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WA shark study questions affect of tagging on animals' feeding ability.

WA shark study questions affect of tagging on animals' feeding ability.

Dead fish, marine animals wash up your favourite Maharashtra beach.

Ongoing research of a dolphin population in south-western Australia has revealed for the first time, a unique cycle in social bonds between adult female bottlenose dolphins, which is leading to informed conservation for the animals.

Ongoing research of a dolphin population in south-western Australia has revealed for the first time, a unique cycle in social bonds between adult female bottlenose dolphins, which is leading to informed conservation for the animals.

Thousands of turtles, marine animals victims of plastic fishing nets polluting Gulf of Carpentaria.

Subsea infrastructure of the oil and gas industry attracts commercial fish species as well as megafauna including sea lions, turtles, sharks and whales. Potential impacts of this attraction, whether positive or negative, are unknown. As part of a pilot study, we deployed acoustic telemetry equipment around offshore infrastructure to assess its effectiveness in detecting tagged marine animals and to gain insights into patterns of megafauna occurrence around these structures. Acoustic receivers were placed around four oil and gas platforms and on two remotely operated vehicles (ROVs) on Australia's North West Shelf. Two whale sharks (Rhincodon typus) tagged in the World Heritage Ningaloo Reef Marine Park were detected at two platforms, North Rankin A and Pluto, located up to 340 km to the northeast. The shark at North Rankin A was detected infrequently and only 15 times over ∼6 weeks. The shark at Pluto was detected each day of the 24-day deployment, in total 4,894 times. Detections at Pluto platform were highest during the day, with peaks at dusk and dawn. Our study indicates that acoustic telemetry around platforms may be an effective method for understanding how marine megafauna utilise these structures. We recommend collaborating with industry to undertake receiver detection range testing to understand the effectiveness of the method. Furthermore, future studies should co-occur with tagging programs at sites like Ningaloo Reef and around the structures themselves to maximise the probability of detecting animals at these sites, thereby improving our understanding of how marine megafauna interact with these structures.

Symbiotic associations between marine animals and sessile invertebrates are a remarkable feature of coral reef ecosystems. However, most studies often concentrate on free-living organisms, which are easier to collect and identify. In contrast, symbiotic animals are frequently overlooked or underestimated because of their small size, hidden lifestyles, and the broad distribution of sibling or cryptic species that are specialized to specific host species (Knowlton, 1993; Horka et al., 2016). Although the uniqueness of these symbiotic relationships is not fully understood, crustacean decapods associate with other macro invertebrates. In particular, various echinoderms are notably common and exhibit astonishing diversity in their morphology, ecology and sexual biology within the tropical Indo-Pacific region (BRUCE, 1976; WILLIAMS, 1984; NG and JENG, 1999; HAYES, 2007; HAYES et al., 2016).

India's coral reefs are home to many stunning marine animals, but they might be gone before we know it.

India's coral reefs are home to many stunning marine animals, but they might be gone before we know it.

Researchers have identified a new species of mysterious beaked whale based on a study of seven animals stranded on remote tropical islands in the Indian and Pacific Oceans over the past 50 years.

Disrupting just one process in the important relationship between microbes and bigger plants and animals that live in ocean floor sediment may have knock-on effects that could reduce the productivity of coastal ecosystems, according to international research published online yesterday in Philosophical Transactions of the Royal Society B.

KENDRAPARA: Ahead of the mass nesting of Olive RIDLEY sea turtles, beaches off Gahirmatha coast have turned into graveyard for these delicate marine animals with thousands of decomposed carcasses spotted along a shoreline.

A juvenile green sea turtle discovered floating in an estuary in Broome has been brought to Murdoch University's Animal Hospital for a CT scan.

The world's animal distribution map will need to be redrawn and textbooks updated, after researchers discovered the existence of 'Australian' species on Christmas Island.

Orcas live in stable, structured social groups. And their survival directly depends on it, as a CNRS and University of La Rochelle research team1 has just demonstrated. Between 1996 and 2002, half of the CROZET Islands orca population was killed off by an illegal fishing operation targeting Patagonian toothfish, with the orcas removing the fish from the line during hauling. The orcas' survival rate has yet to return to its former level. Using data from a photo-identification programme begun in 1987, the scientists were able to show that surviving orcas from a decimated family adopted "erratic" social behaviour, moving from group to group. The weaker these social ties, the greater the animals' likelihood of dying. As these orcas are probably not completely accepted by the new groups they join, they are likely to be given less access to food than the regular members of the social unit-and eventually die. These findings-published in the Proceedings of the National Academy of Sciences (20 May 2019)-are the first to reveal the long-term consequences of events affecting the survival and social organization of a mammalian species.

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.

The silver-lipped pearl oyster, Pinctada maxima, is the primary species used for the culture of pearls in the Indo-Pacific region. The Western Australian fishery relies on wild-caught animals, and as such, knowledge of the status and distribution of P. maxima underpins sustainable management of the fishery. Eighty Mile Beach, in tropical Western Australia, is the key harvest area for P. maxima, with oysters collected by divers to depths of ∼35 m, although there are anecdotal accounts of oysters beyond diving depths. Image-based, and acoustic methods were used to elucidate distribution patterns of P. maxima off Eighty Mile Beach, including data from 862 km2 of multibeam survey and 119 towed video transects spanning an area from the 20 to 100 m contour lines. We quantified habitat characters including depth, substrate, and benthic community composition associated with pearl oyster distribution. Multibeam sonar data was also coupled with towed video data to produce predictive statistical models of P. maxima habitat. We found P. maxima to depths of 76 m, although more than 90% of individuals occurred shallower than 40 m and less than 2% were found deeper than 50 m. Oysters occupied flat, sandy habitats with neighbouring benthic communities of filter feeders (>98% of observations). These results show P. maxima predominantly occurs in depths <40 m, with no evidence that extensive populations extend into deep water in the region.

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

Baitfishes may aggregate around megafauna such as whale sharks (Rhincodon typus) to gain protection from larger predatory fishes. Here, we used videos from deployments of animal-borne cameras on whale sharks and provided by tourism operators at Ningaloo Reef in Western Australia to document large schools of trevally (Carangidae spp.) consuming entire schools of baitfishes (Carangidae spp.) swimming with whale sharks within 2-45 s. These videos showed that small baitfishes are still very vulnerable to predatory fishes when accompanying whale sharks, refuting the hypothesis that whale sharks provide baitfishes shelter from predators. It thus seems more likely that the association between whale sharks and baitfishes may confer other advantages such as reduced costs of locomotion and/or enhanced feeding opportunities for baitfishes rather than protection from predation.

During feeding and burrowing, many epibenthic and infaunal animals bioturbate sediments and form a range of traces called lebensspuren (German for 'life traces'), defined as any type of sedimentary structure produced by a living organism. During a 2020 survey along western Australia in the Gascoyne Marine Park, a distinct trace was observed several times, identical to the 'spider trace' observed in a 2007 survey along eastern Australia, over 4000 km away. The purpose of this brief note is to document and describe the occurrence of this unique and distinctive type of lebensspuren and to discuss ways in which similar observations may be effectively shared to increase our understanding of deep-sea biology.

Large ocean animals can be protected throughout much of their lifecycle by huge Marine Protected Areas (MPAs), new research shows.