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At the onset of the winter breeding season, male humpback whales begin a prominent breeding behaviour, singing. Early songs are produced on summer feeding grounds prior to migration, but little is ...

Blue whales Balaenoptera musculus in the Indian Ocean (IO) are currently thought to represent 2 or 3 subspecies (B. m. intermedia, B. m. brevicauda, B. m. indica), and believed to be structured into 4 populations, each with a diagnostic song-type. Here we describe a previously unreported song-type that implies the probable existence of a population that has been undetected or conflated with another population. The novel song-type was recorded off Oman in the northern IO/Arabian Sea, off the western Chagos Archipelago in the equatorial central IO, and off Madagascar in the southwestern IO. As this is the only blue whale song that has been identified in the western Arabian Sea, we label it the ‘Northwest Indian Ocean’ song-type to distinguish it from other regional song-types. Spatiotemporal variation suggested a distribution west of 70°E, with potential affinity for the northern IO/Arabian Sea, and only minor presence in the southwestern IO. Timing of presence off Oman suggested that intensive illegal Soviet whaling that took 1294 blue whales in the 1960s likely targeted this population, as opposed to the more widely distributed ‘Sri Lanka’ acoustic population as previously assumed. Based upon geographic distribution and potential aseasonal reproduction found in the Soviet catch data, we suggest that if there is a northern IO subspecies (B. m. indica), it is likely this population. Moreover, the potentially restricted range, intensive historic whaling, and the fact that the song-type has been previously undetected, suggests a small population that is in critical need of status assessment and conservation action.

The current known distribution of Omura’s whale includes the tropical and warm temperate waters of the western Pacific, Indian, and Atlantic Oceans. Evidence of their presence in the Atlantic Ocean is based on beach cast specimens found on the coasts of Mauritania (North Atlantic) and Northeastern Brazil (South Atlantic). The present study characterizes the occurrence of this species in the São Pedro and São Paulo Archipelago (SPSPA), on the mid-Atlantic ridge between South America and Africa, based on autonomous recording systems. Acoustic signals were similar, but not identical, to B. omurai vocalizations recorded off the coast of Madagascar. Although these signals were recorded for only 11 months, there are peaks in vocal activity between May and June in the vicinities of SPSPA, suggesting either a shift in distribution within the Atlantic equatorial waters or seasonality in the species’ vocal behavior in this region. The first acoustic records of Omura’s whales in the Equatorial Atlantic suggest that these animals may also use deep-water habitats, in addition to the shallow-water habitat use observed in other regions., A atual distribuição conhecida da baleia-de-Omura (Balaenoptera omurai) inclui as águas tropicais e temperadas quentes dos oceanos Pacífico ocidental, Índico e Atlântico. A evidência de sua presença no oceano Atlântico baseia-se em espécimes encalhados encontrados em praias da Mauritânia (Atlântico Norte) e do Nordeste do Brasil (Atlântico Sul). O presente estudo caracteriza a ocorrência dessa espécie no Arquipélago de São Pedro e São Paulo (ASPSP), localizado sobre a Dorsal Mesoatlântica entre a América do Sul e a África, com base em sistemas de monitoramento acústico passivo. Os sinais acústicos detectados foram similares, mas não idênticos, às vocalizações de B. omurai gravadas na costa de Madagascar. Embora esses sinais tenham sido registrados por apenas 11 meses, há picos na atividade vocal entre maio e junho nas proximidades do ASPSP, sugerindo uma mudança na distribuição da espécie nas águas equatoriais do Atlântico ou uma sazonalidade no comportamento vocal nessa região. Os primeiros registros acústicos das baleias-de-Omura no Atlântico Equatorial sugerem que esses animais também podem utilizar habitats de águas profundas, além de habitats de águas rasas como observado em outras regiões.

Humpback whale songs have been described worldwide and studies exploring non-song vocal behavior continue to expand; however, studies on the transition periods when whales shift to and from the seasonal behavioral state of singing are lacking and may be potentially informative regarding the proximal factors controlling the onset and offset of humpback whale male singing. Acoustic recorders collected data off eastern Canada continuously from the Bay of Fundy in the fall of 2015 and near-continuously off northeast Nova Scotia in the spring of 2016. Humpback whale acoustic occurrence and behavior were identified by systematically reviewing a subset of acoustic recordings for presence before analyzing the highest quality recordings for behavior. The onset of singing in the fall was gradual over a period of about three weeks with an intermediate form, termed "song fragment," occurring prior to full songs. In comparison, singing in the spring seemed to end abruptly with few song fragments. Song fragments could be produced by juveniles learning to sing for the first time or mature males preparing for breeding activities prior to migrating to southern breeding grounds. The authors propose an alternative hypothesis that the timing and manner of transitions could be driven by physiological processes similar to those documented in songbirds.

