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At least 19 recordsLinked to original sources
USGS1947

Disease control in hatchery fish

A direct method for controlling diseases among hatchery fish has long been sought as an alternative to the earlier technique of hand dipping. A simple, practical, effective method of direct pond treatment not only obviates all need for handling fish weakened by disease, but it would materially reduce the time and effort required by hatcherymen in keeping diseases under control. Furthermore, a direct pond treatment could be used for routine prophylaxis to eradicate diseases during their incipient stages--long before their presence becomes apparent. Several methods for applying direct pond treatments in coldwater-fish culture have been proposed. Kingsbury and Embody (1932) developed a technique for applying disinfectants directly to the inflowing water of a pond. Later, Fish (1939) advocated a method involving the recirculation of a disinfecting solution through a fish pond. For various reasons, neither of these methods proved to be an effective answer to the problem of controlling hatchery diseases and neither became widely adopted. The method described herein has been extensively tested, both in the laboratory and at the producing hatchery, over a period of several years. Once familiarity with the details of application have been mastered, th8 reduction in effort required to treat fish is amazing. For example, two men have treated 20 large ponds containing several million fish, in one morning with no significant increase in mortality of the fish, whereas a crew of eight men required a full day to treat a single similar pond by hand dipping the fish with a subsequent loss approximating 50 percent of the stock.

Fishery Leaflet↗
USGS1970

A brief history of commercial fishing in Lake Erie

Salient features of the development of the industry from about 1815 to 1968, changes in fishing gears and methods, changes in the kinds and abundance of fishes caught, and the attendant effects of disappearing species on the stability of the fishery are described. The history and present status of the walleye, yellow perch, and eight other fishes, still taken in commercial quantities, are presented in more detail and are considered in the context of their effect on the current moribund state of the U.S. fishery. Past and present contributions of Lake Erie's tributaries and northerly connecting waters to the fishery are outlined briefly. The "outlook" for the fishery under present conditions of selective overfishing for high-value species, excessive pollution, ineffective and uncoordinated regulation, and antiquated methods of handling, processing, and marketing fish are discussed, and possible solutions to these problems are suggested.

Lake Erie↗
USGS1966

Plankton

No abstract available.

Fishery Leaflet↗
USGS1959

Fish mycobacteriosis (Tuberculosis)

The etiologic agent for the bacterial disease, "fish tuberculosis" (more correctly "mycobacteriosis"), was first observed in carp in 189& from a pond in France. Subsequently similar agents have been isolated from or observed in fish in fresh water, salt water, and brackish water, in fish in aquaria, hatcheries, and natural habitat~ (wild populations of fish). The disease has been recognized as an important infection among hatchery reared salmonid fishes on the West Coast of the United States, and in aquarium fishes such as the neon tetra, the Siamese fighting fish, and in salt water fish held in zoological displays.

Fishery Leaflet↗