May 2007 - MARMAM - devlists.uvic.ca

Abstract: site fidelity, associations and movements of beaked whales in Hawaii
by Robin W Baird 21 May '07

21 May '07

New publication For pdf copies contact me or see http://www.blackwell-synergy.com/toc/mms/0/0 McSweeney, D.J., R.W. Baird, and S.D. Mahaffy. 2007. Site fidelity, associations and movements of Cuvier's (Ziphius cavirostris) and Blainville's (Mesoplodon densirostris) beaked whales off the island of Hawai'i. Marine Mammal Science 23: doi:10.1111/j.1748-7692.2007.00135.x ABSTRACT Although the Ziphiidae are the second-most speciose family of cetaceans, information on beaked whale species and populations has been limited by the difficulties in finding and approaching free-ranging individuals. Site fidelity, patterns of association and movements of two species, Cuvier's (Ziphius cavirostris) and Blainville's (Mesoplodon densirostris) beaked whales, were assessed using a 21-year photographic dataset from the west coast of the island of Hawai'i. Re-sightings of individuals of both species spanned 15-years, suggesting long-term site fidelity to the area. Long-term re-sightings were documented primarily from adult females of both species. Group sizes for both species were small and most groups had only a single adult male present. For Blainville's beaked whales, repeated associations between adult females and adult males were documented for all re-sightings of adult males over periods from 1-154 days. Among adult females, while repeated associations occurred up to 9 years apart, individuals were seen separately in intervening years. Individuals of both species seen on multiple occasions were typically documented in multiple months/seasons, suggesting they may use the study area throughout the year. Such long-term site-fidelity has implications both for potential population structure and for susceptibility of beaked whale populations to anthropogenic impacts. More information on this research can be found at www.cascadiaresearch.org/robin/hawaii.htm ======================================================== Robin W. Baird, Ph.D. Research Biologist Cascadia Research Collective 218 1/2 W. 4th Avenue Olympia, WA 98501 USA Phone 1-360-943-7325 Fax 1-360-943-7026 e-mail: rwbaird(a)cascadiaresearch.org www.cascadiaresearch.org/robin/robin.htm

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Postdoc Opportunity
by Mike Simpkins 21 May '07

21 May '07

Hello all, The U.S. Marine Mammal Commission and National Research Council announce a new program for Postdoctoral Awards (i.e., NRC Research Associateships). The Commission is an independent federal agency created by the Marine Mammal Protection Act, and is seeking creative, forward-looking scientists to address major challenges in marine mammal and marine ecosystem conservation. Opportunities exist to work at the interface between research, management, and policy decisions regarding critical marine mammal conservation issues. The Commission is seeking proposals for postdoctoral research on the following topics: -- The Effects of Climate Change on Arctic Marine Mammals -- Indicators of Ecosystem Health for Marine Ecosystems -- Marine Mammal Stock Assessment under the Marine Mammal Protection Act -- The Efficacy of Marine Protected Areas in Marine Mammal Conservation -- Co-management of Marine Mammals in Alaska -- Assessment of Cumulative Effects of Human Activities and Natural Stressors on Marine Mammals Interested candidates should submit resumes and pre-proposals in MS Word, WordPerfect, or Adobe PDF formats by 15 June 2007 to Michael A. Simpkins, Ph.D., Assistant Scientific Program Director, email address msimpkins(a)mmc.gov. A description of research topics and proposal submission procedures can be found at http://www.mmc.gov/NRCpostdoc.html. Research Associateship awards offer competitive stipends for 1 year with potential renewal for a total of 3 years maximum. The Commission anticipates selecting only one Research Associate. The primary duty location will be the Commissions office in Bethesda, MD. This program is open to foreign nationals as well as U.S. citizens. Further information regarding the NRC Research Associateship Program can be found at http://www.national-academies.org/rap.

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XVth Conference of the Society for Human Ecology
by Shirley Pacheco 21 May '07

21 May '07

Dear Colleagues, We are pleased to invite you to the XVth International Conference of the Society for Human Ecology to be held in Rio de Janeiro, Brazil, October 4-7, 2007. There will be a session about 'Contributions of fishermens local ecological knowledge and scientific research to marine mammal conservation' as detailed below. For more information about the conference and sessions, please check the link: http://www.societyforhumanecology.org/SHEXV.html SESSION I Indigenous / Local knowledge & Sustainability 1.6. Contributions of fishermens local ecological knowledge and scientific research to marine mammal conservation (S. Siciliano & S. Pacheco /ENSP/DENSP/FIOCRUZ & UNICAMP/FIFO/Inst. Terra & Mar, Brazil) Contact: sal(a)ensp.fiocruz.br or shirleypacheco(a)yahoo.com The local ecological knowledge (LEK) of fishermen has been applied in several conservation policies and practices related to fishery management around the world. Regarding marine mammals, studies addressing fishermens knowledge are still scarce. However, they have shown that in most cases their LEK is in high accordance with data obtained from scientific research. Most marine mammal species are poorly known. Some of these species are strongly affected by interactions with fishing gear, which makes fishermens LEK and cooperation greatly valuable for their conservation. For many threatened species time may be running out and since research on their biology are of long-term duration and generally expensive, the interface between fishermens LEK and scientific research should be widely explored to allow for expeditious decisions in favor of the protection and conservation of marine mammal species. Hope to see you there! Shirley Pacheco Shirley Pacheco de Souza Diretora Executiva - Instituto Terra & Mar Projeto SOS Mamíferos Marinhos PPG - Ecologia - UNICAMP Tel.: (12) 3862-1099 / 9144-6100 www.terraemar.org --------------------------------- Sick sense of humor? Visit Yahoo! TV's Comedy with an Edge to see what's on, when.