Photogrammetry is a powerful tool for taking indirect measurements of free-ranging marine mammals, and small unmanned aircraft systems (sUASs) are expanding the ways in which these images for morphometric analysis can be collected. A sUAS allows for photographs and videos to be captured from highly controllable positions and orientations, largely untethered from the physical location and constraints of the operator. This flexibility allows researchers to study and record agile cetaceans which can exhibit unpredictable swimming behaviors, such as Omura’s whales (Balaenoptera omurai). However, purpose built sUASs can be prohibitively expensive, require specialized expertise to operate, and require resources not available to many field biologists. Large multirotor aircrafts can require significant time and space for launch and recovery, and the vehicle can pose a hazard to those operating in its vicinity. By comparison, consumer grade unmanned aerial vehicles (UAVs), or drones, continue to become increasingly inexpensive, reliable, and compact. We tested seven commercially available UAV products from five leading consumer drone manufacturers and gauged their ability to be used at sea and for cetacean photogrammetry. These preliminary experiments informed our selection of equipment which we trialed during a targeted field expedition off the coast of Nosy Be, Madagascar. Over the course of a three week survey, we compared the efficacy of a consumer grade, off-the-shelf UAV with a custom solution of comparable size and price. Both sUASs were successfully able to collect data which translated to animal size measurements. We provide both specific guidelines for selecting, testing, and calibrating consumer grade UAVs to be used on ocean-based expeditions, as well as procedures for conducting morphometric analyses with the resulting data. Our data analysis procedures are based on established methods of morphemic analysis of cetaceans photographed in single still images. Our software is freely available for other to use and modify.

Elucidating patterns of population structure for species with complex life histories, and disentangling the processes driving such patterns, remains a significant analytical challenge. Humpback whale (Megaptera novaeangliae) populations display complex genetic structures that have not been fully resolved at all spatial scales. We generated a data set of nuclear markers for 3575 samples spanning the seven breeding stocks and substocks found in the South Atlantic and western and northern Indian Oceans. For the total sample, and males and females separately, we assessed genetic diversity, tested for genetic differentiation between putative populations and isolation by distance, estimated the number of genetic clusters without a priori population information and estimated rates of gene flow using maximum-likelihood and Bayesian approaches. At the ocean basin scale, structure is governed by geographical distance (IBD P

Funding:Commander, U.S. Pacific Fleet Environmental Readiness Division and NMFS Pacific Islands Fisheries Science Center; NMFS West Coast Region; Scripps Institution of Oceanography Edna Bailey Sussman Research Fellowship; and Woods Hole Oceanographic Institution. Genomic phylogeography plays an important role in describing evolutionary processes and their geographic, ecological, or cultural drivers. These drivers are often poorly understood in marine environments, which have fewer obvious barriers to mixing than terrestrial environments. Taxonomic uncertainty of some taxa (e.g., cetaceans), due to the difficulty in obtaining morphological data, can hamper our understanding of these processes. One such taxon, the short‐finned pilot whale, is recognized as a single global species but includes at least two distinct morphological forms described from stranding and drive hunting in Japan, the “Naisa” and “Shiho” forms. Using samples (n = 735) collected throughout their global range, we examine phylogeographic patterns of divergence by comparing mitogenomes and nuclear SNP loci. Our results suggest three types within the species: an Atlantic Ocean type, a western/central Pacific and Indian Ocean (Naisa) type, and an eastern Pacific Ocean and northern Japan (Shiho) type. mtDNA control region differentiation indicates these three types form two subspecies, separated by the East Pacific Barrier: Shiho short‐finned pilot whale, in the eastern Pacific Ocean and northern Japan, and Naisa short‐finned pilot whale, throughout the remainder of the species' distribution. Our data further indicate two diverging populations within the Naisa subspecies, in the Atlantic Ocean and western/central Pacific and Indian Oceans, separated by the Benguela Barrier off South Africa. This study reveals a process of divergence and speciation within a globally‐distributed, mobile marine predator, and indicates the importance of the East Pacific Barrier to this evolutionary process. Postprint

Acoustic recordings of two closely related species, spinner dolphin (Stenella longirostris) and pantropical spotted dolphin (Stenella attenuata), were investigated from four different geographic locations: two in the Central Tropical Pacific, one in the Eastern Tropical Pacific and one in the Indian Ocean. The two delphinid species occur in tropical and warm temperate waters, with overlapping ranges. They produce very similar vocalizations, but at the same time their calls exhibit a certain degree of intraspecific variation among different geographic locations as has been observed in other delphinid species. Oscillatory whistles (whistles with at least two oscillations in their frequency contours) were identified and manually extracted from the recordings. Whistles with four or more maxima (oscillations) occurred only in spinner dolphins and they were present in all geographic regions investigated. In addition, the oscillatory whistles with two and three maxima were significantly more frequent in spinner than in spotted dolphins. The differences in oscillatory whistles for these two species seem to be consistent across study areas and therefore, could be used in addition to other whistle features to help distinguish between them

