Tropical Fish Hobbyist - October 2010

Kelly Warm Springs, a naturally heated body of water, sits amid the snowcapped Grand Teton Mountains in Wyoming. Inset: Fish forage in the shallows of Kelly Warm Springs.

the constant warmth of the bubbling water, remain active even in the dead of winter when temperatures beyond the pool can plunge to - 30°F.

hellerii, and guppies Poecilia reticulata. Add a few non-native temperate species such as the tadpole madtom Noturus gyrinus, Utah chub Gila atraria, and goldfish Carassius

A popular anecdote states that the fish were released in 1945 to celebrate the end of World War II. Whether or not this is so, it seems likely that the warm spring

“Prior to…the 1950s, residents of the area released tropical fish into the spring. A popular anecdote states that the fish were released in 1945 to celebrate the end of World War II.”

auratus, and Kelly Warm Springs is indeed a surprising ecosystem.

Prior to Kelly Warm Springs being added to the park in the 1950s, residents of the area released tropical fish into the spring.

had received frequent introductions from people dumping aquarium specimens.

Kelly Warm Springs is also home to a breeding colony of introduced non-native bullfrogs Rana catesbeiana, which, due to

Conservation

While the anomaly of tropical fish and eastern fishes and amphibians is fascinating in juxtaposition with the surrounding environment, it is prudent to note that the introduction of exotic species is one of the greatest threats to aquatic systems. Responsible aquarists know never to release captive specimens into the wild—not only exotics, but even native species that may have picked up foreign diseases or parasites. Adding native fish from other populations can destroy the genetics of wild populations. Many endangered fish species in North America owe their peril, at least in part, to the introduction of exotic species.

Being the premier native sport fish in the Rocky Mountain West, the cutthroat trout Oncorhynchus clarkii (with between 10 and 14 subspecies) has been dramatically reduced across its range by the introduction of non-native salmonids. Yellowstone Lake, historically renowned as the greatest concentration of genetically pure large-spotted or Yellowstone cutthroat trout O. clarkii bouvieri in the world, is now facing a dire threat in the form of the non-native lake trout Salvelinus namaycush.

Thus far, the exotic fish of Kelly Warm Springs are contained in the pond and channel, and some species are probably limited to this range by the low temperatures of the park’s non-heated waters. However, Kelly Warm Springs also contains temperate species such as goldfish, madtoms, Utah chubs, redside shiners, speckled dace, and longnose dace, and these have much greater potential to invade waters beyond the spring. The Utah chub, found in several lakes and rivers in the Grand Tetons and Yellowstone, is native to Wyoming but not to the northwest corner area, making it a non-native exotic in these waters.

Thankfully, the park’s cold waters and long winters have thus far restricted the range of the bullfrogs to the spring itself. Bullfrogs, an eastern species, have been widely introduced into the western United States with catastrophic results for native frog species. It is highly illegal to release or to collect any animal in national-park waters, including Kelly Warm Springs.