Chesapeake Bay Island Bird Audio, Transect Data, and Code for Nestedness/Modularity Analysis

Two presence-absence surveys were conducted for each island between June and August 2021. Islands were ranked by their characteristics, and each ranked list was evaluated for nestedness and modularity. Compared to a null model, ranking islands by area revealed strong nestedness, ranking by habitat type produced strong modularity, but ranking by degree of isolation did not yield any relationship with nestedness or modularity.

Avian metacommunities on relatively small (<10,000 ha), nearshore (<10 km from the mainland) islands displayed a nested structure along a gradient of island size, and that even on these small islands, different habitat types produced measurably distinct community compositions. The implication is that to preserve biological diversity, one should protect the largest islands with a variety of habitat types.</p>