THE USE OF GRASS CARP IN AQUATIC WEED CONTROL

Before stocking Grass Carp, a biomass assessment and investigation of your water resource is essential. This allows for the design of a specific stocking model and program, best suited to the conditions, so that the best possible results in the control of aquatic vegetation can be achieved.

WHAT TYPE OF WEED DO I HAVE?

http://aquaplant.tamu.edu/plant-identification/

We have compiled a questionnaire to assist in the planning of a stocking program that suites your water body. This helps us spend less consulting time in gathering the required information, meaning that you receive your fish sooner to achieve better end results.



The use of Grass Carp in the control of aquatic plants has many advantages such as:

  • Eliminates vegetation cost effectively (cheaper than by herbicides or manually).
  • It is safer and environmentally friendlier than control by chemicals and herbicides.
  • As these fish live long they control vegetation over many seasons.

Factors to consider when using Grass Carp:

  • Insecticides, herbicides, copper based algaecides and other chemicals are harmful to grass carp and other fish and should be used with extreme care.
  • Grass Carp can be used effectively under a wide range of conditions.
  • Grass Carp are difficult to catch on hook and line.
  • Grass Carp tolerate a wide temperature range and climatic conditions. Their feeding behavior is however influenced by water temperature and season.
  • They are selective feeders, favouring certain plant species. The aquatic plant community must be well understood and a stocking program designed accordingly.
  • Grass Carp grow rapidly, reach a large size (15 kg.+) and are long-lived.
  • Depending on the conditions 20 to 30 fish are usually stocked per hectare of water.
  • Stocking too few fish will have little effect, while overstocking can eliminate plant cover completely, leading to turbidity and deterioration of water quality that can cause ecological imbalances.
  • Grass Carp stocking can lead to water nutrification in closed systems through rapid circulation of nutrients tied up in water plants.
  • Grass Carp will migrate out of water impoundments if given the opportunity. Inlets and outlets of the dam must be screened up to one meter high.
  • Grass Carp could influence other fish species. Through correct management this influence can be used advantageously to promote the well being of other species.
  • Bass, birds and otters can reduce fish numbers if stocked at an inappropriate size.
  • During the first year after stocking, few fish will be seen and results will only be detected the second year.
  • Grass Carp will not effectively controll algae, water hiasinth and some reed species.

Current prices (excluding VAT) for certified sterile, disease free Grass Carp (subject to change without prior notification) are:

View our pricelist here
 

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