Mortality, recovery, and community shifts of scleractinian corals in Puerto Rico one decade after the 2005 regional bleaching event

Abstract

This work analyzes the mortality, recovery, and shifts in the composition of scleractinian corals from Puerto Rico one decade after the 2005 regional coral bleaching event. Temporal and spatial patterns of coral community structure were examined using a stratified, non-random sampling approach based on five permanent transects per reef at 16 reef stations. A negative correlation between percent coral cover loss and light attenuation coefficient (Kd490) was observed, suggesting that light attenuation, as influenced by water turbidity and depth, played a major role in coral protection during the bleaching event (“sunblock effect”). Responses of coral assemblages varied after the bleaching event, including shifts of cover from massive corals (Orbicella spp.) to opportunistic (Porites astreoides) and branching corals (Madracis auretenra, P. porites) and/or turf algae; partial recovery of reef substrate cover by O. annularis complex; and no measurable changes in coral assemblages before and after the event.

Quantifying the Effects of Hurricanes Irma and Maria on Coastal Water Quality in Puerto Rico using Moderate Resolution Satellite Sensors

“…When comparing the inner and outer shelf pixel values of Chl-a and K d 490, this follows the distinct neritic to oceanic gradients of water turbidity observed for the oceanic waters surrounding Puerto Rico [5]. This suggests that areas closer to shore experienced higher levels of degraded water.…”

“…As development has increased in Puerto Rico, reduced vegetation increases the likelihood of sediments, nutrients, and hazardous substances that can be eroded into coastal waters [4], especially after extreme rain events like hurricanes. Excess sediment, nutrients, and other pollutants can negatively affect seagrass and reef environments principally by decreasing light availability and thereby reducing the photosynthetic capacity for growth [4,5]. Benthic organisms, especially sessile animals, are at particular risk due to poor water quality caused by hurricanes [6].…”

Water Quality Anomalies following the 2017 Hurricanes in Southwestern Puerto Rico: Absorption of Colored Detrital and Dissolved Material

“…These factors have been historically monitored for water quality assessment and referenced as indicators of coastal and marine ecosystem health [4,7,8]. Chlorophyll (a proxy for phytoplankton abundance) [9] and turbidity (as well as CDOM) contribute to reducing light penetration in the water column [4,5], which has been associated with ecosystem changes, phytoplankton dynamics [9], and growth and distribution of seagrasses [4] and coral reef species [10]. These effects on light penetration and quality can be considered environmental stressors and a water pollutant [11].…”

“…LPNR, in southwestern Puerto Rico, was designated to protect fragile tropical marine ecosystems, particularly coral reefs, which are experiencing accelerated degradation and mortality in this and many parts of the world [21]. We have witnessed unprecedented disappearance of coral cover due to coral diseases, bleaching and thermal stress, runoff, anthropogenic uses, and hurricanes [10,22,23]. La Parguera has one of the largest coral reef systems in Puerto Rico, with 10-14 coral species in 100 m 2 located at a diverse bottom type; presenting one of the most diverse benthic habitats on the island, combining coral reefs, seagrasses, mangroves, sandy bottoms, among others [23].…”

“…LPNR supports a blue economy around the region with local fisheries, tourism, and recreation. Coral reefs reach their maximum development under oligotrophic conditions but can exist over a wide range of water types under variable coastal influences [10,24]. In coastal waters, light penetration can be subject to sudden changes when specific weather conditions occur.…”