Prevalence and extent of coral diseases in shallow and mesophotic reefs of the Southwestern Atlantic

Abstract

Coral reef ecology has advanced in many fields, but disease patterns across depth gradients remain unclear. By comparing the prevalence and extent of bleaching and diseases in 160 colonies of Siderastrea stellata between shallow and mesophotic reefs, we observed that prevalence was high (75%) regardless of depth, but the extent was about two times greater in mesophotic than shallow reefs (14.4% vs. 6.6% of colony area, respectively). Across the shallow reefs, where S. stellata co-occurred with Montastraea cavernosa, M. cavernosa showed lower prevalence (27% of 30 colonies) and extent (1.8% of colony area) compared to S. stellata. Besides bleaching, five coral diseases afflicted S. stellata and two affected M. cavernosa. Because diseases are spread over the entire gradient of depth, any attempt of managing the diseases should consider both shallow and deep reefs to be effective.

Physiological and morphological plasticity in Stylophora pistillata larvae from Eilat, Israel, to shallow and mesophotic light conditions

“… 5 Consequently the optimistic Deep Reef Refuge Hypothesis emerged. 6 , 7 However, deeper reefs are not universally protected from impact with recent studies documenting storm damage, 8 plastic pollution, 8 thermal bleaching, 9 , 10 and disease 11 , 12 , 13 at mesophotic depths. In addition, mesophotic corals often have lower productivity, growth rates, and reproductive output relative to shallow conspecifics.…”

Exploring depth‐related patterns of sponge diversity and abundance in marginal reefs

“…Known as “marginal reefs”, these formations occur under marginal or suboptimal conditions (Sommer, 2022 ). Despite being the focus of recent studies (Bleuel et al., 2021 ; Browne & Bauman, 2023 ; Morais & Santos, 2022 ; Sommer, 2022 ), these marginal habitats are still poorly explored, especially in the Southwestern Atlantic (Morais et al., 2018 ; Soares, 2020 ; Sommer, 2022 ). Marginal reefs are located in turbid‐zone, high‐sedimentation, high‐temperature regions, often associated with deeper zones, great nutrient concentration, high primary production rates, and extreme pH fluctuations, which can limit the distribution and occurrence of many reef species (Sexton et al., 2009 ; Soares et al., 2021 ).…”