Coral Reef and Seagrass Ecosystems
U.S. coral reef ecosystems cover less than one percent of the earth’s surface, yet
are among the most diverse and productive communities on Earth. They enhance biological
diversity, fisheries, tourism, maritime and cultural heritage, and protect shorelines
from storm damage. Stressed by human activities and extreme events, coral reefs
are in decline worldwide. Excess nutrients and sediments, overfishing, coastal development,
and increased coral bleaching threaten nearly 60 percent of the world’s reefs and
the resources they support.
Seagrasses are also in decline world-wide, unable to withstand the cumulative toll
of nutrient and sediment runoff, invasive species, disease, commercial fishing and
aquaculture practices, and climate change. Ship groundings and prop scars are
also problem. Seagrasses stabilize sediments, alter water flow and nutrient cycling,
and provide habitat for fish and invertebrates.
NCCOS is working
to understand these problems and evaluate possible solutions. We assess, map, and
monitor coral reef ecosystems throughout the U.S. and the Freely Associated States.
We led the development of the first national State of the Reefs
reports and are key players in mapping U.S. shallow-water
coral reef systems. With the release of the National Summary of NOAA's Shallow-water Benthic Habitat Mapping
of U.S. Coral Reef Ecosystems,
NCCOS and its partners have mapped nearly 3 million acres (or 12,100
km2) of coral reef ecosystem habitats across the nation. With respect
to seagrass, we
developed many of
the techniques used in seagrass restoration and the monitoring and evaluation of
restoration projects.
We are leading an effort to characterize and understand intermediate depth,
mesophotic coral ecosystems found between 30-150 meters (100-490 feet). This
includes publishing the first Mesophotic Coral Ecosystems
Research Strategy to identify critical research
needs to help inform management of these ecosystems and a dedicated theme section
in the journal Coral Reefs
focused on the state of knowledge regarding mesophotic
coral ecosystems.
NOAA is also
interested in locating and protecting many of the nation’s deep-sea
corals. These areas support some of our most productive fisheries.
NCCOS developed
models that predict where deep corals are mostly likely to grow, helping
NOAA avoid
spending its limited resources mapping in areas where there are no reefs.