Data for: Do greater coral cover and morphological diversity increase habitat complexity?

Description: This dataset contains model output from Coralcraft, a 3D mechanistic simulation model of coral community growth. Each zipped folder is the output of model simulations for a coral community type, where the 'world' of each simulation was saved every 13 time step and the simulation replicated 100 times. The folders are named in the following format: [community type id]_[coral community type]_[no. of timesteps]_tss_[no. of runs]_run. e.g. 1_max.div_260_tss_100_run

Aim of project: To assess how the coral cover, morphological composition and diversity of living coral communities affects habitat complexity at a localised reef scale using a three-dimensional coral model.

Methods: We used Coralcraft to investigate structural complexity and shelter provision in different coral communities. We developed new metrics of shelter to capture the mechanisms by which structure is likely important to reef species, accounting for factors such as the size of predator and prey and different hunting strategies. We simulated the growth of 13 coral community types with varying compositions of 10 common coral morphologies, calculating coral cover and 10 habitat complexity metrics (six novel and four well-established) over a five-year period. 

Results: We found that more diverse coral communities did not always have the greatest structural complexity and shelter, in part due to certain morphologies having disproportionate influence on the resulting habitat complexity. Communities with lower structural complexity did not necessarily provide less shelter. The relationship between coral cover and habitat complexity metrics varied widely between different communities and was often nonlinear.

Main conclusions: We conclude that accounting for the morphological composition of coral communities can vastly improve the ability to predict or infer habitat complexity—both structural complexity and shelter provision—from measures of coral cover.

See link to Github for code for model simulation and metric calculation.