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Assessing the movement patterns and key habitat features of breeding humpback whales is a prerequisite for the conservation management of this philopatric species. To investigate the interactions between humpback whale movements and environmental conditions off Madagascar, we deployed 25 satellite tags in the northeast and southwest coast of Madagascar. For each recorded position, we collated estimates of environmental variables and computed two behavioural metrics: behavioural state of ‘transiting’ (consistent/directional) versus ‘localized’ (variable/non-directional), and active swimming speed (i.e. speed relative to the current). On coastal habitats (i.e. bathymetry aconcentrations. Active swimming speed accounts for a large proportion of observed movement speed; however, breeding humpback whales probably exploit prevailing ocean currents to maximize displacement. This study provides evidence that coastal areas, generally subject to strong human pressure, remain the core habitat of humpback whales off Madagascar. Our results expand the knowledge of humpback whale habitat use in oceanic habitat and response to variability of environmental factors such as oceanic current and chlorophyll level.

Consistent and well-defined criteria for the classification and measurement of humpback whale song features are essential for robust comparisons between investigators. Song structure terminology has been well-established and used by many authors, though at times inconsistently. This review discusses the development of the nomenclature describing humpback song and explores the potential significance of the often-overlooked variation in song patterns. Within the hierarchical definition of humpback song, the most problematic issues arise from the inconsistent delineation of phrase types, and the use of the metric of song duration without regards to variability in thematic sequence. With regards to the former, a set of guidelines is suggested to facilitate consistent delineation of phrases. With regards to the latter, current research demonstrates that the “song duration” metric has resulted in the disregard of variability at this level, which is more widespread than traditionally reported. An exemplar case is used to highlight the problem inherent in defining and measuring song duration. Humpback song is evaluated within the framework of avian songbird research, and a shift in analysis paradigm is recommended, towards phrase-based analyses in which sequences of phrases are treated as a salient feature of song pattern.

Movements of humpback whales Megaptera novaeangliae among breeding regions within the southwestern Indian Ocean are poorly understood. Understanding the relationships among breeding regions is critical for effective conservation and management strategies. Through systematic comparisons of molecular genotypes and both systematic and non-systematic comparisons of individual identification photographs collected between 1996 and 2006, we have thus far identified nine whales (six males and three females) utilising two breeding areas within this region: the northern Mozambique Channel and eastern Madagascar. Four of the nine whales were recaptured using only photographic data, two whales were independently recaptured using both photographic and genetic data, and three whales were recaptured exclusively using molecular methods. The discovery of these nine individuals provides much-needed data to guide the formulation and future revision of stock boundaries.

Comparing humpback whale song from different breeding assemblages can reveal similarities in song due to acoustically interacting males, and therefore indirectly test whether males from different breeding sites are mixing. Northern Hemisphere song comparisons illustrated that whales within ocean basins share similar songs and are subpopulations within a larger population, whereas whales in different ocean basins are isolated populations and therefore do not share songs. During the 2006 breeding season, recordings were collected in Madagascar and Western Australia, and were compared visually plus aurally. Both regions shared one theme, whereas each region had four and six private themes, respectively. This study had a substantially low number of shared themes. The co-occurrence of one theme was interpreted as an indication of limited exchange between these breeding assemblages, and we speculate that limited song similarity is due to inter-oceanic interactions. Male(s) from an Indian Ocean breeding group could be exposed to novel song when they geographically overlap, and acoustically interact, with males from a different ocean basin. Novel song could induce rapid temporal changes as new song content is incorporated, thereby minimizing song similarities between that breeding group and other Indian Ocean breeding groups that were not exposed to the novel song.

We examined the incidence of rake mark scars from killer whales Orcinus orca on the flukes of humpback whales Megaptera novaeangliae throughout the North Pacific to assess geo- graphic variation in predation pressure. We used 3650 identification photographs from 16 wintering or feeding areas collected during 1990 to 1993 to determine conservative estimates in the percentage of whales with rake mark scarring. Dramatic differences were seen in the incidence of rake marks among regions, with highest rates on wintering grounds off Mexico (26 vs. 14% at others) and feed- ing areas off California (20 vs. 6% at others), 2 areas between which humpback whales migrate. Although attacks are rarely witnessed, the prevalence of scars demonstrates that a substantial por- tion of animals are attacked, particularly those that migrate between California and Mexico. Our data also suggest that most attacks occur at or near the wintering grounds in the eastern North Pacific. The prevalence of attacks indicates that killer whale predation has the potential to be a major cause of mortality and a driving force in migratory behavior; however, the location of the attacks is inconsis- tent with the hypothesis that animals migrate to tropical waters to avoid predation. Our conclusion is that, at least in recent decades, attacks are made primarily on calves at the wintering grounds; this contradicts the hypothesis that killer whales historically preyed heavily on large whales in high- latitude feeding areas in the North Pacific.

