Cetacean Conservation Research Articles

An Online Survey of Public Knowledge, Attitudes, and Perceptions Toward Whales and Dolphins, and Their Conservation

In 2015, an online survey was conducted to investigate public attitudes and perceptions toward key cetacean (whale, dolphin, and porpoise) conservation and 'hot topic' issues such as legislative protection and whaling (n=858). The vast majority of the participants in this study indicated their permanent residence was the United States (n=577) or India (n=251). Perceptions of participants on the conservation priority of cetacean species did not match with the factual IUCN status, where most participants assumed that the larger and more charismatic whales (blue whale, 24.01%; humpback whale, 22.14%; and killer whale, 23.43%) were more endangered or more to conserve than the small cetacean species such as the Vaquita or Hector's dolphin. Additionally, 39.74% of participants indicated the bottlenose dolphin was the most to conserve. More members of the public highlighted non-existent (fake) species (e.g. pygmy short-fined whale, lump-headed dolphin, and majestic spotted dolphin) as being of conservation concern than certain species of actual genuine concern. The majority of participants considered dolphins and whales to be under protected or only slightly protected (29.95%; 41.96%, respectively) and expressed that marine mammal conservation laws and policies were very or important (47.43%; and 37.88%, respectively). In addition, 86.83% of participants expressed opposition to the hunting of dolphins and whales (57.93% strongly opposed and 28.90% opposed); however, only 47.44% of participants were aware that several countries are still involved in whaling. A lack of awareness of the conservation status of whales and dolphins and continued whaling activities suggests that greater outreach to the public about the conservation status of whale and dolphin species is needed.

An overview of cetacean stranding around Hainan Island in the South China Sea, 1978–2016: Implications for research, conservation and management

The South China Sea (SCS) is known to support diverse cetacean species, yet their stranding information has not been well documented. To fill this knowledge gap, available records on cetacean stranding around Hainan Island in the SCS from 1978 to 2016 were collected and overviewed. In total, 112 records were obtained. Among them, 19 records involved 19 baleen whales (5 mysticeti species) and 93 records involved 134 toothed whales (12 odontoceti species). More stranding events occurred in the waters along the east coast than in the waters along the west coast, which was especially true for toothed whales stranding events. This may reflect the distribution patterns of cetaceans around Hainan Island. The spatial distribution of stranding events might be driven by different oceanographic features between the east and west offshore waters of the Hainan Island. The number of stranding events increased gradually from 1978 to 2000 and more rapidly from 2000 to 2016, which is likely due to both increasing public attentions and increasing anthropogenic activities within the SCS in recent decades. Stranding events were recorded throughout the year but peaked in spring (p = 0.016). In sum, cetacean stranding events occurred rather frequently around Hainan Island. The establishment of a regional stranding network in the SCS is conducive for further research, conservation and management of cetaceans in this region. More scientific data about the survival status of cetaceans and threats to them in the SCS are also needed.

Thermal Imaging and Biometrical Thermography of Humpback Whales

Determining species distributions through time and space remains a primary challenge in cetacean science and conservation. For example, many whales migrate thousands of kilometers every year between remote seasonal habitats along migratory corridors that cross major shipping lanes and intensively harvested fisheries creating a dynamic spatial and temporal context that conservation decisions must take into account. Technological advances enabling automated whale detection have the potential to dramatically improve our knowledge of when and where whales are located, presenting opportunities to help minimize adverse human-whale interactions. Using thermographic data we show that near-horizontal (i.e. high zenith angle) infrared images of humpback whale (Megaptera novaeangliae) blows, dorsal fins, flukes and rostrums record similar magnitude brightness temperature anomalies relative to the adjacent ocean surface. Our results demonstrate that these anomalies are similar in both low latitude and high latitude environments despite a ~16°C difference in ocean surface temperature between study areas. We show that these similarities occur in both environments due to emissivity effects associated with oblique target imaging, rather than differences in cetacean thermoregulation. The consistent and reproducible brightness temperature anomalies we report provide important quantitative constraints that will help facilitate the development of transient temperature anomaly detection algorithms in diverse marine environments. Thermographic videography coupled with laser range finding further enables calculation of whale blow velocity, demonstrating that biometrical measurements are possible for near-horizontal datasets that otherwise suffer from emissivity effects. The thermographic research we present creates a platform for the delivery of 3 important contributions to cetacean conservation: 1) non-invasive species-level identifications based on whale blow shapes and velocities recorded by infrared videography; 2) reduced ship-strike rates through automated thermographic cetacean detection systems deployed in high traffic areas; 3) monitoring the spatial and temporal distributions of endangered animals in remote habitats.

