Abstract or Keywords
Many coral reefs have been degraded over the past several decades due to the
combination of human and natural disturbances. In the Florida Keys, coral habitats have been in
decline since the 1970s due to multiple stressors including coral bleaching, disease outbreaks,
hurricanes, and cold snaps. As a result, once coral-dominated communities are now becoming
increasingly dominated by macroalgae, which are associated with lower economic, ecological,
and aesthetic value. Herbivory, or the grazing of macroalgae, is a key process on coral reefs that
helps maintain coral-dominated states and can potentially reverse macroalgal shifts on degraded
reefs. The Caribbean king crab is a noted voracious algae consumer with natural physiological
resilience to stressful environmental conditions, making them a promising coral restoration
candidate. Therefore, understanding the environmental factors which promote or discourage
settlement may serve as a management tool for local restoration efforts. In this experiment,
larvae were exposed to five different treatment cues that include: a) control (no cue, purified
seawater), b) chemically defended algae cue seawater (Dictoyata spp.), c) conspecific cue
seawater (Mithrax spinosissimus), and d) spiny lobster predator cue seawater (Panulirus
guttatus). Caribbean king crab larvae were more likely to metamorphose and settle when
exposed to the control and conspecific cues, whereas there was a higher mortality rate and lower
settlement among larvae that experienced predator odors and the algae cue seawater.