The Indian Ocean humpback dolphin (Sousa plumbea) has been studied in several range states in the Southwest Indian Ocean, however little information exists on populations in Madagascar. Here, we review available literature and describe a study on S. plumbea conducted between 2004 and 2013 on the west coast of Madagascar, involving boat-based field surveys in the southwest and northwest regions, and interview surveys with local fishers from villages along most of the west coast. Field surveys in the southwest region of Anakao/St. Augustine Bay revealed low encounter rates and mean group size, and markedly declining trends in both from 1999 to 2013. Conversely, in the northwest region around Nosy Be and Nosy Iranja, encounter rates were higher, as were mean group sizes, suggesting an apparently more abundant and less impacted population. Interview surveys revealed by-catch of coastal dolphins along the entire west coast, including S. plumbea, as well as other species. Directed hunting, including drive hunts of groups of dolphins, was reported primarily in the southern regions, in the range of the Vezo Malagasy ethnicity; however, there was evidence of hunting starting in one area in the northwest, where hunting dolphins is normally considered taboo for the predominant Sakalava ethnicity. Thus, the conservation status of S. plumbea in Madagascar appears to be spatially heterogeneous, with some areas where the local population is apparently more impacted than others. Conservation measures are recommended to mitigate further decline in the southwest of Madagascar, while protecting habitat and ensuring resilience in the northwest.

Indian Ocean humpback dolphins (Sousa plumbea) are obligate shallow-water dolphins that occur exclusively in the near-shore waters of the Indian Ocean, from South Africa to the Bay of Bengal. They have a narrow habitat preference, restricted distribution and do not appear very abundant across any part of their range. There is no estimate of total species abundance; all populations that have been quantitatively evaluated have been small in size, usually fewer than 200 individuals. Fishing, dredging, land reclamation, construction blasting, port and harbour construction, pollution, boat traffic and other coastal development activities all occur, or are concentrated within, humpback dolphin habitat and threaten their survival. Although data are far from sufficient to make a rigorous quantitative assessment of population trends for this species, the scale of threats is large enough over a significant enough portion of the range to suspect or infer a decline of at least 50% over three generations, which qualifies it for listing on the IUCN Red List as Endangered. The issue primarily responsible is incidental mortality in fisheries, but the loss and degradation of habitat is likely a contributing factor. None of the threats have been adequately addressed in any part of the species' range, even though threat levels are increasing virtually everywhere.

Based on whole mtDNA sequencing of 14 samples from Northern Island Melanesia, we characterize three formerly unresolved branches of macrohaplogroup M that we call haplogroups M27, M28, and M29. Our 1,399 mtDNA control region sequences and a literature search indicate these haplogroups have extremely limited geographical distributions. Their coding region variation suggests diversification times older than the estimated date for the initial settlement of Northern Island Melanesia. This finding indicates that they were among the earliest mtDNA variants to appear in these islands or in the ancient continent of Sahul. These haplogroups from Northern Island Melanesia extend the existing schema for macrohaplogroup M, with many independent branches distributed across Asia, East Africa, Australia, and Near Oceania.

Mating system theory predicts that differences between the sexes in potential reproductive rate and an operational sex ratio skewed strongly towards males should result in intense male competition, polygynous mating and high variance in male reproductive success. Accordingly, humpback whales are thought to be polygynous with differences in reproduction among males related to alternative mating tactics. However, there is currently a lack of data on male reproductive success. We tested predictions regarding male reproductive success in humpback whales using molecular assessment of paternity in a population in the Mexican Pacific. Parentage analysis was conducted for 125 mother–calf pairs and a sample of 297 males using 13 microsatellite loci. Two separate analyses were conducted, based upon conservative and relaxed criteria for the assignment of paternity. In the conservative analysis, 40 paternities (32.5% of tested calves) were assigned among 33 males, whereas in the relaxed analysis, 62 paternities (49.6% of calves) were assigned among 51 males. Regardless of analysis, the distribution of male reproductive success deviated from a random mating model, with significantly larger than expected variance (conservative, P = 0.011; relaxed, P = 0.022), and significantly more than expected males siring three calves (conservative, P = 0.021; relaxed, P = 0.011). However, most successful males sired only one calf and no male was assigned more than three calves, so reproductive skew was not severe. Therefore we conclude that this population has a polygynous mating system, but without the large variation in male reproductive success expected by apparent skew in the operational sex ratio and degree of male competition for mates.

