Scientific name: Xyrauchen texanus,
The razorback sucker is one of the largest suckers in North America; larger fish may weigh as much as 12 to 14 pounds and may be 40 years old.
This extremely rare, large-river species is found only in the Colorado River basin.
The razorback sucker is distinguished from all other fishes by its abrupt, keel-edged, bony hump that rises on the back immediately behind the head.
Its unusual body shape suggests a design suited for life on the bottom in turbulent flows.
Reproductive failure or poor survival of young fish are believed to be the primary reason for the decline of this species.
Maximum length: 24-36 inches.
The razorback sucker has a large head which is some what compressed, constituting about one fourth of the total length. Its eyes are small and longitudinally oval. It has a large mouth, and distinctivenuchal hump. The dorsal fin is long and low, and it has a large, powerful caudal fin. The fish's upper surface is dull slate coloring, its belly is white, and its throat is yellow.
- The razorback sucker is a spring spawner. Male breeding coloring is black to a point about one inch below the lateral line, with a brilliant orange extending ventral from this point.
- The razorback sucker's diet consists of vegetable matter and material from river bottom ooze.
- Changes in stream flow and water temperatures, direct loss of habitat due to inundation by reservoirs, blockage of migration routes and the introduction of non- native fish species are primarily responsible for the decline of the razorback sucker. The Recovery Program agreement, signed in January 1988, includes 5 basic steps to aid in the recovery of the species.
1. Provision of instream flows
2. Habitat development and maintenance
3. Native fish stocking
4. Management of non- native fish species and sport fishing
5. Research, monitoring, and data management
The goal of this program is to maintain and protect self- sustaining populations and sufficient natural habitat to sustain these populations. This program should be beneficial to other endangered fish species sharing this habitat, including bonytail chub, Colorado squawfish, and humpback chub.