Divers have found a population of the weird and incredibly rare red handfish (Thymichthys politus) during a survey off the Tasmanian coast. The discovery of what is thought to be up to 40 individuals doubles the known population of one of the world’s rarest fish.
Until last week, it was thought that there was only one surviving population of the endangered fish – made up of another 40 or so individuals – living in the waters off southeastern Tasmania. The site from which they were known is tiny, covering just 50 meters by 20 meters (165 feet by 65 feet) – or the size of two tennis courts – and the new location is not much bigger.
The new site is a few kilometers away from the original, which is located in Frederick Henry Bay, although the team that found it are not disclosing the exact location due quite simply to the rarity of the critters.
The distance between the two populations means that they are very likely to be genetically isolated, as the fish are not particularly good swimmers. The fish can do a short burst of around half a meter (1.6 feet) before settling on the bottom again, and tend to use their unsettlingly human-looking hands to maneuver around on the bottom. For a 9-centimeter (3.5-inch) fish, a trek of a few kilometers along the bottom is simply too much of a risk to take.
The new population was found after a member of the public reported seeing one individual on the little reef. Because of the fish’s rarity, a team of seven divers from the Institute for Marine & Antarctic Studies (IMAS) at the University of Tasmania went out to see if they could locate any more, spending two days searching the region.
“We were diving for approximately three and a half hours and at about the two-hour mark we were all looking at each other thinking this is not looking promising,” explained the IMAS’s Antonia Cooper, who was the first to spot the fish. “My dive partner went to tell the other divers that we were going to start heading in and I was half-heartedly flicking algae around when, lo and behold, I found a red handfish.”
Not only does this new discovery mean that the gene pool of the endangered fish has been dramatically expanded, but it also gives hope that more populations of them might be clinging on.
Tasmanian waters were home to three species of endemic handfish. In addition to the red handfish, there is a captive breeding population of the spotted handfish (Brachionichthys hirsutus), while the Ziebell’s handfish (Brachiopsilus ziebelli) hasn’t been seen in a while and is assumed extinct.
Here’s hoping that this little fella has a better run of things.