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<br />282
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<br />
<br />FISH CULTURE IN FISHERIES MANAGEMENT
<br />
<br />1979, Rinne 1985, Rinne and Minckley 1985).
<br />Performance of the fish in a hatchery environment
<br />suggests that reasons for decline are perhaps much
<br />more comple~ and multiple in nature. Angler
<br />harvest and habitat degradation conceivably would
<br />have serious impacts on a wild Apache trout
<br />population that has low recruitment because of
<br />low fecundity and fry survival. Further, a fish that
<br />is apparently a known slow grower in a hatchery
<br />may not be able to compete with a faster growing
<br />non-native salmonid in the wild. Larger-sized
<br />introduced salmonids, of the same year-classes as
<br />the natives, may effectively dominate the preferred
<br />habitat and displace the natives in the wild (Rinne
<br />et al 1981).
<br />Recently, the FWS has assumed the responsi-
<br />bility of further refining techniques for rearing
<br />Apache trout at the Williams Creek NFl(, Ari-
<br />zona. The practice of taking eggs from wild fish,
<br />and improved breeding methods, have resulted in
<br />increased survival and growth of hatchery-reared
<br />fish.
<br />
<br />Summary
<br />
<br />It has been only a decade since strong federal
<br />legislation has provided a mechanism to effectively
<br />conserve declining animal and plant resources.
<br />During this period, primary activities under the
<br />Endangered Species Act of 1973 were devoted to
<br />listing "threatened" and "endangered" species
<br />and preventing federal agencies (and individuals)
<br />from impacting designated species and their hab-
<br />itats. Only within the past several years have
<br />progressive recovery actions come to fruition.
<br />The multispecies endangered fish facility at
<br />Dexter, New Mexico, is the first of its kind in the
<br />United States, and progressive activities there are
<br />playing a major role in the recovery of native
<br />southwestern fishes. Additional mono-species
<br />hatcheries, such as those for the Apache trout and
<br />cui-ui, are equally important. In addition, exten-
<br />sive small-scale artificial propagation of individual
<br />species by researchers and interested biologists at
<br />various agendes and universities is not uncommon.
<br />Varying success has been achieved with artificial
<br />rearing of respective species.
<br />The different levels of intensity and size of
<br />artificial propagation units combined ":ith suc-
<br />cesses and failures to date demonstrate the need
<br />for effective coordination of efforts and detailed
<br />documentation of cultural techniques by the var-
<br />ious individuals and agencies. For example, ra-
<br />zorback sucker, Colorado squawfish, Gila top-
<br />
<br />minnow, and cui-ui are relatively easy species to
<br />propagate. By comparison, the woundfin and
<br />Apache trout have been difficult species to prop-
<br />agate successfully. The relative importance that
<br />hatchery propagation may play in the conservation
<br />of respective species has to be carefully considered
<br />and not universally applied.
<br />Hatchery propagation can playa positive role
<br />in the management of rare native species of fishes.
<br />Dexter NFH is evidence that this approach is
<br />politically and operationally feasible in the con-
<br />servation of our native fishery resources in the
<br />American Southwest. Several philosophical ques-
<br />tions must be considered relative to the role that
<br />artificial propagation may play. First, are multi-.
<br />species, primary facilities such as at Dexter pref- .
<br />erable to monospecies, secondary activities as
<br />occurred at Sterling Springs, Arizona.? The former
<br />modus operandi has more clearly defined objec-
<br />tives and goals, but incurs problems inherent to
<br />multiple species propagation. By comparison,
<br />propagation in the latter type of facility normally:
<br />is carried by the primary hatchery program and;.
<br />therefore, is subject to both political and opera-
<br />tional problems. A secondary propagation' ap-
<br />proach is better than none at all, yet,. planning
<br />and goal setting for a particular species is much
<br />more tentative under such a scheme. Another
<br />equally or perhaps more important question to
<br />ask is whether a species ought to be propagated
<br />in a hatchery or simply transplanted from one
<br />wild habitat to another, thereby circumventing
<br />the artificial hatchery environment?
<br />Basic to the question of artificial propagation
<br />is the status of the respective species in the wild.
<br />Minckley and Deacon (196~) disc~ssed the varying
<br />nature of species endangerm~nt :th~t is\pertinent
<br />here. If a species occurs in a single disjunct
<br />population in the wild (e.g., Devil's hole pupfish,
<br />Cyprinodon diabolis), and its habitat is threatened
<br />with loss, then transferral to a hatchery, is an
<br />essential step to survival of that species. As such;
<br />the hatchery serves as a refugium while, at the
<br />same time, permitting potential development of
<br />culture techniques, propagation to increase num-
<br />bers, and research into basic life history about
<br />which very little is often known. The. cui-ui;
<br />bony tail , and Chihuahua chub are examples of
<br />species for which hatchery propagation is prereq-
<br />uisite for survival. The razorback sucker, Colorado
<br />squawfish, and humpback chub, although not.
<br />occurring in singular localities in the wild, certainly. .
<br />will require artificial propagation if ~t. Ii
<br />, . ," .;A'dJ::~f
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