Indicator: IW-37 Examples of carp pressures and measures for removal and/or commercial catch
Data
Studies in the 1990s showed that carp made up over 80% of the total fish biomass in the Murray-Darling Basin and as much as 96% in some rivers.
Carp control is being addressed nationally, e.g. see the National Management Strategy for Carp Control 2000-2005 (Source: Carp Control Coordinating Group 2000, National management strategy for carp control 2000-2005, Murray-Darling Basin Commission, Canberra, viewed 15 Nov 2005, http://www.mdbc.gov.au/publications/pdf/national_management_strategy.pdf).
Some of the controlling measures include environmental rehabilitation, the use of chemicals, physical removal, biological control, immuno-contraception and molecular approaches. A National Carp Control Workshop was held in March 2003 to inform people about the "daughterless" project. Daughterless technology has been developed by CSIRO and involves release of an enzyme that induces only male offspring from developing carp.
| Status of carp | Actions undertaken | |
|---|---|---|
| C'wth | Import of live carp prohibited | Checks by customs and quarantine officers |
| QLD | Noxious | Enforcement, education, raising of community awareness |
| NSW | Not declared noxious, but recognised as a pest by policy | Enforcement, education, raising of community awareness, inter-agency cooperation |
| ACT | Not declared a pest | Education, raising of community awareness |
| VIC | Noxious | Enforcement, education, raising of community awareness. Fisheries officers to check use of live bait and transport |
| SA | Exotic | Enforcement, education, raising of community awareness |
| TAS | Controlled Fish | Enforcement, education, raising of community awareness |
| WA | Not declared a pest | Enforcement of non-translocation law, education, raising of community awareness |
Source: Koehn et al. 2004, Carp Management Program Report Lakes Crescent and Sorell 1995 - June 2004,, Inland Fisheries Service, Tasmania, viewed 15 Nov 2005, http://www.ifc.tas.gov.au/carp.html, Table 3, p. 51,
Monthly carp removals from Lake Crescent, Tasmania, February 1995 - October 2004
Source: Koehn et al. 2004, Carp Management Program Report Lakes Crescent and Sorell 1995 - June 2004,, Inland Fisheries Service, Tasmania, viewed 15 Nov 2005, http://www.ifc.tas.gov.au/carp.html, Figure 3, p. 29.
Carp provide a high source of protein. They are quite edible if prepared properly, and have potential as an export fish to Asian and European markets.
Carp can also be used in fertilizer and fish oils have commercial value. About 55 tonnes of carp were caught from the NSW commercial fishery in 2003, valued at $116 000
Source: NSW Fisheries 2003, Status of Fisheries Resources 2001/2002, NSW Fisheries, viewed 9 Dec 2005, http://www.fisheries.nsw.gov.au/science/scientific_outputs.
| Carp (approx only) | Rainbow trout, wild |
| One fillet (159g) | One fillet (159g) |
| 202 calories | 189 calories |
| 3.3g fat | 5.5g fat |
| 1.8g sat fat | 1g sat fat |
| 105mg cholesterol | 94mg cholesterol |
| 28.4g protein | 32.5g protein |
| 529.5 mg potassium | 765mg potassium |
| 78mg sodium | 49.5mg sodium |
Source: Warwicke, M. 2006, Carp or Carpitulation -carp nutritional value, viewed 16 Nov 2005, http://www.goldweb.com.au/virtualversity/wetlands/carpfish.html, carp nutritional value.
What the data mean
Carp have the potential to place pressure on aquatic ecosystems by affecting water quality. However, their presence is also an indicator of the extent to which the aquatic environment has been modified by human action. Carp are seen by all jurisdictions as either a current or potential threat, but efforts to eradicate them may be inhibited by their potential commercial value. Additionally, carp are now so prolific, they are likely to be almost impossible to eradicate.
Data Limitations
Very little quantifiable data are available on the actual impact of carp or their control.
Issues for which this is an indicator and why
Inland Waters - Response of biota - Invasive species
Native fish numbers began declining in the 1800s, long before carp appeared, with the introduction of agricultural, mining and other practices that were not consistent with long term sustainability (eg impact of fishing, river-flow control for irrigation, deliberate clearing of aquatic vegetation, cattle hoofs on river or stream banks and removal of groundcovers and understorey near waterways). This altered the aquatic environment so that it was well suited to carp but no longer well suited to native fish. However, once present, carp can have their own impact on waterways.
