Distressed damsel fish cry for help

Date:October 27, 2015

Source:ARC Centre of Excellence in Coral Reef Studies

Researchers at the ARC Centre of Excellence for Coral Reef Studies (Coral CoE) at James Cook University have found that fish release a chemical 'distress call' when caught by predators, dramatically boosting their chances of survival.

Fish harbour a chemical substance in their skin that's released upon injury. It triggers fearful and escape behaviour in nearby fish, but until now scientists hadn't identified the benefits to the sender.

"For decades scientists have debated the evolutionary origin of chemical alarm cues in fish," says study lead author, Dr. Oona Lönnstedt, now a research fellow at the University of Uppsala.

The researchers have now found the answer, discovering that the chemical cue attracts additional predators to the capture site.

"Chemical alarm cues in fish seem to function in a similar way to the distress calls emitted by many birds and mammals following capture," says study co-author Professor Mark McCormick from the Coral CoE.

Continued ...

Australia dolphins 'saved' by juvenile's distress call

The distress call of a young dolphin has been used to lure a large pod of the animals to safety, after it appeared they would strand themselves in shallow water.

Environment officials in Western Australia caught the juvenile and took it to deeper water, where its distress calls enticed the rest to follow.

One dolphin died in the incident.

A spotter plane reported that the rest - thought to number about 150 - had swum to the safety of the open sea.

The dolphins had been milling in shallow water at Whalers Cove near the town of Albany, on the south coast of the state.

"The juvenile was sending out distress signals, which was calling the dolphins in," conservationist Deon Utber told AFP news agency.

"As soon as it was translocated to deeper waters the pod followed it out and last we saw they were swimming out to sea."

http://www.bbc.co.uk/news/world-asia-21313216