Contact details Sanna Kuningas: 07547 004367 Marjolaine Caillat: 0796 250 5758 Map Conference Schedule Wednesday 26
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The Society for Marine Mammalogy UK Student Chapter Meeting 2011, University of St Andrews 
Contact details Sanna Kuningas: 07547 004367 Marjolaine Caillat: 0796 250 5758 Map
Conference Schedule
Abstracts Variation in the Maternal Behaviour of Grey Seals (Halichoerus grypus): The Good the Bad and the Ugly Robinson, K.J1*, Pomeroy, P.P1, Hazon, N1, & Twiss, S.D2 1NERC Sea Mammal Research Unit, Scottish Oceans Institute, East Sands, University of St. Andrews, Fife, KY16 8LB, UK 2School of Biological and Biomedical Sciences, Durham University, South Road, Durham, DH1 3LE, UK *Email: kjr33@st-andrews.ac.uk Female Grey Seals (Halichoerus grypus) spend only 18 days with their dependant pups before weaning them and returning to the sea. The maternal care invested in a pup during this time is a major factor in the likelihood of its survival both to weaning and in the first year of life. Yet females of this species show remarkable variation in the quality of maternal behaviour they express to both their own, and non-filial pups. To investigate the potential causes of such disparities, maternal behaviour on the North Rona breeding colony was observed over two seasons (2009/2010). Of 39 females studied, 11 exhibited apparently deleterious behaviours. These behaviours ranged from those that caused pup injury or death to those that should cost the female substantial energetic resources for no apparent gain. To understand this variation, the endocrinological and neurobiological mechanisms underlying maternal behaviour and mother/offspring bonding are explored. By looking at how maternal behaviour should manifest, and considering the environmental conditions on a grey seal colony, explanations for such variation can be formulated and then tested. An introduction to the diurnal behavioral patterns of the Gulf of Maine Humpback Whales Jennifer Allen1 1Ocean Alliance, Gloucester, MA, USA Humpback whales often behave unpredictably. Learning about their behavioral patterns has more than just commercial value; the more that is known about a species, the more effectively it can be protected. A survey of the Gulf of Maine humpback whale population was conducted from several whale watch vessels between 2002 and 2009 to examine the potential relationship between the frequency of observed behaviors and the time of day at which they were performed. Of the 12 observed behaviors, 6 occurred more often in the morning, and 1 occurred more often in the afternoon (Student’s t-test, p<0.05). Whether or not these trends are biologically significant remains unclear. Behaviors were also looked at in terms of age class to determine a potential relationship. While there was a lack of feeding behaviors observed in calves, overall the results were did not determine a significant pattern. It is recommended that this study be done in a more intensive manner with more focused data collection methods. Diurnal patterns have not been studied in humpback whale populations, and this study provides a good baseline of information for future studies. When seals attack: Aggression in grey seals outside of the breeding season Sarah Marley Satellite telemetry studies have implied that haul out sites are important resources for grey seals (Halichoerus grypus). Some other pinniped species have been found to form dominance rankings on haul-out sites outside of the breeding season, which minimises aggression and competition for space. Little is known of grey seals’ social behaviour during this part of their life cycle, however the species has been observed to form dominance hierarchies on their breeding sites. This project aimed to describe the context of aggressive behaviour in grey seals outside the breeding season, and consequently discuss the possibility of a dominance hierarchy existing on such haul-out sites. During summer 2009, c.53hrs of behavioural data were collected from Abertay Sands, Scotland. No correlation was found between aggressive interaction frequency and group size. However, a relationship existed between interaction frequency and both tidal state and time after first haul out, with aggression being most frequent in the first 30mins of group formation. Agonistic behaviour generally resulted from space invasion or incidental contact; yet winners of conflict were never observed ‘taking over’ space vacated by losers. The nature of aggressive interactions varied depending upon the participants. The majority of same-sex interactions occurred between equally-sized opponents, with the initiator typically winning such conflict; if participants were of different sizes, the larger animal usually won. However, mixed-sex interactions generally involved unequally-sized participants. In these interactions, the female was more likely to win, regardless of the size of the male or who initiated the interaction. Aggression on grey seal haul outs occurs independently of space availability or seal density, and instead appears to be at its highest in the first thirty minutes of group formation. Although strong evidence for the existence of a dominance hierarchy outside the breeding season is lacking, data suggest that dominance relationships may exist both between and within the sexes.