The carp's feeding habits can impact on inland waters by denuding riverbeds of vegetation. The fish suck up mud, which is re-suspended when it exits the digestive tract or is spat out again. This can cause significantly higher levels of turbidity and siltation and can block light necessary for photosynthesis from aquatic plants. Without aquatic plants, the waterway becomes more turbid and nutrients remain mobilised instead of being absorbed by plants. Algal blooms resulting from an excess of nutrients can further reduce the amount of light penetrating the water, further hindering photosynthesis.
Examples of pressures from carp, along with either positive or negative changes in these pressures where control or harvesting measures are taken may provide insights into the actual impacts of the animal and the effectiveness of responses.
Other indicators for this issue:
- IW-38 Cane toad distribution
- IW-39 Examples of significant wetland weeds
- LD-40 Current research into pressures and contributions of naturalised introduced species
- BD-09 The change in extent of selected nationally significant invasive species
- BD-10 Examples of native species whose populations have declined where various invasive species have established resident populations
Land - Direct pressure of human activities on the land - Species introduction and species change
Carp are an example of an introduced species which thrives because of human modifications of the environment but which, in turn, may place pressure of their own on the environment. Examples of pressures from carp, along with either positive or negative changes in these pressures where control or harvesting measures are taken may provide insights into the actual impacts of the animal and the effectiveness of responses.
Other indicators for this issue:
- LD-01 The proportion and area of native vegetation and changes over time
- LD-19 Land use and land use change
- LD-40 Current research into pressures and contributions of naturalised introduced species
- LD-20 Total grazing pressure relative to net primary productivity
- LD-35 Temporal and spatial correlation between changing fire regimes and species change
- BD-12 Examples of the impacts of fires on biodiversity
- BD-13 Examples of the impact of grazing on biodiversity
- IW-38 Cane toad distribution
- IW-39 Examples of significant wetland weeds
- BD-09 The change in extent of selected nationally significant invasive species
- BD-10 Examples of native species whose populations have declined where various invasive species have established resident populations
Biodiversity - Pressures on biodiversity - Invasive species
Carp have the potential to be invasive in some environments. Examples of pressures from carp, along with either positive or negative changes in these pressures where control or harvesting measures are taken may provide insights into the actual impacts of the animal and the effectiveness of responses.
Other indicators for this issue:
- IW-38 Cane toad distribution
- IW-39 Examples of significant wetland weeds
- BD-09 The change in extent of selected nationally significant invasive species
- BD-10 Examples of native species whose populations have declined where various invasive species have established resident populations
- LD-19 Land use and land use change
- LD-20 Total grazing pressure relative to net primary productivity
- LD-35 Temporal and spatial correlation between changing fire regimes and species change
- LD-40 Current research into pressures and contributions of naturalised introduced species
- BD-13 Examples of the impact of grazing on biodiversity
Biodiversity - Species, habitats and ecological communities - Government action on species and ecological communities
Varying treatment of carp by different jurisdictions, along with examples of pressures from carp, and either positive or negative changes in these pressures where control or harvesting measures are taken, may provide insights into the effectiveness of responses.
Other indicators for this issue:
- BD-02 Conservation status of nationally significant species and ecological communities, compared with previous years
- BD-03 Summary of measures being implemented to respond to threats to biodiversity from invasive species
- BD-04 Listed threatened species or ecological communities for which recovery action is showing stable or increasing populations
- BD-05 Alignment of State/Territory and Australian Government listing processes
- BD-24 Government investments to protect biodiversity for public good purposes
- CO-02 Number of marine species that are endangered or threatened and changes in population/ distribution of selected threatened species
- CO-33 Number of species legislatively protected, number with management plans or where management actions have been taken
- CO-34 Number and extent of Marine Protected Areas
Further Information
- Carp Management Program (Tasmania)
- Carp or Carpitulation
Carp and fishways
- Automated carp removal from fishways (Stuart and McKenzie 2003)
- National Management Strategy for Carp Control 2000-2005
- NSW Fisheries - Scientific outputs
- Pest Animal Control CRC - Publications and Presentations
Key
Links to another web site
Links to data in the DRS
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