Three‐dimensional species distribution modelling reveals the realized spatial niche for coral recruitment on contemporary Caribbean reefs

• Published in: Ecology letters Vol. 26; no. 9; pp. 1497 - 1509
• Main Authors: Martínez‐Quintana, Ángela, Lasker, Howard R., Wilson, Adam M.
• Format: Journal Article
• Language: English
• Published: England Blackwell Publishing Ltd 01.09.2023
• Subjects: 3D niche; Coexistence; Coral reefs; Corals; Critical components; Geographical distribution; Habitats; Modelling; Niche breadth; niche partitioning; octocoral; polygon mesh; scleractinian; seascape ecology; spatially explicit distribution patterns; structural complexity; structure from motion; Taxa; three‐dimensional habitat structure; structure from motion; spatially explicit distribution patterns; octocoral; 3D niche; structural complexity; niche partitioning; three-dimensional habitat structure; scleractinian; polygon mesh; seascape ecology
• ISSN: 1461-023X; 1461-0248
• DOI: 10.1111/ele.14281

The three‐dimensional structure of habitats is a critical component of species' niches driving coexistence in species‐rich ecosystems. However, its influence on structuring and partitioning recruitment niches has not been widely addressed. We developed a new method to combine species distribution modelling and structure from motion, and characterized three‐dimensional recruitment niches of two ecosystem engineers on Caribbean coral reefs, scleractinian corals and gorgonians. Fine‐scale roughness was the most important predictor of suitable habitat for both taxa, and their niches largely overlapped, primarily due to scleractinians' broader niche breadth. Crevices and holes at mm scales on calcareous rock with low coral cover were more suitable for octocorals than for scleractinian recruits, suggesting that the decline in scleractinian corals is facilitating the recruitment of octocorals on contemporary Caribbean reefs. However, the relative abundances of the taxa were independent of the amount of suitable habitat on the reef, emphasizing that niche processes alone do not predict recruitment rates. How the 3D structure of habitats influences niche partitioning of coral recruits is unknown. We combine species distribution models and photogrammetry to characterize three‐dimensional niches for the recruitment of scleractinians and octocorals in the Caribbean. Fine‐scale roughness is crucial for both taxa, but scleractinians occupy a wider niche. Octocoral recruitment may be facilitated by scleractinians cover decline. However, niche processes alone do not predict recruitment rates.