RETURN AND INCREASE IN ABUNDANCE OF AQUATIC FLOWERING PLANTS IN PUT-IN-BAY HARBOR, LAKE ERIE, OHIO

The initial survey of aquatic flowering plants in Put-in-Bay Harbor, S outh Bass Island, ON, by Pieters (1901), and a follow-up study by Stuc key (1971), documented an overall loss of 50% of the species, and 61% of the submersed species. In the past 25 years, and moreover in the pa st five years, dramatic new changes in the species composition have oc curred in the flora: 1) nine species have returned or appeared for the first time, 2) fourteen species have continued to survive or have inc reased in abundance, and 3) five species have declined in overall abun dance, The return of species requiring clear water for seed germinatio n and growth and the reduction in abundance of species tolerant of tur bid water may be related to the invasions and spread of Dreissena poly morpha (Zebra Mussel) and Dreissena bugensis (Quagga Mussel) which hav e resulted in increasing water clarity. Vallisneria americana continue s to be the dominant submersed, species of Put-in-Bay Harbor.