René Swift1 1Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews, Fife KY16 8LB, U.K. Can we identify misidentified whistling cetacean species? Marjolaine Caillat1 1Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews, Fife KY16 8LB, U.K. Marine mammals spend most of their time under water. The chance of detecting them visually can decrease dramatically as a function of the species characteristics or environmental conditions. To communicate, to find their food or to navigate marine mammals produce a large variety of sounds which, depending on the species, can travel from few meters up to hundreds of kilometers. Marine mammal surveys have been improved by the use of passive acoustic monitoring. Acoustic detection has the advantage of being less weather dependent and does not require the continuous presence of an observer. However, it is often difficult to identify the species that is vocalizing during the recording. Automatic classification methods have been developed to solve this problem. Because of the variety of sounds produced by marine mammals, it is not possible to have a perfect automatic classifier and hence to classify all detected sounds correctly. If we want to use this acoustic data to estimate relative or absolute abundance of the species within the survey area, this uncertainty generated by the miss-classified detections must be included in density estimation models. Here, we use a Bayesian approach to study the impact of the uncertainty generated by the miss-classified detections on the estimation of the true number of detections. Hidden Markov Models for automatic classification of humpback whales’ songs. F. Pace1, P. White1 & O. Adam2 1 Institute of Sound and Vibration Research, University of Southampton, UK 2 Université Pierre et Marie Curie, Paris 6 Jussieu, France Humpback whales songs have been widely investigated in the past few decades. This study proposes a new approach for the classification of the calls detected in the songs with the use of Hidden Markov Models (HMMs). HMMs have been used once before for such task but with an unsupervised algorithm with promising results. Here HMMs were trained and two models were employed to classify the calls into their component units and subunits. The results showed that classification of humpback whale songs from one year to another is possible even with limited training. The classification is fully automated apart from the labelling of the training set and the input of the initial HMM number. The subunit model performed better with less user input, due its flexibility. Having achieved promising results, future work will deal with reducing the training set to a minimum whilst maintaining high classification accuracy to reduce the computational effort and human input. Harbour porpoise spatial distribution in relation to small scale physical and hydrodynamic controls in SW Cornwall Alice Jones1 1National Oceanography Centre, Southampton The physical marine environment has a strong influence on marine biology through bio‐physical coupling. Research indicates that apex marine predators are often attracted to areas associated with topographic or oceanographic features such as headlands, reefs or frontal systems. This study aims to improve the understanding of this relationship by analysing data on the fine scale distribution patterns of harbour porpoises (Phocoena phocoena) in relation to topographic and tidal features in southwest Cornwall. The study investigates the physical controls on spatio‐temporal patterns in harbour porpoise (phocoena phocoena) surface sightings collected in an effort‐based visual monitoring survey in southwest Cornwall. The survey is undertaken at a coastal watchpoint overlooking a locally unique topographic feature, the Runnelstone Reef, for which high resolution bathymetry data is available. Spatial analysis of sightings data has been undertaken in order to better constrain the effect of small scale topographic features within the study area on the local harbour porpoise activity. Results indicate the sightings are clustered in the region of identifiable topographic features. Based on these initial findings, locations were determined for three moored passive acoustic monitoring devices (CPODs) which were deployed during the 2010 season. The CPODs collected further data on sub‐surface and nocturnal porpoise activity and distribution. Results of preliminary CPOD data analysis will be presented with relation to concurrent visual observations, day/night activity and tidal flow. Investigating variation in whistle structure between three parapatric bottlenose dolphin communities in Irish coastal waters Anneli Englund1, Simon Ingram2 &Emer Rogan1 1School of Biological, Earth & Environmental Sciences, University College Cork, Distillery Fields, North Mall, Cork, Ireland 