Seamounts: Biodiversity and Fisheries
Seamount Invertebrates: Composition and vulnerability to fishing
Karen Stocks
University of California San DiegoAbstract
To describe the invertebrate communities found on seamounts and their vulnerability to fishing, a global review of seamount data was conducted. Using data from SeamountsOnline (http://seamounts.sdsc.edu ), data from 1771 kinds of organisms on 171 seamounts were evaluated, representing the largest global synthesis of seamount data to date. The data clearly indicate that seamount communities differ from those found in other deep-sea habitats. Filter-feeding corals, anemones, sponges, and feather stars are common on hard-bottomed seamounts, compared to the deposit-feeding species found most often in the muddy deep sea. The total abundance of life is generally high, leading to descriptions of seamounts as ‘underwater oases’. On almost every seamount that has been studied, new species have been found, leading to the conclusion that many species may be endemic to just one or a few seamounts. Extremely long-lived and slow-growing species have also been discovered on seamounts, representing some of the oldest animals known on earth. These same qualities also make seamount communities extremely vulnerable to fishing pressure. The tree-like and flower-like forms of the filter-feeders on seamounts are highly vulnerable to damage by bottom trawls, and the one existing study comparing fished and unfished seamounts indicates that trawling in that area reduced the overall biomass by a factor of seven and the species diversity by a factor of two. Endemic species, thought to be common on seamounts, are at greater risk for extinction. Also, impacts of trawling on very long-lived seamounts species may persist for centuries. Because of the fragility of these systems, and their potential importance to scientific research into ocean biodiversity, to future pharmaceutical discoveries, and to ocean communities as a whole, damage from trawling warrants serious attention.
Full text
(PDF)
Appendices 1a-1d: Data in
invertebrates collected from seamounts globally
1a. List of species from seamounts
- ordered by species
1b. List of species from seamounts
- ordered by seamount
1c. Bibliography of data sources
cited in appendices 1a and 1b
1d. Distribution maps for seamount
invertebrates given in appendices 1a and 1b