April 6 - Franciscana vs. Bottlenose Dolphins

From left to right: Roberto, Lea, and Yaana has moved to the mouth of the bay, where she spent time shortly after she was originally tagged, about a month ago.

Over the past few weeks, Tango (a team member from San Blas who has his own boat) has seen several tagged dolphins while out on the bay, but he was unable to distinguish them by eye. Pablo plans to get a team with a digital camera into the field within the next two weeks to document the tags and identify distinctive individuals.

So, what do they look like? Check out the photo to the right... Franciscana dolphins are very different from bottlenose dolphins (the species that I see and study in Florida---and that you can see at Brookfield Zoo). Adult franciscanas are the size of bottlenose dolphin calves. They have a long rostrum, with hundreds of tiny sharp teeth (as compared to the bottlenose’s short beak with about 100 medium sized teeth). They have a chocolate brown body, matching the color of the estuarine water in which they live. Their eyes are small. Their flippers are relatively large, perhaps reflecting a need for greater maneuverability around features on the sea floor. Franciscana dolphins tend to surface slowly, sometimes with their long beak coming out of the water. I have never seen one jump out of the water.