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Publication on Hawaiian Spinner Dolphins
by Sarah Courbis 20 May '07

20 May '07

> The following publication is now available. Abstract is below. > > Courbis, S. 2007. Effect of spinner dolphin presence on vessel and swimmer activity in Hawaiian bays. Tourism in Marine Environments. 4(1):1-14. > > EFFECT OF SPINNER DOLPHIN PRESENCE ON LEVEL OF > SWIMMER AND VESSEL ACTIVITY IN HAWAIIAN BAYS > SARAH COURBIS > Portland State University, Portland, OR 97207, USA > > Questions have been raised about the effects human activity in Hawai> '> ian bays has on dolphins. > Concerns about the effects of this activity have led the National Marine Fisheries Service to begin the > process of enacting regulations to reduce the impacts of swimmers and vessels on Hawaiian spinner > dolphins (Stenella longirostris). One step in evaluating potential effects is to determine if dolphin > presence attracts swimmers and vessels into bays. In this study, numbers of vessels and swimmers in > Kealake> '> akua, Honaunau, and Kauhako Bays were measured and related to spinner dolphin presence. > In Kauhako Bay, mean number of swimmers per scan sample was significantly higher when dolphins > were present, and in Honaunau Bay, mean number of kayaks per scan sample was significantly higher > when dolphins were present. In addition to measuring the relationship between dolphin presence and > vessel and swimmer presence, it is important to track vessel and swimmer numbers over time and to > determine patterns of use in individual bays. This establishes trends in human use of bays and allows > management on a more individual bay basis. During this study, Kealake> '> akua Bay experienced significantly > more vessel and swimmer activity than Kauhako Bay. Numbers of one- to three-person > kayaks, motorboats <6 m, and zodiacs were highest in Kealake> '> akua Bay. Numbers of swimmers > from shore were higher in Honaunau Bay than in Kauhako Bay. Overall, numbers of vessels and > swimmers in the bays were higher than in previous decades, and swimmers comprised the majority > human activity in the bays. > > Key words: Hawai> '> i; Vessel; Swimmer; Stenella longirostris; Spinner dolphin > > > Cheers! > Sarah > > Sarah Courbis > Ph.D. Candidate > Portland State University > sarahc(a)rogue.com >

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Abstracts - Aquatic Mammals (2007) - Special issue on hearing
by Dagmar Fertl 18 May '07

