The shark of the shallows: 1.6 m (5 ft) of slim gray body with a jet-black tip on the first dorsal fin, outlined in white and often visible above the surface as the animal works a lagoon in half a meter of water. Every fin is black-tipped, and the first dorsal marking is the clearest of any reef shark here.
It barely goes anywhere. Tracking studies find individuals holding home ranges of less than a square kilometer and returning to the same stretch of reef for years, sometimes for their whole adult life. A blacktip reef shark seen on a house reef is very likely the same animal seen there last season, and that fidelity is why local populations do not recover when a lagoon is fished out: nothing swims in to replace them.
Juveniles use the shallowest water available, sometimes in a few centimeters over a sand flat, where nothing large enough to eat them can follow. The adults hunt small fish, octopus and crabs across the reef flat at the top of the tide.
It is timid to the point of being difficult to photograph, and it accounts for almost no incidents beyond bites on the legs of people wading through schooling bait. The species is Vulnerable, and it is the shark most non-divers here will actually see.
The species.Carcharhinus melanopterus (Quoy & Gaimard 1824) - black-finned. ETYFish
How to recognise it
jet-black tip on the first dorsal fin, outlined in white
slim gray body, all fins black-tipped
often in water shallow enough to expose the dorsal fin
length to about 1.6 m
Why it's threatened
Residential & commercial development
Housing & urban areas · Commercial & industrial areas · Tourism & recreation areas
The Blacktip Reef Shark is caught throughout its range in industrial and small scale longline, gillnet, trawl and handline fisheries that occur in continental shelf waters and those around oceanic islands and reefs, especially those around coral reefs. Most are taken as incidental catch in general reef fisheries targeting teleost fishes. For example, in the waters of the Great Barrier Reef it makes up 1.1% of shark catch in inshore gillnets (Harry et al. 2011) and 5% of sharks caught in the line fishery for reef teleosts (Heupel et al. 2009). In Indonesia it makes up 0.3% of the elasmobranch catch landed at the port of Muncar (Winter et al. In press). While in Fiji, Blacktip Reef Shark makes up more than half of the sharks landed in small scale artisanal coastal fisheries (Glaus et al. 2015). The species is also taken in small amounts by recreational fishers in some countries. There is limited species-specific catch trend data available for most countries, however, throughout much of the species' range there are intensive coastal fisheries that are likely to exert significant pressure on the stocks. In many parts of east Africa, and south and east Asian, there are large amounts of fishing effort targeted at carcharhinid sharks in continental shelf waters, and the effort continues to increase. For example, in the waters of Indonesia effort by small-scale fisheries has tripled when taking population into account (Ramenzoni 2017); and in Myanmar the International Labour Organisation (2015) estimated the number of vessels participating in the small scale inshore fishery to be about 26,000 in 2013, and the number of locally operated larger offshore vessels numbered 2,846 in 2013, having increased nearly 30% since 2009. Only in locations where fisheries are strictly regulated (e.g. Australia) (Espinoza et al. 2014), where human population densities are low (Nadon et al. 2012), or where dive-based tourism supports protection (Sutcliffe and Barnes 2018) are there low levels of threat that enable this species to remain common.
This species is a common display species in public and private aquaria. It is exported live from countries such as Australia and Indonesia to aquaria worldwide.
The reliance of this species on coral reefs makes it susceptible to declines in habitat quality. Global climate change has already resulted in large-scale coral bleaching events with increasing frequency causing worldwide reef degradation since 1997. Almost all warm-water coral reefs are projected to suffer significant losses of area and local extinctions, even if global warming is limited to 1.5 ºC (IPCC Report, 2019). Destructive fishing practices in some nations (e.g. dynamite fishing) (McManus 1997) and declining water quality (MacNeil et al. 2019) have also led to the decline in coral reef habitat.
Threat classification from the IUCN Red List.
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