Effects of Eurasian Watermilfoil on Benthic Macroinvertebrate Communities

Marco Finocchiaro (Montclair State University), Scott Evans (State University of New York at Geneseo) & Jennifer Cocciardi (New York University)

Faculty mentors: Paul Bologna & Meiyin Wu (Montclair State University)

Eurasian water milfoil (Myriophyllum spicatum) has been documented to negatively impact the ecosystem it invades due to its rapid growth rate and its ability to reproduce through fragmentation. It often outcompetes native vegetation and becomes dominant plant species, and further alters the ecosystem composition. This study investigated the impacts of invasive Eurasian water milfoil on benthic macroinvertebrate communities. Three lakes located in Stokes State Forest, Sussex County, New Jersey were selected for this study. Lake Ocquittunk (LO) is dominated with invasive Eurasian milfoil, Lake Wapalanne (LW) with native spiny coontail (Ceratophyllum echinatum), and Sawmill Pond (SP) with a mix of both native and introduced plant species. Ten sites were randomly selected in each lake. One bethic sample (16.5 cm x 16.0 cm) was collected from each site using an Eckman Drege. Macroinvertebrates from samples were identified and counted. LW was found to have the highest density of 600 macroinvertebrates, the highest taxonomic richness of 17 orders, and the highest Shannon-wiener diversity index value of 2.11. LO was found to have the lowest density of 167, the second highest amount of taxonomic groups of 14 orders, and the second highest Shannon-wiener diversity index value of 1.77. SP was recorded to have the second highest density of 453, the fewest taxonomic groups of 13 orders, and the lowest Shannon-wiener index value of 1.61. The results of this study indicated the invasive Eurasian water milfoil negatively impacted the benthic macroinvertebrate communities.

  • Presented at the 44th Annual Fall Conference of the Metropolitan Association of College & University Biologists (MACUB), on October 29, 2011 at South Orange, NJ.
  • Presented at the New York University Undergraduate Student Conference in March 2012.