What are you most concerned about? The exchange of materials and organisms across discrete habitat boundaries is a universal phenomenon that occurs across diverse land, freshwater, and marine systems. MI affects coastal communities in many varied habitats, from the tropics, to temperate coasts, to boreal and sub- polar habitats [see (1, 3) and references therein]. Most obviously and directly, seabird guano, macrophytes and marine animal carcasses subsidize these land communities and allow higher numbers of consumers throughout the web. Subsidized consumers then interact with their prey and predators to indirectly affect virtually all species in coastal systems. While the changes to these subsidies are more easily recognized where there is a high productivity habitat adjacent to a low productivity one (as in Bahía de los Ángeles), undoubtedly these same impacts occur across all coastal ecosystems. In addition, these dynamics can be extended to other insular systems, such as protected areas influenced by the surrounding landscape (e.g., predatory birds subsidized via scavenging on agricultural or urban areas increase predation pressure on protected areas).
What are the gaps in understanding that need more research? We still have little understanding of how geomorphology alters the movement of spatial subsidy; how far inland (and for how long) subsidy effects persist; how retention and identity of shore drift alters MI effects; and how important these effects are at boundaries where there is less pronounced contrast between terrestrial and marine primary production.
THIS LONG-TERM DATASET WOULD NOT HAVE BEEN POSSIBLE WITHOUT EXTENSIVE COLLABORATION. COMISIÓN NACIONAL DE ÁREAS NATURALES PROTEGIDAS, THE LOCAL COMMUNITY, AND THE NON-PROFIT SCIENCE EDUCATION ORGANIZATION, OCEAN DISCOVERY INSTITUTE (PICTURED HERE) WERE CRITICAL TO CONTINUING THIS DATASET AFTER GARY POLIS’ DEATH IN 2000. PHOTO CREDIT: DREW TALLEY