Habitat Loss Results

Many of the >300 waterbird colony islands on the Texas coast are eroding rapidly, and colonial waterbird breeding habitat is decreasing statewide. Meanwhile, coastal resource managers are investing millions of dollars per year into habitat restoration. But without estimates of island-specific trends in habitat loss, resource managers will not be able to assess the consequences to regional bird populations or know how much time they have left to act. We used aerial images from four years during 1995–2018 to delineate nesting habitats for colonial waterbirds at 300 islands in all major bay systems in Texas. We quantified the rate of habitat loss for ground and tree nesting birds as a function of island traits, including size and percent vegetation cover. Overall, 88% of islands lost supratidal habitat; moreover, bare substrate declined at a rate of 2.5% ± 2.7% per year, and vegetated substrate declined at a rate of 1.6% ± 3.1% per year. Examine rates of habitat loss at 300 rookery islands below.