2School of Marine Conservation, School of Marine Sciences and Engineering, University of Plymouth, Drake Circus, Plymouth, Devon, PD4 8AA, United Kingdom Bottlenose dolphins (Tursiops truncatus) show evidence of community structuring in Irish coastal waters. We investigate how this might be reflected in their vocal repertoire. Recordings were made from three communities: a seasonally resident population of 140 in the Shannon Estuary (mid-west coast), an apparently separate but adjacent and mobile community in Connemara (north-west coast) numbering 170 and a group of six individuals regularly using Cork Harbour (south coast) since 2007. The Shannon population appears genetically isolated from adjacent coastal areas, except regarding the group in Cork, indicating ongoing gene flow or recent dispersal between these areas. Photo–identification have confirmed that coastally ranging dolphins, including Connemara animals have large home ranges, while estuarine animals are only observed close to the Shannon. A total of 3,012 whistles were recorded at a sampling rate of 96kHz. 140 good quality whistles were randomly selected from each community and frequency contours extracted in Matlab. Six acoustic parameters were calculated and run through discriminant function analysis, resulting in accurate prediction of sampling community in 48.8% of the cases. Whistle types were shared between communities, illustrated through a neural network approach (ARTwarp) where whistles were classified into categories based on a vigilance factor (Deecke and Janik, 2006). At 96% vigilance, 420 whistles generated 185 categories of which 29% contained whistles from more than one community and 9% contained whistles from all three communities. ANOVA revealed variation between the communities in maximum, minimum, start and end frequency (log transformed). Post-hoc analysis indicated significant differences in all four parameters between Shannon and Connemara and between Cork and Connemara while minimum frequency was the only parameter significantly different between Shannon and Cork. The results indicate a greater similarity in whistle characteristics between more closely related communities demonstrating that relatedness may play an important role in divergence of vocalisation behaviour. Are marine protected areas (MPA) free of acoustic pollution? Case examples of noise from fishing and shipping activities in deep-water areas of the Mediterranean Lucía Martina Martín 1,2, Ana Tejedor 3, Albert López-Larrosa 4 and Natacha Aguilar1,5 1BIOECOMAC, La Laguna University, Tenerife, Canary Islands, Spain 2SMRU, Sea Mammal Research Unit, Gatty Marine Laboratory, University of St. Andrews, U.K. 3ALNITAK, Nalon 16. E-28240 Hoyo de Manzanares, Madrid, Spain 4Projecte NINAM, Roses, Girona, Spain 5Leigh Marine Laboratory, University of Auckland, New Zealand Cetaceans and other marine fauna use sound for vital functions such as communication, foraging and predator detection. Signals mediating these functions can be masked by increased levels of ambient noise. Therefore, buffering from acoustic pollution should be considered when designing MPA. Some sources of noise can increase background noise levels at large distances. This is most relevant for “chronic” activities occurring repeatedly in an area. Here we analyze two chronic sources of anthropogenic noise in some areas of the Mediterranean: bottom-trawling fishing and shipping lines. The study was performed within the context of the EU project LIFE+INDEMARES and we present case examples showing that noise produced outside MPA has the potential to affect marine life within the borders of MPA. Recordings were taken in two key areas for the Natura2000Network: Cap de Creus (Catalunya) and Alboran Sea. Point sound samples (30min) were gathered with a calibrated hydrophone (Reson TC4032). In Cap de Creus, broadband (100Hz-40kHz) noise levels increased by 15dB re 1µPaRMS in recordings performed at 0.5, 1.2 and 1.4km from trawling boats over recordings in the same area with no boats in a 6nm radius. Under the conservative assumptions of the closest boat dominating the noise signature and spherical sound transmission, the radius at which trawling noise exceeds usual background noise in this area is around 3km. The Alboran Sea is crossed by over 25% of the World’s shipping activity, with the main shipping line located north of the Alboran Island. We performed recordings following a north-south transect and low frequency noise (<150Hz) broadband sound levels in the most northern point (18km from Alboran Is.) exceeded in 10dB re 1µPaRMS the levels in the other recordings. This examples point to the need of gathering long-term datasets of acoustic levels in MPA and create “acoustic buffer zones” around them. Investigating the influence of small scale, tidal