MCR LTER: Coral Reef: Density-dependence data for Edmunds, et al., Ecology 2018

This dataset contains coral cover data describing the context within which denisty-dependence (DD) was measured on the island of Moorea, French Polynesia, including
data describing the benthic community, diameters of Pocillopora spp. measured in photoquadrats, surveys of corals and recruits.

These data correspond to figures 1 through 3 in the manuscript by PJ Edmunds, L. Bramanti, and H.R. Nelson,
'Density-dependence mediates coral community structure', Ecology, 2018. The reefs of Mo’orea, French Polynesia,
provide the opportunity to study DD of coral population growth, because coral assemblages in
this location responded to declines in abundance with high recruitment and an increase in cover
during which recruitment of pocilloporid corals was inversely associated with density. This study
tests for DD in this system, first, by describing the context within which it operates: coral cover
changed from 46% in 2005, to less than 1% in 2010 following an outbreak of a corallivorous sea star
and a cyclone, and then increased to 74% by 2017, in large part through inverse density-
associated pocilloporid recruitment. Second, a test for DD of recruitment was conducted by
decreasing Pocillopora spp. cover from 33% to 19%: one year later, the density of Pocillopora
spp. recruits was 1.65-fold higher in the low versus high cover treatment. Finally, the effects of
DD were investigated by comparing simulated and empirical distributions of pocilloporid
colonies: as predicted by DD, small colonies were randomly distributed, while large colonies
were uniformly distributed. Together these results demonstrate DD of population regulation for
Pocillopora spp. corals, thus revealing the potential importance of this ecological principle in
determining the resilience of coral assemblages.