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Creature Feature: Broadnose Sevengill Shark

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In this series, the Shark Trust will be sharing amazing facts about different species of sharks and what you can do to help protect them.

Written by guest contributor – Yolanda Evans.

A small glimpse of grey amongst the the vibrant green of the kelp around the temperate coastal waters could be no other then the incredible Broadnose Sevengill shark! Hinted by their common name, these sharks have seven pairs of gill slits – unlike the typical five. These sharks can reach up to 3 metres long and are commonly misidentified as the other species of sevengill the Sharpnose Sevengill. The Broadnose is distinguished by small black and white freckles on their fins and underside and a much larger head then the Sharpnose.

Unlike many other sharks in the Hexanidae family (Cowsharks), this species prefers waters of less then 50 m in depth; sometimes being found in river estuaries where the depth is around 1m! However, Brodnose’s make seasonal migration during the winter to the continental shelves, following their food and sexually mature females.

Broadnose Sevengill’s have a unique tooth shape in their lower jaws: they are shaped like combs which they use to anchor into their prey. This sharks favourite snacks large fish (including other sharks) and crustaceans but they have been videoed eating carrion (dead/decaying bodies), making them scavengers. There are even reports of cannibalism as the older sharks eat the younger to reduce competition. Once they’ve eaten a meal they wont have to eat again for weeks, in fact, in a month they only consume 6% of their body weight!

Predominantly being a solitary shark, they do sometimes congregate in groups to hunt. They mainly do this to get to bigger prey which could be too much work for a single shark. Stalking behind their prey, these sevengill’s will then rapidly burst out to chase down their prey.

Sevengill’ are ovoviviparous and can give birth to 60-180 pups, an incredibly high amount. The pups remain in the shallow waters until they reach a certain size to help avoid predators.

Recent carcasses of these sevengill’s have been found worldwide, all with their livers missing. Who could be behind this series of surgically-precise murders other then the infamous Orca. Orca, or Killer Whales,purposefully seek out Broadnose Sevengill sharks for their livers rich in fats, making a high calorie snack for these mammals. The Orca turn the shark over on their backs, putting them in a state of tonic immobility, and then using their sharp conical teeth they precisely remove the liver leaving the rest of the shark as it doesn’t have the same nutritional value. However, a few videos have emerged of these Orcas then playing with their food, pushing the dead sharks body up and down with their snouts!

Orca’s aren’t the only mammal to purposefully hunt down these sharks as the Broadnose Sevengill’s are also targeted by humans for their meat, skin for leather, and their oil, however, their main threat is being caught as by-catch during industrial fishing. The IUCN lists them as Data Deficient, however, it is expected that they are Near Threatened.

SCIENTIFIC NAME: Notorynchus cepedianus

FAMILY: Hexanchidae

MAXIMUM SIZE: Up to 3.3 meters (10.8 feet) in length

DIET: Feeds on a variety of prey including fish, squid, crustaceans, and even other sharks

DISTRIBUTION: Broadnose Sevengill Sharks have a cosmopolitan distribution, found in coastal and offshore waters in temperate and tropical regions worldwide.

HABITAT: Found in a variety of habitats, including estuaries, bays, and shallow reefs, as well as deeper waters of up to 150 meters (492 feet) in depth.

CONSERVATION STATUS:

While there is little data on population trends, this species is known to be caught as bycatch in some commercial and recreational fisheries, and there is also concern over the impact of habitat loss and degradation on their populations.

For more great shark information and conservation visit the Shark Trust Website


Banner image – Aaron Scheiner | Wikimedia Commons

In-text Image – derekkeats | Wikimedia Commons

In-text Image – Coco | Wikimedia Commons

The Shark Trust is the leading UK-based shark conservation charity. The team works globally to safeguard the future of sharks, and their close cousins, the skates and rays. Engaging with a global network of scientists, policymakers, conservation professionals, businesses and supporters, to further shark conservation. Established in 1997 to provide a voice for UK sharks, the Shark Trust has an ever-growing number of passionate supporters. And together we're creating positive change for sharks around the world. Want to join us and help protect sharks around the world? Click here! www.sharktrust.org

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Saba’s Plan for a Coral Comeback

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Saba

Saba has an exciting new initiative to restore its coral reefs. This new project, running from 2024 to 2026, will focus on reviving key species in the island’s underwater ecosystems. With a collaborative team from the Saba Conservation Foundation (SCF) and Van Hall Larenstein (VHL) University of Applied Sciences, the project aims to restore both corals as well as sea urchins.

This initiative is centered around coral restoration, specifically reviving two essential coral species—staghorn coral (Acropora cervicornis) and elkhorn coral (Acropora palmata).  By mapping parent colonies and using a technique known as coral gardening, SCF will create and maintain coral nurseries. These corals will eventually be outplanted at key reef sites around Saba to not only expand the number of coral colonies, but also provide essential fish habitat. The project focusses on installing coral nurseries, training staff with the newest techniques and starting with the restoration of key reef sites.

Saba

Reef Cleaners to the Rescue

It’s not just corals getting a makeover—this project also shines a spotlight on the essential role of grazers, particularly sea urchins. VHL is leading the charge on cultivating and restocking two key sea urchin species, West Indian sea egg (Tripneustes) and long-spined sea urchin (Diadema), known for their ability to keep algae in check. By removing algae, which are important competitors of corals, they help the coral to thrive. By restoring these “reef cleaners,” Saba’s project will give corals the breathing room they need to grow, setting the stage for a healthier, more balanced marine ecosystem.

