HSU Master's Theses & Projects
http://hdl.handle.net/2148/8
2024-03-19T13:08:57ZThe parasites of the Botta pocket gopher Thomomys bottae and the taxonomy and biology of Ransomus rodentorum
http://hdl.handle.net/10211.3/217097
The parasites of the Botta pocket gopher Thomomys bottae and the taxonomy and biology of Ransomus rodentorum
Jasmer, Douglas P.
Voge (1955, 1956a) and Frandsen and Grundmann (1961), have identified and recorded the distributions of parasites occuring in pocket gophers of the genus Thomomys. Todd et al. (1971) have identified parasites from Thomomys talpoides. There have been no such studies corncening Thomomys bottae in Northern California. Thus, my initial objective was to identify the parasites of T. bottae near McKinleyville, Humboldt Co., California. As my study progressed, questions arose about microgeographic distributions of the helminthofauna. Therefore, determination. of microgeographical variation became my second objective. Concurrently, a taxonomic problem arose concerning a strongylid nematode, which was tentatively identified as Ransomus rodentorum Hall 1916. Consequently, my
third objective was to clarify the taxonomy of this nematode. Strongylid nematodes commonly infect herbivores (Popova 1964); but R. rodentorum is the only known strongylid parasitizing a subterannean host' and the life cycle is unknown. Thus, my final objective was to describe the life cycle and ecology of R. rodentorum.
Thesis (M.A.)--Humboldt State University, Biology, 1980
1980-06-01T00:00:00ZInstream flow needs study, Kerckhoff Hydroelectric Project, San Joaquin River, California
http://hdl.handle.net/10211.3/216925
Instream flow needs study, Kerckhoff Hydroelectric Project, San Joaquin River, California
Handley, James Michael
An instream flow needs study was conducted on a 12 km section in the foothill region of the San Joaquin River. Most of the flow is diverted for hydroelectric purposes. Four test release flows were maintained for one week each during the summer of 1977. Recording thermographs were used to monitor water temperatures. Weather conditions and water quality parameters were also investigated. A stepwise multiple regression computer program was used to analyze the flow, temperature, and weather data. A survey was conducted to determine the status of the fishery resource.
Each of the test release flows caused the daily maximum water temperature at the downstream stations to drop several degrees. One regression model of maximum water temperature acheived a total explained variance of 89 percent. The ranges of weather variables encountered were not significant in the regression model. Acceptable values of the water quality parameters were maintained under all flow conditions tested.
Smallmouth bass were the dominant species in the study area. Maximum water temperature was the most important smallmouth bass habitat parameter altered by flow releases. A constant release flow of 25 cfs is recommended to maintain water temperatures within the preferred range for smallmouth bass.
Thesis (M.S.)--Humboldt State University, Fisheries, 1979
1979-06-01T00:00:00ZStructure and dynamics of whitebark pine forests in the South Warner Wilderness, northeastern California
http://hdl.handle.net/10211.3/216924
Structure and dynamics of whitebark pine forests in the South Warner Wilderness, northeastern California
Figura, Peter J.
I examined the structural characteristics and population dynamics of whitebark pine (Pinus albicaulis) across a 640 m elevational range in the Warner Mountains, northeastern California. I established permanent plots (8 x 50 m) at 90 m elevational intervals along six systematically located transects. Transects followed an east-west orientation, parallel to the slope. At each plot I inventoried physiographic conditions, stem density, basal area, height, and diameter, and I aged all single-stemmed individuals (>1.4 m) and the largest sound stem of multi-stemmed clusters. I also noted whether each stem occurred individually or as part of a multi-stemmed cluster.
Whitebark pine forest structure and dynamics vary with elevation. At low elevations whitebark pine began expanding downslope into sagebrush steppe habitat in the latter half of the 19th century. These stands are characterized by low stem density and basal area, and by relatively young, small trees. Forests at middle and high elevations exhibit age and size distributions typical of old, self-perpetuating stands. Other structural characteristics (density, basal area, and height) vary between middle and high elevation stands. Whitebark pine regeneration is occurring at all elevations, but sapling and seedling density are uniformly lower than that of tree density.
No differences were detected at different elevations in either the percentage of clustered vs. unclustered stems, or in the number of stems within each cluster. Trees generally occur in clusters more often than saplings, and saplings generally occur in clusters more often than seedlings, suggesting that growth form (single stem vs. multistem) and cluster size may vary within an “individual” over time.
Thesis (M.A.)--Humboldt State University, Biology, 1997
1997-05-01T00:00:00ZZonation, species diversity, and redevelopment in the rocky intertidal near Trinidad, northern California
http://hdl.handle.net/10211.3/216923
Zonation, species diversity, and redevelopment in the rocky intertidal near Trinidad, northern California
Cimberg, Robert
This paper presents the results of a three-year, seven-month field study on the interrelationships among ecological factors, species diversity, and the redevelopment of rocky intertidal zones near Trinidad, northern California.
Thesis (M.A)--Humboldt State University, Biology, 1975
1975-06-01T00:00:00Z