18 May '07

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. The EAAM and the Board of the Alliance of Marine Mammal Parks and Aquariums sponsor the journal. Aquatic Mammals accepts a wide variety of papers on the care, conservation, medicine, and science of marine mammals. Dr. Jeanette Thomas of Western Illinois University is the editor and Dr. Kathleen Dudzinski of Mystic Aquarium is the co-editor. These abstracts are posted as a courtesy to the Marmam editors and the sponsoring societies, as well as the managing editor of Aquatic Mammals. The latest issue of Aquatic Mammals is a special issue entitled: Electrophysiological Measurements of Hearing in Marine Mammals. The issue is divided into six parts: review, bottlenose dolphin, harbor porpoise, Pacific white-sided dolphin, new techniques, and pinnipeds, with a foreword by Michel André and Paul Nachtigall, the organizers of this special issue. The special issue is available on CD, as well as a limited number of hard copies. See the journal’s Web site for more details at: http://www.aquaticmammalsjournal.org <http://www.aquaticmammalsjournal.org/> . Please find below, the addresses (including email) of the authors to whom reprint requests and other inquiries should be directed. 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. dfertl(a)geo-marine.com <http://www.geo-marine.com/> http://www.geo-marine.com ********************** André, M.*, and P.E. Nachtigall. 2007. Electrophysiological measurements of hearing in marine mammals. Aquatic Mammals 33(1):1-5. *LAB, Laboratori d’Applicacions Bioacústiciques, Universitat Politècnica de Catalunya, Rambla Exposició s/n, 08800 Vilanova I la Geltrú, Barcelona, Spain. Direct author correspondence to : M. André at - Email: <mailto:Michel.Andre@upc.edu> Michel.Andre(a)upc.edu No abstract was provided, what follows is a summary. In March 2006, an international workshop was organized by Michel André and Paul Nachtigall and hosted by the European Cetacean Society during its 20th Conference in Gdynia Poland. The workshop brought together experts in the field of bioacoustics and hearing. The experts presented a summary of the ‘state-of-the-art’ of AEP studies on cetaceans and non-cetacean species as well as provided directions for future research. This special issue represents the output of the workshop. The article then briefly discusses the content of each article in the issue. ************* Nachtigall, P.E., T.A. Mooney, K.A. Taylor, and M.M.L. Yuen. 2007. Hearing and auditory evoked potential methods applied to odontocete cetaceans. Aquatic Mammals 33(1):6-13. *Marine Mammal Research Program, Hawaii Institute of Marine Biology, University of Hawaii, P.O. Box 1106, Kailua, HI 96734, USA. Email: <mailto:nachtiga@hawaii.edu> nachtiga(a)hawaii.edu Auditory evoked potential (AEP) procedures have been increasingly used to measure hearing processes in aquatic mammals. They have been demonstrated to be useful in measuring the audiograms of stranded animals like infant sperm whales (Physeter macrocephalus) and Risso’s dolphins (Grampus griseus). Modulation rate transfer functions (MRTF) demonstrating appropriate stimulus presentation rates are usually measured prior to recording audiograms with odontocetes. Measures comparing behavioral and AEP audiograms with the same animals have generally shown good correspondence between data gathered using the two procedures. AEPs and acoustic brainstem responses (ABRs) also have been used to measure hearing while an animal is actively echolocating. This technique of measuring the animal’s ability to hear its own outgoing signals, as well as the returning echoes, allows experimenters to develop a new understanding of the processes underlying echolocation. ******************* Supin, A.Ya.* and V.V. Popov. 2007. Improved techniques of evoked-potential audiometry in odontocetes. Aquatic Mammals 33(1):14-23. *Institute of Ecology and Evolution, Russian Academy of Sciences, 33 Leninksy Prospect, 119071 Moscow, Russia. Email: <mailto:alex_supin@sevin.ru> alex_supin(a)sevin.ru Efficiency of the auditory evoked-potential (AEP) method of audiometry in odontocetes can be markedly increased by the use of (1) stimulus parameters providing maximal AEP amplitude and (2) methods of better extraction of AEP from background noise. A train of short tone pips is a very effective stimulus that allows using the same analysis technique as the sinusoidally amplitude-modulated (SAM) stimulus, but provides much higher AEP amplitude. For AEP extraction from background noise, apart from a commonly used averaging method (mean-based extraction), mean-based extraction is very effective when the noise is not stationary and includes short, but big spikes or bursts. ************* Popov, V.V.*, A.Ya. Supin, M.G. Pletenko, M.B. Tarakanov, V.O. Klishin, T.N. Bulgakova, and E.I. Rosanova. 2007. Audiogram variability in normal bottlenose dolphins (Tursiops truncatus). Aquatic Mammals 33(1):24-33. Institute of Ecology and Evolution, Russian Academy of Sciences, 33 Leninksy Prospect, 119071 Moscow, Russia. Email: <mailto:popov_vl@sevin.ru> popov_vl(a)sevin.ru In odontocetes, underwater audiograms have been obtained mostly in one or two individuals in a species. A representative number of animals should be investigated to document variability. In the present study, an attempt has been made to estimate the audiogram mean and scatter among normal bottlenose dolphins (Tursiops truncatus). Measurements were made in dolphins captured in the wild and kept in captivity for three to five months, using auditory evoked potential (AEP) technique (envelope-following response [EFR]) to measure underwater hearing thresholds. Fourteen subjects, 11 males and 3 females, provisionally from 3 to 15 years old, were investigated. Hearing thresholds were measured at frequencies from 8 to 152 kHz with ¼-octave steps. All the subjects had qualitatively similar audiograms, except one. The averaged audiogram featured the best sensitivity (the threshold below 50 dB re 1 μPa) at 45 kHz. Thresholds rose slowly to lower frequencies (up to 65 dB at 8 kHz) and steeply at higher frequencies (up to 97 dB at 152 kHz). Inter-individual standard deviations varied, depending on frequency, from 4.4 to 11.7 dB, mostly not more than 10 dB. One animal featured a significant hearing loss with increased thresholds at frequencies above 54 kHz. An analytical formula for a standard audiogram is suggested based on these data. ************* Hernandez, E.N.