Puget Sound Bird Observatory has been providing avian monitoring at zis a ba for the Stillaguamish Tribe of Indians to better understand avian response to estuary restoration. In the course of that monitoring, observers have documented the general character of the site which includes a well-established Great Blue Heron colony nesting area located on the west edge of the project area.
Zis a ba herons have utilized this habitat for both nesting and roosting and are present seasonally in large concentrations to nest, and in smaller year around roosting aggregations. Tree die-off, due to the salt water intrusion to restore estuary conditions to the site, has compromised the structural integrity of the heronry and many of the existing nests/ roosts are disintegrating as the limbs they rely on for support are breaking from the tree.
According to the literature (1981, Meier), Birds of North America website (BNA Online), and Cornell Nest Watch program, there has been some success with installing artificial nesting platforms for Great Blue Heron and Double Crested Cormorant.
PSBO, with the support of the Stillaguamish Tribe Natural Resources staff, installed ten (10) nesting platforms across five poles on the upland dike behind the existing heronry. Restoration planting near the base of the artificial platforms will begin the process of building up buffer habitat to support new and additional nests in the future.
Logistics for this project were complicated due to high tides and a narrow tidal range throughout the month prior to nesting. In addition, materials needed to be floated to the site and off-loaded for the final construction and installment.
PSBO will provide monitoring of the heron colony to assess the use of artificial nest platforms with an eye toward other declining heronry sites, particularly in restoration areas, that may benefit from a similar approach.