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Marine Life & Conservation

Dolphin Whistles Could Aid Conservation Efforts

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A team of researchers in Italy, Portugal, Spain, France, Britain and the United States has demonstrated that remotely monitoring the acoustical structures of dolphin vocalizations can effectively detect “evolutionarily significant units” of the mammal — distinct populations that may be tracked for prioritizing and planning conservation efforts.

This finding, which has been presented this week at the 167th meeting of the Acoustical Society of America in Providence, Rhode Island, suggests that placing remote acoustical monitoring platforms on ocean buoys and the like may be a viable, low-cost and automated way of monitoring populations of dolphins and rapidly alerting ecologists to the threats that confront them.

“Acoustical changes can be used for constant and continuous monitoring of population belonging to endangered species,” said Elena Papale of the University of Torino, who led the research. “We found that [by remotely monitoring dolphin whistles], it is possible to distinguish between evolutionary significant units.”

The discovery emerged from a large, multinational collaboration that pulled together data from five research groups based in Italy, Portugal, Spain, Britain and France. Those groups were already monitoring dolphins for a number of existing scientific studies. Other groups in the United States collaborated by providing sound analysis equipment. Shepherding all these groups of people and the flood of data they produced was a challenge, Papale said, but the greater challenge was working out how to distinguish the flood of whistles from one group of dolphins from another.

Animal vocalizations have acoustic characteristics that reflect an organism’s genes, its adaptation to ecological conditions and the interactions between their genes and the environment. The differences between groups of dolphins within the same species may be slight and hard to detect however, because morphological features, ecological conditions and socio-behavioral aspects of the creatures influence the structure of whistle. The problem is also a dynamic one, since vocalizations may vary in short time scale.

So at the start of the research, it was not clear whether acoustical analyses alone would be able to tease apart the common threads for given groups of dolphins and differentiate between them.

Papale and her colleagues compared 123 sightings of three dolphin species from the Atlantic Ocean and the Mediterranean Sea (Stenella coeruleoalba, Delphinus delphis and Tursiops truncatus). They analyzed whistles from 49 hours of audio recordings made at the same time as the sightings and tested whether they could definitively identify dolphin populations by analyzing the acoustical parameters of the whistles.

This allowed them to correctly assign more that 82 percent of data to the correct dolphin population, based solely on the acoustic structure, a proof of principle that the acoustic structure of whistles can be used to monitor recent or rapid changes in the local population biology.

“More work is still needed to develop an automatic system for population recognition,” Papale said. She added that other research groups are focusing on the development of software but for the moment only for species-specific identification, not intra-specific recognition.

 

Source: www.sciencedaily.com

Marine Life & Conservation

The Big Shark Pledge: Shark Trust’s new campaign kicks off with a call for support

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With the ink still drying on last week’s landmark listing of nearly 100 species of sharks on Appendix II of CITES, the Shark Trust insists that this is not the time for shark conservation to take a break. The UK-based NGO this week launches its biggest-ever concerted campaign to tackle the overfishing of oceanic sharks. They are calling on people across the world to join the call for stricter controls on high seas fisheries.

The Big Shark Pledge is at the heart of an ambitious set of campaign actions. Working to secure science-based catch limits on all sharks and rays affected by the international high seas fishing fleet. The pledge will build the largest campaigning community in shark and ray conservation history to support a raft of policy actions over the vital years ahead.

Many of our best known and much-loved sharks make their home on the high seas. In our shared ocean, these oceanic sharks and rays face a very real threat from a huge international fleet of industrial-scale fishing vessels. Research published in early 2021 confirmed that over three-quarters of oceanic sharks and rays are now at risk of extinction due to the destructive impact of overfishing. They have declined by 71% over the last 50 years.

The Shark Trust is celebrating its 25th Anniversary this year and has a long history of securing positive changes for sharks, skates and rays. The Big Shark Pledge will build on the success of their NoLimits? campaign which underpinned landmark catch limits on Blue Sharks and Shortfin Mako in the North Atlantic.

While the listing of so many species on the CITES trade agreement is certainly a positive step, there remains a huge challenge in ensuring that sustainable practices are embedded in international fisheries.” says Shark Trust Director of conservation, Ali Hood. “Sharks on the high seas face extraordinary pressure from excessive fishing practices. This has to be addressed through international agreements such as those secured for Blues and makos.”

There is hope and a feeling of momentum in the shark conservation community. Just last week, in addition to the new CITES listings, the Shark Trust, working with partners in the Shark League, secured the first-ever international quota for South Atlantic Mako at ICCAT meeting in Portugal. The new campaign from the Shark Trust aims to push forwards from here, engaging a wave of support through the Big Shark Pledge to bolster policy action.

This will be a long-term international and collaborative effort. Forging a pathway to rebuild populations of high-seas sharks and rays. By putting science at the heart of shark conservation and fisheries management. And making the vital changes needed to set populations on the road to recovery.

Shark Trust CEO Paul Cox says of the Big Shark Pledge “It’s designed to give everyone who cares about the future of sharks the chance to add their voice to effective and proven conservation action. By adding their name to the Pledge, supporters will be given opportunities to apply pressure at key moments to influence change.

Click here to sign the Big Shark Pledge

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Gear News

Fourth Element X Sea Shepherd

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This year on Black Friday, fourth element announced their new partnership with Sea Shepherd, encouraging people to move away from mindless purchasing and to opt-in to supporting something powerful.

For 40 years Sea Shepherd, a leading non-profit organisation, has been patrolling the high seas with the sole mission to protect and conserve the world’s oceans and marine wildlife. They work to defend all marine wildlife, from whales and dolphins, to sharks and rays, to fish and krill, without exception.

Inspired by Sea Shepherd’s mission, fourth element have created a collection of fourth element X Sea Shepherd limited edition products for ocean lovers and protectors, with 15% of every sale going to the Sea Shepherd fund to help continue to drive conservation efforts globally.

“Working with Sea Shepherd gives fourth element the opportunity to join forces with one of the largest active conservation organisations in the world to try to catalyse change in people’s attitudes and behaviour. Fourth Element’s products are designed, developed and packaged with the intention of minimising our impact on the ocean environment, and with this partnership, we will be supporting the work of Sea Shepherd, in particular in their work on dealing with the twin threats of Ghost fishing nets and plastic pollution.”

Jim Standing fourth element co-founder

Read fourth element’s Sea Shepherd Opinion Piece HERE

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