We used photo-identification records to estimate annual survival of adult humpback whales (Megaptera novaeangliae) for the central North Pacific stock using models within the software application Program MARK. The analysis is based on 10,567 photographs of 2,400 individual whales taken from 1979 to 1996. The central North Pacific stock winters in Hawai'i and migrates to discrete feeding areas in Alaska for the summer and autumn. The Cormack-Jolly-Seber (CJS) estimate of annual survival based on annual sightings in Hawai'i was 0.963 (95% confidence interval [CI]: 0.944-0.978) and the Pradel estimate was 0.963 (95% CI: 0.944-0.976), with a population rate of increase of 1.10 (95% CI: 1.03-1.16). The best survival estimate for southeastern Alaska whales, based on Barker's model, was 0.957 (95% CI: 0.943-0.967). The best survival estimate for Prince William Sound whales, also based on Barker's model, was 0.984 (95% CI: 0.954-0.995). Whales from the central North Pacific stock mix in Hawai'i; therefore, the best apparent survival estimate for the entire stock is from the pooled Hawai'i data. However, this analysis also demonstrated that we could reduce heterogeneity with Barker's model and obtain more plausible estimates of survival for the whales in discrete feeding areas using semiannual sightings in Hawai'i as opportunistic resightings.

The Indian Ocean humpback dolphin (Sousa plumbea) has been studied in several range states in the Southwest Indian Ocean, however little information exists on populations in Madagascar. Here, we review available literature and describe a study on S. plumbea conducted between 2004 and 2013 on the west coast of Madagascar, involving boat-based field surveys in the southwest and northwest regions, and interview surveys with local fishers from villages along most of the west coast. Field surveys in the southwest region of Anakao/St. Augustine Bay revealed low encounter rates and mean group size, and markedly declining trends in both from 1999 to 2013. Conversely, in the northwest region around Nosy Be and Nosy Iranja, encounter rates were higher, as were mean group sizes, suggesting an apparently more abundant and less impacted population. Interview surveys revealed by-catch of coastal dolphins along the entire west coast, including S. plumbea, as well as other species. Directed hunting, including drive hunts of groups of dolphins, was reported primarily in the southern regions, in the range of the Vezo Malagasy ethnicity; however, there was evidence of hunting starting in one area in the northwest, where hunting dolphins is normally considered taboo for the predominant Sakalava ethnicity. Thus, the conservation status of S. plumbea in Madagascar appears to be spatially heterogeneous, with some areas where the local population is apparently more impacted than others. Conservation measures are recommended to mitigate further decline in the southwest of Madagascar, while protecting habitat and ensuring resilience in the northwest.

Omura’s whale is a recently described tropical Balaenopterid whale with virtually nothing known about their acoustic behavior. Recordings have revealed a stereotyped 15-50 Hz amplitude-modulated vocalization, rhythmically repeated in a typical Balaenoptera song manner. In order to describe the characteristics of the song, continuous recordings were made using archival recorders during 21 days at 4 sites off the northwest coast of Madagascar in documented Omura’s whale habitat. A total of 926 hours of recordings were manually browsed to identify all occurrences of the song vocalizations, logging 9117 individual song units. Occurrence varied among sites spread across 40 km of shelf habitat, indicating heterogeneous distribution of whales and use of habitat over space and days. Diel variation indicated higher incidence of song during daylight hours, counter to trends found in other Balaenopterid whales. A total of 215 different individual series were identified ranging from 3 to 252 consecutive song units. F...

Passive acoustic monitoring was used to document the presence of singing humpback whales off the coast of Northern Angola, and opportunistically test for the effect of seismic survey activity in the vicinity on the number of singing whales. Two Marine Autonomous Recording Units (MARUs) were deployed between March and December 2008 in the offshore environment. Song was first heard in mid June and continued through the remaining duration of the study. Seismic survey activity was heard regularly during two separate periods, consistently throughout July and intermittently in mid-October/November. Numbers of singers were counted during the first ten minutes of every hour for the period from 24 May to 1 December, and Generalized Additive Mixed Models (GAMMs) were used to assess the effect of survey day (seasonality), hour (diel variation), moon phase and received levels of seismic survey pulses (measured from a single pulse during each ten-minute sampled period) on singer number. Application of GAMMs indicated significant seasonal variation, which was the most pronounced effect when assessing the full dataset across the entire season (p

