Sharks thrive in hot spots of prey
image:
Caribbean reef sharks and fish.
view moreCredit: Andy Mann
Sharks need healthy habitats, and some have a strong preference for locations jam-packed with food, according to FIU research.
A recent study in Animal Conservation of Caribbean reef sharks in the Bahamas, where shark fishing has been banned for years, shows the sharks don’t seem to like places where prey are hard to find. Instead, they prefer to live where prey is most abundant, but just having a lot of prey is not enough, according to Alastair Harborne, associate professor of biological sciences and lead author of the study. The sharks appear to like a lot of prey that are densely populated in small reef areas — maybe meaning less work for a tasty meal. In addition to making mealtimes more efficient, hunting in these more strategic spots could help sharks access other habitats and from not becoming food themselves, the researchers said. Bigger shark species may tend to hang out in larger reef areas with abundant prey and Caribbean reef sharks likely want to avoid those bigger sharks.
With these findings, the researchers say food abundance should be a consideration for conservation in conjunction with fishing bans.
“We know that large predators, like sharks, are threatened by hunting and fishing, but know less about whether we should also be thinking about protecting their prey for effective conservation” Harborne said. “This study shows that prey abundance is an important factor linked to the presence of Caribbean reef sharks and that we need to take a more holistic approach to shark conservation — overfishing can affect shark populations both directly and indirectly. This work further underscores how reef health, particularly maintaining a complex structure that prey fish love to hide in, is important both for sustainable fisheries and providing sharks with enough food.”
With the use of 631 underwater cameras, researchers tracked where the sharks showed up and measured how much prey fish was available in different areas. The researchers then built statistical models to see if sharks would show up more often in places that had more prey or if other factors were more important. The findings also indicated that sharks are creatures of habit and were found most often near steep reef walls and on deeper reefs, which matches their known behavior.
This finding is important because although the banning of shark fishing is vital to their survival, it is not enough on its own. Having enough prey for the sharks to feast on is also essential. If the sole focus is stopping the capture of sharks, populations can still remain low if the protected sharks don’t have an accessible buffet of prey. So, when it comes to sharks, prey conservation helps advance shark conservation.
Journal
Animal Conservation
Method of Research
Computational simulation/modeling
Subject of Research
Animals
Article Title
The Need to Manage Prey Fish Biomass to Support Shark Conservation
No comments:
Post a Comment