*, S. Kuczaj, D.S. Houser, and J.J. Finneran. 2007. Middle- and long-latency auditory evoked potentials in bottlenose dolphins (Tursiops truncatus) resulting from frequent and oddball stimuli. Aquatic Mammals 33(1):34-42. *Department of Psychology, Box 5025, The University of Southern Mississippi, 118 College Drive, Hattiesburg, MS 39406, USA. Email: <mailto:erica.hernandez@yahoo.com> erica.hernandez(a)yahoo.com Middle- and long-latency auditory evoked potentials 9AEP) have not been extensively studied in marine mammals. Differences in longer latency potentials resulting from infrequent “oddball” stimuli inserted within a train of repeated, or “standard,” auditory stimuli can potentially be used to detect the discrimination ability of an individual. To investigate the characteristics of evoked responses resulting from the oddball paradigm, AEPs were recorded using 100-ms pure tones as stimuli and recording AEP epochs of 500 ms from two bottlenose dolphins (Tursiops truncatus). The P50 response to a 40-kHz pure tone was attenuated when that stimulus was repeated (the standard stimulus), with an 80% probability of occurrence. When a 30-kHz oddball tone was presented (20% probability of occurrence), however, the P50 response amplitude increased, indicating dishabituation to the novel stimulus. The attenuation of the P50 response to the standard tone was observed when the standard and oddball tones were reversed (30-kHz standard; 40-kHz oddball). The results demonstrated sensory gating, either habituating to a repeated stimulus (“gating out”) and/or dishabituating to a novel stimulus (“gating in”). The presence of one or both of these responses suggests that the P50 response to oddball stimuli has the potential to indicate discrimination of a particular set of auditory stimuli. ******************* Finneran, J.J.*, D.S. Houser, and C.E. Schlundt. 2007. Objective detection of bottlenose dolphin (Tursiops truncatus) steady-state auditory evoked potentials in response to AM/FM tones. Aquatic Mammals 33(1):43-54. *U.S. Navy Marine Mammal Program, Space and Naval Warfare Systems Center, San Diego, CA 92152, USA. Email: <mailto:james.finneran@navy.mil> james.finneran(a)navy.mil Auditory steady-state responses were measured in a bottlenose dolphin (Tursiops truncatus) and used to illustrative objective techniques to determine the presence and absence of a response. Experimental measurements were conducted under water in a quiet pool. Sound stimuli were pure tones that were both amplitude and frequency modulated. Evoked responses were recorded using noninvasive surface electrodes. Two frequency-domain techniques were used to assess the presence or absence of a response. The F test compares the evoked potential power at a single frequency (the amplitude modulation frequency) to the noise power averaged over adjacent frequencies. Magnitude-squared coherence (MSC) is a ratio of the signal power at a single frequency to the signal-plus-noise power and reflects the degree to which the system output is determined by the input. For the measurements here, both techniques provided identical results. Evoked potential thresholds based on the lowest detected response compared favorably to behavioral thresholds obtained in the same environment. ************* Lucke, K.*, P.A. Lepper, B. Hoeve, E. Everaarts, N. van Elk, and U. Siebert. 2007. Perception of low-frequency acoustic signals by a harbour porpoise (Phocoena phocoena) in the presence of simulated offshore wind turbine noise. Aquatic Mammals 33(1):55-68. *FTZ Westkueste, Christian-Albrechts-Universitaet zu Kiel, Buesum, Germany. Email: <mailto:lucke@ftz-west.uni-kiel.de> lucke(a)ftz-west.uni-kiel.de Using auditory evoked potential (AEP) methods, a study was conducted on a harbour porpoise (Phocoena phocoena) at the Dolfinarium Harderwijk in The Netherlands. The study measured the audible range of wind turbine sounds and their potential masking of wind turbine sounds and their potential masking effects on the acoustic perception of the animal. AEPs were evoked with two types of acoustic stimuli: (1) click-type signals and (2) amplitude-modulated signals. The masking noise resembling the underwater sound emissions of an operational wind turbine was simulated. At first, the animal’s hearing threshold was measured at frequencies between 0.7 and 16 kHz. Subsequently, these measurements were repeated at frequencies between 0.7 and 2.8 kHz in the presence of two different levels of masking noise. The resulting data show a masking effect of the simulated wind turbine sound at 128 dB re 1 μPa at 0.7, 1.0, and 2.0 kHz. This masking effect varied between 4.8 and 7.3 dB at those frequencies. No significant masking was measured at a masking level of 115 dB re 1 μPa. The available data indicate that the potential masking effect would be limited to short ranges in the open sea, but limitations exist to this conclusion and all estimates are based on existing turbine types, not taking into account future developments of larger and potentially noisier turbine types. ****************** Beedholm, K.*, and L.A. Miller. 2007. Automatic gain control in harbor porpoises (Phocoena phocoena)? Central versus peripheral mechanisms. Aquatic Mammals 33(1):69-75. *Institute of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark. Email: <mailto:beedholm@mail.dk> beedholm(a)mail.dk A previous study indicated no automatic gain control (AGC) in the auditory system of a harbor porpoise (Phocoena phocoena) as revealed by recording auditory evoked potentials to simulated echoes (Beedholm et al., 2006). The same harbor porpoise did change the rate and amplitude of its echolocation clicks during stationary echolocation when presented with an artificial target at a fixed delay. The animal spontaneously changed its click rate in such a way that emitted level (in dB, arbitrary reference) of a click decreased as the inter-click interval (ICI) decreased (click emission rate increases), according to a 14.5 log (ICI) function. The same relationship was found when the animal swam toward a target (a fish). It reduced the amplitude of its clicks as it approached the target with a -14 to -17 log r (best-fit), which is close to the expected -20 log r found in other studies. The combined results indicate an incomplete AGC working on the transmitter side and might be explained by constraints in the sound production apparatus that couple the sound amplitude to the click rate. ****************** Au, W.W.L.