Patch edge-to-area ratio, not size per se, governs recolonization rate

Evidence

Perhaps the most obvious influence of patch size on colonization derives not from the size of a patch per se but from the manner in which the ratio of patch perimeter length to area changes with patch size. This effect is probably most important for type 1 patches cleared in assemblages of species that are able to invade by lateral movement of individuals or by vegetative ingrowth of clones. The rate at which clearings in mussel beds are filled by the lateral encroachment of adults is affected by a variety of features of the patch environment [e.g., depth of the surrounding bed, angle of the substratum (Paine and Levin, 1981)]. All else being equal (includ­ ing patch shape), however, smaller patches have a greater ratio of edge to area and are therefore closed by the lateral encroachment of mussels at a correspondingly higher rate (Paine and Levin, 1981; Sousa, 1984). Very large clearings in mussel beds are recolonized primarily by settlement of larvae from the plankton. — S. T. A. Pickett and P. S. White, eds., The Ecology of Natural Disturbance and…, 764