Long-term Changes in a Spatially Subsidized Insular Ecosystem in the Archipelago of Bahía de los Ángeles, Mexico

The ocean-land interface forms an important ecosystem - the coastal ecotone - that occupies 8% of the earth’s surface along an estimated 594,000 km of coastline. Large fluxes of resources (spatial subsidies) link habitats across this ecotone, often with dramatic consequences for the recipient systems. The archipelago of Bahía de los Ángeles, Mexico, is an example of an extremely low-productivity terrestrial habitat, receiving on average only 59 mm of rainfall a year. These islands are surrounded by a highly productive marine system, where spatial subsidies from the ocean can account for as much as 22 times in-situ terrestrial production. Understanding the mechanisms and extent of ecosystem connectivity is critical for predicting future change of coastal systems not only in Baja California, but worldwide. Pitfall traps and vegetation transects were used to create an extensive dataset of flora and fauna spanning almost 30 years on all 17 islands. Analysis of the past ten years has shown that terrestrial communities on this archipelago are responding at a variety of temporal scales to rainfall events, due to the interaction between precipitation and spatial subsidies. This research will continue to enhance international scientific partnership through a broad network of public and private collaboration in Baja California, with data going directly to land managers of this protected archipelago, and has the potential to provide new insights into the generalizability of my findings from this study.