Multi-stakeholder collaboration yields valuable data for cetacean conservation in Gamba, Gabon

Private industry, the Government of Gabon and two international NGOs collaborated to conduct marine surveys off the coast of Gabon, Central Africa. Surveys addressed multiple objectives of surveillance and monitoring, the documentation of the distribution of and threats to the marine megafauna, and capacity-building among government agents and local early-career scientists. During 22 days of survey effort over a two-year period, observers documented humpback whales Megaptera novaeangliae, bottlenose dolphins Tursiops truncatus, Atlantic humpback dolphins Sousa teuszii and common dolphins Delphinus delphis. Humpback whale presence was limited to the months of July to November. Bottlenose dolphins were present year-round and photo-identification of individuals indicated a closed, resident population, with an abundance estimate of 118 (CV = 21.6%, 95% CI 78–180). Small open-decked fishing vessels with gillnets were observed concentrated around river mouths within 2 km of shore, while commercial trawlers were at least 10 km offshore; all were confirmed to be registered and legal. Observations of marine turtles, flocks of marine birds, and floating logs and other debris were sparse. This multi-stakeholder collaboration to conduct a marine survey can serve as an effective model by which funding and logistic support from private industry paired with technical expertise from NGOs and academic institutions can benefit marine and coastal conservation.

Spatio-temporal distribution and habitat preferences of cetaceans in Algoa Bay, South Africa

Increasingly, baseline knowledge of habitat preferences and movement patterns of marine species is required to inform anthropogenic developments. The aim of this study was to determine baseline spatio-temporal distribution and habitat preference of cetaceans in the coastal waters of Algoa Bay. Areas of potential conflict with anthropogenic activities were also assessed. Monthly sea-based surveys were conducted between June 2008 and May 2011. A total of 500 cetacean sightings comprising six species were recorded in 106 surveys. Tursiops aduncus (Indo-Pacific bottlenose dolphin), Sousa plumbea (Indian Ocean humpback dolphin), Delphinus capensis (long-beaked common dolphin) and Balaenoptera brydei (Bryde's whale) were observed year-round, while Eubalaena australis (southern right whale) and Megaptera novaeangliae (humpback whale) were recorded from May to December. A large portion of sightings were associated with a Marine Protected Area and shipping zones. Eubalaena australis, T. aduncus and S. plumbea were found inshore (water depths < 12 m), while the other species were associated with deeper waters. Tursiops aduncus were most commonly seen (233 sightings). Megaptera novaeangliae were sighted often in austral winter, with 113 sightings. Only nine D. capensis sightings were recorded. Spatial distributions of species were corrected for search effort to identify habitat preferences. A number of key observations were made, including opportunistic foraging in M. novaeangliae, and the expansion of nursery grounds for E. australis, to include Algoa Bay. Four preferred habitat areas are proposed, providing important information for conservation and management of cetaceans in Algoa Bay. The spatial approach can be used to inform future relevant management decisions elsewhere.

Cetacean conservation in the Mediterranean and Black Seas: Fostering transboundary collaboration through the European Marine Strategy Framework Directive

The European Marine Strategy Framework Directive (MSFD) aims at implementing a precautionary and holistic ecosystem-based approach for managing European marine waters. Marine mammals are included as a functional group for the assessment and reporting under Descriptor 1-Biodiversity. Conservation of mobile marine megafauna such as cetaceans requires transboundary cooperation, which the MSFD promotes through regional instruments, such as the Regional Sea Conventions and other regional cooperation structures such as ACCOBAMS (Agreement on the Conservation of Cetaceans of the Black Sea, Mediterranean Sea and Contiguous Atlantic Area). A questionnaire survey and an exploratory analysis of MSFD implementation in the Mediterranean and Black Seas were conducted. The analysis revealed (i) the saliency of cetacean conservation, and (ii) heterogeneity among countries in the implementation of the MSFD that may hinder transboundary collaboration. ACCOBAMS can stimulate collaboration among scientists involved in cetacean monitoring and can foster transboundary initiatives that would align with MSFD objectives.

