Gila intermedia

Appearance

The Gila chub has a large, chubby body, with large, thick scales. Mature, breeding males have a red or orange color on the lower cheek, back parts of the lips, and on parts of the fin. This coloration can also be found on the male's caudal peduncle (tail side).

Males usually grow to be only about 15 cm (5.9 in), while females can reach to 25 cm (9.8 in)—a significant difference.

Range and habitat

The Gila chub has been found in streams of the Gila River drainage in Arizona, and in the Santa Cruz River system in Sonora, Mexico. Even so, recently, the Gila chub species has not been documented in the San Pedro drainage in Sonora, Mexico. The Gila chub has also been recently discovered in these specific drainages in Arizona: Santa Cruz River, Middle Gila River, San Pedro River, Agua Fria River, and the Verde River. Gila chub of the Gila River basin usually occupies the smaller headwater streams, springs or marshes.

Pins are Wikidata “endemic to” fields. Orange dots, when present, are GBIF occurrence tiles — survey bias included.

Diet and breeding

Gila chubs are omnivores, and their diet mainly includes aquatic (and terrestrial) insects. Juveniles feed throughout the day while the adults are out during the early morning and late night. Juveniles usually consume insects and algae.

Gila chub have a unique breeding season, that occurs from late spring to summer (some populations can go as far as late winter if the water temperature stays constant). The breeding period is long because Gila chub mature in their second or third year, and are more active at this age. Actively breeding fish have distinct intense coloration—parts of the body become fire-red (ventro-lateral surfaces) and the eyes transform to a yellow-orange.

In crisis

Little is known about the population of Gila chub in Mexico, but the populations that reside in Arizona are expected to decrease because of these ongoing threats: aquifer pumping, stream diversion, habitat alterations by non-native crayfishes, and mainly, predation/competition with nonnative fishes. Here, the Arizona Game and Fish Department can complete their status review of warranting the Gila chub under the Endangered Species Act.

Gila intermedia is Endangered on this catalog because that is the IUCN category stored on Wikidata. Confirm the official criteria and any later count on iucnredlist.org.

Sources

Written for this catalog from the English Wikipedia article on Gila intermedia, Wikidata item Q308094. Family and order context is original field-guide writing about the group, not a copied assessment of this one species. Wikipedia text is CC BY-SA. Not an IUCN assessment. Counts, when quoted, can change — confirm them on the recovery programme and on iucnredlist.org.