Humpback whale song, a male breeding display, shows a remarkable degree of similarity among distant breeding assemblages, despite constant progressive change. It has been hypothesized that whales maintain continuity through cultural transmission via migratory movements of males. We examined songs of whales breeding off Hawaii and Mexico to determine whether they changed similarly in both areas during the course of a breeding season. Songs recorded off Kauai, Hawaii (11 individuals) and Isla Socorro, Mexico (13 individuals) during winter and spring of 1991, were compared qualitatively and quantitatively. We measured 44 acoustic variables describing all known levels of song structure for each singer and we grouped these variables into six categories. We used two-factor analyses of variance to assess change across the season in each area, comparing the two regions and two 3-week periods (January/February and April). Twenty-seven variables changed significantly during the 12-week study in at least one area. Variables within categories displayed similar trends of change. Time and frequency characteristics describing the structure of song elements (units and phrases) changed synchronously in each area, with 21 of 25 variables displaying significant differences between periods and no interaction with region. Structures of song patterns, as defined by frequency of occurrence and number of unit and phrase types, changed differently in each area, with five of 12 variables indicating a significant interaction between region and period. Our results may suggest cultural transmission during the season, since many variables changed in similar manners. We propose an alternative hypothesis, that whales may be predisposed to gradually change certain features of song independently of cultural influences; change of structural elements may be governed by a discrete set of rules, or according to an innate template. Therefore, continuity of song patterns across the ocean basin may be due to a combination of mechanisms, only partially involving cultural transmission. We assess these hypotheses in relation to humpback whale behaviour and population structure, and cultural transmission and evolution of avian song.

Sighting histories of individually identified female humpback whales (Megaptera novaeangliae) in their win- ter and summer ranges were used to investigate mortality of North Pacific humpback whale calves. We compiled re- cords collected between 1979 and 1995 by eight independent research groups, which yielded 29 cases where 25 different mothers sighted in Hawaii were identified later the same year in Alaska. In 7 of 29 cases, a calf sighted with its mother in Hawaii was missing from its mother's Alaska sighting(s). After investigating many factors, we deter - mined that the largest potential bias would occur in late-autumn observations, when calf absences might indicate wean- ing or temporary mother-calf separation rather than calf mortality. Our minimal and most robust estimate excluded all mortalities and survivals based on sightings of the mother after October 31; 3 of 20 cases or 0.150 (95% confidence intervals (CI) = 0.032, 0.378). The maximal calf mortality rate, derived from all the available data, was 7 of 29 cases or 0.241 (95% CI = 0.103, 0.434). An intermediate estimate that excluded all cases based on single Alaska sightings and omitted late-season sightings (2 of 11 cases or 0.182; 95% CI = 0.023, 0.518) is perhaps closest to the actual first- year mortality rate for humpback whale calves, although it is compromised by its small sample size. Our results dem- onstrate both the value and the limitations of using longitudinal data to determine the life-history parameters that are essential for documenting the recovery of endangered populations. 600 Resume : L'observation suivie de Baleines a bosse (Megaptera novaeangliae) femelles identifiees individuellement dans leurs aires d'hiver et d'ete a permis d'etudier la mortalite des petits dans la population du Pacifique Nord. Nous avons compile des donnees obtenues de 1979 a 1995 par huit groupes independants de chercheurs et l'operation a revele 29 cas ou 25 meres differentes apercues dans les eaux hawaiennes ont ete observees de nouveau en Alaska plus tard la meme annee. Dans 7 des 29 cas, une mere apercue a Hawaii avec son petit a ete revue en Alaska sans son petit. Apres avoir examine plusieurs facteurs, nous avons determine que la cause la plus probable d'erreur potentielle etait reliee aux observations de fin d'automne, alors que l'absence du petit pourrait s'expliquer par le sevrage ou par la separation temporaire du petit d'avec sa mere, plutot que par la mortalite. Notre estimation minimale la plus robuste ne tient pas compte des taux de mortalite et de survie bases sur les observations des meres apres le 31 octobre; 3 cas sur 20 ou 0,150 (95 % IC = 0,032, 0,378). Le taux maximal de mortalite des petits, base sur toutes les donnees, etait de 7 cas sur 29 ou 0,241 (95 % IC = 0,103, 0,434). Une estimation moyenne excluant tous les cas d'observations uniques en Alaska et les observations de fin de saison (2 cas sur 11 ou 0,182; 95 % IC = 0,023, 0,518) est peut etre plus pres de la mortalite reelle des petits au cours de la premiere annee, bien que les resultats soient compromis par la taille

Vocalizations of feeding humpback whales from southeast Alaska were analyzed to characterize quantitatively the predominant vocalization associated with feeding and assess variation among vocalizations. Whales uttered series of cries similar in acoustic structure to those described previously as stereotyped, rhythmic ‘feeding calls’. Individual cries ranged in duration from 0.4 to 8.2 sec. (median = 2.6 sec). Cries typically had a short, strongly frequency modulated (FM) introductory and ending component (labeled Section A and C, respectively). Cries had relatively little FM over the main body of the call (labeled Section B) which ranged in fundamental frequency from 360 to 988 Hz (median = 553 Hz) and sometimes exhibited a frequency oscillation over a bandwidth of approximately 16 to 65 Hz. Principle components analysis indicated that most variation in the data-set (over 35%) could be attributed to measures of absolute frequency, however a substantial amount of variation was also due to other ac...

