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The gig economy and gig work have grown quickly in recent years and have drawn much attention from researchers in different fields. Because the platform mediated gig economy is a relatively new phenomenon, studies have produced a range of interesting findings; of interest here are the socio‐technical issues that this work has surfaced. This systematic literature review (SLR) provides a snapshot of a range of socio‐technical issues raised in the last 12 years of literature focused on the platform mediated gig economy. Based on a sample of 515 papers gathered from nine databases in multiple disciplines, 132 were coded that specifically studied the gig economy, gig work, and gig workers. Three main socio‐technical themes were identified: (1) the digital workplace, which includes information infrastructure and digital labor that are related to the nature of gig work and the user agency; (2) algorithmic management, which includes platform governance, performance management, information asymmetry, power asymmetry, and system manipulation, relying on a diverse set of technological tools including algorithms and big data analytics; (3) ethical design, as a relevant value set that gig workers expect from the platform, which includes trust, fairness, equality, privacy, and transparency. A social informatics perspective is used to rethink the relationship between gig workers and platforms, extract the socio‐technical issues noted in prior research, and discuss the underexplored aspects of the platform mediated gig economy. The results draw attention to understudied yet critically important socio‐technical issues in the gig economy that suggest short‐ and long‐term opportunities for future research directions. [ABSTRACT FROM AUTHOR]

The 20th century commercial whaling industry severely reduced populations of great whales throughout the Southern Hemisphere. The effect of this exploitation on genetic diversity and population structure remains largely undescribed. Here, we compare pre- and post-whaling diversity of mitochondrial DNA (mtDNA) control region sequences for 3 great whales in the South Atlantic, such as the blue, humpback, and fin whale. Pre-whaling diversity is described from mtDNA extracted from bones collected near abandoned whaling stations, primarily from the South Atlantic island of South Georgia. These bones are known to represent the first stage of 20th century whaling and thus pre-whaling diversity of these populations. Post-whaling diversity is described from previously published studies reporting large-scale sampling of living whales in the Southern Hemisphere. Despite relatively high levels of surviving genetic diversity in the post-whaling populations, we found evidence of a probable loss of mtDNA lineages in all 3 species. This is evidenced by the detection of a large number of haplotypes found in the pre-whaling samples that are not present in the post-whaling samples. A rarefaction analysis further supports a loss of haplotypes in the South Atlantic humpback and Antarctic blue whale populations. The bones from former whaling stations in the South Atlantic represent a remarkable molecular archive for further investigation of the decline and ongoing recovery in the great whales of the Southern Hemisphere. [ABSTRACT FROM AUTHOR]

Forage fishes are a critical food web link in marine ecosystems, aggregating in a hierarchical patch structure over multiple spatial and temporal scales. Surface‐level forage fish aggregations (FFAs) represent a concentrated source of prey available to surface‐ and shallow‐foraging marine predators. Existing survey and analysis methods are often imperfect for studying forage fishes at scales appropriate to foraging predators, making it difficult to quantify predator–prey interactions. In many cases, general distributions of forage fish species are known; however, these may not represent surface‐level prey availability to predators. Likewise, we lack an understanding of the oceanographic drivers of spatial patterns of prey aggregation and availability or forage fish community patterns. Specifically, we applied Bayesian joint species distribution models to bottom trawl survey data to assess species‐ and community‐level forage fish distribution patterns across the US Northeast Continental Shelf (NES) ecosystem. Aerial digital surveys gathered data on surface FFAs at two project sites within the NES, which we used in a spatially explicit hierarchical Bayesian model to estimate the abundance and size of surface FFAs. We used these models to examine the oceanographic drivers of forage fish distributions and aggregations. Our results suggest that, in the NES, regions of high community species richness are spatially consistent with regions of high surface FFA abundance. Bathymetric depth drove both patterns, while subsurface features, such as mixed layer depth, primarily influenced aggregation behavior and surface features, such as sea surface temperature, sub‐mesoscale eddies, and fronts influenced forage fish diversity. In combination, these models help quantify the availability of forage fishes to marine predators and represent a novel application of spatial models to aerial digital survey data. [ABSTRACT FROM AUTHOR]

Investigates problems of using commercial search engines for Web-based research. Findings indicate that search engines are highly variable in their results, are limited in the search functions they offer, have poorly and/or incorrectly documented functions, use search logics that are opaque, and change search functions they offer over time. (Author/LRW)

