New research published today (Apr 28) highlights the importance of predatory fishes in controlling sponge populations on Caribbean coral reefs. Sponges compete with corals for space, and certain species of sponge can grow quickly, even smother neighboring corals. These fast growing sponges are usually controlled by predation, however the new research finds that in areas where human fishing activities have removed spongivorous fishes, sponges regularly come in contact and overgrow corals.
The study presents a collaborative effort led by Dr. Joseph Pawlik from the University of North Carolina at Wilmington. Working alongside Dr. Tse-Lynn Loh (previously at UNCW, now currently at the Shedd Aquarium) and Steve McMurray (UNCW) and Jan Vicente (University of Maryland), we visited 12 countries throughout the Caribbean.
By comparing overfished and protected sites on a large geographic scale, we were able to examine community impacts of overfishing across the entire ecosystem. Our work supports the role of marine reserves in protecting fishes which in turn limit sponge overgrowth of corals.
We also noticed that algae were more abundant where fishes were also abundant, which potentially contradicts assumptions regarding the impact of fishes on algae populations. Since algae are also a fierce competitor with corals, future work should examine this relationship across the entire Caribbean region.
Check out the entire study online here: https://peerj.com/articles/901
Also some press releases and stories can be found online here: