Despite their enormous size, basking sharks pose no threat to humans (they have tiny teeth and filter-feed on small copepod zooplankton), but the converse is true.  Basking sharks' surface-feeding behaviour, size and slow swimming speed make them extremely vulnerable to human impacts.

Like most shark species, their life history (low reproductive rate and late maturity - see the fact file page for further details) makes the population itself vulnerable if at all depleted by these impacts.

Fishing

Over the years basking sharks have been hunted for a variety of reasons. Flesh for food, cartilage for assumed medicinal properties, liver-oil for burning and lubricants, and fins for the Asian shark fin soup trade, have and in some cases still are, the impetus behind basking shark fisheries.  There were targeted fisheries in the UK, in the past, when it was hunted primarily for liver oil.  Due to the extreme vulnerability of the basking shark population, all such fisheries around the UK and Ireland collapsed.

Although now protected in some regions (see basking shark protection page), some nations/fishermen may still target the sharks. The sale of basking shark products is has been illegal within Europe since January 2007 (see picture, below, of a French supermarket in 2005), but some basking shark parts are so valuable that some fishermen may still be tempted to take basking sharks.

Bycatch

Another threat to sharks is bycatch in static fishing gear. This shark (below) was found just in time by divers off Achill Island, West of Ireland.  Its snout had become entangled in lobster pot ropes, during feeding with its mouth agape.  In this instance, divers managed to release the shark from the ropes and set it free, but bycatch in gill nets is believed to be a serious problem.

Disturbance and Harassment

Raising public awareness of this wonderful creature is not without its drawbacks, as the species is now suffering from its new status as a tourist attraction.  Naive but deliberate disturbance from a curious public is an increasing threat.  We have received numerous reports of the kind of incident shown in the picture below: a young basking shark has been surrounded by speedboats.

It is illegal to intentionally disturb a basking shark in this way (under Schedule 5 of the Wildlife and Countryside Act).  Please report such incidents to us, at MCS, and also to the local police force's Wildlife Liason Officer.

Collisions with boats are not unusual, as a feeding shark will not necessarily take evasive action.  The image below shows the damage that propellers can cause to basking sharks.  But even without collisions, human disturbance is harmful and illegal.  Please follow the basking shark Code of Conduct.