Humpback whales (Megaptera novaeangliae) in the Southeastern Atlantic Ocean (International Whaling Commission 'Breeding Stock B'--BSB) are distributed from the Gulf of Guinea to Western South Africa. Genetic data suggest that this stock may be sub-structured, but it remains unknown if this is due to reproductive segregation. This paper evaluates the spatial and temporal population structure of BSB humpback whales using a combination of maternally and bi-parentally inherited markers. The genetic differentiation that we identify in this study could be due to a combination of (1) spatial and/or temporal segregation on breeding grounds in the greater Gulf of Guinea, (2) the possibility of maternally inherited site fidelity to specific feeding grounds and (3) the use of two generalized but exclusive migratory routes (coastal and offshore) between feeding and breeding areas. Further, photo-identification and genetic sampling efforts in other areas of the Sub-Saharan Western Africa winter range and targeted deployment of satellite tags would help to clarify some of the apparent complexity in the population structure of animals biopsied in this region., Introduction Understanding the processes by which marine populations diverge or remain homogeneous remains a major challenge in evolutionary biology. The accurate description of population genetic structure over a species geographic [...]

North Atlantic right whale (NARW) distribution shifts have led to increased presence in the US mid‐Atlantic, which includes the New York Bight (NYB), an area with substantial vessel traffic. NARW vessel strikes are mitigated by a seasonal management area (SMA) that is active November–April. Within the SMA, vessels ≥ 19.8 m must travel at ≤10 knots. However, until recently, surveys of the NYB were not conducted after the NARW distribution shifted. Thus, it was unclear whether the SMA captured NARW presence in the NYB. Outside the SMA, voluntary speed restrictions are implemented over a limited area when NARW calls are acoustically detected; therefore, it was important to quantify NARW vocal activity. Acoustic recordings (2016–2020) were analyzed to determine NARW presence, vocal states, and diel pattern of vocal activity. NARWs were detected outside SMA boundaries, and medium/high vocal states (21–69 calls over 3–6 h) occurred while the SMA was inactive. Therefore, the SMA spatiotemporal boundaries should be revised. Vocal activity was highest at night (22:00–1:00), and NARWs were acoustically detected when they were not detected by aerial surveys, illustrating acoustic detections are a viable method for triggering mitigation measures when NARWs are vocalizing but are not visually observed. [ABSTRACT FROM AUTHOR]

The New York Bight is undergoing rapid anthropogenic change amidst an apparent increase in baleen whale sightings. Though survey efforts have increased in recent years, the lack of published knowledge on baleen whale occurrence prior to these efforts impedes effective assessments of distributional or behavioural shifts due to increasing human activities. Here we synthesize opportunistic sightings of baleen whales from 1998–2017, which represent the majority of sightings data prior to recent survey efforts, and which are largely unpublished. Humpback and fin whales were the most commonly sighted species, followed by North Atlantic right whales and North Atlantic minke whales. Important behaviours such as feeding and nursing were observed, and most species (including North Atlantic right whales) were seen during all seasons. Baleen whales overlapped with multiple anthropogenic use areas, and all species, but of particular importance North Atlantic right whales, were sighted outside the spatial and temporal bounds of the Seasonal Management Areas for North Atlantic right whales. These opportunistic data are vital for providing a baseline and context of baleen whales in the New York Bight prior to broad-scale efforts and facilitate interpretation of current and future observations and trends, which can more accurately inform effective management and mitigation efforts. [ABSTRACT FROM AUTHOR]

Humpback whales were not observed off the coast of Gabon until Sep, 1997, but are now regularly seen there, especially in the months of July, August and September. Groups of whales have been killed by offshore pollution linked to extensive petroleum exploitation in West Africa. The humpback whale is known for its eerie songs, and 27-ton whales have been observed jumping completely out of the water.

