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Providing evidence to improve practice

Individual study: High-density grass carp stocking effects on a reservoir invasive plant and water quality

Published source details

Garner A.B., Kwak T.J., Manuel K.L. & Barwick D.H. (2013) High-density grass carp stocking effects on a reservoir invasive plant and water quality. Journal of Aquatic Plant Management, 51, 27-33


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Parrot’s feather: Biological control using herbivores Control of Freshwater Invasive Species

A replicated, controlled, paired sites study from July 2005 to September 2007 in a reservoir in North Carolina, USA (Garner et al. 2013) found that high-density stocking with grass carp Ctenopharyngodon idella reduced the abundance of parrot’s feather Myriophyllum aquaticum. For five out of six comparisons, the biomass of parrot’s feather was lower in areas available for grass carp (0–113 g/m2) than in areas where grass carp were excluded (0–1330 g/m2)). During the second year of the experiment no vegetation was detected in quadrats located in areas accessible to grass carp. Grass carp density was 100 fish/vegetated ha and grass carp were excluded from eight 6 m2) areas using 1.3 cm plastic mesh. Vegetation in six 6 x 1 m quadrats was sampled monthly from July to September each year.