ROCK LOBSTERS

HABITAT

ANATOMY

LIFE CYCLE

DISTRIBUTION

The Red Rock Lobster and Its Natural Habitat

Lobsters are strictly marine. They all have the same basic body plan (head, tail, 2 pairs of

antennae, no less than 6 pairs of mouthpart appendages and 5 pairs of legs.

‘Crayfish’ or ‘Cray’ are strictly freshwater and are clawed, i.e., New Zealand’s Koura. Unfortunately ‘Cray’ is a common term used for New Zealand’s marine lobsters. Koura is the general Maori name for both (freshwater) crayfish and (marine) lobsters.

 

New Zealand has four species of rock lobsters (spiny lobsters), the most common of which is the Red Rock Lobster (J asus edwardsii). In Australia this species is known as the ‘Southern

Rock Lobster’.

 

The other species found in New Zealand are the:

 

  1. Packhorse Rock Lobster /Green Rock Lobster. (S agmariasus verreauxi). This lobster is less than 1% of commercial rock lobster landings. It is the world’s largest rock lobster.
  2. Deep-water Rock Lobster (Projasus parkeri) is taken occasionally as incidental catch from trawling but is not marketed.
  3. a tropical rock lobster species (Panulirus sp.) found only at the Kermadec Islands.

 

The Red Rock Lobster is dark red and orange above, paler and yellowish below. The body is spiny, especially on the head. They can weigh up to 8 kg and reach lengths of about 60 cm (excluding the feelers).

The Red Rock Lobster

Packhorse Lobster

In contrast the Packhorse lobster is green; has a distinctive ‘carapace’ (the protective shell of the head and thorax). The Packhorse’s carapace has a distinctive shape at the front part and distinctive patterns of spines. The Packhorse also has a lack of sculpting on its tail. As the world’s largest rock lobster it has been found to weigh up to 20 kg and reach lengths of 70 cm.

 

The deepwater rock lobster has a distinctive apricot colour, two prominent rows of spines on its carapace and a central ridge along the top of its tail. It is a much smaller rock lobster reaching lengths of 25 cm.

 

The tropical rock lobster species is a medium sized species of the western pacific. They have a distinctive structure at the base of each feeler that produces a sharp, rasping sound when the feelers move.

Habitat

Very small lobsters usually shelter alone in small cracks or holes.  As they grow they become more gregarious and can be found in groups of 50 or more.  This behaviour helps to protect them from predators.  Once they become sexually mature their willingness to share dens varies seasonally especially for males (see section on reproduction).

 

During the day Red Rock Lobsters are normally found in rock crevices (dens), which provide shelter from predators, storms, and the sun.  They generally leave the dens around dusk to forage for prey, returning just before dawn.

 

The deep-water rock lobster is a very deep-water lobster, found between 500 m and at least 900 m.  Our knowledge of its deep rocky habitats is very limited.

 

 

 

 

Distribution

The red rock lobster is found throughout New Zealand, on seamounts in the Tasman Sea and around southern Australia.  In New Zealand they are found from the Three Kings Islands in the north all the way to the Auckland Islands in the south and to the Chatham Islands in the east.  They are also found on shallower seamounts to about 300 m depth throughout New Zealand’s Exclusive Economic Zone.  The red rock lobsters found at the Auckland Islands are the southernmost rock lobsters in the world.

 

Packhorse rock lobsters are widely distributed, as far north as the Kermadec Islands, south to Foveaux Strait, and east to the Chatham Islands.  They are fished mainly in the far north of NZ. (They also occur in eastern Australia – northern Victoria and New South Wales - where they are commonly called the Eastern Rock Lobster).

 

The deep-water rock lobster is widespread in the southern oceans.  The species is most commonly found in the Bay of Plenty, off the Wairarapa coast and across the Chatham Rise.

© NZ Rock Lobster Industry Council Ltd