The role of biocomplexity in the restoration of tropical hard-bottom sponge communities and their ecosystem services.
Mark Butler, Jack Butler, and Marla Valentine
The implications of lost biocomplexity are still poorly understood for most marine ecosystems. Sponges are an ecological cornerstone for tropical coral reef and hard-bottom communities where they provide essential ecosystem services such as: water column filtration, nitrogen cycling, and the provisioning of shelter for a variety of fauna, some of which are “soniferous” and contribute to acoustically unique soundscapes. However, over the past few decades hard-bottom communities in the Florida Keys have suffered massive sponge die-offs that have destroyed ecosystem complexity. Though unfortunate, those changes have created a “blank slate” on which we have been experimentally manipulating sponge community biocomplexity to test its contribution to ecosystem processes. By linking sponge restoration with field and mesocosm experiments, we have been exploring the effects of sponge biocomplexity on fish and invertebrate habitat use and recruitment, water column properties, and underwater soundscapes. Just a few years after establishment, restoration sites with more complex sponge communities exhibit high rates of sponge recruitment, attract a great diversity of motile species, and produce underwater soundscapes similar to those of undisturbed natural sites. Mesocosm studies demonstrate that sponge biodiversity influences water column properties, a result that we are testing in an in situ experiment. Collectively, this diverse set of studies demonstrates that the biodiversity of sponge communities is consequential to ecosystem services and that sponge community restoration that heeds this message can be effective.
Department of Biological Sciences, Old Dominion University, Norfolk, VA 23529 [email protected]
Mark Butler, Jack Butler, and Marla Valentine
The implications of lost biocomplexity are still poorly understood for most marine ecosystems. Sponges are an ecological cornerstone for tropical coral reef and hard-bottom communities where they provide essential ecosystem services such as: water column filtration, nitrogen cycling, and the provisioning of shelter for a variety of fauna, some of which are “soniferous” and contribute to acoustically unique soundscapes. However, over the past few decades hard-bottom communities in the Florida Keys have suffered massive sponge die-offs that have destroyed ecosystem complexity. Though unfortunate, those changes have created a “blank slate” on which we have been experimentally manipulating sponge community biocomplexity to test its contribution to ecosystem processes. By linking sponge restoration with field and mesocosm experiments, we have been exploring the effects of sponge biocomplexity on fish and invertebrate habitat use and recruitment, water column properties, and underwater soundscapes. Just a few years after establishment, restoration sites with more complex sponge communities exhibit high rates of sponge recruitment, attract a great diversity of motile species, and produce underwater soundscapes similar to those of undisturbed natural sites. Mesocosm studies demonstrate that sponge biodiversity influences water column properties, a result that we are testing in an in situ experiment. Collectively, this diverse set of studies demonstrates that the biodiversity of sponge communities is consequential to ecosystem services and that sponge community restoration that heeds this message can be effective.
Department of Biological Sciences, Old Dominion University, Norfolk, VA 23529 [email protected]