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Gila Trout fish identification, its habitats, characteristics, fishing methods.
The Gila trout is one of the rarest trout species in the United States. The fish was native to the San Francisco, Verde, Gila, and Agua Fria River drainages in New Mexico and Arizona. The Gila trout can grow to about 17-18 inches
The gila trout (Oncorhynchus gilae gilae) is similar to a Cutthroat trout and a native to the Southwest United States, in Arizona and New Mexico. It is an endangered species. The Gila trout has been threatened by competition and hybridization with introduced game fish (such as the rainbow trout). However, the primary cause of reduced Gila trout populations is habitat loss caused by loss of water flow and shade-giving trees, caused in turn by fires, human destruction of riparian vegetation, livestock overgrazing, agricultural irrigation and water diversion, and channelization of streams in the Gila trout's native range.
By the time the Gila trout was listed by the U.S. Fish and Wildlife Service in 1973 its range had reduced from several hundred miles of stream to just 20. After listing USFWS began an aggressive program of stream restoration, removing the introduced trout, restoring and repairing riparian vegetation (to maintain cooler water temperatures), and restocking restored streams with young Gila trout. The species is now more secure than it was in the 1970s, having been moved to 10 new streams, though populations and habitat are still far below those originally established. Conservationists hope to eventually delist the species and allow fishing, thus forming alliances with fishermen in order to help preserve the species.
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The gila trout - Oncorhynchus gilae gilae, is one of two subspecies of trout in Oncorhynchus gilae, the other being the
Apache trout. Both are native to the Southwest United States. The gila trout is a species of salmonid, related to the rainbow and cutthroat trouts. Gila trout are native to the Gila River drainage in New Mexico and Arizona and the headwaters of the Verde River drainage in Arizona.
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Description
The Gila trout and its closest relatives in the Pacific salmon group (
Cutthroat,
Rainbow,
Golden and
Apache) are known as the black-spotted trouts because they are covered with dark blotches, black spots. These spots may cover the entire body or may be more abundant near the tail.
Gila trout have yellowish golden or copper sides that blend to a darker shade of copper on the opercles (gill covers). The small profuse spots on the Gila trout, generally occurring above the lateral line and extending onto the head, dorsal (back, top) fin, and caudal (tail) fin are more suggestive of Coastal Rainbow trout. Spots are irregularly shaped on the sides and increase in size on the back. On the dorsal surface of the body, spots may be as large as the pupil of the fish eye and are rounded. A few scattered spots are sometimes present on the anal fin, and the adipose fin (fleshy fin located behind dorsal fin) is typically large and well-spotted. Dorsal, pelvic, and anal fins have a white to yellowish tip that may extend along the leading edge of the pelvic fins. A yellow cutthroat mark is present on most mature pecimens. Also parr marks, dark blotches that occur along the sides of the body in most salmonid species are absent or faint on Apache trout and sometimes found in Gila trout. Mature Gila trout often have a faint rose color along the lateral line, like Rainbow trout while Apache trout have rose or red colors on their body all life stages. The fins can be bronze-yellow to yellow-orange. The dorsal, pelvic and anal fins have a light-colored leading edge with a white or yellow to orange tip. A faint, salmon-pink band is present on adults, particularly during spawning season when the normally white belly may be streaked yellow or reddish orange. The adipose (fleshy ) fin is rather large and heavily spotted.
Characteristics that distinguish Gila trout from other co-occurring, nonnative trout include the golden coloration of the body, parr marks, and fine, extremely fine and profuse spotting on the dorsal (back) and caudal (tail) fine and spotting that is almost limited to the upper third of the body above the lateral line. These characters differentiate Gila trout from rainbow, brown, and cutthroat trouts. The most apparent distinction from Apache trout is spotting patterns. Apache trout have larger and fewer spots, making them similar to Cutthroat trout.
This fish remains rather small in the streams where it is found, with larger specimens in the range of 12 to 13 inches long. The average length of 6-year-old fish is close to 8 inches, and Gila trout older or longer than this are relatively rare, primarily because of the unproductive nature of the small headwater streams they occupy. Most Gila trout live to about age 5, with a maximum age of 9.
Habitats
Inhabits clear and cool mountain creeks, mountain streams (above 2000 m elevation). Trout need clear, cold water, and their waters began to cloud up with silt and to warm up as the shading vegetation was stripped away. Gila trout inhabit small, cool, clear mountain streams under shady bushes and trees. Deep pools are important for their survival during droughts. Gila trout are now restricted to small headwater streams that typically have fewer deep pools and less suitable overwintering habitat than do larger streams.
Aquatic insects are the primary food of Gila trout. Also adult flies, caddisfly larvae, mayfly nymphs, and aquatic beetles were the most abundant food. Larger fish aggressively guarded their feeding stations and chased away smaller fish. Large Gila trout occasionally consume speckled dace and may also cannibalize smaller Gila trout.
Spawning
Gila and Apache trout, as with
Rainbow and
Cutthroat trout, spawn in the spring when water temperature is rising to 46-47°F (8°C) and runoff flows are declining. Females reach maturity at age 2 to 4 at a minimum length of about 5 in (13 cm). Males typically reach maturity at age 2 or 3. The female Gila trout only spawn once and most males only spawn 2 - 3 times.
The spawning season of Gila trout began when temperatures are 43 to 46°F (6 to 8°C) in early April at the lowest elevation and continued through June at the highest elevation. Stream flow is apparently of secondary importance in triggering spawning activity. Redds were normally in 6-15-cm deep water, about a quarter of the stream width from one bank and within 5 m of cover. The substrate was predominantly gravel and small pebble (0.2 - 4 cm). Spawning fish selected redd sites based on depth of water and substrate rather than on water velocity. Redds ranged in area up to 2 square meters and averaged 3-4 cm in structural depth. Normally a single fish or a pair of fish occupied a redd, but occupancy by 3 to 4 fish was common. A 5 in femail spawns about 70 eggs, and 9 inch (23 cm) female spawn about 300 eggs. Most spawning activity occurred from 56 to 70 days. Fry about 1 inch (15-25 mm) long emerged from gravel nests in 8 to 10 weeks after egg deposition and inhabited riffle areas.
By the end of their first summer, young attain a total length of 2.7 to 3.5 in (70 to 90 mm) at lower elevation streams and 1.6 to 2.0 in (40 to 50 mm) at higher elevation sites. Growth rates are variable, but Gila trout generally reach 7.1 to 8.7 in (180 to 220 mm) total length by the end of the third growing season in all but higher elevation streams. Absence of fry from pools occupied by adults indicated that cannibalism may occur. On average, for every 100 eggs that hatch, only two fish will survive to become adults.
Fishing Methods.
Gila trout is open to fishing year-round, but access to some streams closes at the end of October.
Most usable methods are: Fly fishing using Fly Fishing rods, Bait Casting using
Casting rods, and my favorite
Pole Fishing with extra light, stiff, powerfull and strong Carbon Pole Rods.
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