Desert Pupfish

Distribution:
   The Desert Pupfish was described by Baird and Girard in 1853 They are found in the lower Colorado River drainage of North America from the southern part of the United States to Northern Mexico; southern parts of California, Arizona, and Nevada and as far south as Sonora, Mexico. They inhabit marshes and lakes as well as springs and water holes.
   These fish are very old, biologist refer to them as 'living fossils'. It is evidenced that where the pupfish live was once a series of interconnected prehistoric desert lakes. Around 10,000 years ago these Pleistocene lakes began to evaporate. The pupfish became isolated from one another so the genus, Cyprinodon, developed into various species. Today there are 13 known species, and several subspecies. Many are found only in one specific water hole or pond, making them endemic to that locale.

Status:
   The Desert Pupfish is not listed on the IUCN Red List but it is listed as endangered in California since October, 1980; and is listed as endangered on the federal level in the United States, since March, 1986. Endangerment is caused by habitat destruction/fragmentation and the introduction of none native fish species into their environment.

Description:
   The body of the Desert Pupfish is rather pudgy with a short scaled head and upturned mouth. The fins are rounded and the dorsal fin is set towards the back half of the body. The wild form of this fish is not particularly flashy except for the males when in breeding colors. Males become an iridescent blue when in breeding mode. The females, young, and non-breeding males are an olive to tan color with several dark vertical bars on the sides.  

Size - Weight:
   The female Desert Pupfish will reach about 2 1/2 inches (6.5 cm), and males about 3 inches (7.5 cm).

Care and feeding:
   In the wild Desert Pupfish eats algae, detritus, and aquatic invertebrates. In the aquarium they will eat flakes and frozen food as well as brine shrimp, Tubifex worms, and bloodworms.
   They are an easy fish keep and a 15 or 20 gallon aquarium with a tight fitting lid is recommended. A brackish environment is suggested, created by adding 2 to 3 teaspoons of salt to each two gallons of water. A fine gravel substrate along with some reed type plants will simulate their natural environment. They will require a heater. Provide good filtration and do regular water changes.

Water Region: Top, Middle, Bottom:
   The Desert Pupfish will swim in the middle and lower parts of your aquarium.

Acceptable Water Conditions:
   Temperature: 77 - 95° F (25 - 35° C)
   Hardness: 13 - 19° dGH
   Ph: 7.5 - 8.0

Social Behaviors:
   Desert Pupfish will do best in either a species tank or a community tank with other Pupfish of this same genera, Cyprinodon, or with Splitfins of the Empetrichthys genera. The females and young will school. The males are primarily loners, in the wild they will dig a shallow depression to rest in and chase all intruders away especially when in breeding mode.

Sexual Differences:
   Males become an iridescent blue when in breeding mode and are larger than the females.

Breeding/Reproduction:
   In the wild Desert Pupfish will breed from February through October, whenever the temperature exceeds 68° F (20° C). The male becomes brightly colored and adamantly defends his territory from all but a receptive female. After a short courtship ritual the female lays one egg on the bottom substrate, the egg adheres to the substrate and the male will then fertilize it. Over the course of season, the female may lay hundreds of eggs, but each singly.
   These fish are easily bred in a small tank. Provide water with salt added and include a good amount of spawning mop to protect the eggs. After keeping the male and female separate for several days, introduce them into the breeding tank together. Courtship will start in about an hour or so with a vigorous courtship followed by a spawn. Once the courtship has ended the parents will eat the eggs, so they must be removed promptly.
   The eggs will hatch in 6 to 10 days. The larvae will start to feet the day after they hatch. The newly hatched fry should be fed infusoria, a liquid fry food, or newly hatched baby brine. The fry are easy to raise and will reach full maturity within 2 to 3 months.

Availability:
   As they are endangered, they are not readily available. Check with local authorities about collecting or keeping these fish in your area before obtaining them.