From Tiny Urchins to Big Goals

The project will be funded as part of the Dutch Government’s Nature and Environment Policy Plan (NEPP) 2020-2030 for the Caribbean Netherlands, a comprehensive initiative aimed at conserving and restoring the unique natural environments of the Dutch Caribbean islands, including Saba, St. Eustatius, and Bonaire. This project is aiming for big milestones:  build and maintaining coral nurseries, the expansion of urchin cultivation facilities, and the creation of a dedicated research center. By 2026, the project hopes to ramp up coral and grazer restoration, with the ultimate goal of extending these efforts across the Dutch Caribbean. By linking local initiatives to broader regional goals, Saba’s restoration project promises to leave a lasting impact on both the environment and the community.

Find out more about the DCNA at dcnanature.org.

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Reef-World marks two decades of marine conservation: strengthening impact amid coral reef threats

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reef world foundation

Empowering ocean stakeholders to tackle future challenges and ensure the survival of coral reefs and humanity

2024 marks the 20th Anniversary of The Reef-World Foundation’s tireless efforts for global coral reef conservation. The UK charity is the international coordinator of the UN Environment Programme’s Green Fins initiative, known as the leading voice in sustainable marine tourism. Today, Reef-World released its 2023-2024 Impact Report outlining a year of substantive growth and impact in its marine conservation programmes. 

Impact Report Highlights:

  • Impressive improvements in environmental behaviours to protect coral reefs by the marine tourism industry as the global participation of Green Fins increases.
  • Continued capacity building for government and NGO staff to effectively manage marine tourism activities in Asia, Caribbean and Red Sea regions. 
  • For the first time in Green Fins’ 20-year history, tourism operators have achieved ‘Best Environmental Performer’ status by demonstrating the lowest possible environmental impact in their environmental assessments. In 2024, three dive operators achieved this challenging milestone. 
  • Significant increases in global participation of Reef-World’s innovative digital conservation tools.
  • 138 Green Fins dive operator members achieved the strict threshold for PADI Eco Center recognition.
  • Developed four new educational materials and translated two into 16 languages to support the marine tourism industry in achieving sustainability targets.
  • Establishing a new Reef-World Development strategy and recruiting new roles – Development and Programmes Managers. 
  • Reef-World’s board welcomes new Chair and Trustees strengthening organisational leadership. 

Reef-World started as a one-person mission to inspire and empower communities to act in conserving and sustainably developing coral reefs and related ecosystems. Today, the team of 12 continues to meet this mission by inspiring and empowering the global marine tourism community to be exemplary sustainability leaders by using the Green Fins guidelines and tools to simultaneously use and protect the world’s precious reefs. 

In April 2024, the fourth global coral reef bleaching event was confirmed. Reef-World’s work has never been more urgent as the marine environment, and the benefits they provide humanity, continue to be eroded by global threats. The reduction of local threats, like those from the marine tourism industry, is an essential step to ensuring a future where coral reefs survive and continue to support the millions of people who depend on their ecosystem benefits. Reef-World’s work buys time for coral reefs and related ecosystems to be resilient to the impacts of global threats. 

 

“Right now our corals are facing the greatest fight of their existence as the terrifying predictions of the steps towards their complete extinction are starting to come true. But all is not lost, reefs are resilient and they have existed on this planet for millions of years. We must take action now, to buy time for reefs by reducing threats facing them and allowing them to react and adjust to the changing environment they need to survive in.” – Chloe Harvey, Executive Director

Looking Forwards: 

Like coral reefs, the Reef-World team needs to be resilient in the face of the complex challenges of the conservation sector. Reef-World has invested significantly in developing a Culture of Care to ensure the well-being of its team on a daily basis, continuing to be an exemplary employer to enable its team to best achieve the mission for coral reef conservation.

With the foundations of a Culture of Care and organisational development laid, Reef-World is emerging from the end of a natural organisation life cycle, that brings the challenges of growth and scale, stronger than ever. With a new strategy in place to generate much needed resources, Reef-World is excited for the opportunities to leap forward, continue to scale our impact and lean into new innovations and untapped opportunities for marine conservation. 

We continually strive to become a forward-thinking organisation that delivers on our goals and commitments to our stakeholders with fresh approaches and not being afraid of steering away from a “normal approach.” This approach is not only applied to our programmes of work but also internally and carries over to our Culture of Care for our team.” — JJ Harvey, Operations Director

reef world foundation

The Reef-World Foundation is immensely grateful for the continued support of its grant funders: UN Environment Programme, IUCN’s Blue Natural Capital Financing Facility, Adventure Travel Conservation Fund, PADI Aware Foundation, and World Nomads Footprints Program.

Reef-World would also like to express its gratitude to international partners whose vital support has resulted in significant tangible benefits for our work and mission: PADI; Professional SCUBA Schools International (PSS); Explorer Ventures; 1% for the Planet; ZuBlu; Snorkel Venture, GSTC; Dive O’Clock; Seven Dragons; DiveAssure and Eco Beach, without whom these achievements would not be possible.

The full 2023–2024 Annual Impact Report is available on Reef-World’s website.

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