Fire-history reconstructions are based on tree-ring records that span the last few centuries and charcoal data
from lake-sediment cores that extend back several thousand years. The two approaches have unique strengths and
weaknesses in their ability to depict past fire events and fire regimes, and most comparisons of these datasets...
Conservation conflicts may develop on restoration sites with multiple species recovery objectives. For example, on Pacific Northwest prairies, the co-planting of the diploid cytotype of the common native wildflower Castilleja hispida with the endangered wildflower C. levisecta has resulted in putative Castilleja hybrids on restoration sites, prompting fears that genetic...
Understanding how populations within a species interact across various geographic and temporal scales is fundamental to developing appropriate conservation strategies. I examined the geographic variation in genetic and meristic characters of coastal cutthroat trout (Oncorhynchus clarki clarki) based on
approximately 1,400 fish sampled from 54 populations spanning their distributional range...
Hybridization has been identified as a significant factor in the evolution of plants as groups of interbreeding species retain their phenotypic integrity despite gene exchange among forms. Recent studies have identified similar interactions in animals; however, the role of hybridization in the evolution of animals has been contested. Here we...
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Catostomid Fishes
Thomas E. Dowling1¤a*, Douglas F. Markle2, Greg J. Tranah3¤b, EvanW. Carson1¤c, David
W
The process of plant speciation often involves the evolution of divergent ecotypes in
response to differences in soil water availability between habitats. While the same set of traits
is frequently associated with xeric/mesic ecotype divergence, it is unknown whether those
traits evolve independently or if they evolve in tandem as...
If the success of the Endangered Species Act (ESA) is measured by the number of endangered species that have been recovered and delisted, then the act is not very successful. Only 15 species have been delisted because of recovery in the history of the ESA. The Borax Lake chub (Gila...
Native freshwater fish biodiversily is imperiled in Oregon with 36 species
or sub-species listed by the State of Oregon as sensitive, threatened, or endangered, and
9 species or sub-species listed as endangered or threatened under the federal
Endangered Species Act. Understanding and managing biodiversity is critical to its
conservation. Using...
Considerable controversy exists about how fish assemblages are
organized. I explicitly took fish movement into account while I
studied the effects of disturbance, habitat complexity, and predation
at different times of the summer to understand the major factors
influencing assemblage structure in a high desert Oregon stream. The
effects of...
Native bees are important ecologically and economically because their role as pollinators fulfills a vital ecosystem service. Pollinators are declining due to various factors, including habitat degradation and destruction. Grasslands, an important habitat for native bees, are particularly vulnerable. One highly imperiled and understudied grassland type in the United States...