Long-term impacts of fish provisioning on the behavior and survival of wild bottlenose dolphins

Published source details Foroughirad V. & Mann J. (2013) Long-term impacts of fish provisioning on the behavior and survival of wild bottlenose dolphins. Biological Conservation, 160, 242-249.
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This study is summarised as evidence for the following.

	Action	Category
	Limit, cease or prohibit feeding of marine and freshwater mammals by tourists Action Link

Limit, cease or prohibit feeding of marine and freshwater mammals by tourists

A controlled, before-and-after study in 1988–2011 at a marine reserve in Shark Bay, Western Australia (Foroughirad & Mann 2013) found that after setting limits on feeding of bottlenose dolphins Tursiops spp. by tourists, the survival of calves born to females being fed increased and was similar to calves of non-fed females, but calf behaviour differed to those of non-fed females. The survival rate of calves born to females being fed was higher after feeding limits were set (87%) than before (23%) and did not differ significantly to calves of non-fed females (62%). However, calves of females fed limited amounts spent less time in close contact with their mothers (average 33% of their time) and more time foraging (22%) than calves of non-fed females (with mother: 39%; foraging: 16%). In 1988–2011, dolphins were hand-fed fish by tourists in knee-deep water along 90 m of beach. In 1988–1993, dolphins were fed up to 120 kg of fish/month. In 1994–2011, feeding was limited to 2 kg of fish/day during a maximum of three sessions between 07:30 h and 13:00 h. Dolphins (seven fed females with 19–22 calves, 53 non-fed females with 82 calves) were observed during feeding sessions (total 308 h) and offshore (total 2,181 h) in 1988–2011 before and after feeding was limited (number of observations before and after not reported).

(Summarised by: Anna Berthinussen)