DETERMINING THE PRESENCE OF NON-NATIVE AQUATIC SPECIES IN RECREATIONAL BOAT HARBORS IN CHICAGO, ILLINOIS

The spread of aquatic invasive species (AIS) creates ecological and economic problems that are often long-term and difficult to manage. The movement of recreational boats is a well-known vector for unintentional AIS transport in the Great Lakes region. An area with particularly high recreational boat activity is Chicago, which has a high population density, harbors on Lake Michigan, and several boat ramps that allow overland access to many other waterbodies. Because of this, Chicago’s recreational harbors may be a hub for the spread of AIS. In the summer of 2023, I sampled nine recreational harbors in the Chicago region to identify the presence and abundance of non-native macrophytes and macroinvertebrates. Macrophyte sampling at each harbor was conducted via 10 tosses of a doubled-sided rake, and macroinvertebrates were sampled with rock bags, Hester-Dendy samplers, and scraping. Non-native macrophytes were present at seven harbors and included Myriophyllum spicatum (n=5 harbors), Nitellopsis Obtusa (n=2), and Potamogeton crispus (n=1). These are the first records of N. obtusa in the Chicago region, and also new records for M. spicatum and P. crispus. Macroinvertebrate sorting is ongoing. My results show that recreational harbors can be important sites for the establishment of new AIS. In particular, N. obtusa is a high priority species that had not previously been identified in the Chicago region. Its establishment in harbors means that it is likely to spread further on boats traveling on water and overland.

Primary Presenter: Alex Quebbeman, Loyola University Chicago (aquebbeman@luc.edu)

Authors:

Alex Quebbeman, Loyola University Chicago  (aquebbeman@luc.edu)

Reuben Keller, Loyola University Chicago  (rkeller1@luc.edu)