A fundamental tenet of modern ecology and conservation science is that
species occurrence in habitat patches can be determined by patch area and
isolation. But such island biogeographic models often poorly predict
actual species occurrences in structurally complex landscapes that typify
most ecosystems. Recent advances in circuit theory have enhanced estimates
of species dispersal, and through integration with island biogeography,
can provide powerful ways to predict landscape-scale distribution of
species assemblages. Applying such an integrative analytical framework to
43 bird species in Tanzania improved model fit by an average of 2.2-fold
over models where patch isolation was estimated without accounting for
landscape matrix heterogeneity. This approach also allowed us to assess
species-specific dispersal rates and quantify differences among land cover
types in their permeability to animal movement. These results reaffirm the
utility of foundational island biogeographic principles, yet with an
important caveat. Two-thirds of the variance in species occurrence in
habitat fragments can be explained simply by patch area and isolation,
conditional on isolation explicitly accounting for the spatial
configuration of different land cover types in the landscape matrix. 0_usambara1_sites2_isolation_occurrenceNodes_ENodes_WSitesspp_occurraster_east3raster_west3