Our final Risso's dolphin blog takes us on our first (and last) journey to the southern hemisphere to meet researcher Oli Yates who is as far as literature suggests, conducting the only dedicated southern hemisphere research on this species. Being able to understand more about Risso's dolphins in different areas of their distribution is crucial (and fascinating) to the future conservation of the species and WDCS is proud to support Oli in his endeavours ... and after reading his blog, I'm off to book my ticket to Chile!
Enjoy ... and come back in October for some harbour porpoise madness!!
At eight thirty on Sunday morning the phone rang. Who could possibly be calling at this time on a Sunday I wondered aloud? It might be family, calling from England and getting the time difference wrong… In Chile we are four hours behind GMT but with daylight saving hours we end up with three to five hours difference – who can keep track?
I answer the phone and it’s not family but Señora Ana María, who lives on the eighth floor of the department block that looks over the bay. “Hello, good morning!” she says happily, “the dolphins are in the bay again, lots of them today and they seem very active!”
Since we began this project we have depended on volunteers from the local village to help us monitor the presence of Risso’s dolphin in La Herradura Bay (Horse Shoe Bay). Several people whose houses look out over the bay let us know when they see the dolphins, which greatly supports our opportunistic data collection.
The bay is about two kilometres across and is enclosed on all sides but for a narrow entrance that opens out into the Pacific Ocean. The calm waters of the bay allow us to use kayaks to approach the dolphins and take photos for the study without impacting the population with noise from an outboard motor.
Once the dolphins arrive I know I have about an hour to get the kayak in the water and paddle out to them. The group today included around 65 individuals, which is about average for the population we are studying in Chile. On some days two or three different groups come together and all of a sudden you can find yourself in the middle of 300 or so dolphins!
Whilst in the kayak the dolphin behaviour is typically inquisitive, they frequently pass under the kayak looking up through the clear water at what must look like a giant banana floating at the surface (the kayak is yellow!). By staying close to the centre of the bay, I can generally wait while they pass by repeatedly as they relax and socialise in the relatively shallow water.
This way we sample (take photos of) as much of the group as possible while they pass by without having to exert too much energy following them. This is greatly facilitated when the group is calm as they move much more slowly, so it is in our best interest to avoid any disturbance.
Today they only stayed for 45 minutes while they breached and slapped the water with their flukes. The Risso’s tend to breach often, almost always turning in the air to impact with the water on their side. They continued to display like this as they left the bay heading north and left me to go and find my breakfast.