*, J.A. Thomas, and K.T. Ramirez. 2007. Characteristics of the auditory brainstem evoked potential of a Pacific white-sided dolphin (Lagenorhynchus obliquidens). Aquatic Mammals 33(1):76-84. *Marine Mammal Research Program, Hawaii Institute of Marine Biology, University of Hawaii, P.O. Box 1106, Kailua, HI 96734, USA. Email: <mailto:wau@hawaii.edu> wau(a)hawaii.edu Auditory brainstem responses (ABRs) of a Pacific white-sided dolphin (Lagenorhynchus obliquidens) in the presence of masking noise were measured at John G. Shedd Aquarium in Chicago. The dolphin was trained to wear suction cups with 1-cm diameter, gold-plated metallic electrodes typically used for human EEG measurements embedded in the cups. The animal was trained to station in a hoop, facing a sound projector 5 m away. ABR thresholds were obtained by progressively reducing the level of click stimuli, having peak frequencies of 8, 16, 32, 64, 80, and 100 kHz. The thresholds were obtained in the presence of broadband masking noise. The ABR waveforms were slightly different than for other odontocetes, having 7 to 8 waves present – the most for any odontocetes measured so far. The response latency of 1.3 to 1.5 ms is similar to those of other dolphins of approximately the same size. The peaks in the Fourier transform of the ABR waveform occurred at 650 and 1,200 Hz, very similar to the 600 to 650 and 1,100 to 1,200 Hz for Tursiops truncatus. The deepest null in the spectrum, which occurred at about 950 Hz, was much deeper than for the bottlenose dolphin. Masked ABR thresholds expressed in peak-to-peak values were between 38 and 56 dB above the rms values of the masking noise. ****************** Delory, E., J. del Rio, J. Castell, M. van der Schaar, and M. André. 2007. OdiSEA: An autonomous portable auditory screening unit for rapid assessment of hearing in cetaceans. Aquatic Mammals 33(1):85-92. *LAB, Laboratori d’Applicacions Bioacústiciques, Universitat Politècnica de Catalunya, Rambla Exposició s/n, 08800 Vilanova I la Geltrú, Barcelona, Spain. Direct author correspondence to : M. André at - Email: <mailto:Michel.Andre@upc.edu> Michel.Andre(a)upc.edu The screening of marine mammals’ auditory capabilities is a vital and delicate diagnosis elaboration process. A self-configurable, compact, and portable battery-operated screening tool is now available, named OdiSEA, which enables the collection of species-related auditory characteristics and a rapid diagnosis of hearing impairment, both in controlled and field situations such as rehabilitation facilities and at stranding sites, respectively. Acoustic stimulation is achieved with a calibrated piezoelectric ceramic that transduces sound either through a gel-filled suction cup or, more conventionally, from a few meters distance to the subject in a pool. System portability and the integration of a wideband (>150 kHz) auditory brainstem response (ABR) and multiple auditory steady-state response (multiple ASSR) evoked potentials system shortens diagnosis times significantly for both simple auditory tests and more detailed screening of auditory function. This unit should simplify and significantly accelerate the collection of audiograms in cetaceans. ****************** Taylor, K.A.*, P.E. Nachtigall, T.A. Mooney, A.Ya. Supin, and M.L. Yuen. 2007. A portable system for the evaluation of marine mammals’ auditory capabilities. Aquatic Mammals 33(1):93-99. *Marine Mammal Research Program, Hawaii Institute of Marine Biology, University of Hawaii, P.O. Box 1106, Kailua, HI 96734, USA. Email: <mailto:kristent@hawaii.edu> kristent(a)hawaii.edu We have created a portable system that is capable of measuring the hearing thresholds of marine mammals. It was designed for the purpose of testing the auditory capabilities for a wide range of marine mammal individuals and species. This system consists of multiple individual components, independently purchased or assembled. The major component of the system is a standard laptop computer with custom software that is able to both generate outgoing signals and acquire the corresponding brain measurements in response to those outgoing signals. The system has been, and still is, in an ongoing state of improvement and optimization with the goal of having a final system that could be used in nearly all field conditions. ****************** André, M.*, E. Delory, E. Degollada, J-M Alonos, J. del Rio, M. van Der Schaar, J.V. Castell, and M. Morell. 2007. Identifying cetacean hearing impairment at stranding sites. Aquatic Mammals 33(1):100-109. *LAB, Laboratori d’Applicacions Bioacústiciques, Universitat Politècnica de Catalunya, Rambla Exposició s/n, 08800 Vilanova I la Geltrú, Barcelona, Spain. Email: <mailto:Michel.Andre@upc.edu> Michel.Andre(a)upc.edu While noise is now considered a marine hazard that can directly affect cetaceans and induce a stranding, no clinical approach has yet introduced that detection of a possible hearing loss at a stranding site as a necessary practice. This can be explained by the lack of time when facing vital decisions for the animal’s welfare as well as the unavailability of reliable, lightweight, autonomous, and portable audiometry equipment. Herein, we correlate measured electrophysiological evidence of a permanent threshold shift (PTS) in a rehabilitated striped dolphin (Stenella coeruleoalba) that prevented its release, with the postmortem analysis of an abnormal dilation of the central nervous system ventricles that prevented the correct acoustic reception of the animal. We further propose to follow a five-minute auditory evoked potential (AEP) standard protocol of hearing measurements in-air on cetaceans at a stranding site that includes the stimulation of auditory brainstem responses (ABRs) with a single 4-μs broadband (>150 kHz) pulse at three decreasing levels (129, 117, and 105 dBpp re 1 μPa at 15 cm), which covers most of the cetaceans’ known maximum acoustic sensitivity and allow the immediate sensing of an individual’s hearing capability before any final clinical decision is taken. Houser, D.S.*, D.E. Crocker, C. Kastak, J. Mulsow, and J.J. Finneran. 