From Wildlife Extra:
Basking shark births witnessed for the first time
Basking sharks have been breaching – Very unusual behaviour
June 2009. Snorkellers have witnessed basking shark behaviour never before seen anywhere in the world. Up to five basking shark pups have been born to two females during a mass gathering of the world’s second largest fish, off the coast of Cornwall.
900 Basking shark sightings
During the last month, the Cornwall Wildlife Trust, along with Seaquest, has run a surveying project funded by British International Helicopters. To date, the 40 trained volunteers have sighted a basking shark every day, with an estimated 900 sightings in total.
Basking shark breaching
Tom Hardy, marine conservation officer for Cornwall Wildlife Trust, has also reported six basking shark breaches during this period. Breaching is incredibly rare behaviour and was photographed in the UK for the first time in 2006.
According to Joan Edwards, head of marine policy for The Wildlife Trusts, this behaviour is usually only seen in large groups. She said: “This is a fantastic opportunity for science and to advance our understanding of this spectacular species. This just goes to show, what an important marine habitat the UK provides and enhances the importance of protecting such hotspots for this species.
“We just don’t know enough about their behaviour. There are theories about breaching being a form of communication linked to mating rituals or behaviour. It may be to do with males herding females. So we would issue a word of caution to people not to get too close to this supergroup. There is a risk of breach. And human contact may also have effects on the young or potentially the entire group.
Mating and reproduction
“This is fantastic timing. The Wildlife Trusts believe some areas of the South West coast and west of Scotland are seasonally very important areas for the mating and reproduction of basking sharks. The Marine and Coastal Access Bill, which will be discussed by MPs in Parliament next week, will hopefully provide us with the legislation that will allow us to establish Marine Conservation Zones for our marine wildlife, including basking sharks.”
Basking shark numbers
It is estimated the basking shark population in the north-east Atlantic has declined by more than 95% from historic levels. In the past, the major threat was hunting, and more than 80,000 basking sharks were killed in the north-east Atlantic. Now, with the fishery closed, the key threats arise from collisions with boats and entanglement in fishing gear.
Basking shark breeding
Basking sharks are slow-growing, late to reach sexual maturity at 12-20 years – and produce few young – bearing five or six pups for a gestation of one to three years. This makes them extremely vulnerable to over-exploitation. Even when threats are removed, numbers take a very long time to recover.
Basking shark survey
Between 1999 – 2007, The Wildlife Trusts’ basking shark survey counted, observed and photographed sharks off the UK’s western coasts. Volunteer crews were recruited from the membership of The Wildlife Trusts and Earthwatch Institute (Europe) to help with the surveys. All volunteers received full training in all aspects of appropriate survey technique, from observation procedures to data gathering and recording.
The survey revealed basking shark hotspots off the southwest of England, Northern Ireland and Scotland where they gather for feeding and courtship. The Manx Wildlife Trust has previously identified hotspots around the Isle of Man. For more information visit
Basking shark strands in Cornwall: here.