[Coral-List] Molecular Mechanisms of Coral Persistence Within Highly Urbanized Locations in the Port of Miami, Florida

[Coral Morphologic]

"Molecular Mechanisms of Coral Persistence Within Highly Urbanized
Locations in the Port of Miami, Florida"

For more than a decade, Coral Morphologic has sought to raise awareness of
Miami’s urban corals and their potential scientific value. These
surprisingly resilient corals appear to avoid bleaching and stem disease
better than their conspecifics offshore on the natural reefs. Over the past
two years we have been working with scientists at NOAA’s Atlantic
Oceanographic Meteorological Laboratory (AOML) to explain these differences
using molecular lab analysis of tissue samples collected in the field. That
work has culminated in ‘Molecular Mechanisms of Coral Persistence
Within Highly Urbanized Locations in the Port of Miami, Florida‘  (Rubin et
al. 2021) published (open access) in Frontiers in Marine Science:

https://www.frontiersin.org/articles/10.3389/fmars.2021.695236/full

We found that the Symmetrical Brain Corals (*Pseudodiploria strigosa*)
living in the urban environment (specifically 0-2m deep alongside MacArthur
Causeway and Star Island in Miami) were predominantly colonized by the
thermally-tolerant zooxanthellae *Durusdinium*. This was surprising because *P.
strigosa* isn't well known to host this species of zooxanthellae across its
range in the Caribbean/Western Atlantic, making these observations here in
Miami notable.

Beyond the heat tolerant symbionts, *P. strigosa* living in the urban
environment were also found to be producing proteins and enzymes known to
identify and digest potentially pathogenic invaders. These proteins could
be a two-fold benefit to the coral since disease-causing microbes can be
digested as food before they can infect the coral. The urban marine
environments around Miami often have high concentrations of phytoplankton
and turbidity in the water, along with high bacterial concentrations that
frequently require ‘no swim’ public health advisories. The ability to
capture and extract more energy from food could potentially enhance its
health and provide sustenance during times of bleaching.

These findings from a single species of urban coral in Miami’s coastal
environment suggest further investigation is warranted in the 25+ other
Scleractinian coral species that have self-recruited to the City’s concrete
and riprap shorelines. It also demonstrates how the
human-made hydrogeologic conditions around PortMiami appear to serve as a
stress-hardening evolutionary gauntlet selecting for corals that are better
adapted for life in the Anthropocene. These are not survivors, but
pioneers.

Tune in and follow along on the Coral City Camera (www.coralcitycamera.com)
where we are currently monitoring and growing fragments of urban corals on
nursery frames. We are currently collaborating with the University of Miami
to test the resilience of staghorn coral genotypes grown by their
Rescue-a-Reef program in offshore nurseries and transplanted to this
near-shore marginal environment at PortMiami.  As always we are happy to
collaborate, so feel free to reach out with any ideas you may have where
the CCC and/or this urban coral site could benefit your research.

Cheers,
Colin Foord

Coral Morphologic
Coral City Camera