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Published on: January 11, 2015
Predator-prey role reversal in a marine benthic ecosystem
Science (New York, N.Y.)
|October 7, 1988
Summary
Two South African islands exhibit contrasting benthic communities. Predator-prey roles reversed when rock lobsters were introduced to an island with high whelk densities, suggesting ecosystem state shifts.
Area of Science:
- Marine biology
- Ecology
- South African west coast ecosystems
Background:
- Two adjacent islands display distinct benthic communities.
- Malgas Island: dominated by seaweeds and rock lobsters preying on mussels and whelks.
- Marcus Island: characterized by mussel beds, with few rock lobsters or seaweeds, but high whelk densities.
Purpose of the Study:
- Investigate the contrasting benthic communities on Malgas and Marcus Islands.
- Examine the predator-prey dynamics between rock lobsters and whelks.
- Determine if these distinct communities represent alternative stable states.
Main Methods:
- Observational study of natural benthic communities.
- Experimental manipulation involving the transfer of rock lobsters.
- Monitoring of community structure and species interactions over four years.
Main Results:
- Malgas Island: rock lobsters suppress mussel settlement and prey on whelks.
- Marcus Island: whelks dominate and prey on introduced rock lobsters, reversing typical roles.
- Both community states persisted for four years, indicating stability.
Conclusions:
- The predator-prey relationship between rock lobsters and whelks can be reversed.
- These contrasting communities may represent alternative stable states of the same ecosystem.
- Reversed predator-prey roles could be an intrinsic mechanism maintaining ecosystem states.
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