights into the timing of weaning and the attendance patterns of lactating Steller sea lions (Eumetopias jubatus) in Alaska during winter, spring, and summer. Aquatic Mammals 32(1):85-97. *Marine Mammal Research Unit, Fisheries Centre, University of British Columbia, Room 247, AERL, 2002 Main Mall, Vancouver, BC, V6T IZ4 Behavioral observations of lactating Steller sea lions (Eumetopias jubatus) and their offspring were recorded at four haulout sites in Alaska to determine (1) whether sea lions wean during winter while they are 7 to 9 mo old and (2) whether sea lions using sites in the Gulf of Alaska (the declining endangered population) made longer foraging trips than sea lions in southeast Alaska (where the population appeared larger and healthier). Longer foraging trips are commonly thought to be an indicator of nutritional stress. Eight sets of behavioral observations were made using focal and scan-sampling techniques at haulouts from 1995 to 1998 during three seasons (winter, spring, and summer). Counter to expectations, we found no significant differences between haulout populations in the time that lactating Steller sea lions spent at sea or on shore. This suggests that lactating sea lions did not have more difficulty capturing prey from winter through summer in the area of decline compared to where sea lion numbers increased. Lactating Steller sea lions in both regions did make longer foraging trips in winter than they did in spring and summer. These changes in foraging patterns among seasons were consistent among all years and sites. The proportion of time that immature Steller sea lions suckled declined through the spring to early summer, suggesting that sea lions began supplementing their milk diet with solid food in the spring. We did not observe any sea lions weaning during winter; rather, most appeared to wean at the start of the breeding season when they were 1 or 2 y old. Sea lions observed in southeast Alaska during the late 1990s while population growth was slowing suggest that most males weaned at 2 y and that about 50% of females weaned at 1 y and the remainder at 2 y. ******************************************************** Cooper, L.W.*, C.J. Ashjian, S.L. Smith, L.A. Codispoti, J.M. Grebmeier, R.G. Campbell, and E.B. Sherr. Rapid seasonal sea-ice retreat in the Arctic could be affecting Pacific walrus (Odobenus rosmarus divergens) recruitment. Aquatic Mammals 32(1):98-102. *Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN 37996, USA Under conditions of rapid sea-ice retreat and dissolution, we observed at least nine Pacific walrus calves separated from adult females in waters as deep as 3,000 m in July and August 2004 in the Canada Basin of the Arctic Ocean. Given limited sea surface visibility from the ship, we surmise that many additional calves may have been separated in the overall study area. These conditions appear to have been related to the transport of unusually warm (7° C) Bering Sea water into this area north of Alaska. Walruses invest considerable maternal resources while caring for calves on seasonally ice-covered continental shelves for periods of up to 2 y or more and only rarely separate from their young. Therefore, these observations indicate that the Pacific walrus population may be ill-adapted to rapid seasonal sea-ice retreat off Arctic continental shelves. ____________________________________________________________________________ Lanyon, J.M.*, K.. Newgrain, and T. Sahir Syah Alli. 2006. Estimation of water turnover rate in captive dugongs (Dugong dugon). Aquatic Mammals 32(1):103-108. *School of Integrative Biology, The University of Queensland, Brisbane, Queensland, 4072, Australia Water turnover rate was measured for two captive dugongs (Dugong dugon) using deuterated water. Body water content of 69.5% in a dugong was high compared to other marine mammals. A water turnover of 257.2 ml kg−1 day−1 measured in one dugong was almost twice as high as the highest rates measured in studies of captive West Indian manatees (Trichechus manatus) and was high compared to those measured in carnivorous marine mammals. The other dugong's estimated water turnover rate of 134 ml kg−1 day−1 was comparable to the highest rates in manatees. Two alternative explanations are offered for the high water turnover: (1) the incidence of mariposia or voluntary drinking of sea water by the dugong or (2) a metabolic rate that is significantly higher than predicted, based on its phylogeny. ************************************************************************ Pérez, M.J.*, F. Thomas, F. Uribe, M. Sepúlveda, M. Flores, and R. Moraga. 2006. Fin whales (Balaenoptera physalus) feeding on Euphausia mucronata in nearshore waters off north-central Chile Aquatic Mammals 32(1):109-113. *Eutropia, Centro de Investigacion de Aves y Mamíferos Marinos de Chile, Uno Poniente 960, Departmento 1102, Vina del Mar, Chile This paper reports the presence and feeding activity of fin whales (Balaenoptera physalus) during the austral summers of 2004 and 2005 in coastal waters near the Reserva Nacional Pinguino de Humboldt, north of Chile. The main prey item of the species was identified as the euphausiid Euphausia mucronata. The presence of B. physalus is associated with a high concentration of potential prey probably produced by an upwelling system that is frequently detected slightly south of the study area during summer. This information is a contribution to the knowledge of distribution, feeding behavior, and diet of B. physalus. Additionally, it constitutes the first record of a direct observation of feeding activity of B. physalus along the Chilean coast. ************************************************************************** Schusterman, R.J. 2006. Book review: Entanglements: the Intertwined Fates of Whales and Fishermen. Author: Tora Johnson. Aquatic Mammals 32(1):114-115. *Long Marine Laboratory, University of California at Santa Cruz, 100 Shaffer Road, Santa Cruz, CA 95060, USA *********************************************************************** Blomqvist, C. 2006. Book review: The Encyclopedia of Animal Behavior. Editor: Marc Bekoff. Aquatic Mammals 32(1):116-117. *Department of Physics, Chemistry, and Biology, University of Linkoping, SE-581 83 Linkoping, Sweden ------------------------------------------------------------------- -To submit a message to MARMAM, send it to: marmam@lists.uvic.ca -Please include your name and e-mail address in the body of the text of all submissions, and ensure your message has an appropriate subject heading (ie., not "Message for MARMAM") -Do not submit attached files or HTML/MIME messages. -To subscribe to MARMAM, go to lists.uvic.ca/mailman/listinfo/marmam -To contact the MARMAM editors, write to: marmamed@uvic.ca -MARMAM Editorial Policy & FAQ: http://whitelab.biology.dal.ca/marmam.htm