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Pelayo Salinas

Shark Ecology and conservation

Active since 2007

Sharks have thrived on our planet for over 400 million years. Yet overfishing has drastically reduced global shark populations, with many species now threatened with extinction. Our scientific work seeks to inform conservation measures, so sharks are better protected in Galapagos and the Eastern Tropical Pacific.

Jordi Chias

The challenge

It is estimated that more than a third of all shark and ray species are threatened with extinction. Overfishing is the main cause behind these dramatic population declines, with an estimated 100 million sharks fished every year around the world. Around 75% of oceanic shark species are at risk of extinction today.

Since 1998, sharks have been protected from industrial fishing in Ecuador by the Galapagos Marine Reserve (GMR), and more recently in 2022 by the Hermandad Marine Reserve. However, many shark species are migratory and swim thousands of kilometers, often across unprotected waters, to mate, feed, and nurse. In these waters, they are vulnerable to fishing, which is often illegal, unregulated, and unreported. It is therefore critical that we understand how to better protect these iconic species beyond the marine reserves, and across their migratory region.

Understanding how to improve shark conservation is crucial to give these animals a future in a rapidly changing planet. Join us on a journey of scientific discovery and exploration to save sharks and preserve marine life diversity!

What we do

The islands of Darwin and Wolf, to the north of the archipelago, aggregates one of the largest shark biomasses on Earth, providing a unique opportunity for researchers to study sharks. Here our shark researchers work to conserve many of the species found inside the Galapagos and Hermandad Marine Reserves. They do so by monitoring the number of sharks over time, evaluating the status of their populations, and studying their movement patterns and the levels of connectivity among populations at a regional level.

Our research focuses on vulnerable, endangered, and critically endangered species, such as scalloped hammerhead sharks, Galapagos sharks, tiger sharks, blacktip sharks, silky sharks, blue sharks, among others.

Jordi Chias
Adult silky shark.
Keith Ellenbongen
Principal Investigator Pelayo Salinas conducting shark research in Cocos Islands Marine Park.

Why it matters

Sharks are essential to the health and balance of marine ecosystems. They help to maintain the health of reefs, seamounts, mangroves, shores, and promote the stability of these fragile ecosystems. Many species also play a vital role as apex predators, helping to control populations of other species and maintain biodiversity.

By gaining a better understanding of the movement patterns, habitat use, and population dynamics of sharks in Galapagos and the surrounding waters, we are providing information for more effective conservation measures that protect shark populations in Galapagos, the Eastern Tropical Pacific (ETP), and beyond. Furthermore, the data generated over the years by the project are essential to help in our understanding of the growing effects of climate change on shark populations.

In Galapagos, sharks are also of great importance to the local economy, given that the marine tourism industry, which heavily relies on shark sightings, provides employment to 37% of the active local workforce. Some estimates determine that on average a live shark in Galapagos is worth $360,000 per year, while one fished for its fins in another part of the world generates no more than $200.

Specific program objectives

  • Evaluate the effectiveness of the GMR in protecting sharks and predatory fish, and assess the impact of El Niño cycles on their populations.
  • Monitor the abundance of coastal and oceanic shark populations in the GMR and surrounding waters. Investigate variations in the composition of shark communities inhabiting the ETP region.
  • Conduct long-term monitoring of tiger shark movements to understand their use of the GMR.
  • Identify and characterize the migratory and connectivity patterns of oceanic, tiger, and hammerhead sharks within the GMR and across the wider ETP region.
  • Assess the socio-economic value of sharks as a tourism resource in the GMR.
  • Provide information about the status of shark populations to the Galapagos National Park Directorate to contribute to the development of conservation strategies to protect the diversity and health of shark communities.
  • Provide information about the status of shark populations to government authorities in order to contribute to the development of improved management plans within Ecuadorian waters and the ETP.
  • Raise awareness about the importance of sharks in marine ecosystems through educational campaigns directed at the local community, particularly children and youth.

