About the CLWA
CLWA News
Swimmer’s Itch Data from Congregational Assembly Beach 2019
The Congregational Summer Assembly beach, on the southwest corner of Crystal Lake, has been producing the most complete and accurate data on the occurrence of swimmer’s itch since 2013. The latest statistics, from the 2019 season, have now been analyzed and summarized by Al Flory of the CLWA Swimmer’s Itch Partnership. Flory’s report emphasizes two important conclusions: incidence of swimmer’s itch is higher when there are onshore winds and during the morning hours. There is also evidence that swimmer’s itch on Crystal Lake may be stabilizing or decreasing.
Protecting Crystal Lake Now for Generations to Come.
P.O. Box 89 • Beulah, MI 49617
info@crystallakewatershed.org
231.882.4001 Tel
The Crystal Lake Watershed Association (CLWA), is a non-profit (501c3) organization.
Photography: Jay Burt and Rick Cosaro
Site by: Rick Cosaro
Quagga Mussel (Dreissena rostriformis bugensis)
A close relative of the Zebra mussel which already infests Crystal Lake. Like its cousin, it consumes native phytoplankton and clogs lakeshore recreational equipment. More rounded shell and less prominent dark rings than the Quagga. Can grow to 2 inches in length.
New England Mudsnail (Potamopyrgus antipodarum)
Small dark snails that reproduce rapidly to high densities in many habitats. Their small size makes them difficult to detect when attached to fishing gear or watercraft. They are abundant in the Platte River.
Red Swamp Crayfish (Procambarus clarkii)
Dark red color with bright red raised spots: look like small lobsters. Length 2.2 - 4.7 inches. Compete aggressively with native crayfish for food and habitat. Introduced by live bait dumping, aquarium trade.
Hydrilla (Hydrilla verticillata)
Submerged aquatic plant; green leaves whorled in groups of 4-8. Very slender stems can grow up to 30 feet long. White 3-petaled flowers. Forms dense mats that shade out native vegetation and interferes with recreational activities.
Starry Stonewort (Nitellopsis obtusa)
Submerged whorls of 4-6 leaves with blunt tips; can reach up to 33 inches. Forms dense mats that significantly reduce the diversity of other aquatic plants. Mats impede movement of fish, water flow, and recreational activities.