The migratory destinations of humpback whales that feed off California. Oregon and Washington were determined using photo-identification. Fluke photographs of 594 individuals were taken between 1981 and 1992 and compared to collections from 9 wintering regions in the North Pacific: Ogasawara (162) and Okinawa (17) islands of Japan; the Big Island and Maui (634 for both) and Kauai (384) of Hawaii; the Revillagigedo Archipelago (450), the mainland coast (383) and Baja Peninsula (471) of Mexico; and Central America (31). A total of 160 matches were found to 6 central and eastern North Paclfic wintering regions, with most from Central America, Baja, and mainland Mexico. Of whales identified off Central America, 84 % were resighted off California-Washington, this high rate of interchange suggests that whales in these tropical waters appear to be comprised entirely of animals from the California-Washington feeding aggregation. Humpback whales seen off Central America were reslghted disproportionately off southern California while those from mainland ~Vexico tended to be seen off northern California-Washington. From 157 same-season migratory transits documented, the shortest were 29 d to Baja and 56 d to Costa Rica and the longest distance was 5322 km. Of the California-Washington whales with known sex, the proportion of males identified at a wintering region was significantly higher than females (2.2:1, p < 0.05).

Cetacea has traditionally been divided into Odontoceti, the toothed whales, and Mysticeti, the baleen whales. These groups have been considered monophy? letic, although their origins and age have been historically debated. Recently, Mil? inkovitch et al. (1993, 1994) reported a revised phylogeny for Cetacea, based upon phylogenetic analysis of mitochon? drial DNA (mtDNA), that challenges the classical assumption of odontocete mono? phyly. Their phylogenetic hypotheses were based initially on two mitochondrial ribosomal gene segments (930 base pairs [bp] from the 12S and 16S genes) from 16 species of cetaceans, an artiodactyl, and 2 more distantly related outgroup taxa (Milinkovitch et al., 1993), and then from an expanded data set of the ribosomal sequences plus a segment of cytochrome b (for a total of 1,352 bp) from 21 ceta? ceans and 3 artiodactyls (Milinkovitch et al., 1994). In these revised phylogenies, Physeteroidea (the sperm whales) were placed as a sister group to Mysticeti, indi? cating that Physeteroidea are more closely related to Mysticeti than to the other Odontoceti, and inferring paraphyly of the odontocetes. The authors have strongly promoted this hypothesis (Milinkovitch et al., 1993,1994,1995,1996) to the extent of suggesting a complete reinterpretation of cetacean morphologi? cal evolution (Milinkovitch, 1995). The conclusions of Milinkovitch et al.

Identification photographs of individual humpback whales Megaptera novaeangliae were used to investigate movements of whales between Kauai and Hawaii (approximately 500 km apart; the Hawaiian Islands, USA) durlng the winter and spring months of 1989, 1990 and 1991. A total of 1072 individuals were identified, with 40 individuals being sighted off both islands. There were 15 documented transits between islands within seasons; 9 whales traveled northwest (from Hawaii to Kauai), whereas 6 whales traveled southeast (Kauai to Hawaii). S~mulation data indicated that these transitdirection proportions did not deviate from random expectations (p = 0.76); therefore, there was no directional trend to movement between the islands. The shortest observed transit was 8 d, indicating that whales can move throughout the island chain in short periods. Males were significantly overrepresented in inter-island recaptures (p < 0.001), and we suggest that males actively engaged in courtship behaviors are more wide-ranging. Whales did not show a significant trend to be captured off the same island in different years (p = 0.08 for Kauai, p = 0.12 for Hawaii); however, recaptures were few, power was relatively low, and 1 test approached significance. The observed number of within-season, between-island recaptures was significantly less than expected as determined by random sirnulations (p = 0.013 for Kauai, p = 0.008 for Hawaii), indicating that, during a season, whales are more likely to be recaptured off the isldnd of ~nitial capture. There was also evidence suggesting that sub-groups of whales moved among tht. lslands in loose aggregations within seasons, the number of pairs of individuals captured off both islands within 7 d of each other was significantly greater than expected in random simulations ( p = 0.038). We conclude that complete random mixing of whales among the islands is unlikely, and should not be assumed in the context of mark-recapture abundance estimation. Larger samples with greater coverage of the Hawaiian lslands and higher recapture probability will be needed to elucidate movement patterns of the population.

