Throughout the summer of 2015 and spring of 2016 multiple observations were made of an undocumented species for the waters of St. Eustatius, the lemon shark. All observed individuals were estimated to be smaller than 65 cm in total length. The observations were officially described in a new short note by Guido Leurs, Erik Boman, and Paddy Walker.
Guido Leurs writes about the observations in his personal blog: “It all began when I joined a trip organized by Save Our Sharks, a project of the Dutch Caribbean Nature Alliance to conserve sharks in the waters of the Dutch Caribbean. The trip brought us to Statia, where I met up with two of the owners of the Scubaqua Dive Center, Mike Harterink and Menno Walther. Mike shot a couple of pictures of a young shark in the shallow waters near the dive center. In addition, Menno shot a short video of two young sharks cruising in the same area. The young sharks observed on both occasions happened to be young lemon sharks (Negaprion brevirostris), a species that has not been documented before in the waters of this Caribbean island.
All of the observed lemon sharks were estimated to be between 50 and 65 cm. This is close to the size at birth for lemon sharks, which is a length of 60 to 65 cm. Throughout their life, these sharks can grow to a whopping length of 3.40 meters (although individuals of 2.40 meters are more common) and reach an estimated age of at least 25 years. Like many other shark species, lemon sharks reach maturity relatively late in their life, at an age of 12 to 16 years. Female lemon sharks give birth every other year to a litter of 4 to 17 pups, after a gestation period of 10 to 12 months. The pups will remain in the area of where they were born for several years. This behavior is known as natal philopatry (i.e.tendency to return to a specific area).
These observations only indicate that the shark use the waters of Statia. Where they come from remains speculation.There are two possibilities: (1) the sharks were born in these waters and remained in the vicinity of the island, or (2) the sharks were born elsewhere and visit Statia now and then. Before going into detail on both possibilities, I would like to stress that these observations are merely an indication for future research and do not prove that Statia’s waters act as a nursery or vital area for this species.”
You can read the short note that was published on the Science Matters platform, or read more about the subject on Guido’s blog.