User:Abigra/Primnoa

Description
The Primnoa Genus are members of the Primnoidae family. They are soft corals, and benthic organisms which prefer to grow in cold, nutrient rich waters. They are slow growing in the deep waters, and have vital ecological interactions with its environment and the megafauna that also inhabit the region.

Ecology
Various species seek shelter and protection from the Primnoa genus. These include species of crabs, shrimps, and six different identified species of rockfish. Shrimp are observed to be hiding among the polyps of the corals, while crabs were found beneath them. Rockfish were found both beneath and among the polyps. In some circumstances, species were found to be using the protection of the coral polyps for reproductive purposes, as they were well hidden from predators among the coral’s branches.

Additionally, some species of suspension feeders use the branches to obtain nutrients. These species include various crinoids, basket stars, anemones, and sponges, which utilize the branches of the corals to elevate their position in the water, and collect floating particles in the water column. The suspension feeders have been reported in association with Primnoa at depths greater than 300 m.

Predators of the Primnoa include sea stars, nudibranchs, and snails, though sea stars are the primary coralivors for the family. One study found that sea stars were responsible for 34-45% of the consumption of the soft coral polyps.

Conservation
The largest risk for this family of corals comes from fisheries and net trawling, which uproots the corals and destroys them. Sometimes, the corals can be seen to be worn as jewelry by natives, as they are a bycatch of the fishing hawks and not useful for other purposes. Nearly 39% of the seafloor of the Aleutian Islands shows disturbance due to bottom-contact fishing tool and gear such as nets. Because of their vital interactions with megafauna in these ecosystems, fisheries must integrate coral conservation into their practices, or otherwise risk disturbance to their entire industry.

The Aleutian Islands
The Aleutian Islands are an island chain off the coast of Alaska, in the North Pacific. They range approximately 6,821 square miles, and are made up of around 300 islands, including 14 larger volcanic islands. The waters are cold and nutrient rich due to the active margins they inhabit, and experience large amounts of upwelling from the seafloor.

The benthic environments that P. wingi are found provide the capacity for unique and highly diverse sponges and soft corals. In turn, these organisms provide the basis for a habitat to many vertebrate species such as fish. This region is home to the most productive fisheries of the Northern Pacfic due to the benthic abundance and its capacity to support vertebrate species. In general, corals are most abundant at depths between 100 and 200 m, but can be found anywhere from 27 to 363 m down.

19 species of corals known in the Aleutian Islands belong to the Primnoidae family, and 25 of the 69 documented species of corals in the Aleutian Isles, including P. wingi are endemic species. Meaning they are restricted to the geographical range that spans the Aleutian Islands; however this diversity begins to increase west of 169°W. It is believed by some that the Aleutian Islands serve as the evolutionary cradle for some taxa of cold water soft corals, due to the sheer diversity and abundance of the organisms that the waters display.