skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

Explore Research Products in the PAR
It may take a few hours for recently added research products to appear in PAR search results.


  • NSF Public Access
  • Search Results
  • Plasticity of Porites astreoides Early Life History Stages Suggests Mesophotic Coral Ecosystems Act as Refugia in Bermuda
Title: Plasticity of Porites astreoides Early Life History Stages Suggests Mesophotic Coral Ecosystems Act as Refugia in Bermuda
As the devastating impacts of global climate change and local anthropogenic stressors on shallow-water coral reefs are expected to rise, mesophotic coral ecosystems have increasingly been regarded as potential lifeboats for coral survival, providing a source of propagules to replenish shallower reefs. Yet, there is still limited knowledge of the capacity for coral larvae to adjust to light intensities that change with depth. This study elucidates the mechanisms underlying plasticity during early life stages of the coral Porites astreoides that enable survival across broad depth gradients. We examined physiological and morphological variations in larvae from shallow (8–10 m) and mesophotic (45 m) reefs in Bermuda, and evaluated differences in survival, settlement patterns and size among recruits depending on light conditions using a reciprocal ex situ transplantation experiment. Larvae released from mesophotic adults were found to have significantly lower respiration rates and were significantly larger than those derived from shallow adults, indicating higher content of energetic resources and suggesting a greater dispersal potential for mesophotic larvae compared to their shallow counterparts. Additionally, larvae released from mesophotic adults experienced higher settlement success and larger initial spat size compared to larvae from shallow adults, demonstrating a potential connection between parental origin, offspring quality, and recruitment success. Although both shallow and mesophotic larvae exhibited the capacity to survive and settle under reciprocal light conditions, all larvae had higher survival under mesophotic light conditions regardless of parental origin, suggesting that conditions experienced under low light may enable longer larval life, further extending the dispersal period. These results indicate that larvae from mesophotic Porites astreoides colonies are likely capable of reseeding shallow reefs in Bermuda, thereby supporting the Deep Reef Refugia Hypothesis.  more » « less
Award ID(s):
1937770
PAR ID:
10326602
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Frontiers in Marine Science
Volume:
8
ISSN:
2296-7745
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. ; ; ; ; ; (, Royal Society Open Science)
    The_Royal_Society_Publishing (Ed.)
    Coral reefs, hubs of global biodiversity, are among the world’s most imperilled habitats. Healthy coral reefs are characterized by distinctive soundscapes; these environments are rich with sounds produced by fishes and marine invertebrates. Emerging evidence suggests these sounds can be used as orientation and settlement cues for larvae of reef animals. On degraded reefs, these cues may be reduced or absent, impeding the success of larval settlement, which is an essential process for the maintenance and replenishment of reef populations. Here, in a field-based study, we evaluated the effects of enriching the soundscape of a degraded coral reef to increase coral settlement rates.Porites astreoideslarvae were exposed to reef sounds using a custom solar-powered acoustic playback system.Porites astreoidessettled at significantly higher rates at the acoustically enriched sites, averaging 1.7 times (up to maximum of seven times) more settlement compared with control reef sites without acoustic enrichment. Settlement rates decreased with distance from the speaker but remained higher than control levels at least 30 m from the sound source. These results reveal that acoustic enrichment can facilitate coral larval settlement at reasonable distances, offering a promising new method for scientists, managers and restoration practitioners to rebuild coral reefs. 
    more » « less
  2. ; ; ; ; (, Frontiers in Marine Science)
    The settlement of coral larvae is an important process which contributes to the success and longevity of coral reefs. Coral larvae often recruit to benthic structures covered with crustose coralline algae (CCA) which produce cues that promote settlement and metamorphosis. The PeysonneliaceaeRamicrustaspp. are red-brown encrusting alga that have recently become abundant on shallow Caribbean reefs, replacing CCA habitat, overgrowing corals and potentially threatening coral recruitment. In order to assess the threat ofRamicrustato coral recruitment, we compared the survival and settlement ofPorites astreoidesandFavia fragumlarvae to 0.5 – 2 mg ml-1solutions ofRamicrustasp. or CCA as well as sterile seawater (control). In all cases larval mortality was extremely high in theRamicrustatreatments compared to the CCA and control treatments. We found 96% (± 8.9% standard deviation, SD) mortality ofP. astreoideslarvae when exposed to solutions ofRamicrustaand 0 - 4% (± 0 - 8.9% SD) mortality in the CCA treatments. We observed 100%F. fragumlarval mortality when exposed toRamicrustaand 5 – 10% (± 10 – 20% SD) mortality in the CCA treatments. Settlement or surface interaction of larvae in the CCA treatments was 40 - 68% (± 22 - 37% SD) forP. astreoidesand 65 - 75% (± 10 - 19% SD) forF. fragum. TwoP. astreoideslarva that survivedRamicrustaexposure did settle/surface interact, suggesting that some larvae may be tolerant toRamicrusta. These results suggest thatRamicrustais a lethal threat to Caribbean coral recruitment. 
