Mission: Hungry, Hungry Beetles
Student scientists at Massabesic Middle School in East Waterboro have observed an apparent balance of invasive Lythrum salicaria and non-native Galerucella beetles on their school grounds. Can they replicate this balance on a larger scale by introducing Galerucella to a larger site where loosestrife is spreading?
Student scientists have been monitoring invasive Lythrum salicaria since 2010 on their school grounds (Mission: Massabesic). They have discovered what seems to be an ecological balance with Galerucella, a non-native beetle species released in southern Maine, that seems to be keeping the one known loosestrife plant on campus from spreading. Japanese beetles, an invasive species, seem to be helping to keep loosestrife flowers in check each fall while Galerucella feeds on the leaves.
Students have read and learned a lot about Galerucella since identifying it on campus soon after Lythrum salicaria was first discovered. They have learned about the successful introduction of Galerucella on the Rachel Carson National Wildlife Refuge in Wells, Maine. This collaborated effort by the US Fish and Wildlife Service and the York County Soil and Water Conservation District is sited by many for its practical approach of raising Galerucella as a biological control of loosestrife by using their coauthored protocol titled Beetle Rearing Guide.
Because students have found what seems to be a balance between loosestrife and Galerucella on their campus, they now want to try to achieve a balance on a larger scale.
Student scientists at Massabesic Middle School have begun to follow an established protocol for raising and introducing Galerucella to a nearby area infested with Lythrum salicaria. They plan to predict, and then monitor the change in the loosestrife and Galerucella popultations over time.
Mission Timeline & Methods
1. Identify loosestrife at the new site and submit the findings to Vital Signs
2. Measure the overall area of coverage of loosestrife at the new site
3. Do a quadrat count of the number of loosestrife stems to gauge the density of loosestrife
4. Measure the average height of the loosestrife
5. Search for evidence of the presence of Galerucella and Japanese beetles
Winter/ Spring 2013
Students will research and prepare a site on the Massabesic Middle School campus to raise Galerucella. Established protocols for gathering and growing loosestrife, collecting, raising and releasing Galerucella will be followed by following the Beetle Rearing Guide. The basic procedure is summed up as follows:
Spring/ Summer 2013
1. Dig up and gather loosestrife root crowns in early spring
2. Grow loosestrife on campus
3. When plants are big enough (.5 meter height), collect Galerucella from an established site
4. Release collected beetles on campus plants and cover with nets
5. Allow Galerucella to live out its life cycle (laying eggs, hatching larvae etc.)
6. Bring plants with Galerucella to the loosestrife infested site and remove nets to release beetles in mid summer
Students will monitor the change over time of the loosestrife and Galerucella populations. Specific things that will be monitored include the change in height of the plants and over time as well as the density. The standardized protocol of Bernd Blossey of Cornell University for post-release monitoring of Galerucella on Lythrum salicaria will be followed as closely as possible.
For more information about this Mission, please leave a comment below for Pat Parent and his MassabeSci team!