Life cycle of Galerucella calmariensis and Galerucella pusilla . Developing larvae feed on bud, leaf, and stem tissue. Pupation to adult occurs in the soil or litter near the host plant. Adults die soon after the spring ovioposition period. Beetle release sites at Westham Island, Colony Farm, Deas Island, Boundary Bay, and Ladner Marsh are also monitored on a regular basis.
Some areas maintain low beetle densities that have little effect on purple loosestrife stands.
Others, such as the Ladner Marsh and Deas Island sites, still lack beetle populations entirely. To determine if loosestrife competes with native vegetation, we are also conducting experiments at Ladner Marsh. These projects are done in conjunction with community groups to organize beetle rearing and release programs. This summer, in cooperation with the Langley Field Naturalists, over 5000 beetles were reared and introduced to Brydon Lagoon in Langley. Although it may be years before the loosestrife begins to die back, the site seems promising.