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Publications

Filter Total Items: 1994

Diet and morphology of extant and recently extinct northern bears

I examined the relationship of diets to skull morphology of extant northern bears and used this information to speculate on diets of the recently extinct cave (Ursus spelaeus) and short-faced (Arctodus simus) bears. Analyses relied upon published skull measurements and food habits of Asiatic (U. thibetanus) and American (U. americanus) black bears, polar bears (U. maritimus), various subspecies of
Authors
David J. Mattson

Changes in mortality of Yellowstone's grizzly bears

Records of grizzly bear (Ursus arctos) deaths are currently used by managers to indicate trends in actual grizzly bear mortality and to judge the effectiveness of management. Two assumptions underlie these current uses: first, that recorded mortality is an unbiased indicator of actual mortality, and second, that changes in mortality after implementation of management strategies are sufficient grou
Authors
David J. Mattson

Amphibians of the Fort Lewis Military Reservation, Washington: Sampling techniques and community patterns

The 27,000 ha Fort Lewis Military Reservation is situated in the Puget lowlands and contains a wide variety of aquatic habitats offering potential refuge for native amphibians. We surveyed amphibians on Fort Lewis from 1992 through 1995 to examine occupancy patterns relative to wetland characteristics. We documented 9 native amphibians and 1 introduced anuran (Rana catesbeiana) that represent 133
Authors
M. J. Adams, R. Bruce Bury, Scott A. Swarts

Photosynthesis of the cyanobacterial soil-crust lichen Collema tenax from arid lands in southern Utah, USA: Role of water content on light and temperature responses of CO2 exchange

1. The gelatinous cyanobacterial Collema tenax is a dominant lichen of biotic soil crusts in the western United States. In laboratory experiments, we studied CO2 exchange of this species as dependent on water content (WC), light and temperature. Results are compared with performance of green-algal lichens of the same site investigated earlier.2. As compared with published data, photosynthetic capa
Authors
Otto L. Lange, Jayne Belnap, H. Reichenberger

Reconstructing the spatial pattern of trees from routine stand examination measurements

Reconstruction of the spatial pattern of trees is important for the accurate visual display of unmapped stands. The proposed process for generating the spatial pattern is a nonsimple sequential inhibition process, with the inhibition zone proportionate to the scaled maximum crown width of an open-grown tree of the same species and same diameter at breast height as the subject tree. The results of
Authors
M.L. Hanus, D.W. Hann, D.D. Marshall

Experimental analysis of trout effects on survival, growth, and habitat use of two species of western Ambystomatid salamanders

Introduced fish have been implicated as reducing abundance or eliminating ambystomatid salamanders from montane lakes in western North America. We tested the null hypotheses that survivorship, growth, and refuge use of larvae reared for 30 d did not differ between artificial ponds with trout and without trout. Larval survivorship for both A. macrodactylum and A. gracile was significantly lower in
Authors
T. Tyler, W.J. Liss, Robert L. Hoffman, L. Ganio

Stenocybe fragmenta, a new species of Mycocaliciaceae with fragmenting spores

The new species Stenocybe fragmenta (Ascomycota, Mycocaliciaceae) is described from western North America. The species was collected from twigs of Cercocarpus montanus and Rhamnus purshiana. Stenocybe fragmenta is characterized by 5-7 septate, 18-30 I?m long ascospores that fragment at maturity. This is the first report of spore fragmentation among the Mycocaliciaceae.
Authors
E.B. Peterson, Jouko Rikkinen

Bryophyte species associations with coarse woody debris and stand ages in Oregon

We quantified the relationships of 93 forest floor bryophyte species, including epiphytes from incorporated litterfall, to substrate and stand age in Pseudotsuga menziesii-Tsuga heterophylla stands at two sites in western Oregon. We used the method of Dufrêne and Legendre that combines a species' relative abundance and relative frequency, to calculate that species' importance in relation to enviro
Authors
T. Rambo, Patricia S. Muir