Crosses were made between a stock of summer steelhead (Salmo
gairdneri) known to be resistant to infection by Ceratomyxa
shasta and stocks of summer steelhead known to be susceptible.
Ceratomyxosis, the disease caused by C. shasta was initiated by
exposure to Willamette River water. I found that the crosses
were...
The new closed season for commercial crab fishing in Oregon went into effect in 1948. This 1949 document summarizes the results of the 1948 closure and details research and procedures being used to refine the closing dates. This document provides a good look at earlier methods of natural resource management...
Fishery researchers have attempted to preserve viable fish sperm for extended periods of time. Only limited success has been achieved with storage of spermatozoa from salmonids. The principal accomplishments of this investigation during the fiscal year 1966-1967 were the development of standard methods for the collection
and evaluation of fish...
The lower Deschutes River of northcentral Oregon has a historically uniform discharge record. Significant reductions in discharge below the seasonal norms will degrade the environment for migratory and resident salmonids by increasing siltation and gravel compaction, and by reducing intragravel water dissolved oxygen content. Fish spawning will be limited by...
This report measures the effects of logging on the production and yield of Coho salmon, coastal cutthroat, and steelhead trout in small coastal streams. It contains descriptions of the physical and biological environment before logging, and describes some immediate effects of logging, such as such as a decrease in dissolved...
Fresh fish trade in Kribi, Cameroon is characterized by high uncertainty in a context of specific assets. Facing this uncertainty, actors have developed hybrid coordination mechanisms centered on contractual arrangements and networks. These implicit contractual arrangements involve price negotiation, delivery agreements between fishermen and buyers, as well as transactions including...
This study examines income generation potential and resource- use efficiency of aquaculture farms in Nigeria. A total of 120 aquaculture farms were sampled. Using gross margin (GM) analysis, the result shows that, all the sampled farms were able to cover their total operating expenses with an average GM > 200,000...