Antarctic Sea Ice--a Habitat for Extremophiles -- Thomas and Dieckmann 295 (5555): 641 -- Science
However, beneath the snow lies a unique habitat for a group of bacteria and microscopic plants and animals that are encased in an ice matrix at low temperatures and light levels, with the only liquid being pockets of concentrated brines.
Survival in these conditions requires a complex suite of physiological and metabolic adaptations, but sea-ice organisms thrive in the ice, and their prolific growth ensures they play a fundamental role in polar ecosystems.
Apart from their ecological importance, the bacterial and algae species found in sea ice have become the focus for novel biotechnology, as well as being considered proxies for possible life forms on ice-covered extraterrestrial bodies.
Sea Spiders: Pycnogonida - Habitat
They are found crawling over seaweeds as well as on sea anemones (uh-NEH-muh-nees), small sea animals with long, thin, armlike body parts called tentacles (TEN-tih-kuhls); corals, the hard skeletons of certain sea creatures; and other animal colonies, or tight groupings of animals, permanently attached to the sea bottom.
Some species are found at great depths, up to 23, 000 feet (7, 000 meters), where they live near hot water springs bubbling up from the sea floor..
.

Photo by www.victorialodging.com
U.K. Sea Habitat At Risk, Needs Protection, WWF Says
The U.K.'s marine environment requires legal protection to halt a decline in many of its species and habitats, the WWF said.
sea habitats studied by its scientists were being destroyed, the Gland, Switzerland-based conservation group said in a report.
seas has worsened' since the WWF conducted its first Marine Health Check five years ago, Jan Brown, a WWF senior marine policy officer based in Godalming, southeast England, said in an e-mailed statement.
'The government accepts that more needs to be done to better manage and protect our seas, ' the Department for Environment, Food and Rural Affairs said in an e-mailed statement.
To this end, Defra said it will introduce into the next Parliament a Marine Bill, and will publish its own 'State of the Seas' report 'in the next couple of months.' .
sea life, including 'No-Take Zones' that prohibit 'extractive activities' either seasonally or permanently.
Only the basking shark, long-snouted seahorse and pink sea fan -- a type of coral -- were sufficiently plentiful in U.K.
Most of the damage to habitats came from bottom trawling, dredging and sand and gravel extraction.
IngentaConnect Age, growth and radiometric age validation of a deep-sea, habitat...
Sustainable fisheries require (1) viable stock populations with appropriate harvest limits and (2) appropriate habitat for fish to survive, forage, seek refuge, grow and reproduce.
Some deep-water habitats, such as those formed by deep-water stands of coral, may be vulnerable to fishing disturbance.
The rate at which habitat can be restored is a critical aspect of fishery management.
The purpose of this study was to characterize growth rates for a habitat-forming deep-sea coral.
These growth rates suggest that the fishery habitat created by red tree coral is extremely vulnerable to bottom fishing activities and may take over 100 years to recover.