    more » « less
  3. ; ; ; (, Ecology)
    Abstract The abundance of many Caribbean corals has declined over the past few decades, yet nowPorites astreoidesis more common on many shallow reefs than in the 1980s and shows evidence of local adaptation. We compare the small‐scale (1–8000 m) genetic structure of this brooding species and the broadcasting coralOrbicella annularison reefs (<14 m depth) in St. John, US Virgin Islands, to examine how larval dispersal and asexual propagation contribute to the retention of genotypes within reefs. Populations ofP. astreoideshave genetic structure across reefs separated by a few 100 m, increased relatedness within reefs, and parthenogenetic larval propagation confirmed by parent–offspring genotyping. Within reefs,P. astreoidescolonies <1 m apart are more related, independent of clonal reproduction, than corals at greater distances. In contrast,O. annularislacks across‐reef genetic structure, has low relatedness within and among reefs, and does not produce asexual larvae. Small‐scale genetic structure and high relatedness inP. astreoidesare evident even without considering asexual propagation, but asexual reproduction enhances these differences. Neither species shows the genetic signature of inbreeding or reduced genotypic diversity despite the high within‐site relatedness ofP. astreoides. Monitoring on these reefs from 1987 indicates thatPoriteshas increased in abundance whileOrbicellahas decreased in abundance. The success ofPoritesis due to greatly increased settlement and recruitment compared withOrbicella. Together these results indicate that high numbers of locally retained and successful genotypes might explain the relative success ofPoriteson shallow, present‐day reefs in the Caribbean. 
    more » « less
  4. ; ; ; ; (, Ecosphere)
    Abstract The ecological distribution of coral species from shallow to mesophotic reefs is dependent on light, which varies drastically among local environments. Current definitions of mesophotic coral ecosystems primarily rely on a 30‐m recreational SCUBA boundary to define the upper limits of the community; however, this boundary does not consider local conditions and physiological adaptions of coral species. Using in situ benthic imagery and chlorophyll fluorescence measurements, we examined species distribution and community similarity, as well as photoacclimatization of two common depth‐generalist species (Montastraea cavernosaandPorites astreoides) across shallow to mesophotic reef zones at Little Cayman Island. Photoquadrat image analysis revealed a significant shift in coral species assemblages between 25 and 35 m, which was accompanied by a 30% drop in available surface light, suggesting light is a key driver of coral community composition. Patterns of photoacclimatization across depths differed significantly between the two coral species, with available surface light and the quantum yield of photochemistry in photosystem II found to be significant determinants of each species' abundance. These results provide valuable baseline data on coral community composition across a broad depth gradient in Little Cayman that can contribute to a growing body of evidence to set an upper boundary of mesophotic reefs based on light availability and photoacclimatization potential of depth‐generalist species. 
    more » « less
  5. ; ; (, Annual Review of Ecology, Evolution, and Systematics)
    Mesophotic coral reefs, currently defined as deep reefs between 30 and 150 m, are linked physically and biologically to their shallow water counterparts, have the potential to be refuges for shallow coral reef taxa such as coral and sponges, and might be a source of larvae that could contribute to the resiliency of shallow water reefs. Mesophotic coral reefs are found worldwide, but most are undescribed and understudied. Here, we review our current knowledge of mesophotic coral reefs and their functional ecology as it relates to their geomorphology, changes in the abiotic environment along depth gradients, trophic ecology, their reproduction, and their connectivity to shallow depths. Understanding the ecology of mesophotic coral reefs, and the connectivity between them and their shallow water counterparts, is now a primary focus for many reef studies as the worldwide degradation of shallow coral reefs, and the ecosystem services they provide, continues unabated. 
    more » « less
  • Citation Formats
  • MLA
  • APA
  • Chicago
  • BibTeX
  • Save / Share this Record
  • Send to Email