topographic fronts on the distribution of marine megavertebrates Sophia Butler-Cowdry1 1National Oceanography Centre, Southampton Near shore foraging locations of marine megavertebrates may be limited both spatially and temporally. Previous studies have shown that marine mammals and seabirds not only demonstrate preferential use of a small number of locations, but that these are influenced by a particular range of tidal conditions and oceanographic variables. Oceanic fronts exert a strong, bottom up control on marine ecosystems from the distribution of phytoplankton and zooplankton blooms, to fish shoaling and the resultant concentrations of megavertebrates. These prey aggregations not only affect the distribution of marine megavertebrates but also associated commercial fishing activities. Tidal fronts formed at the interface with distinct topographic features may specifically be further influencing the distribution of a range of marine species, which is the focus of this PhD. By concentrating effort based field monitoring at selected locations and utilising high resolution (<5 m) multi beam bathymetry data, the PhD aims to constrain, identify and better explain the spatio temporal distributions of marine megavertebrates at a fine scale. Data from passive acoustic monitoring stations and in situ zooplankton sampling will also be collected. The environmental data together with the biological data from all the target sites will be compiled into a GIS and analysed using various statistical techniques, including GLMs and GAMs, as appropriate. The use of predictive models in combination with GIS is a powerful tool in ecology that will contribute to our understanding of the complex relationships through the trophic levels. A deep scientific and political understanding of these interactions is of course vital for establishing effective conservation measures and appropriate management of the marine environment. In the face of ever increasing pressures in this domain, from the recreational to the renewable energy sector, good science is an urgent pre requisite. Population dynamics of killer whales in northern Norway Sanna Kuningas1 1Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews, Fife KY16 8LB, U.K. Long-term photo-identification study of killer whales (Orcinus orca) in northern Norway initiated in 1986, once their prey the Norwegian spring-spawning herring (Clupea harengus) started to winter in a fjord system above the Arctic Circle. The aim of this work was to estimate population size, survival rates and temporary emigration rates of identifiable individuals in this killer whale population using photo-identification and mark-recapture techniques with data collected during October-January 1986-2003. Mark-recapture analysis was done with program MARK. Total population size was estimated to be highest in year 2003: 731 individuals (SE = 136, 95% CI = 509-1051) by M(th)Chao model. Apparent constant survival (CJS) for adult males and adult females were estimated as 0.967 (SE = 0.0062) and 0.968 (SE = 0.0081), respectively. Estimate of survival with blocks of time show an increase in mortality through the 18 years. Pollock´s robust design results confirmed temporary emigration occurring from the main wintertime area and this movement to be random. This work presents a new description of northern Norwegian killer whale population parameters and adds up to the knowledge of this species globally. Investigating the influence of tidal mixing fronts on marine megavertebrates off southwest UK Lavinia Suberg1 1National Oceanography Centre, Southampton Tidal mixing fronts are interfaces between water masses of different density or temperature, typically separating coastal mixed and offshore stratified waters. Frontal zones are biological hotspots that are characterized by enhanced primary production and accumulations of zooplankton and fish; they therefore represent important foraging areas for marine top predators, e.g. cetaceans and seabirds. The location, intensity and persistence of tidal mixing fronts controls the distribution of organisms across all trophic levels at a variety of spatio-temporal scales. Understanding these relationships is essential in deciphering pelagic ecosystem dynamics, and is vital for effective spatial conservation planning, e.g. establishment of MPA’s. This PhD project will investigate environmental factors controlling the distribution of tidal mixing fronts (e.g. SST, tide, weather) on different time scales (weekly to inter-annually) and in turn, how changes in frontal characteristics affect the ecosystem at different trophic levels. This will be achieved by comparing archival remote sensing, CPR and megavertebrate observation data across selected fronts off southwest UK, as well as collecting real-time monitoring and observation data