PARENT SESSION
Oral Session #12: Aquatic Ecology: Marine.
Presiding: R. Lewison
Monday, August 5. 8:00 AM to 11:30 AM. Mesquite Room, Radisson.
Exposing the scales: an extensive spatially nested survey to uncover predominant scales of variation of rocky intertidal species.
Allison, Gary*,1, Kavanaugh, Maria2, Solhstrom, Sheri2, Wood, Spencer3, Schoch, Carl4, Menge, Bruce2, Lubchenco, Jane2, 1 The Ohio State University, Columbus, OH2 Oregon State University, Corvallis, OR3 University of Canterbury, Christchurch, New Zealand4 Kachemak Bay National Estuarine Research Reserve, Homer, AK
ABSTRACT- Elucidating patterns of species distribution and their relationship to cross-scale processes within a geographic context requires extensive and consistent sampling across the geographic range of interest. Here, we report on the patterns uncovered in a spatially nested survey of rocky intertidal species of the West Coast of the US. This program, one component of the Partnership for Interdisciplinary Studies of Coastal Oceans (PISCO), is designed as a long-term assessment of communities at multiple spatial scales spanning transect-level to region-level (100's of km) patterns. Our surveys range from Cape Flattery, WA to San Diego, CA and encompass several purported biogeographic breaks. These annual surveys record abundance of over 250 species or composite taxa across 14 phyla (mostly invertebrates and algae) representing a wide variety of life-history strategies, functional groups, and commonness/rarity levels. Analysis in-progress suggests that recorded patterns often do not support generally assumed patterns of distribution and abundance. For example, although about half of the species show the expected uniformly decreasing frequency/abundance relationship, many are strongly unimodal suggesting contagious distributions. These data are useful to characterize a variety of species distributions at range edges, at both distinct and 'leaky' biogeographic boundaries. Because of the survey's explicit spatially nested design, analysis reveals predominant scales of variation across space and even time.
KEY WORDS: Species distribution, Biogeography, Spatial scales, Rocky intertidal biodiversity