REDISCOVERED FISHES

When writing these pages I often feel like an old-fashioned harbinger of doom - like one of those
sad old blokes who used to hang around outside Leicester Square Tube Station brandishing a
placard which informed the world that “The End is Nigh!”.

Many fish species that have become extinct within the last few years. Sadly, the list continues to grow each year. But it’s not all doom and gloom; new species are discovered regularly, and species thought to be extinct are also sometimes
rediscovered.

The Dwarf Loach, Chain Botia, or Chain Loach (Yasuhikotakia sidthimunki, formerly Botia
sidthimunki) is a popular freshwater tropical fish in aquariums and belongs to to the Cobitidae family. It grows up to 3in in captivity, and 5in in the wild. It prefers water with temperature 77 to 86F (25 - 30C), pH 6.5 to 6.9 dGH to 8.0. It is omnivorous with diets including live crustaceans, insects, snails, etc. The Dwarf Loach is found in the Mae Klong river and River Kwai, Western Thailand. This species is endangered and is a protected species in Thailand. It was thought to be extinct in the wild until recently rediscovered in Sangkhla Buri.

Algansea barbata, the Lerma chub, is found in the headwaters of the headwaters of the Rio Lerma, Mexico. Algansea barbata was last collected in 1964, and last seen only eight years later, but its extinction was not suggested until 1998. However eight specimens (five males and three
females) of Algansea barbata Alvarez and Cortés, 1964 were caught in a lateral channel to Rio Sila, Tiacaque, Jocotitlán, State of Mexico (19º 40' N and 99º 42' W) in April of 1999. This extends the known range for the species in the State of Mexico toward the most southern population's northeast limit (13 Km to the NE of Ixtlahuaca, on highway 55, NNW of Toluca, State of Mexico) and it is the first record since 1972

The parasitic Miller Lake Lamprey (Lampetra minima) was thought to have gone Extinct in
about 1958. This was as a result of a deliberate chemical treatment of Miller Lake (the only
known location at the time) to exterminate this species to prevent predation on introduced trout fingerlings. However, in 1992, an adult lamprey collected in the Williamson River was identified as L. minima, and, in 1996, unidentified lamprey were collected in Miller Creek, the outflow stream of Miller Lake. Subsequent surveys in the summers of 1997–1999 reconfirmed the species extinction in Miller Lake but lead to the discovery of several subpopulations of L. minima within and outside the Miller Lake sub-basin (Lorion et al. 2000).

The rediscovery of this species was only brought to the attention of the IUCN Red List Programme in 2004. It is provisionally listed as Data Deficient - pending a reassessment of its status.

Formerly thought to be endemic to Miller Lake (16km northeast of Mt. Thielson), Klamath County, Oregon. Recent surveys documented subpopulations in Miller Creek, Jack Creek, and the upper sections of the Williamson and Sycan rivers (Lorion et al. 2000).

In 2002 biologists with Conservation Fisheries, Inc. (CFI), a Knoxville-based non-profit organization, recently found a single specimen of the slender chub while conducting a fish survey in northeast Tennessee. This find is the culmination of years of hitherto-fruitless searching.
"We were ecstatic," said Pat Rakes, co-director of CFI, "It's a wonderful feeling to be out there for so long, searching and searching, and then coming up with something."

The slender chub, a federally protected fish, is known only from the Clinch and Powell Rivers in
northeast Tennessee and southwest Virginia. It was last seen in the Clinch River in the mid-
1990s; it hasn't been seen in the Powell River since the early 1980s.

The lone fish, about the length of a human finger, is now in an aquarium at CFI's headquarters,
eating voraciously, while biologists hope to find a mate to begin the propagation process. The biologists at CFI have been key players in efforts to restore the aquatic biodiversity of the
Southern Appalachians. Their Knoxville facility, with its numerous aquariums full of rare and
imperilled fishes, is the site of captive propagation efforts being carried out for numerous fish species.

A rare fish that had not been seen by scientists for over 50 years has been rediscovered in
Auckland, New Zealand. The threatened Black mudfish, Neochanna diversus, is listed on the
current IUCN Redlist for fishes, but hasn't been seen since shortly after the species was originally described in 1949. However, a recent survey of the Te Henga and Tomarata wetlands revealed a population of Neochanna diversus alive and well.

Grant Barnes, Project Leader for Auckland Regional Council's State of Environment monitoring programme says that the new discovery of Neochanna says a lot about the health of the ecosystem. He told the news website Scoop: "Freshwater fish are sensitive to a wide range of environmental impacts such as habitat loss, pollution and sedimentation."

Neochanna diversus is a galaxiid, and a member of the Osmeriformes order. It gets its common name from its ability to spend part of the year in a state of aestivation when its pool dries up.

So it ain’t all doom and gloom. The natural world still has plenty of surprises in store for
us. Watch this space...