from these fronts. The results will provide a better understanding of spatio-temporal distributions of cetaceans and other megavertebrates off southwest UK, and may also provide an important evidence base highlighting the importance of tidal mixing fronts as conservation features. Demography and conservation status of Pacific white-sided dolphins in British Columbia, Canada Erin Ashe1* 1Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews, Fife KY16 8LB, U.K. *Email: ea84@st-andrews.ac.uk Pacific white-sided dolphins are known from archaeological evidence to have inhabited inshore coastal waters of British Columbia (BC), Canada for centuries, but the species has been virtually absent from the region for much of the 20th century. The dolphins “re-colonised” the area in the 1980s, when they started to appear in large, acrobatic, and conspicuous groups. The conservation status of Pacific white-sided dolphins has not been assessed in Canada since 1990, and there is a need for science to re-evaluate the status of this species. The overall aim of the research project is to estimate abundance and survivorship of Pacific white-sided dolphins using photo-identification, by following a sample of naturally marked individuals through time in a study area in inshore waters that is accessible year-round. A photo-identification study was initiated in 1989 that now includes more than 1,000 individually recognisable dolphins. For the period between 1989 and 2005, I estimated a population rate of change of 1.06 (SE=0.099) using a Pradel model. It is not clear whether this 6% annual rate of increase true biological population growth, immigration, or both. Interestingly, newborn calves were never seen by researchers or whalewatchers in the study area between 1984 and 1995. Calves were seen rarely between 1995 and 1998, but newborn calves are now seen regularly. Abundance and survival rate will be estimated using additional mark-recapture methods that are robust to movement into and out of the study area. The next phase builds on a 20-year longitudinal photo-identification database by adding photographs collected since 2005. Pacific white-sided dolphin population structure will be assessed by exploring movement patterns, acoustic patterns, and possibly genetic information. The potential impact of killer whale predation on natural mortality rates will also be evaluated. The seasonal movements and dynamics of migrating humpback whales (Megaptera novaeangliae) off the east coast of Africa, between Plettenberg Bay, South Africa and the southwest Indian Ocean breeding grounds Aaron Banks1 1Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews, Fife KY16 8LB, U.K. The partitioning of the Southwest Indian Ocean humpback whale breeding grounds (Area C), recommended by the IWC, into three sub-regions (C1, C2 and C3) is linked to the assumption of three different migration routes conveying whales to and from area C. This raises important questions about which sub-region(s) are associated with the humpback whales seen in transit past Plettenberg bay in South Africa. The current assumption is that these whales are C1 (Mozambique) animals. Sighting data, tail fluke and dorsal fin images and biopsy samples were collected in Plettenberg Bay, South Africa during 2005 to 2008; Bazaruto Archipelago, Mozambique 2007 and Ponta Mamoli, Mozambique in 2009. 708 hours of sea time resulted in 324 humpback whale sightings being made. 330 tail flukes, 570 left dorsal fin and 569 right dorsal fin were collected including 47 skin samples. Using tail flukes, eight individuals from Plettenberg Bay have been re-sighted. Of these, five were between year matches in Plettenberg Bay, one within year match in Plettenberg Bay and two between year matches between Plettenberg Bay and Ponta Mamoli, Mozambique. Images were also compared to South West Africa (B2) and the IWC Antarctic catalogue (Area III & IV) to determine any interchange with and between breeding grounds and to determine links to feeding grounds. Boat-based sighting data will provide baseline data on encounter rates for the migration route and C1 breeding ground. Genetic analysis will be used to determine the genetic identity and variation with the population of humpback whales observed between South Africa and Mozambique. Insights into the function of acoustic signals produced by Icelandic killer whales (Orcinus orca) from sound pressure levels Samarra, F. I. P.1 1Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews, Fife KY16 8LB, U.K. Fish-eating killer whales (Orcinus orca) in Iceland are vocally active during feeding, producing calls, whistles, and low-frequency ‘herding’ calls. Recently, these whales were shown to also produce high frequency whistles, with fundamental frequencies entirely above 17 kHz. The sounds produced by killer