Information briefs and risk analyses for species under consideration ...

Table 1: Octopus in New Zealand
Order Family
Endemic
species
Total
species
Octopoda Amphitretidae 0 2
Argonautidae 0 2
Bolitaenidae 0 3
Cirroteuthididae 2 2
Grimpoteuthididae 1 1
Luteuthididae 1 1
Octopodidae 15 22
Ocythoidae 0 1
Opisthoteuthididae 4 5
Tremoctopodidae 1 1
Vitreledonellidae 0 1
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Biology
Overview
6 Octopus refers to the Genus Octopi, which are members of the Phylum Mollusca, of
the class Cephalopoda, order and family Octopoda. The majority of octopuses are
characterised by soft bodies, eight arms, well-developed eyes, and complex life cycles
and behaviours.
7 Most octopuses have a globe-shaped ‘head’ that contains all the vital organs and
mouth. The mouth has a sharp beak that is used to kill prey. Octopus skin is relatively
smooth and many species are able to change colours by contracting skin cells filled
with pigments to allow them to hide when hunting for prey. Some octopuses can even
mimic other fish and objects, and their defensive arsenal includes the ability to squirt
an ink-like substance at an attacker to mask their getaway.
Growth, Reproduction and Recruitment
8 The life cycle of many octopuses involves a short lifespan (typically 12-24 months),
fast growth, and semelparous reproduction (i.e. spawns once and dies). Species
fecundity varies widely with some producing tens of eggs (the rare deep-sea octopus,
Thaumeledone zeiss) and others hundreds of thousands of eggs (Pinnoctopus
cordiformis 56,000-232,000 eggs). A number of octopuses are known to brood young
(less than a year old).
Spatial and temporal distribution and key areas (feeding, spawning,
migration)
9 The lack of quantitative information on the life history, growth, and distribution of
octopus makes it extremely hard to estimate distribution patterns.
10 Work done by NIWA has produced some charts showing the annual distribution of
certain umbrella octopus species. However, the information used to generate these
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