Date:12/12/25
Today's fish of the day is the railroad valley springfish!
The Railroad Valley springfish, named after Nevada's Railroad Valley, scientific name Crenichthys nevadae, is an incredibly endangered species. Found exclusively in Nevada across the hot springs of Railroad valley, this fish is native to only 7 separate and distinct hot springs. Although in the modern day we've introduced them to 2 other hot springs, after these fish were severely threatened by the introduction of game fishes. Found occurring naturally within: Big Warm spring, Little Warm spring, Big spring, Hay Corral spring, North spring, Reynolds spring, and Duck water spring where the original population is extinct, with only introduced springfish remaining. There are also Railroad Valley springfish within introduced springs, those being: Soda spring, Terrace hot spring, and Chimney hot spring (see photo of general locations of these below). Within these springs, the Railroad Valley springfish lives in shallow waters over gravel or vegetation. These fish live in an amazing temperature range of 77-102 degrees F (25-39 C), however they can over heat. If water temperature are above 102 ° F, or sustained at 102, these fish will become increasingly distressed and eventually die. This is often prevented by these fish swimming out of the shallow waters they prefer and into deeper, cooler pools.
Despite living in such a confined space, with little food, the Railroad Valley springfish manages. Their diet consists of both various zooplankton, smaller fish, crustaceans, and mollusks, but is also made up of a large part of algae. During the year as summer arrives and more creatures live in the springs, the Railroad Valley spring fish feasts upon the zooplankton. Once fall, winter, and spring arrive these fish persist on algae until they can acquire animal proteins once more. This diet supports these fish to reach a very tiny 48mm long, that is 4.8 centimeters. Despite previously having few predators, due to the introduction of several game fish, and other invasive species now predate heavily on these fish.
The reproduction of these fish is relatively unknown, beyond broad strokes. The Railroad Valley springfish breeds year round, albeit less in the spring and fall, to not at all in the winter, with most breeding occurring in the summer. Though, these fish refuse to breed if the water grows above 95 °F, but prefer waters above 86 °F. Female fish will release between 10-17 eggs per spawning event, each incubating only 5-7 days before larval Railroad Valley springfish hatch. Only 5mm long. The lifespan of these fish is unknown, but is likely around a year if not less.
That's the Railroad Valley springfish! I hope you enjoyed learning about them!