POSTMORTEM FINDINGS IN CETACEANS FOUND STRANDED IN THE PELAGOS SANCTUARY, ITALY, 2007-14.

Between 2007 and 2014, 83 cetaceans were found stranded along the Ligurian coast of Italy, in the Pelagos Sanctuary, the largest marine protected area in the Mediterranean basin. Forty-nine (59%) were submitted to complete or partial necropsy, depending on the conservation status of the carcass. Based on gross and histological pathology and ancillary testing, the cause of death was determined and categorized as anthropogenic or natural (i.e., nonanthropogenic) in origin for 33 animals (67%) and of undetermined origin in the remaining 16 (33%). Natural causes of death, accompanied by either poor or good nutritional status, were attributed to 29 animals (59%), whereas four (8%) were diagnosed with an anthropogenic cause of death, consisting of interaction with fishing activities. Infectious and noninfectious disease was the most common cause of death, involving 29 cetaceans (59%). These data are valuable for understanding health and mortality trends in cetacean populations and can provide information for establishing policies for cetacean conservation and management in such an important protected area of the Mediterranean basin.

Whale‐watching trips in Peru lead to increases in tourist knowledge, pro‐conservation intentions and tourist concern for the impacts of whale‐watching on humpback whales

Abstract Since the implementation of the commercial whaling ban in the 1980s, whale‐watching has become the most important economic activity involving whales worldwide. Whale‐watching is promoted as a platform for education and conservation awareness of marine biodiversity. In Peru, where cetacean species are still in jeopardy, whale‐watching may play an important part in promoting the protection of these species. This study aimed to determine the degree of whale‐watching tourists' knowledge regarding cetacean ecology and conservation status and to evaluate if whale‐watching tours could serve as platforms for educating the public and raising conservation awareness. The results of 196 closed‐ended questionnaires and 20 open‐ended interviews conducted before and after whale‐watching tours, during the humpback whale season (winter–spring 2014) in northern Peru, revealed an overall lack of knowledge concerning the presence of species of cetaceans in Peruvian waters and threats to marine biodiversity. However, after the whale‐watching excursion, participants said they would be more willing to change their behaviour with respect to cetacean conservation and marine environment protection. This study suggests that whale‐watching platforms, when implemented with adequate interpreters, can serve as a source of environmental education and can raise conservation awareness. This is an important conservation strategy to consider in countries, such as Peru, where by‐catch and direct hunting are decimating local cetacean populations.

Testing and deployment of C-VISS (cetacean-borne video camera and integrated sensor system) on wild dolphins

Multi-sensor biologgers are a powerful method for studying individual behaviors of free-ranging species, yet the challenges of attaching non-invasive biologgers to agile, fast-moving marine species have prohibited application of this technique to small (<5 m) cetaceans. Integration of video cameras into such biologgers is critical to understanding behavior from the animal’s perspective; however, this technique has not been applied to small cetaceans. We examined the feasibility of remotely deploying a cetacean-borne video camera and integrated sensor system (“C-VISS”) on small cetaceans. We deployed C-VISS on eight free-swimming dusky dolphins (Lagenorhynchus obscurus) off New Zealand (42°25′15″S 173°40′23″E) from December 2015 to January 2016, collecting a total of 535 min of video footage (average = 66.8 ± 91.10 SD, range 9–284). Dolphins were observed to show limited reactions to biologger attachment attempts and deployments. Social and environmental parameters derived from video footage include conspecific body condition, mother-calf spatial positioning, affiliative behavior, sexual behavior, sociability, prey, and habitat type. The ability to record behavioral states and fine-scale events from the individual’s perspective will yield new insights into the behavior, socioecology, conservation, rehabilitation, and welfare of small cetaceans.

