Knopik J, Newman R. 2018. Transplanting aquatic macrophytes to restore the littoral community of a eutrophic lake after the removal of common carp. Lake Reserve Manage. 34:365–375. Six native submersed aquatic macrophyte taxa were transplanted to a eutrophic lake (Lake Susan, Minnesota) to promote the growth and expansion of native taxa after the removal of common carp (Cyprinus carpio). Muskgrass (Chara spp.), wild celery (Vallisneria americana), northern watermilfoil (Myriophyllum sibiricum), bushy pondweed (Najas flexilis), water stargrass (Heteranthera dubia), and flat-stem pondweed (Potamogeton zosteriformis) were transplanted in a series of shallow (0.5–1.0 m) and deep (1.0–1.5 m) experimental plots around the lake. Survival and expansion of plants were measured over 4 yr and compared against environmental factors. Transplantation of whole plants in shallow water was generally successful, but plants in depths ≥1.4 m failed to persist. Light availability was the most important factor determining success. Water stargrass was the most successful, with high long-term survival and substantial expansion. Wild celery had high survival, but slow and limited expansion. Bushy pondweed had variable survival, but when it survived it generally expanded well. Muskgrass and northern watermilfoil had poor survival and expansion. Transplanting whole submersed aquatic macrophytes can help to restore the littoral community in degraded systems, but ecological stressors such as common carp should first be addressed. Poor mid-summer water clarity will limit the depth and distribution of successful transplants and taxa that survive. Taxa with large perennial structures such as water stargrass and wild celery are more likely to establish and persist, but the annual bushy pondweed was also able to grow and spread.
Bibliographical noteFunding Information:
This research was funded by the Riley Purgatory Bluff Creek Watershed District with additional support from the USDA National Institute of Food and Agriculture, Hatch grant MIN-41-074. We thank James Johnson, Ajay Jones, Jonathan JaKa, Holly Sigler, and Teran Smith for assistance with data collection and Dr. Peter W. Sorensen, Dr. David Biesboer, Dr. Przemek Bajer, and the watershed district for sharing data, lab, and field resources. Drs. Susan Galatowitsch and Peter Sorensen provided helpful input on early versions of this manuscript. Comments by the reviewers and Associate Editor helped us improve the manuscript.
© 2018, © Copyright by the North American Lake Management Society 2018.
- Heteranthera dubia
- Najas flexilis
- Vallisneria americana
- common carp