CLWA completes aquatic plant survey of Crystal Lake
In early August 2018 the CLWA completed the final phase of its comprehensive, three-year survey of the aquatic plants in Crystal Lake. Under the direction of board member Jim Hamp, and assisted by volunteers and the drone technology of Zero Gravity Aerial, the survey has provided an assessment of the established native species and the extent and types of invasive plants. The full analysis of this data over the coming months will provide the basis for future action.
The 2018 survey focused on the north shore and showed that aquatic invasives in Crystal Lake are still relatively limited in comparison to many other Michigan Lakes. Eurasian watermilfoil predominates, concentrated on the east end around the Beulah public boat launch, with a few other small patches.
Hamp estimates that the total amount of milfoil present is no more than 5 acres, which should be manageable with proper treatment in the future. Unless controlled, invasive plants can easily out-compete and dominate native species of plants, radically changing the health of the ecosystem of the lake.
One concern is that Crystal is very deep in some areas, and these locations are not reachable by current survey methods (either rake toss from a boat or aerial drone). Recent discoveries in Higgins Lake suggest that certain invasives may be present in these depths, which should be examined by additional methods.
The CLWA Aquatic Weed Survey was conducted under the auspices of the Michigan Cooperative Lakes Monitoring Program and was intended to update a study done in 2008. It aims to compare the amount and type of weeds now to those found in the earlier work, and determine if beds are beginning or expanding. The identification and control of invasive species has been a long-time concern of the CLWA, leading to the construction of the boat washing station at the Mollineaux Road launch site in 2013.
For more resources on invasive species, go to: http://crystallakewatershed.org/water-quality/invasive-species