Modelling cetacean distribution and mapping overlap with fisheries in the northeast Atlantic

Improving our knowledge of cetacean distribution and habitat use are key if we are to effectively ensure good conservation status for these species. Often however, sufficient data are lacking, inhibiting conservation efforts of many species. This study aims to combine historical datasets to generate habitat suitability models and thus maps, for eight species of cetacean regularly sighted in the Irish portion of the northeast Atlantic; fin whale, minke whale, pilot whale, sperm whale, white-sided dolphin, bottlenose dolphin, Risso's dolphin and white-beaked dolphin. Habitat suitability models were developed using MaxEnt modelling software for a range of environmental factors; sea-surface temperature, mixed layer depth, depth, slope, chlorophyll a concentration, sea surface salinity, distance to the 200 m contour. We predicted species exposure to fishing gears by integrating habitat suitability models with information on fishing vessel activities within the study area. The main predictors of habitat suitability for all species were topographic variables, particularly depth and slope, highlighted by two areas of high species richness around areas of topographic heterogeneity, along the continental shelf and on the west coast. Combining habitat models with fishing activity, indicated areas of high exposure off the north and south coasts and in an area known as the Porcupine Bank off the west coast. These results are valuable for conservation and management of cetaceans and fisheries in the study area. Methods can be easily adjusted to allow replication for other species and other anthropogenic activities. We recommend future effort focuses on winter months to fill in the gaps on year round cetacean distribution.

The International Whaling Commission—Beyond Whaling

Since its establishment in 1946 as the international body intended to manage whaling, the International Whaling Commission (IWC) has expanded its areas of interest to ensure the wider conservation of whales. Several key conservation topics have been taken forward under its auspices including climate change, chemical and noise pollution, marine debris and whale watching. Work on each of these topics at the IWC has grown substantially since the 1990s and remains ongoing. Important developments were the establishment of the Standing Working Group on Environmental Concerns in 1996 and the IWC’s Conservation Committee in 2003. Trying to address this diverse set of issues is obviously a challenge but will be necessary if the long term conservation of cetaceans is to be achieved. Through research, workshops, resolutions and collaboration with other organisations, the IWC has advanced both the understanding of the various issues and the means to manage them with increasing effectiveness. The IWC is likely to remain on the forefront of continuing efforts to address these, and other, conservation concerns and ensure the continued viability of cetacean populations around the globe.

What gets left behind for future generations? Reproduction and the environment in Spey Bay, Scotland

What gets left behind for future generations? Reproduction and the environment in Spey Bay, Scotland

Effects of vessel traffic on relative abundance and behaviour of cetaceans: the case of the bottlenose dolphins in the Archipelago de La Maddalena, north-western Mediterranean sea

Many studies have shown that vessel traffic has both long- and short-term negative effects on marine mammals. Although there has been a great expansion of recreational vessel traffic in the Mediterranean Sea in recent decades, few studies focused on this problem. Here, Bayesian models were used to explore the influence of vessel traffic on behaviour and relative abundance patterns of bottlenose dolphin in the Archipelago de La Maddalena (Italy), a coastal area included within the Pelagos Sanctuary. Results showed that season, moon phase and presence of calves had an effect on the number of adult dolphins per sighting, and that there were differences in occurrence in the sub-areas. On the contrary, the number of vessels was negatively related to the number of adult dolphins and their mean dive intervals. In particular, when more than three recreational boats were present in the area, dolphins surfaced more frequently per unit time and behaviours such as feeding and socializing were not detected. On the contrary, longer mean dive was found when fishing boats were present. Our results provide additional support for the need to consider disturbance such as vessel traffic in management plans for cetacean conservation.

Spatial and Temporal Variations in the Occurrence and Foraging Activity of Coastal Dolphins in Menai Bay, Zanzibar, Tanzania.

