PARENT SESSION
Symposium 5: Marine macroecology
Organized by: JD Witman and K Roy
Tuesday, August 9, 8:00 AM - 11:30 AM, Meeting Room 517 B, Level 5, Palais des congrès de Montréal
The impacts of dispersal on marine macroecology.
Sagarin, Raphael*,1, Gaines, Steven2, Gaylord, Brian3, Kinlan, Brian2, Lester, Sarah2, 1 University of California Los Angeles, Los Angeles, CA2 University of California Santa Barbara, Santa Barbara, CA3 University of California Davis, Bodega, CA
ABSTRACT- Untangling the causes of patterns in species' geographic ranges poses many daunting challenges. The relevant spatial and temporal scales are large, detailed data are often scarce, and the tool chest of approaches for testing hypotheses is limited. One source of growing insight comes from macroecological comparisons across species with different life history traits. In marine ecosystems, variation in the mode of reproduction is widespread and generates enormous variation in key demographic features such as the scale of dispersal. Here we use contrasts in several aspects of the geographic range -- e.g., its size, location, and internal distribution of individuals -- among species with different modes of reproduction to examine several hypotheses about the role of dispersal in geographic ranges. We find evidence for strong influences of dispersal distance on some range features (e.g., the location of range boundaries) and surprising little influence of dispersal on others (e.g., range size). Additionally, theoretical work suggests that dispersal may play an important role in determining distributions of species abundance across the range. Thus, dispersal may provide a potential explanation for the unexpected patterns of high species abundance near range edges that we found in previous field surveys.
Key words: dispersal, distribution, range, boundaries