Rapid changes in the Arctic from shifting climate and human use patterns are affecting previously reported distributions and movements of marine mammals. The underwater soundscape, a key component of marine mammal habitats, is also changing. This study integrates acoustic data, collected at a site in the northern Bering Sea, with information on sound sources to quantify their occurrence throughout the year and identify deviations in conditions and dominant soundscape components. Predictive models are applied to explain variation in sound levels and to compare the relative contributions of various soundscape components. Levels across all octave bands were influenced most strongly by the variation in abiotic environment across seasons. The presence of commercial ships did not have a discernible effect on sound levels at this location and period of time. The occurrence of sources was compared to a second site, where we documented how higher levels of shipping changed that soundscape. This study demonstrated the value of acoustic monitoring to characterize the dominant acoustic features in a soundscape and the importance of preserving soundscapes based on dominant features rather than level of sound. Using a soundscape approach has relevance for protecting marine mammals and for the food security of Alaska Native communities that depend upon them. [ABSTRACT FROM AUTHOR]

The protection of evolutionary processes and maintenance of genetic diversity is necessary for the persistence of biodiversity and ecosystem resilience. The importance of genetic diversity has been reflected in a range of marine policy mechanisms, and the genetic 'toolbox' has great potential to support marine protection and marine spatial planning (MSP) at multiple scales. Despite scientific advances in the application of genetics in marine protection and management, systematic integration of genetic information has been generally lacking, primarily due to a knowledge and communication disconnect between geneticists and the marine policy and management community.To meet these outstanding needs, a 'geospatial genetics' approach to spatially map species‐specific genetic data and associated information in a way that can be readily integrated by practitioners into marine protection and MSP decisions was developed. Techniques to derive geospatial genetic data layers, which can be viewed and mapped alongside other kinds of spatial data commonly used by conservation practitioners, hold promise for increasing the accessibility of genetic data to support policy decisions more fully.While applicable to many mobile and sessile taxa, an initial focus was placed on marine mammals, and the approach was developed and refined through a series of international meetings and published papers, as well as the development of interactive, expert‐reviewed case studies hosted on the MSP tool SeaSketch.Outcomes of the work to date are currently serving in the policy arena by informing the identification of Important Marine Mammal Areas, an initiative led by the IUCN Marine Mammal Protected Areas Task Force to apply criteria to identify marine mammal habitats across the world's ocean, seas and relevant inland waters through a standardized process.It has become clear that geospatial genetics has great potential to foster increased collaboration among an intersectional community of geneticists, spatial ecologists, and practitioners. This increased opportunity for dialogue and cooperation will help ensure that evolutionary processes are factored into marine protection and MSP processes, and potentially for freshwater and terrestrial systems. [ABSTRACT FROM AUTHOR]

The New York Bight (NYB) is one of the busiest waterways along the US East Coast, and has recently seen an apparent increase in baleen whale presence. With growing anthropogenic pressures, a better understanding of their distribution and behaviour is needed. Encounter rates (sightings km−1) and behaviour of humpback (Megaptera novaeangliae), fin (Balaenoptera physalus) and minke (Balaenoptera acutorostrata) whales were obtained from dedicated non-systematic small vessel surveys conducted from May–November 2017–2019 in previously under-surveyed coastal areas of the NYB. Humpback whales were the most frequently sighted species, and their distribution in the NYB varied significantly by region and season. Within the mid-shelf region (10–60 km from shore), sightings of all species were generally concentrated spatially and temporally in mixed-species aggregations where feeding on sand lance (Ammodytes spp.) was observed. In the nearshore region (<10 km from shore), sightings of all species were more dispersed and typically occurred in close proximity to Atlantic menhaden (Brevoortia tyrannus). Humpback whales were commonly observed lunge feeding on these prey patches. The prevalence of foraging behaviour throughout the study area supports the hypothesis that the NYB may be an important supplementary feeding area for some species. Encounter rates were generally higher in areas overlapping with anthropogenic activity, suggesting that whales may be particularly vulnerable to anthropogenic impacts in the NYB. The observed species distribution patterns and importance of the NYB as a foraging habitat for baleen whales provides valuable information for the development of new baselines and best management practices within this heavily urbanized region. [ABSTRACT FROM AUTHOR]

Although humpback whale vocalizations can occur above the 1 kHz Nyquist frequency, this sampling rate is sufficient for inferring long-term patterns of hourly presence due to the amount of low-frequency energy in humpback song and calls (Murray et al., 2014). Humpback whale songs were detected March through May (2008) and December through February (2008-2009), a period which extends into the traditional winter breeding season of North Atlantic humpback whales. Repertoire and classification of non-song calls in Southeast Alaskan humpback whales (Megaptera novaeangliae). Humpback whales ( I Megaptera novaeangliae) i are well-known for their long migrations, strong maternal site-fidelity, and their striking vocalization patterns called "songs" (Katona & Beard, 1990; Payne & McVay, 1971). [Extracted from the article]

