By Jessica Taylor/Correspondent
Although dolphins can be seen on the Outer Banks year-round, they are mainly sighted in the Roanoke Sound from May through October. The Outer Banks Center for Dolphin Research (OBXCDR) monitors the dolphins in the Roanoke Sound through a research technique known as photo identification. Aboard boat-based surveys, we photograph the distinctive markings on dolphins’ dorsal fins, catalog these photos and identify and track individuals over time. Over the years, we learn more about the individuals’ behavior and gain a glimpse into their lives. We become aware of the dolphin “gossip” in the sound, such as which are currently interacting with each other and which appear together consistently, best friend style.
We can distinguish males and females from watching their behaviors. Females raise their calves for approximately three to five years in the Roanoke Sound; if we see an adult dolphin at least three times with a calf, we can assume that dolphin is a female.
However, dolphins don’t maintain typical family units like people do. Males and females are monogamous for about 5 seconds, so we can’t assume that two seen together are male and female. In fact, two adult dolphins spending time together are more likely to be males.
Male dolphins typically form pairs as they enter adulthood, and these pairs may last for life. In pairs, they can help each other find food and evade predators. Most importantly, males get better access to females when they’re paired up. Studies across the country suggest that there’s typically one “stud” and one “dud” for every male pair, with one guy getting more girls than the other, but both males benefit from having a wingman.
When male pairs are spotted together, they’re seen coordinating their behaviors, swimming synchronously and pairing together with other males. For dolphin researchers, these pairs help us track the individuals’ stories.
Most famously, Onion and Pinchers were documented by OBXCDR, Nags Head Dolphin Watch and the NC Maritime Museum research group in Beaufort, NC, for nearly 20 years— always seen side by side. After Pinchers passed away in 2012 (he was found on the beach in Kill Devil Hills and reported to the OBX Mammal Marine Stranding Network), Onion formed a new pair with another older male, Moe, who had also recently lost his pair, Bud. Moe eventually passed in 2015 (the pier house at Jennette’s Pier has an exhibit of his skeleton where visitors can learn more about his life!). Onion then paired with another male named Shallot, and the two have since been spotted together regularly.
Not all pairs last as long as Onion and his friends. In 2008,we began to piece together the other male pairs of the Roanoke Sound: Bud and Moe, 708 and Sequoia, Rake and 92 and Sprite and Cola. The pairs were consistently seen at each other’s sides. Then, about five years ago, the things began to change.
Rake was seen without92, instead spending more time with Cola. Sprite stopped surfacing with Cola and began to surface with another male, Skylar. 708 and Sequoia split up, and Sequoia showed up with Jetson.
Maybe there were disagreements about feeding spots. Maybe fights over female dolphins led to these splits. Whatever the cause, their behaviors raised questions: Why don’t all males stay together? How do they pick their pairs? And how do they know when it’s time to switch?
As we continue to monitor the dolphins, we will learn more about their motivations for the friends they choose, the choices they make, and the importance of Roanoke Sound and the Outer Banks to their “summer memories.”
Biologist Jessica Taylor is Executive Director of the Outer Banks Center for Dolphin Research. She has a Bachelors of Science in marine sciences from Rutgers University and a Master’s in coastal environmental management from Duke University. She has participated in field research studies of bottlenose dolphins, humpback whales, Steller sea lions, and predatory fish in Florida, South Carolina, New Jersey, Alaska, and Australia. In 2008, she incorporated the nonprofit, Outer Banks Center for Dolphin Research, which is dedicated to the conservation of bottlenose dolphins in the Outer banks. For more info, visit obxdolphins.org.