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Swimming with humpback whales to be trialled at WA's Ningaloo marine park.

Swimming with humpback whales to be trialled at WA's Ningaloo marine park.

A study by an international team of marine researchers, including The University of Western Australia, has found dolphin survival and reproductive rates suffered a significant decline following a 2011 marine heatwave affecting around 1,000km of Western Australia's coastline.

Marine census planned for coastal waters on March 23.

Assessments of species distributions are crucial for informing conservation and management action. In this study, we used ensemble modelling to explain the distribution of Near Threatened Indo-Pacific (IP) bottlenose dolphins (Tursiops aduncus) in coastal waters at the North West Cape (NWC), Western Australia (WA), an area encompassing a marine protected area (MPA) and adjacent unprotected coastal waters. Analyses used dolphin sighting data collected during boat-based surveys conducted from 2013 to 2015 and 2018 to 2019. Overall, the distribution of IP bottlenose dolphins was best explained by distance to coast (up to 2,000 m) and distance to boat ramp (up to 7,000 m). Areas of high probability of occurrence for dolphins extended from the tip and down the eastern side of the NWC and overlapped with designated sanctuary zones as well as waters beyond the boundaries of the Ningaloo Marine Park (NMP). Distribution and habitat preferences varied slightly with season. In autumn, dolphin distribution was best explained by distance to coast and water depth with a higher likelihood of observing dolphins 1,000-2,000 m from the coast and in water depths of 7-10 m deep. During winter months, distance to coast (1,000-2,000 m) and sea surface temperature (SST) (21.5-23.5°C) were the most important explanatory variables, with presence in coastal lagoons to the west of the NWC more likely than other seasons. During spring, areas of moderate to high probability of dolphin occurrence were mainly located outside the NMP, with marine park zone (outside the NMP and Sanctuary zones within the NMP, the two zones with the highest probability of IP bottlenose dolphin occurrence) and water depth (waters 7-13 m deep) best explaining dolphin distribution. This study highlights the importance of inshore areas of the NWC for IP bottlenose dolphins and the potential vulnerability of this species to increasing and cumulative anthropogenic stressors associated with these areas. Results

Death by noise: Sound of ships kills marine mammals in Mumbai.

An unprecedented marine heatwave had long-lasting negative impacts on both survival and birth rates on the iconic dolphin population in Shark Bay, Western Australia. Researchers at UZH have now documented that climate change may have more far-reaching consequences for the conservation of marine mammals than previously thought.

Seychelles has announced two new Marine Protected Areas covering 210,000 square kilometers of biodiverse ocean waters.

This Cemetery is Dedicated to Marine Life That Has Been Killed by Plastic.

Threatened inshore dolphins and other species need protecting from proposed industrial expansion in Exmouth Gulf - an unprotected habitat adjoining the UNESCO World Heritage Listed Ningaloo Coast and Marine Park, warn experts from Flinders University's Cetacean Ecology, Behaviour and Evolution Lab (CEBEL).

'Screams' could chase away other marine life.

Preventing bycatch of threatened marine megafauna is a challenging task, writes Brian D. SMITH from the Wildlife Conservation Society (WCS), an SOS-Save Our Species grantee, in the Bay of Bengal, Bangladesh. Early one morning WCS researcher Rubaiyat Mansur received a phone call. It was from Sonjoy Kumar DASH, one of the gillnet fishing captains participating in … ↓ Read the rest of this entry...

Preventing bycatch of threatened marine megafauna is a challenging task, writes Brian D. SMITH from the Wildlife Conservation Society (WCS), an SOS-Save Our Species grantee, in the Bay of Bengal, Bangladesh. Early one morning WCS researcher Rubaiyat Mansur received a phone call. It was from Sonjoy Kumar DASH, one of the gillnet fishing captains participating in … ↓ Read the rest of this entry...

Dr. Salvatore CERCHIO is a marine mammal biologist at the New England Aquarium. In November 2015, he went off the grid to study Omura's whales off the coast of Madagascar.

Dr. Salvatore CERCHIO is a marine mammal biologist at the New England Aquarium. In November 2015, he went off the grid to study Omura's whales off the coast of Madagascar.

Large numbers of dugongs, sea snakes and other marine animals disappeared from the UNESCO World Heritage Site Shark Bay, Western Australia, after a heat wave devastated seagrass meadows, according to recently released research.

Adult male sperm whales (Physeter macrocephalus) are long distance runners of the marine realm, feeding in high latitudes and mating in tropical and subtropical waters where stable social groups of females and immatures live. Several areas of uncertainty still limit our understanding of their social and breeding behavior, in particular concerning the potential existence of geographical and/or social fidelities. In this study, using underwater observation and sloughed-skin sampling, we looked for male social fidelity to a specific matrilineal sperm whale group near Mauritius. In addition, we captured a wider picture of kin relationships and genetic diversity of male sperm whales in the Indian Ocean thanks to biopsies of eight individuals taken in a feeding ground near the Kerguelen and Crozet Archipelagos (Southern Indian Ocean). Twenty-six adult male sperm whales were identified when socializing with adult females and immatures off Mauritius. Sloughed-skin samples were taken from thirteen of them for genetic analysis. Long-term underwater observation recorded several noteworthy social interactions between adult males and adult females and/or immatures. We identified seven possible male recaptures over different years (three by direct observation, and four at the gametic level), which supports a certain level of male social fidelity. Two probable first- and thirty second-degree kin relationships were highlighted between members of the social unit and adult males, confirming that some of the adult males observed in Mauritian waters are reproductive. Male social philopatry to their natal group can be excluded, as none of the males sampled shared the haplotype characteristic of the matrilineal social group. Mitochondrial DNA control region haplotype and nucleotide diversities calculated over the 21 total male sperm whales sampled were similar to values found by others in the Indian Ocean. Our study strongly supports the existence of some levels of male sperm whale socia

Despite being the third largest ocean in the world, the Indian Ocean is one of the least explored marine environments. Covering around 20 per cent of the Earth's surface and spanning more than 73 million square kilometres, it's an important channel for over half the world's shipping.

Sri Lanka saves pod of stranded whales.

The Indian Ocean humpback dolphin (Sousa plumbea) is "endangered" with likely less than 500 animals remaining in South African waters. Established in 2016, the SouSA Consortium is a formalised network of scientists and conservationists to combine knowledge and research efforts, and make coordinated decisions with the aim of conserving the species. The first collaborative project collated available photo-identification data in an attempt to refine a national population estimate and investigate movements between research sites. This work was able to identify 250 uniquely marked individuals, with the population divided into the south-coast (Agulhas bioregion) and east-coast (Natal bioregion) populations. Environmental factors almost certainly play a role in the declining numbers of the species in South African waters. However, individual threats and solutions are challenging to identify as the South African marine environment is undergoing significant natural and anthropogenic changes with major shifts in the distribution and numbers of some prey, competitor and predator species. Therefore, we believe that a continued investigation of potential contributing factors and their interaction will take too long, inevitably resulting in another case of documenting extinction. With this in mind, we present the results of a SWOT (Strengths, Weaknesses, Opportunities, and Threats) analysis in an effort to help us identify the next steps to take toward the conservation of humpback dolphins in South African waters. We unanimously conclude that no single cause for the rapid decline of humpback dolphins in South African waters can be identified, and that the cumulative effects of multiple stressors, which are difficult to pinpoint and mitigate, are impacting population numbers. While highlighting the need for continued research, we suggest a shift toward more action-focused conservation efforts, the first concrete steps being the development of a Conservation Management Plan wit