More from Myrtle the Turtle

MRB: How long was she at the Provincetown aquarium?

SFC: That we don’t know. As you can imagine, record keeping was a little shoddy back in those days. She could have been in captivity most of her life. The goal of this aquarium, and probably most aquariums, is to release endangered sea turtles. But some turtles have obvious reasons for not being releasable. Myrtle is not so obvious. She has no notable health issues or injuries that would prevent her from being released in the wild, but just based on her behavior that I’ve been telling you about…I mean she’d be swimming up to every swimmer, snorkeler, diver, boat, or shark, and she would not know to go find food on her own. So we are certain that she would perish if we released her. It’s in her best interest to keep her in captivity.

MRB: When an animal has been here 40 years, she has probably gone through a lot of reproductive cycles. Not to sound weird, but does she have a sexual history? Do turtles have some version of going in heat?

SFC: Well, there was a male sea turtle at one point named Blackie. According to our records, he was a donation from the Montreal aquarium and arrived here in August 1970. He was here all through the ‘80s, and in July of 1991, Blackie was transferred to the Pittsburgh zoo. The reason was that he aggressively pursued Myrtle during the breeding season, which comes in the early spring and summer every other year. Let’s just say Blackie was very interested in Myrtle, and the feeling was not mutual. He really just chased her around endlessly, could not take a hint, and it got to the point of her being really stressed out. It was probably the only time she wasn’t in complete control. So unfortunately, Blackie had to go away.

MRB: How does Myrtle behave when that breeding season comes around?

SFC: There are behaviors that we recognize as behaviors that we would see in wild sea turtles during that mating season. There are physiological cues and environmental cues, and most scientists would agree it’s a combination of both that provokes a sea turtle to go into that fasting mode. What’s interesting at the aquarium is that we don’t have the environmental cues, which would be a change in light and maybe water temperature. So that says to me that these turtles could depend solely on physiological cues.

Something goes on in a female turtle’s body; egg follicles are starting to develop. With ultrasound, we can actually see the development of follicles and know, “Okay, this turtle is in breeding mode.” Then you’ll see Myrtle start to fast, and you’ll just see her swimming and swimming, and resting and swimming, and swimming and resting, and this is because in the wild she would now be leaving the feeding ground for the breeding ground. It’s very routine, almost every two years around this time of year. And it’s always preceded by her appetite being through the roof, which is maddening for us, because under normal circumstances she has a huge appetite, and right before this season, she’s out of control. That’s when she does the bulk of her shark–food stealing, and that’s when she’s at her worst in terms of getting herself into trouble over her appetite. But then it starts to wane, and then her fast is exactly like what would be happening if she were in the wild.  This period can last anywhere from three to six months.