|
Cockle
|
Tractor towed dredge
Hydraulic dredge
|
·
Intertidal dredge tracks visible for varying
amounts of time ie. Months in stable sediments,
a tide in mobile sediments.
·
Sediment layers may be altered causing erosion
to cockle bed.
·
Significant reduction in biomass of target
and non target species immediately after fishing
operation. Likely to be more pronounced with
extended recovery times, ie many months, in
areas with diverse communities and stable
conditions.
|
|
Oysters and mussels
|
Dredge
|
·
Subtidal and intertidal dredge tracks visible
for varying amounts of time, ie. months in
stable sediments, hours in mobile sediments.
·
Top 10-15 cm of substrate disturbed and sediment
plumes created
·
Change in benthic flora and fauna as a consequence
of repeated dredging.
|
|
Clams
|
Hand gathering
|
·
Holes and tailings left on the intertidal
visible for varying amounts of time, ie. months
in stable sediments, a tide in mobile sediments.
·
Under size target species damaged or exposed
to predation, desiccation or freezing.
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