Our impact

Satellite tracking of pregnant females of the critically endangered scalloped hammerhead shark has shown that they migrate from the Galapagos Islands to coastal areas of Central and South America to give birth, exposing them to heightened risks of fishing on their journeys. This finding highlights the importance of regional fisheries management of shark populations.

Stable isotope studies conducted by our researchers suggest that hammerhead sharks in the GMR respond to climate fluctuations, potentially benefiting from an improved diet during La Niña events, as the overall marine productivity in the region increases during these events. This finding highlights the vulnerability of shark populations to climate change.

Blue sharks are truly oceanic wanderers, they are also one of the most heavily-fished shark species globally, and among the top three most captured sharks in Ecuadorian waters. In 2023, we started a blue shark tagging program to learn more about their movement patterns in the region. This information will be key to identifying areas of overlap with the numerous artisanal and industrial fishing fleets that operate in the ETP region, and inform management actions aimed at reversing ongoing population declines.

Silky sharks are also one of the most heavily-fished shark species in the world. Our researchers have analyzed data from more than 70 silky sharks tagged with satellite transmitters since 2021. Many sharks were tracked for more than a year, and some for up to two years. In fact, many of these sharks are still being tracked. This research has yielded the longest track of a silky shark to date, with one female shark traveling over 33,000 km in 1.5 years half-way to Hawaii and back again, twice. Indeed, many of the tagged sharks spent large periods of time outside of marine protected areas, and at least three have been caught and killed by fishing vessels. These findings highlight the need for ambitious and comprehensive regional management strategies to improve fisheries management and reduce ongoing silky shark population declines across the ETP region.

Our satellite tagging research has revealed that tiger sharks stay inside the GMR for long periods of time, with some individuals spending over 90% of their time within the reserve. This suggests that the GMR provides essential habitat for tiger sharks. Studies have also revealed the ecological importance of green sea turtles in the diet of tiger sharks in the GMR.

Why you should support us

Fishing and climate change are putting unprecedented pressures on shark populations in the ETP region, and impacting the populations in Galapagos. As a result, long-term conservation of shark communities will only be possible if science-based management and mitigation strategies are developed and implemented effectively. By supporting our program, you are helping to protect sharks and ensure the long-term health of marine ecosystems.

Here are some specific reasons why you should support our program:

  • To help protect sharks, which are major players to the health and balance of marine ecosystems.
  • To support the development and implementation of science-based shark conservation strategies.
  • To support the development of expanded marine protected areas in the region.
  • To help ensure that shark populations in Galapagos and the region are conserved, and can be appreciated by future generations.
Bibliography

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Cerutti-Pereyra, F., Moity, N., Dureuil, M., Ramírez-González, J., Reyes, H., Budd, K., Jarrín, J.M. and Salinas-de-León, P., 2020. Artisanal longline fishing the Galapagos Islands–effects on vulnerable megafauna in a UNESCO World Heritage site. Ocean & Coastal Management, 183, p.104995. https://doi.org/10.1016/j.ocecoaman.2019.104995

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Habla Tiburón: conserving sharks and rays in Ecuador

Ecuador has been a leader in ocean conservation in recent years. Right now, 13% of Ecuador's exclusive economic zone has some level of management, and the government has promised to protect 30% of it by 2030. However, illegal, unreported and unregulated fishing (IUU) is still a big problem for shark conservation today.

Since June 2023, our shark researchers and fisheries conservation team have been working with WWF Ecuador on an ambitious project to improve how we manage our seascapes and ensure that shark and ray populations in Ecuadorian waters are managed sustainably.

The project aims to:

  • Strengthen fisheries governance through a participatory model;
  • Strengthen monitoring, control, compliance and traceability capacities of national authorities and fisher associations to combat IUU fishing;
  • Promote responsible fishing practices by implementing market and conservation incentives; and
  • Drive the conservation of sharks and rays in Ecuadorian waters.

This 5-year project, called Habla Tiburon, is being implemented with the support of the United States Agency for International Development (USAID).

Octavio Aburto

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