Declines in Arctic sea ice cover are influencing the distribution of protected endemic marine mammals, many of which are important for local Indigenous Peoples, and increasing the presence of potentially disruptive industrial activities. Due to increasing conservation concerns, we conducted the first year‐round acoustic monitoring of waters off Gambell and Savoonga (St. Lawrence Island, Alaska), and in the Bering Strait to quantify vocalizing presence of bowhead whales, belugas, walruses, bearded seals, and ribbon seals. Bottom‐mounted archival acoustic recorders collected data for up to 10 months per deployment between 2012 and 2016. Spectrograms were analyzed for species‐typical vocalizations, and daily detection rates and presence/absence were calculated. Generalized additive models were used to model call presence as a function of time‐of‐year, sea surface temperature, and sea ice concentration. We identified seasonality in call presence for all species, corroborating previous acoustic and distribution studies, and identified finer‐scale spatiotemporal distribution via occurrence of call presence between different monitoring sites. Time‐of‐year was the strongest significant effect on call presence for all species. These data provide important information on Arctic endemic species' spatiotemporal distributions in biologically and culturally important areas within a rapidly changing Arctic region. [ABSTRACT FROM AUTHOR]

Population delineation is vital for effectively managing and protecting populations of all at‐risk species. Population boundaries of Southern Hemisphere humpback whales on their breeding and feeding grounds have not been fully resolved. A number of methods have been used to delineate breeding stocks of Southern Hemisphere humpbacks, but ecological characteristics determined via stable isotope analysis provide valuable information to contrast other data sources.In this study, stable isotope analysis is used to investigate potential separation of humpback whale populations on Southern Hemisphere feeding grounds as evidenced by carbon and nitrogen isotope values in their skin as proxies of diet.One hundred samples of whale skin obtained from biopsies in sampling localities off the coasts of Gabon, Mayotte (Mozambique Channel), and Madagascar were analysed for carbon (δ13C) and nitrogen (δ15N) stable isotope ratios. The results showed a statistically significant difference in the mean δ15N values for whales between the populations from Gabon and Madagascar (7.0 ± 0.1‰ and 7.6 ± 0.1‰), and Gabon and Mayotte (7.6 ± 0.1‰ and 7.2 ± 0.1‰), indicating that these breeding stocks are potentially visiting different areas of the feeding grounds outside of the breeding season.The results from this study indicate that at least some breeding stocks may show fidelity to separate feeding areas and do not widely mix with individuals from other breeding stocks while feeding. [ABSTRACT FROM AUTHOR]

Describes the existing legislative environment shaping the U.S. federal government's approach to Japanese scientific and technical information, and compares this to the scientific and technical information infrastructure in Japan. Policy options for the United States are presented and evaluated, and recommendations for a federal information policy are made. (CLB)

The author recounts his experiences observing humpback whales along Africa's western and eastern coasts and around the island of Madagascar. Conservation efforts include renewing the Indian Ocean Whale Sanctuary, providing training to Malagasy scientists and students, and networking with regulatory authorities and ecotourism operators.

Higher education institutions' (HEI) have begun to develop decision support system data dashboards (DSS‐DD) to improve the data‐informed decision making practices of institutional decision makers. This qualitative study examines the practices of decision makers as they engage with DSS‐DD at a large U.S. Midwestern university and uncovers the socio‐technical characteristics that lead to limited or non‐use of dashboards. To examine these practices and characteristics, this study presents a framework grounded in socio‐technical interaction networks from social informatics and sociomateriality from information systems that explores the socio‐technical practices of users within organizations, while acknowledging the impact of the users' socio‐technical contexts on their DSS‐DD practices. The results show that during the design and implementation phases of these dashboards the institutional contexts that the dashboards are meant to inform are often ignored; and that as users interact with these systems they develop unintended and shadow practices that lead to limited or non‐use of the dashboards for decision making purposes. Additionally, the study finds that users' practices are influenced by their local socio‐technical networks, which includes their prior experiences using institutional data, other actors within their institutional unit, and the political and social contexts which shape the users' decision making behavior and data‐use practices. [ABSTRACT FROM AUTHOR]

