Deep Sea Coral and Sponge Communities
Olympic Coast National Marine Sanctuary has documented deep-sea corals, also referred to as
"cold-water corals," in the sanctuary. Unlike the better known shallow-water tropical corals,
these corals live in deep water on continental shelves, slopes, canyons, and seamounts in waters
ranging from 50 m to over 2,000 m in depth. Deep-sea corals lack symbiotic algae (zooxanthellae)
of most shallow reef building tropical corals. So, unlike their shallow water relatives that rely
heavily on photosynthesis to produce food, deep-sea corals take in plankton and organic matter for
their energy needs. Many deep-sea corals are also extremely long-lived and slow growing animals,
which make them particularly vulnerable to physical disturbance.
Despite scientific advances in the understanding of deep-sea corals, there is still very little
known about their growth rates, reproductive cycles, their functional role as habitat for marine
species, and their effects on biodiversity. We know that corals and sponges found in the sanctuary
act as biogenic structures (created by living organisms) serving a variety of functions for
deep-sea invertebrates and fish which can include:
1) a foraging platform for some
organisms, allowing them access to currents higher in the water column; 2) refuge for protection
from predators; 3) a source of food; 4) an anchor for egg attachment; and 5) perhaps a nursery area
for some species of invertebrates and fishes. Learning the critical functions of these species is
changing our view of the undersea world and the importance of these ecosystems.
Deep-sea corals and sponges may be especially vulnerable to natural or human disturbance such as
bottom trawling, mineral extraction, and cable trenching - activities that result in physical
disruption of the seafloor. Such disturbances could require very long recovery periods.
The advancement of new underwater survey technology has increased our scientific knowledge and
provided new opportunities to document more of these resources. For this reason, the sanctuary is
always looking for research partnerships to leverage and supplement vital resources
to fulfill management goals.
Since many deep-sea corals and sponges in Olympic Coast National Marine Sanctuary are biogenic
habitats, they have direct relationships to the Pacific Fishery Management Council's groundfish
Essential Fish Habitat process. And with the reauthorization of the
Magnuson-Stevens Act, the regional fishery councils are given discretionary authority
to protect deep-sea corals in their own right.
The Council recently released a lengthy comprehensive report on groundfish Essential Fish Habitat
(EFH) along the west coast (Washington, Oregon and California). OCNMS has been involved in this
five year review process as a member of the Pacific Fishery Management Council's (PFMC) groundfish
EFH Review Committee. This Phase 1 report summarizes the results of the review of information that
is new or newly-available since the last Groundfish EFH Review was concluded in 2006.
The report includes:
- A description of the general requirements and elements of EFH;
- a summary of existing descriptions of EFH for Pacific Coast groundfish;
- updated maps of seafloor habitat types and bathymetry;
- current information on the distribution of Pacific Coast groundfish;
- a summary of models to predict groundfish distribution relative to habitat types, as well as trophic and ecosystem models useful for groundfish EFH;
- summaries of new information on the life history and habitat requirements of 91 groundfish species;
- updated information on threats to groundfish EFH and prey species, both from fishing and non-fishing activities;
- identification of research needs to further refine groundfish EFH.
As part of this effort, the sanctuary program has focused on surveying for sensitive biogenic
habitats, including deep-sea coral and sponge communities. Sanctuary-sponsored ROV surveys since
2004 have been contributing video data to this process as well as to the
NOAA Deep-Sea Coral Program
which partially funded many of the research survey efforts. This and other sources of new information
will be evaluated to determine if they warrant new or additional protection measures as authorized
by the Magnuson-Stevens Fishery Conservation and Management Act. Additionally side-scan sonar and
multibeam bathymetry surveys by OCNMS have been providing new seafloor maps and characterizations
that also contribute to this evaluation process.
View additional background of OCNMS mapping efforts
The Phase I report is huge (83MB) but can be downloaded in sections via the
Full resolution maps and databases from this report are publicly available at the
PaCOOS web site
Please check out our link for more information about the
tools, data collection and analysis
we use during our research surveys. We are also providing you with a link to
Deep Coral & Sponge Projects
with related data, reports, and products.
Contact for page content: Liam Antrim