(full paper is archived in the Miller Library)
Title: Temperature correlated long-term faunal changes in the rocky intertidal
Student Author(s): Gilman, Sarah E
Sagarin, Raphael D
Faculty Advisor(s): Baxter, Charles H.
Location: Final Papers Biology 175H
Date: June 1993
Abstract: Nineteen square yards of W.G. Hewatt's (1934) ecological transect in the intertidal zone at Hopkins Marine Station were replicated in order to determine changes in populations of intertidal invertebrates. Forty-two invertebrate species showed an appreciable change in number between the two studies. It was hypothesized that some of the changes might represent shifts in species' range due to a temperature increase which was observed in historical sea-surface temperature data for the intertidal zone at Hopkins. The species were divided by their listed ranges into northern, southern, and cosmopolitan categories to determine any correlation between changes in a species' population and its listed geographic range. Changes in the physical habitat, introduction of the predator Haematopus bachmani and Enhydra lutris to the area, increases in seagull populations, and increases in Macrocystis were also considered as factors driving the changes in some of the species. When these factors were accounted for, increases in 8 of 10 southern and decreases in 4 of 5 northern species were observed, suggesting a temperature dependent species shift.
Notes: Published in Science, 1995 267:672-675