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Local conservation actions, like rounding up predatory snails, can significantly boost the resilience of corals to climate-induced bleaching, according to a new study. To test whether local actions can make a difference, a research team focused on one threat to reefs that is often controlled by local managers -- populations of coral-eating animals like snails and starfish that have become too abundant. At high densities, these coral-eating animals, or "orallivores," can cause low-grade but chronic stress to corals. Some of them are like Dracula, constantly sucking the energetic reserves out of corals and leaving them less equipped to deal with harsh environmental conditions such as extreme warm temperatures and bleaching. To get a global sense of how managers deal with this threat, the researchers surveyed more than 30 coral reef management agencies worldwide, finding that many agencies reduce local corallivore populations in their sites. The researchers then mimicked managers by manually removing a voracious and common coral-eating snail from corals in the Florida Keys during a three-month spike in ocean temperatures in 2014. That warmup caused widespread coral bleaching across much of the eastern Caribbean and Gulf of Mexico. The researchers focused their efforts on brain corals, which were found in a survey of six corals reefs in the Florida Keys to be particularly susceptible to predation by the snail.