Environmental Engineering Reference
In-Depth Information
Table 14.1
(Con't.)
Type
Treatment
Artifi cial
habitats
Natural
habitats
Structures and/
or habitats
Acceptability and
chance of success
Heat treatment Yes
Unlikely
Wharf piles
Seafl oor
Vessels
ACCEPTABILITY
:
high
SUCCESS
:
moderate
Desiccation
Yes
N/A
Vessels
Aquaculture
equipment
Scientifi c
equipment
Buoys, ropes,
chains, tyres
ACCEPTABILITY
:
high
SUCCESS
:
high
Freshwater
Ye s
N/A
Vessels
Aquaculture
equipment
Scientifi c
equipment
Buoys, ropes,
chains, tyres
Aquaculture
seed-stock
ACCEPTABILITY
:
high
SUCCESS:
moderate
populations and removal of individuals before they reach reproductive maturity is
crucial to the success of algal removal by physical means. Failure to achieve this was
one of the major factors resulting in the failure to control
U
.
pinnatifi da
in south-
ern New Zealand (B. Forrest, pers. comm.). Further, given the ability of many algal
species to regenerate from small fragments, physical removal may actually enhance
a populations spread (Critchley
et al
. 1986; Glasby
et al
. 2005).
Trawling and dredging techniques, which involve pulling large equipment
behind a vessel to collect pest organisms in and on the surface of the sediments,
have been trialled as a means of controlling benthic pest species but are generally
of limited success (see McEnnulty
et al
. 2001 and references therein). Trawling has
been suggested as a possible control method for the Asian date mussel
Musculista
senhousia,
which forms large colonies in intertidal mud fl ats in estuaries and shel-
tered bays (McEnnulty
et al
. 2001). However, since
M
.
senhousia
is also found as a
fouling organism on pylons and other artifi cial structures (Willan 1987), dredging
