''Cirroctopus hochbergi'' (common name: Four-blotched umbrella octopus) is a cirrate octopus living between 800 and 1,070 meters deep off the coast of New Zealand. The species is known from 48 specimens. It is most similar to its sister taxon, '' Cirroctopus mawsoni''; however, ''C. mawsoni's'' ventral pigmentation is lighter, and the two species have been found in very different areas (''C. mawsoni'' is only known in waters near Antarctica). This octopus lives near

cold seep A cold seep (sometimes called a cold vent) is an area of the ocean floor where seepage of fluids rich in hydrogen sulfide, methane, and other hydrocarbons occurs, often in the form of a brine pool. ''Cold'' does not mean that the temperature ...

s and

seamount A seamount is a large submarine landform that rises from the ocean floor without reaching the water surface (sea level), and thus is not an island, islet, or cliff-rock. Seamounts are typically formed from extinct volcanoes that rise abruptly a ...

s. It is theorized that it and all other cirrate octopuses live in the

demersal zone The demersal zone is the part of the sea or ocean (or deep lake) consisting of the part of the water column near to (and significantly affected by) the seabed and the benthos. The demersal zone is just above the benthic zone and forms a layer o ...

Description

The octopus has a pair of large, pale blotches under the eyes, and a matching pair of blotches where the fins meet the body. It is muscular and dark purple in colour.

Threats

While ''C. hochbergi'' is not used by humans, it is often taken as

bycatch Bycatch (or by-catch), in the fishing industry, is a fish or other marine species that is caught unintentionally while fishing for specific species or sizes of wildlife. Bycatch is either the wrong species, the wrong sex, or is undersized or juve ...

. One of the greatest threats to the species is

trawling Trawling is an industrial method of fishing that involves pulling a fishing net through the water behind one or more boats. The net used for trawling is called a trawl. This principle requires netting bags which are towed through water to catch di ...

, which damages its habitat. There are an estimated 250 to 1,000 mature individuals. ''C. hochbergi's'' population is currently decreasing, and it may be

locally extinct Local extinction, also extirpation, is the termination of a species (or other taxon) in a chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinctions. Local extinctions mark a chan ...

in areas where it once was common. Like other cirrates, it has a long lifespan and grows slowly, which could make it hard for the species to recover from declines in the population.

References

{{Taxonbar, from=Q2127299 Cephalopods of Oceania Endemic fauna of New Zealand Endemic molluscs of New Zealand Cephalopods described in 1999 Molluscs of New Zealand Molluscs of the Pacific Ocean Octopuses