UPDATE ON THE SHARK RESEARCH AND CONSERVATION PROGRAMME IN GALAPAGOS

Background

The Galapagos Marine Reserve (GMR) fully protects sharks within its boundaries and given its great size, this region probably represents the largest shark refuge worldwide. However, since the 1980s there is strong evidence of the continued occurrence of illegal shark fishing within the Galapagos Marine Reserve by fishermen outside of Galapagos. Sharks are primarily exploited for their fins, which are highly valued in Asian markets. The sharks are caught in nets, have their fins cut off and then thrown back into the water to die.

This is reflected by an increase in shark fins confiscated by the Galapagos National Park Service, whose capture of fins has risen from 556 fins in 1996 to over 13000 fins during the last five years. Species identified by fins confiscated were 90% requiem sharks (silky, black tip, Galapagos, sandbar, blue sharks, etc.), 10% hammerheads, 0.4% thresher sharks and 0.1% whale shark.

Importantly, observations of catch composition and fins confiscated from industrial and artisanal vessels fishing illegally in the northern region of the Archipelago have revealed the presence of a significant proportion of juvenile hammerhead and requiem sharks. Because their schooling habit and a combination of biological characteristics such as slow growth, long lifespan, late maturation, annual reproductive cycle and long gestation period, hammerhead and requiem sharks are considered vulnerable to overexploitation. Therefore, an immediate need exists to investigate the sex and size distribution, abundance, site fidelity and home range of shark species in the region, in order to assess whether or not the Galapagos Marine Reserve adequately protects areas such as nursery or birthing habitats and resident sharks populations.

Currently, scientific knowledge of sharks and the biological basis for their management in the Galapagos Islands is very poor. Local scientists, authorities and tourism operators see sharks species as a priority to study and conserve.

This programme aims to systematically gather information in field studies on population structure, spatial distribution, home range and biological status of some species of shark in the vicinity of Darwin and Wolf islands, the locations of highest shark densities.

We need your help to achieve this. We need to raise £16,000 to reach our target and fund this work. Please give a donation and help save a shark by visiting Online donation, or contact the GCT office on 020 7629 5049.

Objectives

The overall mission of the Shark Research Programme is to provide stakeholders and authorities with the necessary technical information for the conservation of shark species in the GMR. The programme focuses on three species of shark: the scalloped hammerhead (Sphyrna lewini), the Galapagos shark (Carcharhinus galapagensis) and the whale shark (Rhincodon typus).

General Objectives

• To understand the importance of the GMR and specific sites within the GMR to sharks
• To understand the regional migration patterns of the coastal-pelagic sharks
• To raise awareness locally of the importance of sharks in the marine ecosystem
• To provide local and national authorities with technical information on which to base conservation management decisions regarding sharks

Update

A trip was carried out to Darwin and Wolf to download the information from the receivers deployed at the two study sites: The Derrumbe (SE Wolf) and the Arch (SE Darwin). The sites are separated by approximately 25 miles of open water. Following is a summary of the preliminary results:

1. All four receivers were located and information was successfully downloaded.
2. Data were recorded for 16 hammerheads (out of 18 individuals tagged), and for all three Galapagos sharks and the whale shark.
3. The whale shark left the site soon after being tagged but was registered again briefly on 4 September (after an absence of aprox 6 weeks).
4. Two of the Galapagos sharks moved from Darwin Arch to Wolf Derrumbe.
5. 10 hammerheads moved from one site to the other. One of these individuals, a small (1.5 m length) female, moved back and forth at least three times.
6. Some of the sharks were still present at the sites during this trip, three months after tagging.
7. At least two unidentified tags were registered. We are currently in conversations with VEMCO (the manufacturers) to help us identify who used these tags and what species they are working with.
8. During the trip, we had 7 encounters with whale sharks, some of which were photographed. The photos are currently being processed in order to send to www.whaleshark.org which provide identification services (based on the spot patterns of individuals).

Source: Charles Darwin Research Station

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