The freshwater fishes of Bermuda:



March 29,2010. The Bermuda Islands possess but a handful of freshwater lakes and ponds. On the main island of Bermuda, the largest bodies of water are Mangrove Lake and Trott’s Pond, both on the east end of Bermuda Island near Harrington Sound. There are also two marshes/ponds near the center of the island, Pembroke Marsh and Warwick Marsh (also called Warwick Pond), and another pond, Evan’s Pond, located on the western end of the island. Finally, there is Walsingham Pond, a sinkhole created when a cave collapsed, but this is essentially seawater; the tidal flux and the organisms inhabiting this pond indicate that there is still a link to the ocean. On nearby St. George’s Island there is a small pond, Lover’s Lake. Of course, these are freshwater only in that they are not directly connected to the ocean — most of Bermuda’s ponds are brackish, if not seawater, although Warwick Pond is reported as “close to being freshwater” according to Dr. David Wingate (as reported by Craig Morfitt here). These ponds are home to two species of Fundulus killifish, both endemic to Bermuda, and one endemic to Lover’s Lake.
Fundulus bermudae is the most widespread of the two species; it is found in Mangrove Lake, Trott’s Pond, Walsingham Pond (West and East), Warwick Pond, and Evan’s Pond (and introduced into Blue Hole Pond). Like many brackish fish, this species is highly adaptable. Unfortunately, the Bermuda Killifish’s adaptibility has not prevented its decline in recent years. In 2003 it was listed as a protected species. According to Wikipedia, the Bermuda Killifish “can grow up to 12.9 centimetres in length and 21.4 grams in weight. The male is dark green with a yellow underside and a dark spot on the dorsal fin when spawning. The female is brown or olive in colour, paler below.”
The other species, Fundulus relictus, is endemic to Lover’s Lake, though this species has, in recent times, been introduced to Bartram’s Pond. Commonly known as the Lover’s Lake Killifish, this species is vulnerable to extinction due to its limited range, though it is afforded a degree of protection since Lover’s Lake is part of a nature reserve.
It is possible that future researchers will determine the various populations of F. bermudae to be separate species.
For a series of pictures taken around Lover’s Lake, check out the local Department of Environment and Natural Resources site.

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