Cetaceans can serve as sentinel species in marine environments as long-lived, apex predators that can concentrate environmental contaminants with potential health consequences. Thus, monitoring the well-being of these species may provide an additional indicator of ecosystem health. In cetaceans, one method for assessing individual and population health is by examining skin conditions. For decades, skin lesions have been increasingly documented in coastal populations of bottlenose dolphins (Tursiops spp.) worldwide. Lesion presence can indicate diminished health and may reflect environmental stressors. Herein, we document the prevalence of epidermal lesions/marks in bottlenose dolphins from the waters off New York and New Jersey during their seasonal presence from spring to fall. Photographs of distinct individuals sighted from May to October 2017 to 2021 were compiled into a catalog, and skin lesions were categorized and counted. Annually, the lowest skin lesion prevalence was in 2021 (p = 0.31), and the highest was in 2017 (p = 0.81). By month, prevalence generally decreased from spring to fall. Overall lesion prevalence in this population was higher than reported estimates for other populations in the coastal waters of the United States. The five most common categories were cloudy white spots, dark spots, white amorphous lesions, tattoo lesions, and dark fringe lesions; and the three most common groups were potentially pathogenic lesions, hypopigmentation, and rake mark-associated potentially pathogenic lesions. Some of the observed lesions have been associated with viral infections that may be exacerbated by environmental stressors. This research establishes an important baseline for further studies into bottlenose dolphin population health in and around the New York--New Jersey Harbor Estuary, particularly given the continued expansion of anthropogenic activities, including those related to forthcoming offshore wind development. [ABSTRACT FROM AUTHOR]

Early 'Discovery mark' data together with recent photo-identification, acoustic, genetic and satellite-radio tag data revealed linkages between humpback whales migrating from breeding grounds (C) off East Africa and the Area III feeding area, from Western Australian breeding grounds (D) and the Antarctic Area IV feeding area and the East Australian breeding grounds (E1) and Antarctic Area V feeding area. These data also revealed low levels of intermingling between (E1) and (D) humpback whales in the Antarctic Area IV feeding area consistent with these being separate populations. Greenpeace photographed the ventral tail flukes of 30 individual humpback whales in the Antarctic Area IV feeding area (70°E-130°E) from 2 to 9 January 2008, between 62°47'S and 64°14'S latitude and 80°00'E and 112°57'E longitude. Comparisons of the Antarctic Area IV Greenpeace fluke catalogue (n = 30) with existing reconciled fluke catalogues from East Africa (n = 842), Western Australia (n = 1,558) and Eastern Australia (n = 1,964), yielded no photo-identification matches. An analysis of the frequencies of whales seen and not seen in Antarctica, East Africa, Western Australia and Eastern Australia relative to the frequencies expected to have been seen and not seen, based on the estimated population sizes and the sizes of the catalogues, provided evidence that the Antarctic whales photographed are from a different population to the East African and East Australian populations. There was weak evidence supporting the hypothesis that the Antarctic whales are from the Western Australian population but insufficient data were available to determine a clear outcome. A comparison of the Antarctic Area IV Greenpeace catalogue (n = 30) with other existing African, Indian Ocean, Western and Eastern Australian and/or Antarctic catalogues, together with increased sampling across the humpback whale feeding season in Antarctica and along the Western and Eastern Australian coastline during their winter migration, is likely to provide further evidence of the migratory destination of these humpback whales. It will also add to our limited knowledge of the extent of population overlap within the Antarctic Area III, IV and V feeding areas. [ABSTRACT FROM AUTHOR]

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 < 0.05) and female fidelity to breeding areas, in line with current understanding of the drivers of broadscale population structure. Consistent with previous studies, the Arabian Sea breeding stock was highly genetically differentiated ( FST 0.034-0.161; P < 0.01 for all comparisons). However, the breeding stock boundary between west South Africa and east Africa was more porous than expected based on genetic differentiation, cluster and geneflow analyses. Instances of male fidelity to breeding areas and relatively high rates of dispersal for females were also observed between the three substocks in the western Indian Ocean. The relationships between demographic units and current management boundaries may have ramifications for assessments of the status and continued protections of populations still in recovery from commercial whaling. [ABSTRACT FROM AUTHOR]

The article discusses the common nonsong social calls of humpback whales recorded off northern Angola, southern Africa. Topics include passive acoustic monitoring using remote autonomous recorders as a proven method for establishing information on the diversity and distribution of cetacean species, Humpback whales (Megaptera novaeangliae) as one of the most frequently sighted species off northern Angola, and lack of rhythmic and continuous pattern of song in social calls.