2007. Auditory evoked potentials in northern elephant seals (Mirounga angustirostris). Aquatic Mammals 33(1):110-121. *BIOMEMETICA, 7951 Shantung Drive, Santee, CA 92071-3432, USA. Email: <mailto:biomimetica@cox.net> biomimetica(a)cox.net Auditory evoked potentials (AEPs) were investigated in northern elephant seals (Mirounga angustirostris) to characterize the responses elicitied by different acoustic stimulus types, examine temporal resolving capabilities, and evaluate the potential for using evoked responses to estimate hearing sensitivity. Clicks and tone pips were presented to individual seals to characterized evoked responses to broad- and narrowband stimuli. Tone pip trains and sinusoidally amplitude-modulated (SAM) tones were used to determine modulation rate transfer functions (MRTF) of the auditory system and to determine if the magnitude of the envelope-following response (EFR) relative to stimulus level can be used to estimate hearing thresholds. Click evoked responses were characterized by three early positive peaks (app. 2.6, 4.4, and 6.1 ms) and a dominant negative peak at 7.2 ms and had average amplitudes of 264 nV (peak-to-peak [pk-pk]) for a corresponding stimulus level of 126 dB re 20 μPa (pk-pk). The use of dissociative drugs for the immobilization of the seals showed no demonstrable effect on the latencies or amplitudes of the click evoked response. Both the rate following response (RFR) and EFR amplitudes were maximal when the stimulus repetition rate or the amplitude modulation rate, respectively, were <100 Hz. EFR amplitudes at the rate of amplitude modulation tracked near linearly with stimulus level. Thresholds for a 4-kHz, SAM tone were estimated to be 45 dB re 20 μPa. Thus, the recording of AEPs is a viable means of studying auditory processes in the northern elephant seal. ****************************** Mulsow, J.* and C. Reichmuth. 2007. Electrophysiological assessment of temporal resolution in pinnipeds. Aquatic Mammals 33(1):122-131. *Department of Ocean Sciences, Earth and Marine Sciences Building, University of California-Santa Cruz, Santa Cruz, CA 95060, USA. Email: <mailto:jmulsow@ucsc.edu> jmulsow(a)ucsc.edu Studies of auditory temporal processing in marine mammals have traditionally focused on the highly refined temporal capabilities of dolphins and other odontocete cetaceans. However, a recent electrophysiological investigation of manatee (Trichechus manatus) hearing has shown their temporal resolution to be better than expected, leading to speculation that enhanced temporal processing capabilities are adaptive for underwater sound localization. This study measured evoked responses from several California sea lions (Zalophus californianus), a harbor seal (Phoca vitulina), and a northern elephant seal (Mirounga angustirostris) to determine how well the auditory systems of these amphibious mammals resolve rhythmic stimuli. Trains of broadband clicks were presented in air at repetition rates from 125 to 1,500 s-1, and the averaged evoked responses elicited by those stimuli were recorded from the skin. Rate-following responses were detected in the sea lions at rates up to 1,000 s-1, with an upper limit of temporal resolution estimated at 875 to 1,000 s-1. This upper limit is better than previously anticipated and was further substantiated by limited testing with the harbor seal and northern elephant seal. While these findings might support an underwater sound localization hypothesis, measurements comparable to those of the pinnipeds were also obtained in a phylogenetically similar terrestrial mammal: a domestic dog (Canis familaris). It is therefore possible that increased temporal resolution in pinnipeds and other non-echolocating marine mammals is not a result of the evolutionary pressure of an aquatic environment. ****************************** Reichmuth, C.*, J. Mulsow, J.J. Finneran, D.S. Houser, and A.Ya. Supin. 2007. Measurement and response characteristics of auditory brainstem responses in pinnipeds. Aquatic Mammals 33(1):132-150. *Institute of Marine Sciences, Long Marine Laboratory, 100 Shaffer Road, University of California-Santa Cruz, Santa Cruz, CA 95060, USA. Email: <mailto:coll@ucsc.edu> coll(a)ucsc.edu The measurement of auditory evoked potentials (AEPs) has proven to be a useful tool for examining the auditory physiology of odontocete cetaceans and there is growing interest in applying this electrophysiological approach to study the hearing of other marine mammals. The aim of the current investigation was to examine some of the basic measurement and response characteristics of the auditory brainstem response (ABR) in pinnipeds. The subjects were California sea lions (Zalophus californianus), harbor seals (Phoca vitulina), and northern elephant seals (Mirounga angustirostris) there were awake, sedated, or anesthetized during in-air testing. Auditory stimuli were broadband clicks and Hanning-gated tone bursts there were presented binaurally in a direct field. The amplitude and waveform of the ABRs were evaluated as a function of subject sate, electrode type and position, analog bandpass filtering, stimulus presentation rate, and stimulus bandwidth. Results indicate that the ABRs were of highest amplitude when measured from subdermal electrodes arranged in a common reference configuration, with the cephalic electrode placed 2 to 4 cm forward of the ears on the dorsal midline of the head. The ABR waveforms were generally similar among the species tested, although the amplitude of the elephant seal ABR was much smaller than that of the other two species at similar stimulus levels. Bandpass filtering of the ABR resulted in improved signal-to-noise ratios but also caused reduction in response amplitude and distortion of the ABR waveform at high-pass settings above 65 Hz. Five-cycle tone bursts provided the best tradeoff between response amplitude and frequency specificity. The amplitude of ABRs evoked by clicks and tone bursts as a function of stimulus level was approximately linear for California sea lions and harbor seals over a range of app. 25 dB. Visually estimated thresholds for California sea lions were noise limited but were sensitive enough to show hearing loss in one older subject. These findings should inform future research efforts involving electrophysiological assessment of auditory function, hearing sensitivity, and noise i

