|
Mediterranean
fan worm
Sabella spallanzanii
|
|
Overview
This
pest is not yet found in New Zealand, although it is
found on the south and south-west coasts of Australia
and in Tasmania. It lives in the open seas at depths
of one to 30 metres and on rocks and other hard surfaces
in shallow harbour areas.
It
prefers sheltered areas away from wave action. The fanworm
grows quickly and can form dense beds. It displaces
other species and grows on boats and other marine structures.
This species could be a threat to our marine ecosystem
and could cause problems for marine farmers and boat
owners.
|
How
could it get here?
Adult
fanworms could travel to New Zealand on the outside
of a boat's hull or in the containers that carry the
boat's equipment and fish. Young fanworms could be carried
here in a ship's ballast water.
|
|
Description
Size:
Tube length 90-400 mm, crown radioles 9-64 mm long.
Shape: Tube-shaped body, two groups of radioles - one
spiral, the other forming a semicircle.
Construction:
The outer layer of tube is made of silt or mud and often
has organisms growing on it.
|
|
Key
features
Only
one of the two groups of radioles making up the crown
has a spiral shape. The radioles are webbed for the
first 5 mm. Turned-down flaps are often orange in colour
and the first ventral shield is the widest.
For
more information, see:
Mediterranean
fanworm action plan September 2001 (PDF 350KB) -
Link to NZ Biodiversity web site.
|
 |
 |
| |
top
|
|
European
shore
(or green) crab
Carcinus maenas
|
|
Overview
If
this crab enters New Zealand, it could reduce the number
of different organisms we see in our marine environment
and have a serious impact on our scallop and mussel
industries. The European shore crab adapts very well
to new places. It is found in sheltered rocky shores,
mainly under large boulders between the high and low
tide marks or buried in the sand on sheltered rocky
foreshores. It eats other crabs, clams, limpets, barnacles,
mussels, and even young scallops.
|
How
could it get here?
The
European shore crab could travel to New Zealand in a
ship's containers for carrying equipment and fish, in
ballast water, or on fishing equipment.
|
|
Description
Size:
Up to 8 cm across the body though more commonly 5-6
cm.
Shape:
The body is broad at the front with a narrower but blunt
rear forming a triangular shape.
Colour:
The young crabs vary in colour but are usually olive
green, while the upper surface of the adult crabs is
distinctly dark green. The adults also often have yellow/orange
patches.
|
|
Key
features
The
shore crabs have 10 well-developed spines on the front
edge of the body, five on either side of the rostrum.
The broad triangular body shape and the absence of swimming
paddles on the last pair of legs are also notable features
of this crab. Finally, it will generally show no aggression
when handled.
For
more information, see:
European
shore crab - Link to NZ Biodiversity web site.
|