On Oregon coastal rocky shores, filter‐feeders were relatively abundant and macrophytes were relatively scarce at Strawberry Hill, whereas opposite abundance patterns occurred at Boiler Bay. To determine whether nearshore oceanographic differences were associated with these patterns, we made shore‐based measurements of nutrient and Chl a concentrations. We used a three‐level...
The gonadal steroids, testosterone and estradiol, are known to be important
modulators of neuronal functions and behaviors in most vertebrate species. These
steroid hormones also elicit changes in neuropeptide synthesis and secretion, alter
specific neurohormone receptor levels, and alter neuronal morphology and
electrophysiology. Many of the actions of androgens and...
In a comparison of the mammalian and fish immune systems many similarities and differences are found. While most of the differences occur in the acquired or lymphoid arm of immunity, the nonlymphoid immune systems of fish and mammals share many similarities. For instance, both animal groups use phagocytic neutrophils and...
I examined the biomechanical factors that influence the sizes of intertidal macroalgae by studying a population of Fucus gardneri at Fogarty Creek Point, OR. I constructed a mathematical model to predict optimal sizes and probabilities of survival for Fucus under conditions of high and low wave exposure. Predicted optimal sizes...
To assess the context dependence of kin discriminating
behavior, I examined kin-biased aggregation behavior in tadpoles
of R. cascadae in different ecological conditions. I manipulated food
distribution, predator presence, thermal heterogeneity, and
relatedness in a multifactorial mesocosm experiment. All four
factors interacted to influence tadpole dispersion. My results
suggest that...
The threespot damselfish, Stegastes planifrons,
maintains individual territories that are clustered on
coral patch reefs. My objective was to understand the
effects of territory clustering on behavior and fitness.
Fish with territories in the center of a cluster had
(relative to edge fish): higher mating success (number of
eggs), higher...
The body size (W) of animal species is one of the best predictors of
population density (D) when large assemblages are considered. It has been
shown that theoretically the D-W relationship can be the consequence of two
other distributions: the log-normal distribution of body sizes of the species and
of...
Factors affecting the persistence of mussels (Mytilus californianus) and their associated epibiont species were studied along the central Oregon coast. Interactions between mussels and their algal epibionts (Endocladia
muricata) varied in sign and strength with environmental conditions. In extreme temperatures mussel—epibiont interactions determined survival of individual mussels,
and persistence of...