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Positions Advertised - Tasmanian Govt Marine Conservation Section
by Drew.Lee＠dpiw.tas.gov.au 16 May '07

16 May '07

Two marine mammal positions are currently being advertised within the Tasmanian Governments Wildlife and Marine Conservation Section (DPIW). Advertisements shall appear in newspapers on 19 May 2007. Please find attached the positions advertised Project Leader, Marine Conservation and Marine Conservation Officer. Both Positions are now located on the Jobs Tasmania Website http://www.jobs.tas.gov.au Note: The closing dates for applications is June 1st, 2007. Applications can be sent to - Manager, Human Resources Management Branch, Department of Primary Industries and Water, GPO Box 44, Hobart, Tas, 7001, phone (03) 6233 6390, fax (03) 6233 2660, email Tammy.Lovell(a)dpiw.tas.gov.au. Project Leader, Marine Wildlife Conservation (702530) Applications Close:– Friday, 1 June 2007. Salary:– $59,604–$64,798 per annum. Professional Employees Award, Level 2. Permanent full-time. Location:– Hobart. Commencing salary within the above range will be determined in accordance with qualifications and previous relevant experience. Duties:– As a senior professional practitioner, provide authoritative wildlife and marine conservation professional support to the Section Head, Wildlife and Marine Conservation Section. Plan and implement marine mammal and bird conservation projects, provide research leadership and support on marine conservation issues relating to the full range of biodiversity conservation values in marine wildlife. Essential Requirements:– Satisfactory completion of an appropriate course of study at a recognised tertiary institution. Appropriate Course of Study:– For the purpose of the previous section, an appropriate course of study is a Degree in Science or an equivalent qualification from a recognised tertiary institution. Desirable Requirements:– A current motor vehicle driver’s licence. Work Place Level 2 First Aid Certificate or equivalent. Applications should quote position number, be marked Personal & Confidential and addressed as indicated. Enquiries to Melina Boerma, phone (03) 6233 6996, email Melina.Boerma(a)dpiw.tas.gov.au. Applications to Manager, Human Resources Management Branch, Department of Primary Industries and Water, GPO Box 44, Hobart, Tas, 7001, phone (03) 6233 6390, fax (03) 6233 2660, email Tammy.Lovell(a)dpiw.tas.gov.au. Marine Conservation Officer (701885) Applications Close:– Friday, 1 June 2007. Salary:– $38,801–$57,008 per annum. Professional Employees Award, Level 1. Fixed-Term full-time from asap for 12 months.. Location:– Hobart. Commencing salary within the above range will be determined in accordance with qualifications and previous relevant experience. Duties:– Participate in responses to marine issues, including monitoring of seals and seabirds and rescue of cetaceans in remote locations; conduct marine mammal research in remote locations; conduct necropsies on marine mammals; provide effective data management; provide marine vertebrate biodiversity management and develop and assist with delivery of an effective marine mammal biodiversity component in the Biodiversity Conservation Branch, especially to support the Princess Melikoff Trust Mammal Program. Essential Requirements:– Satisfactory completion of an appropriate course of study at a recognised tertiary institution. Appropriate Course of Study:– For the purpose of the previous section, an appropriate course of study is a Degree in Science or an equivalent qualification from a recognised tertiary institution. Desirable Requirements:– A current motor vehicle driver’s licence. Applications should quote position number, be marked Personal & Confidential and addressed as indicated. Enquiries to Drew Lee, phone (03) 6233 6013, email Drew.Lee(a)dpiw.tas.gov.au. Applications to Manager, Human Resources Management Branch, Department of Primary Industries and Water, GPO Box 44, Hobart, Tas, 7001, phone (03) 6233 6390, fax (03) 6233 2660, email Tammy.Lovell(a)dpiw.tas.gov.au.

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request your help in passing along this Poster Announcement
by JBrennan 16 May '07

