Galapagos shark  (Carcharhinus galapagensis)

Classified as Near Threatened (NT) on the IUCN Red List (1).

Named after the famous islands where it was first identified (3), the Galapagos shark is a large, rather slender species, with a brownish-grey back and sides, and a white underside (4). The first dorsal fin is tall, narrow and almost straight, and a low ridge leads to the small, second dorsal fin (4) (5). The trailing edges of the fins may be darker than the rest of the body, and the tips may be dusky (2). The Galapagos shark belongs to the Carcharhinus group of sharks, a name derived from the Greek words for ‘sharpen’ and ‘nose’ (5); however, the nose, or snout, or this species is broadly rounded (4) (5).

Despite its name, the Galapagos shark is found not only around the Galapagos Islands, but occurs in warm tropical waters around the world (2). Within this large distribution, the Galapagos shark appears to favour waters surrounding oceanic islands, such as the biologically unique Galapagos and the uninhabited Cocos Island off Costa Rica (4) (6).

Clear waters around rocky bottoms and coral reefs are the preferred habitat of the Galapagos shark (2). It can be found from surface waters down to a depth of 280 metres (1).

Moving though the oceans in loose groups or solitary (2), the Galapagos shark feeds on fishes, squid and octopus dwelling on or near the ocean floor (5). Occasionally, a large Galapagos shark may prey on other sharks (5), and around its namesake islands it has been observed taking sea lions and marine iguanas (2). It is an inquisitive fish and is known to approach swimmers and investigate other disturbances in the water, such as boats and divers (2). It can be an aggressive animal and, like some other shark species, performs a display prior to attacking its target. This involves arching the back, raising the head, and lowering the pectoral fins as it swims with a noticeable twisting motion (2).

The Galapagos shark gives birth to live young (5), with between 6 and 16 pups born in each litter (6). The shark pups, which measure around 70 to 80 centimetres at birth (6), initially remain in shallow areas where they are a little more protected from predators, which can even include other Galapagos sharks (5). The young will move into deeper waters as they grow (5), reaching maturity at lengths between 1.7 and 2.3 metres (2). This shark first reproduces at around ten years of age, and is known to live to approximately 24 years old (5).

Fishing activities are said to pose the greatest threat to this species (1), although it is not clear whether the Galapagos shark is being targeted by fishing operations, or is being impacted as bycatch.

The Galapagos shark is known from marine reserves, such as around the Kermadec Islands in the South Pacific Ocean, and the Galapagos Islands (1). Unfortunately, the benefits of the latter (and most likely other reserves as well) are undermined by illegal fishing (1).

View information on this species at the UNEP World Conservation Monitoring Centre.

To learn more about the threats to sharks and how you can help visit:

• Conservation International:
  http://www.conservation.org/learn/biodiversity/species/profiles/sharks/Pages/threats.aspx
• Shark Trust:
  www.sharktrust.org