Understanding temporal patterns in distribution, occurrence and behaviour is vital for the effective conservation of cetaceans. This study used cetacean click detectors (C-PODs) to investigate spatial and temporal variation in occurrence and foraging activity of the Indo-Pacific bottlenose (Tursiops aduncus) and Indian Ocean humpback (Sousa plumbea) dolphins resident in the Menai Bay Conservation Area (MBCA), Zanzibar, Tanzania. Occurrence was measured using detection positive minutes. Inter-click intervals were used to identify terminal buzz vocalisations, allowing for analysis of foraging activity. Data were analysed in relation to spatial (location) and temporal (monsoon season, diel phase and tidal phase) variables. Results showed significantly increased occurrence and foraging activity of dolphins in southern areas and during hours of darkness. Higher occurrence at night was not explained by diel variation in echolocation rate and so were considered representative of occurrence patterns. Both tidal phase and monsoon season influenced occurrence but results varied among sites, with no general patterns found. Foraging activity was greatest during hours of darkness, High water and Flood tidal phases. Comparisons of echolocation data among sites suggested differences in the broadband click spectra of MBCA dolphins, possibly indicative of species differences. These dolphin populations are threatened by unsustainable fisheries bycatch and tourism activities. The spatial and temporal patterns identified in this study have implications for future conservation and management actions with regards to these two threats. Further, the results indicate future potential for using passive acoustics to identify and monitor the occurrence of these two species in areas where they co-exist.

Site‐fidelity and movement patterns of bottlenose dolphins (Tursiops truncatus) in central Argentina: essential information for effective conservation

Abstract The effectiveness of conservation measures such as marine protected areas (MPAs) for the conservation of cetaceans is determined by how well their home range or critical habitat is covered. The present study seeks to provide information on the site‐fidelity and movement patterns of individual bottlenose dolphins (Tursiops truncatus) in central Argentina. Between 2007 and 2013, photo‐identification data of bottlenose dolphins were collected in four study sites some 90–200 km apart from each other along the central Argentinean coast. Results show long‐term site‐fidelity (over 5 years) in one of the study areas. Re‐sighting rates further suggest the existence of different sub‐populations of bottlenose dolphins, but also confirm some connectivity (with movements over 200–290 km) and thus potential for gene flow within the region. Considering the population declines of bottlenose dolphins in Argentina, information on site‐fidelity and movement patterns will be of value to improve the effectiveness of existing MPAs for the conservation of the species as well as prioritizing areas for increased research. Copyright © 2016 John Wiley &amp; Sons, Ltd.

Cetacean Strandings in Korean Waters

Abstract: The spatial and temporal distribution pattern of stranded cetaceans in Korean waters was investigated for the conservation and management of cetaceans in this area. A total of 154 cetacean stranding events consisting of 12 species were recorded in Korean waters from 1997 to 2004 by the Korea Coast Guard. A total of 4 species, the minke whale (Balaenoptera acutorostrata) (n = 43), Unless porpoise (Neophocaena asiaeorientalis) (n = 43), Stejneger's beaked whale (Mesoplodon stejnegeri) (n= 15), and common dolphin (Delphinus delphis) (n= 11), accounted for 73% of the stranded cetaceans. The majority of stranding events took place in the East Sea (n = 99; 64%) followed by the Korea Strait (n = 48; 31%) and the Yellow Sea (n = 7; 5%). The hot spots of stranding events in Korean waters were Pohang (18%), Busan (9%), and Goseong (8%). The number of stranding events increased following the establishment of the bycatch/stranding reporting system in 1997, with a steep increase in the number of stranding ev...

Cetacean diversity, common occurrence and community importance in Fijian waters

Fiji has demonstrated a strong commitment to cetacean conservation via national, regional and international plans and agreements. To provide baseline information in support of these efforts, this paper provides an updated listing of cetacean species found in Fijian waters and identifies locations where cetaceans have been noted on a consistent basis. Information for this review was sourced from peer-reviewed publications, field reports, historical whaling records, national consultations, anecdotal and opportunistic sources, as well as a national database held by the Fiji Government’s Department of Fisheries. Reliable and recent records were confirmed for 10 cetacean species in Fijian waters. In addition, less reliable records and regional species’ information provides support for the occurrence of at least 14 additional species or groups of similar-looking species that could not be identified more specifically. Thirteen hotspot areas within the Fiji Economic Exclusive Zone were preliminarily identified as being particularly important for cetaceans, including numerous sites within the Vatu-i-Ra and Lomaiviti passages and surrounding waters. Issues with the available data include uneven coverage, inherent biases within available sources, and difficulties with species identification and verification in some cases. Nevertheless, it is hoped that this review will provide a reference point from which to move forward with cetacean management and conservation efforts in Fiji.