16 May '07

Dear Colleague, Defenders of Wildlife is pleased to announce our upcoming symposium and we wish to invite interested participants to present a poster. May I ask for your assistance in distributing the following invitation to present a poster at our September symposium "Innovations in Wildlife Conservation: Reducing the Impact of Global Warming on America's Wildlife" to be held in Washington DC, on September 27th. Below is a shortened version of the announcement for use in newsletters and a pdf copy of the full announcement is attached for distribution or posting. The follow-up email contact and URL appear in the text. I am very grateful for your help, thanking you in advance. Jean Brennan *********************************************** Jean Brennan, PhD Conservation Scientist, Climate Change Defenders of Wildlife 1130 17th St. NW Washington, DC 20036-4604 Phone: 1-202-682-9400 ext 162 Web: www.defenders.org <http://www.defenders.org/> Email: jbrennan(a)defenders.org <mailto:jbrennan@defenders.org> Symposium Announcement and Call for Posters: Defenders of Wildlife announces "Innovations in Wildlife Conservation: Reducing the Impact of Global Warming on America's Wildlife," Sept. 27, 2007; 8am-6pm in Washington, DC. Speakers will explore the impacts of climate change on wildlife; the adaptation strategies to reduce those impacts; and policy responses necessary to ensure that wildlife species survive impacts of global warming over the next century. Science, Engineering, and Policy Innovators are invited to present posters demonstrating innovative approaches, strategies, and practices to enhance adaptation of wildlife to the impacts of global warming. Posters should broadly examine both the impacts as well as the types of tools, technologies, practices, and measures that should be considered if we are to meet the challenges of global warming. Symposium proceedings and poster abstracts, and recommendations for action, will be published. For more information and to submit an abstract please visit: www.defenders.org/innovations/symposium2007 . Questions may be addressed to: poster(a)defenders.org

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Atypical association
by Jeremy KISZKA 16 May '07

16 May '07

Sorry for cross-posting! Dear all We observed an atypical inter-specific association in the Comoros archipelago, in the Mozambique Channel (south-west Indian Ocean), of an adult female Indo-Pacific humpback dolphin (coastal species) and a spinner dolphin calf (mostly oceanic in this area). Both individuals are generally associated with other humpack dolphins. According to local dolphin watching operators, this association is observed for at least six months (the animal was newborn). First observations reported a probable hybrid (with a Tursiops, already observed in this area), but there are evidences that the calf is definitely a spinner. I would ask if similar cases have been observed in cetaceans and even in other mammals such as primates. Many thanks, Jeremy jeremy.kiszka(a)wanadoo.fr _________________________________________ Jeremy KISZKA (MSc, PhD cand.) CRELA (Centre de Recherche sur les Ecosystèmes Littoraux Anthropisés). UMR 6217 CNRS-IFREMER-Université de la Rochelle Avenue Michel Crépeau, 17071, La Rochelle, France. & Direction de l'Environnement et Développement Durable, Collectivité Départementale de Mayotte, BP 101, 97600 Mamoudzou, Mayotte. Tel. (bureau): (+261)02.69.64.99.17 GSM: 06.39.69.53.53

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Baleen whale (humpback?) accidentally "swallowing" a boat
by Klaus Barthelmess 16 May '07

16 May '07

For my ongoing study on the cultural history of human-cetacean relations, to be published in book form, I envision an chapter called "'Can whales do that?' Fact and fiction in popular whale lore". Recently I came across an old report of a baleen whale, perhaps a launch-feeding humpback, accidentally "swallowing" a boat. It is said to have occurred off Ireland on 28 November 1829 and is reported in the Massachusetts Yeoman and Worcester Saturday Journal and Advertiser of 6 February 1830, page 4, and reads thus: "A Boat's Crew Swallowed by a Whale. - A correspondent of the Dublin Morning Register, under date of Benn Green, Danally, Nov. 30, says - "I have to report a most awful and unparalleled event, which took place in Inver Bay on Saturday last. ((Which would make it the 28 November 1829; KB)) Five men, in a yawl, were in pursuit of a shoal of sprats, for bait, with hand loops, when a whale following the shoal, with open jaws came in contact with the yawl (broadside to.) Feeling the yawl, the monster closed its jaws, and crushed it in pieces, with the exception of the two ends, in one of which was a young lad, in the act of putting out his loop. He was the only one out of five that escaped. One man was found crushed, and fastened to a piece of the floating wreck. A bunch of hair, from the gills of the whale ((bristles of baleen; KB)) fastened in a shiver of the wreck, confirms that the boat was destroyed in the way described, and in the way which those on shore and those in the boats agree in attesting."" Well, is such an accident imaginable? I recall someone (Judy Whitehead?) at a conference many years ago telling how a breaching humpback once landed on her boat. But I'm wondering if anyone can confirm - or give reasons why to dispute - accidents with baleen whales of the type described in the old news article. Thanks and kindest regards Klaus Barthelmess Cologne, Germany

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oarfish-cetacean interactions
by Tyson Roberts 15 May '07

15 May '07

Dear Marine Mammal Discussion group members, I have recently completed but not yet published a worldwide monograph on the oceanic fishes known as oarfishes (genus Regalecus). This work includes anextensive review and original observations on the systematics, biology, ecology, and distribution. Two species of Regalecus are recognized. They occur widely in the Pacific, Atlantic, and apparently also the Indian Oceans. Information on predators of Regalecus is remarkedly sparse and poorly documented. While small oarfish (usually far less than a meter long) are eaten by lancet-fish and tunas, remarkedly little is known concerning predators on large Regalecus (from 1-8 m long). The widely held belief that large Regalecus are commonly preyed upon by sharks is unsubstantiated and almost certainly false (any scientific observations of oarfish actually being eaten by sharks would be extremely welcome). Moreover, there seems to be no published information on other potential large oarfish predators, including squids and cetaceans. I do not know of a single published account of any whale or dolphin species feeding on oarfish. Information about cetacean or any other other predators on Regalecus would be extremely welcome. Tyson R. Roberts Send instant messages to your online friends http://uk.messenger.yahoo.com

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