whales could function in short range communication within the feeding group, long-range communication with animals in other groups, and/or to manipulate prey. Here, these possible functions of calls, high-frequency whistles, and ‘herding’ calls were investigated by comparing their source sound pressure levels. The range to signallers was measured using time-of-arrival-differences on a calibrated 4-element vertical hydrophone array. A total of ~19 hours of recordings were collected over 5 days in July 2008 and 10 days in July 2009 in Vestmannaeyjar, Iceland. A total of 7,203 calls, 92 herding calls and 419 high frequency whistles were identified but source levels were only calculated for signals of high signal to noise ratio localised near the hydrophone array. Because the orientation of signallers relative to the hydrophone array was unknown only apparent source levels (ASL) were calculated. The source levels of the three sound types was found to overlap, but high frequency whistles had the lowest median ASL, followed by stereotyped calls and herding calls. This suggests diverse functions for the sound types. High frequency whistles are most likely used in short range communication, as their source level and high frequency suggest they would be detected over shorter distances. Stereotyped calls have characteristics more suitable for longer range communication, whereas the source levels of the herding call support its proposed function to manipulate prey. Vocal matching in the Bottlenose Dolphin Stephanie L. King1 & Vincent M. Janik1 1Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews, Fife KY16 8LB, U.K. Vocal matching is a powerful interactive tool used by a select number of animals. By matching the signal that was given by a caller within a short time window, the matching animal can direct its communication at the caller. This acoustic matching of call types in dyadic vocal exchanges has been observed in numerous taxa. The most prominent of these include the passerines and odontocetes. In songbirds vocal matching is a signal of aggressive intent. In contrast the functional significance of matching events in bottlenose dolphins remains unclear. Bottlenose dolphins use individually-distinctive signature whistles. Signature whistle matching has been previously reported in this species. We conducted an interactive playback experiment with captive bottlenose dolphins. We addressed the function of signature whistle matching by identifying how an animal responds to being vocally matched and to isolate the effects of vocal matching upon conspecific behaviour. Upon an animal producing its signature whistle we (1) played back its own signature whistle to it thereby vocally matching the animal; or (2) played back an unfamiliar signature whistle which acted as a control. Animals always responded to being matched by calling back, which was significantly different to the control (GLM, df=35, p<0.0001). There was no evidence vocal matching was an aggressive signal in this species. Instead bottlenose dolphins may match one another’s individually-distinctive call types to mediate social relationships and facilitate localization of conspecifics. A comparison of the discrete call repertoires of Northeast Atlantic killer whales (Orcinus orca) A-V. Duc1,2, F.I.P. Samarra2, V.B. Deecke2,3 & P.J.O. Miller2 1Uppsala University, 752 36 Uppsala, Sweden 2Sea Mammal Research Unit, Scottish Oceans Institute, University of St. Andrews, St. Andrews, Fife KY16 8LB, United Kingdom 3Cetacean Research Laboratory, Vancouver Aquarium, P.O. Box 3232, Vancouver, British Columbia V6B 3X8, Canada It has been previously suggested that Icelandic and Norwegian herring-eating killer whales have been in contact in the past, when the herring stocks both populations feed upon shared the same feeding grounds. Although photo-identification data suggest that the Icelandic and the Norwegian herring-feeding killer whales are not currently in contact, behavioural studies have shown that they use similar foraging and feeding strategies. In this study we are building a catalogue of the call types of the Icelandic population from ~64 hours of underwater recordings off two locations in Southwest Iceland. The recordings were made using sound recording tags attached using suction cups (Dtags), a 4-element vertical hydrophone array and a 2-element towed hydrophone array. Here, we compare the call types of the Southwest Icelandic catalogue to the previously described vocal repertoire of killer whales from East Iceland. Then we compare these sounds with calls of killer whales from Norway and Shetland which have been documented in previous studies or recorded by ourselves. Similarities between these repertoires may reflect the ecological similarities of different populations of herring-feeding killer whales