Whale sharks can be individually identified by their unique pattern of spots. Sally explained how an area on the left side behind the head is photographed, and a computer algorithm used to confirm an individual’s identity compared with a database of whale shark images. To date, over 700 individuals have been identified from photographs. This relatively cheap technique has advanced the study of the shark’s behaviour. Whale sharks can swim considerable distances; satellite tracking of tagged sharks have revealed journeys of over 5,000 km in Asia. Combined with biopsy data, we now know there are no isolated populations of whale shark – genetically they mix across the globe.
The whale shark can grow up to 20 metres long and live for over 50 years. They are filter feeders and capable of deep dives. The biodiverse seas around the Philippines are a vital habitat for the species and they are known to give birth there. They are now protected in the Philippines, though not in other the seas off neighbouring countries, with bans on catching whale shark been put into place relatively recently. They are now being exploited in a new way: tourism.
Sally emphasised that not all wildlife tourism is eco-tourism, in fact most is not. There are four areas where tourists are taken out in boats to see whale sharks in the Philippines. She contrasted whale shark tours in Oslob, where guidelines are not enforced, with an eco-tourism operation in Leyte that LAMAVE is helping operate. In Oslob, the whale sharks are crowded by too many boats and are approached too closely by divers; over 2,000 people can be in the vicinity of the sharks in a five-hour period. In Leyte, strict rules are enforced on how to approach whale sharks to minimise disturbance.
Commercial whale shark tourism operations are now provisioning – artificially feeding the whale sharks from boats to facilitate tourism. The LAMAVE team’s scientific data is showing that this can affect the sharks’ behaviour in an adverse way. They do not provision in Leyte and Physalus recommend that provisioning be stopped. Eco-tourism when carried out in a responsible manner, however, provides an alternative local source of income, can benefit conservation if environmental fees are charged, and can have a beneficial educational role.
Large Marine Vertebrate project Philippines
Shark Tales (Sally Snow’s blog)
Wildbook for reporting and identifying whale sharks