The article presents data of one of a multiyear series of marine mammal line-transect surveys in the eastern tropical Pacific with information on sighting data, identification photographs, and biopsies of blue whales. A proposal declaring the Galapagos region as a wintering destination of the eastern South Pacific population (ESP) blue whale population is outlined. The critical role of identifying habitat areas for the implementation of marine protected area (MPA) networks is also tackled.

Arctic animals face dramatic habitat alteration due to ongoing climate change. Understanding how such species have responded to past glacial cycles can help us forecast their response to today's changing climate. Gray whales are among those marine species likely to be strongly affected by Arctic climate change, but a thorough analysis of past climate impacts on this species has been complicated by lack of information about an extinct population in the Atlantic. While little is known about the history of Atlantic gray whales or their relationship to the extant Pacific population, the extirpation of the Atlantic population during historical times has been attributed to whaling. We used a combination of ancient and modern DNA, radiocarbon dating and predictive habitat modelling to better understand the distribution of gray whales during the Pleistocene and Holocene. Our results reveal that dispersal between the Pacific and Atlantic was climate dependent and occurred both during the Pleistocene prior to the last glacial period and the early Holocene immediately following the opening of the Bering Strait. Genetic diversity in the Atlantic declined over an extended interval that predates the period of intensive commercial whaling, indicating this decline may have been precipitated by Holocene climate or other ecological causes. These first genetic data for Atlantic gray whales, particularly when combined with predictive habitat models for the year 2100, suggest that two recent sightings of gray whales in the Atlantic may represent the beginning of the expansion of this species' habitat beyond its currently realized range. [ABSTRACT FROM AUTHOR]

A clear understanding of population structure is essential for assessing conservation status and implementing management strategies. A small, non-migratory population of humpback whales in the Arabian Sea is classified as “Endangered” on the IUCN Red List of Threatened Species, an assessment constrained by a lack of data, including limited understanding of its relationship to other populations. We analysed 11 microsatellite markers and mitochondrial DNA sequences extracted from 67 Arabian Sea humpback whale tissue samples and compared them to equivalent datasets from the Southern Hemisphere and North Pacific. Results show that the Arabian Sea population is highly distinct; estimates of gene flow and divergence times suggest a Southern Indian Ocean origin but indicate that it has been isolated for approximately 70,000 years, remarkable for a species that is typically highly migratory. Genetic diversity values are significantly lower than those obtained for Southern Hemisphere populations and signatures of ancient and recent genetic bottlenecks were identified. Our findings suggest this is the world's most isolated humpback whale population, which, when combined with low population abundance estimates and anthropogenic threats, raises concern for its survival. We recommend an amendment of the status of the population to “Critically Endangered” on the IUCN Red List. [ABSTRACT FROM AUTHOR]

This article discusses the passing of a new whale-watching law in Madagascar in order to further protect humpback whales. Topics include wildlife conservation and ecotourism.

The taxonomy of the humpback dolphin genus Sousa has been controversial and unsettled for centuries, but recent work indicates that there are several valid species. A review of multiple lines of evidence from skeletal morphology, external morphology, coloration, molecular genetics, and biogeography, in combination provides strong support for the recognition of four species of Sousa. These include S. teuszii (Kükenthal, 1892), a species with uniform gray coloration and a prominent dorsal hump, which is found in the Atlantic Ocean off West Africa. The species S. plumbea (G. Cuvier, 1829) has similar external appearance to S. teuszii, but has a more pointed dorsal fin. It occurs in the Indian Ocean from South Africa to Myanmar (Burma). The original taxon, S. chinensis (Osbeck, 1765), is reserved for the species that has a larger dorsal fin with no prominent hump, and largely white adult coloration. It ranges from eastern India to central China and throughout Southeast Asia. Finally, we describe a new species of Sousa, the Australian humpback dolphin, which occurs in the waters of the Sahul Shelf from northern Australia to southern New Guinea. It has a lower dorsal fin, more extensive dark color on the body, and a dorsal 'cape.' It is separated from the Indo-Pacific humpback dolphin by a wide distributional gap that coincides with Wallace's Line. [ABSTRACT FROM AUTHOR]