Songs of humpback whales off Hawaii and Mexico were examined to determine whether they changed similarly in both areas during a breeding season. Songs of 24 individuals were recorded off Kauai, Hawaii and Isla Socorro, Mexico during winter and spring of 1991. Forty‐seven acoustic variables describing all levels of song structure were measured for each singer. Similar variables were grouped together into six categories. Mean values for each singer were compared among regions and time periods using two‐factor ANOVAs. All but three variables changed between winter and spring in at least one area. Groups of similar variables displayed similar trends. Quantitative characteristics of song elements often changed during the breeding season by the same amount in each area, with little variation within and among individuals. Structures of song patterns often changed differently in each area. Results indicated cultural transmission may have occurred during the season. Alternatively, whales may be predisposed to gradually change features of song independent of cultural influences. Given the low level of variability exhibited by many variables, the latter seems more likely; therefore, temporal change, like song structure, may be governed by a discrete set of rules. Further research on a longer time scale is needed.

Marine mammals, including coastal dolphins, West African manatees, offshore cetaceans (baleen whales and larger odontocetes), and marine turtles are increasingly under threat; many are rare, although some cetaceans are showing recovery from commercial exploitation. When Angola Liquefied Natural Gas (LNG) began using Chevron's Operational Excellence Process for Environmental, Social and Health Impact Assessment (ESHIA) to manage the potential environmental impacts of a proposed LNG facility in the Congo River Basin, they collaborated with the Wildlife Conservation Society (WCS) to address issues identified in the Angola LNG ESHIA Process and to develop programs to protect the marine turtles and marine mammals through cooperative science and management, training, and education. The Marine Mammal Program fieldwork, conducted by WCS and Angola LNG in the Congo River Basin area and South Atlantic coastline near Soyo, Angola, was completed between 2008 and 2009. Activities included the assessment of inshore and Congo River environments and marine mammals, and the use and deployment of Marine Autonomous Recording Units (MARUs; shown in Figure 1) as a cost-effective means of surveying whales in the South Atlantic Ocean. This was the first time MARUs were used off the coast of West Africa. The MARUs allowed for long periods of continuous monitoring for vocalizing cetaceans, cetacean behavior and anthropogenic contributions to ocean ambient noise with relatively minor field effort. The technique also allowed for uninterrupted acoustic monitoring investigations, otherwise impossible with boat-based visual methods during night hours and inclement weather. However, there were certain challenges in using the MARUs, such as the analysis and management of large datasets, as well as the identification of signals in the recordings when there is little to no possibility of verifying all possible signals through simultaneous visual surveys and sightings. Due to logistical and safety limitations for conducting numerous offshore surveys for identification, existing data from other parts of the world were used for comparisons to confirm species of vocalizing whales. In many cases, some of the signals will remain unknown.

Cetacean by-catch in artisanal fisheries in the southwestern region of Madagascar was previously documented through surveys conducted in this region. To build on initial findings, a research project was conducted to further evaluate by-catch in this region. Interview surveys were conducted between October 2005 and January 2006 in four seaside villages to gather information on cetacean by-catch in artisanal fisheries. A total of 111 interviews were analyzed, resulting in an estimate in 56 by-catch events in the four villages between 2000 and 2005. These events involved in an estimate of 79 animals entangled in fishing gear, which we believe is an underestimate. Three dolphin species and humpback whales were reported accidentally caught in fishing gear meant to catch sharks. Dolphins were mostly reported as to be entangled in gillnets; conversely longlines were only described to incidentally catch humpback whales. Bottlenose and spinner dolphins were respectively 48.10% and 31.64% of total cetacean by-catch between 2000 and 2005. Improved fisheries management and effective cetacean population management are needed to mitigate threats to cetaceans from artisanal fisheries in the southwestern region.

Knowledge of cetacean presence in west African waters is sparse due to the remote and logistically challenging nature of working in these waters. Exploration and Production (EP therefore, collecting baseline information on species distribution is important. Previous research is limited although a number of species listed as vulnerable or data deficient by the IUCN red list have been documented. In 2012/2013, we deployed an array of eight Marine Autonomous Recording Units (MARUs) in a series of three deployments, off Northern Angola, targeting Mysticetes (2 kHz SR, continuous) during winter/spring and Odontocetes (32 kHz SR, 20% duty cycled) during summer/autumn. Preliminary results are presented on the temporal and spatial distribution of species identified from automated and manual detection methods. Humpback whales were frequently detected from August through December, with peaks during September/October. During the deployment period, sperm whales and Balaenopterid and Odontocete calls were also detected and possible species will be discussed. Species detections will be used to identify temporal hotspots for cetacean presence and any potential overlap with E&P activities. We recommend that future research efforts include visual and acoustic vessel surveys to increase the utility of passive acoustics for monitoring these populations.