Biota removal/disturbance

Green sea turtle entwined in crab trap in Moreton Bay (photo by Ian Greenwood). The removal, loss or disturbance of individual organisms of a specific species results in loss of biodiversity. Biodiversity is the variety of life forms: the different plants, animals and microorganisms, the genes they contain and the ecosystems they form. Maintaining biological diversity is about the sustainable use of biological resources and safeguarding the life-support systems on earth.

View a conceptual model of potential causes of a change to biota removal/disturbance and the condition responses observed as a result of this change.

Potential indicators

There are a number of causes and symptoms related to this stressor. The following indicators are recommended for the stressor ‘Biota (plant or animal) removal / disturbance’:

Pressure indicators

Indicators of biota removal/disturbance sources:

Dredging activity in river system
Recreational bait (beachworm, bloodworm, bait fish, yabby, etc.) collector usage of an estuary
Commercial bait (beachworm, bloodworm and yabby) collector usage of an estuary and adjoining coastal waters
Boat moorings
Boating activity within the estuary
Recreational usage index
'Estuary' population size
Number of recreational fishers using an estuary
Total recreational fisher catch from an estuary
Commercial trawl usage of an estuary and adjoining coastal waters
Commercial line fishing usage of an estuary and adjoining coastal waters
Commercial net and crab fisher usage of an estuary and adjoining coastal waters
Total commercial fisher catch from an estuary and adjoining coastal waters
Commercial licensed collector (of aquarium fish, shell, coral, etc.) usage of an estuary and adjoining coastal waters

Indicators of direct pressure:

None

Vulnerability indicators

None

Condition indicators

Physical-chemical condition indicators:

None

Biological condition indicators:

Commercial finfish catch per unit effort (estimate of fish abundance)
Commercial crab catch per unit effort (estimate of crab abundance)
Commercial prawn catch per unit effort (estimate of prawn abundance)
Recreational finfish catch per unit effort (estimate of fish abundance)
Recreational crab catch per unit effort (estimate of crab abundance)
Recreational prawn catch per unit effort (estimate of prawn abundance)

Possible causes	Possible symptoms
The actions/events/situations that might induce this stress Collecting for bait, shells & aquariums Anchor damage and boat strike Introduced pests Dredging and extraction Fisheries (by-catch & trawling damage) Commercial and recreational fishing Shading of benthos by infrastructure Shark nets/drum lines Harassment by tourist operations Recreational activities (e.g. kite surfing) Boating and shipping	The actions/events/situations that might arise from a change to the stressor: Changes in species composition, behaviour, reproduction, distributions Biodiversity decreased Seafood catch or stock (changed) Visual amenity decreased

Possible causes

Possible symptoms

The actions/events/situations that might induce this stress

Collecting for bait, shells & aquariums
Anchor damage and boat strike
Introduced pests
Dredging and extraction
Fisheries (by-catch & trawling damage)
Commercial and recreational fishing
Shading of benthos by infrastructure
Shark nets/drum lines
Harassment by tourist operations
Recreational activities (e.g. kite surfing)
Boating and shipping

The actions/events/situations that might arise from a change to the stressor:

Changes in species composition, behaviour, reproduction, distributions
Biodiversity decreased
Seafood catch or stock (changed)
Visual amenity decreased

Fact sheets on background science and economics

Other information on direct disturbance to biota

New South Wales

Water Bug Survey. This page has results of water bug surveys used to calculate a Stream Pollution Index for a waterway.

Queensland

EHMP - Coral Monitoring measures the change in biological structure of coral reefs in Moreton Bay over time. Results for 2001 and 2002 coral monitoring are available from this site.

Fish kills . This page has information on fish kill incidents reported to the EPA since March 2002.

Seagrass depth range and distribution. The EHMP website has information on seagrass depth range and distribution in Moreton Bay, southern Queensland.

StrandNet - Marine Wildlife Strandings. The EPA maintains a database of marine wildlife strandings and deaths, called StrandNet. This records information on where injured, dying and dead marine cetaceans (whales and dolphins), pinnipeds (seals and sea lions), dugong and turtles have been found in Queensland.