Spotted Dolphin Age Classes

Underwater viewing …

Passengers left this morning and we will spend this afternoon and tomorrow morning readying the boat for the next group – cleaning the boat inside and out as well as prepping my research gear and reviewing data forms. So, I thought I'd take this message to share with you a bit about dolphin ages. Spotted dolphins are born without spots and as they age they acquire spots and continue to gain pigmentation throughout their lives. Spotted dolphins actually resemble little bottlenose dolphins when they are born (though spotted dolphins are a bit more 'refined' in appearance). When born, they have fetal folds which are vertical lines on their body from being folded up in the mother's uterus. These stretch out and are not visible when the calf is about one month old. Then, from age 1 month till about 3 years of age they are considered 'two-toned' or class 2 individuals. They still have no spots. When they reach about 3-4 years of age, spotted dolphins begin getting spots along their bellies and are called 'speckle-bellied' or class 3. Class 3 dolphins are juveniles. When their spots cover their entire bodies, but still seem spread out, individual dolphins are called 'mottled' or class 4. These dolphins are subadults and range in age from about 7 years to about 11 years in age. Adult spotted dolphins are also called 'fused' and are 12 years or older. With the possibility to identify different age classes, we can address many more questions about dolphin social life and behavior than from using only surface observations. But, since this message is getting long, I'll save some of that information for later this week. Cheers Kathleen