7601

• UCREFRP Catalog Number: 7601
• Author: Minckley, W. L.
• Title: Native Fishes of Arid Lands
• USFW Year: 1991.
• USFW - Doc Type: A Dwindling Resource of the Desert Southwest.
• Copyright Material: NO

Figure 13. Gila trout, 18.7 cm in total length, Main Diamond Creek, New Mexico. This
endangered species persists naturally in only five streams. Similar to Apache trout,
the species generally remains small in size in the tiny headwater habitats where it
persists.

habitat degradation is an ever present threat to
endemic trout populations. Extensive montane
logging (Fig. 14), both in the United States and
Mexico, has opened stream channels to direct
sunlight, altered patterns of organic input, and

Figure 14. Clear-cutting can impact headwater streams
supporting the threatened Apache trout. Photograph near
the crest of Mt. Ord, Fort Apache Indian Reservation,
Arizona, 1988.

increased erosion and sedimentation. Sawmill wastes
have been a major soutce of organic pollution in
Mexico. Livestock (Fig. 15) compact and denude
marshes and meadows, trample stream banks, and
remove riparian vegetation.

Figure 15. Domestic livestock seek riparian zones for shade,
water, and forage. Their impacts contribute to habitat
degradation through vegetation removal, compaction of
soils, and decreased bank stability.

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