as well as genetic and/or past social relationships. Comparison of the songs of smaller and larger humpback whales (Megaptera novaeangliae) Elisa Girola & Jim Darling The size of an animal could affect sound production in two ways: it could determine the characteristics of the sound production mechanism, and thus the characteristics of the sounds produced; it is usually related to the age of the animal, and could therefore reflect different stages of a vocal ontogeny process. Main aims of this project are to provide an objective description and classification of units, that constitute the basic components of humpback whale songs; to investigate the presence of acoustic cues to body size these units may contain; and to assess the presence of differences in song composition and structure that could be related to different levels of vocal development. Data were collected in the winters of 2000 to 2003, in the Hawaiian Islands. A total of 25 singers were recorded and measured. For each year four whales were selected, each of them representing a size class. First, sounds characteristics, such as: duration, noisiness, fundamental frequency, waveforms, spectrograms, and spectra profile; were analysed in order to identify distinguishing features and grouping criteria. Then, recordings from whales of different size classes were compared, considering both units characteristics, and songs characteristics. 33 different unit types were identified and classified into four categories: low-, mid- and high-frequency harmonic sounds, and broadband sounds with a harmonic component. Sound characteristics were distinctive for each singer and in some cases they correlated with body size, while song characteristics didn’t show consistent differences associated with this parameter. These results support the hypothesis that humpback whales sound production mechanism is similar to that found in most terrestrial mammals, and thus the same theories could be applied to study their vocalizations. Different individuals can be distinguished from the sounds they produce. All whales in our sample have a completely developed song, and most likely have reached vocal maturity. Fine-scale patterns of North Pacific right whale (Eubalaena japonica) call production Carter Esch1 1Woods Hole Oceanographic Institution, Biology Department The eastern stock of North Pacific right whales (NPRW) is critically endangered, and is currently the focus of intensive monitoring efforts in the southeast Bering Sea. Passive acoustic monitoring has proven to be a useful technique for detecting right whales in this region; however, to use passive acoustic data to monitor right whales most effectively, fine-scale temporal patterns in call production must be determined. To assess calling behavior and evaluate the relationship between right whale call production and environmental conditions, we deployed a 4 unit free-floating geo-referenced passive acoustic listening array and oceanographic sampling station in NPRW critical habitat from 1800 (local) August 6 – 1000 August 7, 2008 (~16 hours), and 1200 July 26 – 1500 July 28, 2009 (~51 hours). All calls were manually logged and classified into four categories (gunshot, moan, upcall, downsweep), and these call logs were used to assess call rates, bout lengths, temporal patterns in calling, and caller interactions (through localization of caller positions). Overall call rates varied over the course of each drifting station. Variability in call production in this study appears to be behaviorally driven, as no changes were observed in the environment. The three NPRW gunshot bouts with the most calls in 2009 illustrate two gunshot display contexts: 1) a long display by a single whale, and 2) concurrent displays by two separate whales separated by 1.5 km. The localized calls included in the single, long display fell within a distinct pattern of gunshots that was repeated throughout the duration of the bout. The pattern included a doublet of high amplitude gunshots, followed by a lower amplitude single gunshot; this combination was repeated 3 – 15 times. To our knowledge, this is the first description of patterned gunshot production by NPRWs. In the reproductive context, male gunshot displays are hypothesized to serve as an advertisement signal to females, an agonistic signal towards other males, or both. The extensive, patterned gunshot display by a lone whale in 2009 fits into the framework of advertisement. That the two whales producing concurrent gunshot bouts did not move towards each other may support the notion that these displays serve a male spacing, agonistic, or coordinated movement function. As concluded for other right whale species, it seems likely that this call type serves multiple purposes. Participants
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