Occurrence, distribution and behaviour of Bryde's whales (Cetacea: Mysticeti) off south-east Brazil

Bryde's whales are among the lesser known balaenopterids found in Brazilian waters, as well as globally. At the beginning of this project, only occasional sightings of this species were identified off the coast of São Paulo State. In this paper, we present the results of our investigations into the occurrence and behaviour of Bryde's whales along the São Paulo coast, both inside and outside the Marine State Park of Laje de Santos, as a contribution to biological and behavioural knowledge of Bryde's whales under the conservation scope. Sighting surveys were conducted from January 2003 to July 2005 in coastal and oceanic areas. During the survey, 42 sightings were made, totalling 71 individuals, between the isobaths of 20 and 3000 m. Sightings and individual rates were higher in coastal areas during the summer season. Different kinds of behaviour were observed in coastal and oceanic areas. At the 1200 m isobath, notable social interactions were observed in which four adult individuals performed breaching – the first report of this behavioural pattern for Brazil. Results suggest that Bryde's whales possibly use coastal areas for feeding and may migrate to oceanic areas for breeding, thus providing important aspects that must be considered for the proper management of Marine Protected Areas and for oceanic areas, especially considering the intensive and continuous increase of oil and gas exploitation activities in those areas. Data reported here, therefore, constitute a significant contribution in Bryde's whale research and to cetacean conservation efforts in Brazil.

Cetaceans and tuna purse seine fisheries in the Atlantic and Indian Oceans: interactions but few mortalities

Fisheries bycatch is considered to be one of the most significant causes of mortality for many marine species, including vulnerable megafauna. In the open ocean, tuna purse seiners are known to use several cetacean species to detect tuna schools. This exposes the cetaceans to encirclement which can lead to incidental injury or death. While interactions between fishers and cetaceans have been well documented in the eastern tropical Pacific Ocean, little is known about these interactions and potential mortalities in the tropical Atlantic and Indian Oceans. Here, we provide the first quantification of these interactions in both oceans by analyzing a large database of captain’s logbooks (1980 to 2011) and observations collected by onboard scientific observers (1995 to 2011). Distribution maps of sightings per unit effort highlighted main areas of relatively high co-occurrence: east of the Seychelles (December to March), the Mozambique Channel (April to May) and the offshore waters of Gabon (April to September). The percentage of cetacean-associated fishing sets was around 3% in both oceans and datasets whereas 0.6% of sets had cetaceans encircled. Of the 194 cetaceans encircled in a purse seine net (122 baleen whales, 72 delphinids), immediate apparent survival rates were high (Atlantic: 92%, Indian: 100%). Among recorded mortalities, 8 involved pantropical spotted dolphins Stenella attenuata and 3 involved humpback whales Megaptera novaeangliae. These high survival rates suggest that setting nets close to cetaceans has a low immediate apparent impact on the species involved. Our findings will contribute to the development of an ecosystem approach to managing fisheries and accurate cetacean conservation measures.

Key research questions of global importance for cetacean conservation

Limited resources and increasing environmental concerns have prompted calls to identify the critical questions that most need to be answered to advance conservation, thereby providing an agenda for scientific research priorities. Cetaceans are often keystone indicator spe- cies but also high profile, charismatic flagship taxa that capture public and media attention as well as political interest. A dedicated workshop was held at the conference of the Society for Marine Mammalogy (December 2013, New Zealand) to identify where lack of data was hindering cetacean conservation and which questions need to be addressed most urgently. This paper sum- marizes 15 themes and component questions prioritized during the workshop. We hope this list will encourage cetacean conservation-orientated research and help agencies and policy makers to prioritize funding and future activities. This will ultimately remove some of the current obstacles to science-based cetacean conservation.