Science for everyone

How isolated are the dolphins of Bocas Del Toro?

September 15, 2014

How isolated are the dolphins of Bocas Del Toro?

The first time Dalia Barragán pulls the trigger, you might think there’s something wrong with her rifle. Instead of a powerful bang, there comes a hollow pop

The first time Dalia Barragán pulls the trigger, you might think there’s something wrong with her rifle. Instead of a powerful bang, there comes a hollow pop. A bright orange tube jumps from the barrel on a quickly decelerating arc. With a lot of skill on Dalia’s part – and a little bit of luck – its point safely grabs a tiny skin sample from the rear of a bottlenose dolphin.

Barragán’s studies the genetic history of the Tursiops truncatus in Bocas Del Toro, Panama. When she began in 2012, Barragán expected the tissue samples would show that the dolphins’ gene pool was occasionally spiced up by mates from outside the archipelago. It turns out the 150-some dolphins in the local population are extremely isolated.

This has one major implication. If the 150 dolphins of Bocas decline or disappear due to increased human pressure from tourism and other increasing human pressures, the chances of it rebounding are slim to nil.

Barragán’s work suggests a single breeding pair of bottlenose dolphins arrived in the archipelago’s shallow waters within the last few thousand years. Mitochondrial DNA trace all 40 of her sampled individuals to a single female. The population’s genetic complexity is simpler when compared to T. truncatus in other parts of the Caribbean.

“In terms of conservation, this (result) is very important, especially because people here live off of dolphin tourism,” said Barragán, a master’s student at Colombia’s Universidad de los Andes. Her research based at STRI’s Bocas Del Toro Research Station has led to two recommendations to the International Whaling Commission and laid groundwork for genetic population studies further afield.

Back

PrintPrint article   ArchiveMore articles   Send your commentsComments