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G. L. Hoffman

Publications and source records attributed to G. L. Hoffman.

At least 73 records · Page 4Linked to original sources
USGS1970

A proposed streamflow data program for Oklahoma

An evaluation of the streamflow data available in Oklahoma has been made to provide guidelines for planning future data-collection programs. The basic steps in the evaluation procedure were (1) definition of the long-terms goals of the streamflow-data program in quantitative form, (2) examination and analysis of streamflow data to determine which goals have been met, and (3) consideration of alternate programs and techniques to meet the remaining goals. The study defines the individual relation between certain statistical streamflow characteristics and selected basin parameters. This relation is a multiple regression equation that could be used on a statewide basis to compute a selected natural-flow characteristic at any site on a stream. The study shows that several streamflow characteristics can be estimated within an accuracy equivalent to 10 years of record by use of a regression related to at least three climatic or basin parameters for any basin of 50 square miles or more. The study indicates that significant changes in the scope and character of the data-collection program would enhance the possibility of attaining the remaining goals. A streamflow-data program based on the guidelines developed in this study is proposed for the future.

Open-File Report↗
USGS1970

Control methods for snail-borne zoonoses

All trematodes which cause infections and diseases in humans (zoonoses) require snails for their first intermediate host. Some have additional intermediate hosts such as crustaceans, fishes and frogs. In this paper I have discussed the use of various procedures for controlling snail populations thereby reducing the population of trematodes whose cercariae penetrate the skin of man, or which are acquired by eating raw aquatic vegetation such as watercress, or which cause pathology in fish. Biological, chemical, and physical snail control techniques are discussed. The most promising molluscucides are copper compounds, Bayluscide, biocidal rubber and molluscicidal bait.

Journal of Wildlife Diseases↗
USGS1965

The black-spot (Uvulifer ambloplitis: Trematoda: Strigeoidea) of centrarchid fishes

Adult Uvulifer ambloplitis were recovered from a kingfisher and the worm eggs were incubated. Helisoma snails were infected with the resultant miracidia. Cercariae, very similar, but not identical to Cercaria bessiae, were recovered and used to infect fish. It was possible to infect Lepomis macrochirus, but not Catostomus commersoni, Cottus bairdi, Carassius auratus, Notropis cornutus, N. rubellus, N. spectrunculus, Semotilus atromaculatus, S. corporalis, S. margarita, Ictalurus punctatus, Etheostoma flabellare or Salmo gairdneri. Development of the metacercaria was studied at 13° C, 21° C, and 24° C. There was almost no development at 13° C and development was about twice as rapid at 24° C as at 21° C. The origin of the cyst of parasite origin is discussed. The metacercariae live at least 4 1/2 years in the fish at 12° C. The adult is briefly described and compared with other species. A key to the adults is given.

Transactions of the American Fisheries Society↗