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Recovery of Eelgrass (Zostera marina L.) in Casco Bay, Maine, Following Destruction by European Green Crabs

Science Center Objects

The Challenge:  Eelgrass provides essential functions to the ecology and economy of Maine’s coastal zone. When over half the eelgrass in Casco Bay, Maine, disappeared between 2012 and 2013, USGS experimental evidence identified disturbance from invasive European green crabs as the leading cause. Loss of vegetation is expected to precipitate a range of impacts, including reduced fish and wildlife populations, degraded water quality, increased shoreline erosion, and reduced capacity to remove anthropogenic carbon dioxide emissions and mitigate coastal acidification. Therefore, reversing eelgrass loss in Casco Bay is of critical ecological and economic importance.

The Science: We are applying the existing SDM framework to five northeastern refuges (Chincoteague, Bombay Hook, Cape May, Forsythe, and Rhode Island Complex). We engaged regional and refuge biologists and managers in a workshop to identify refuge-specific potential actions to achieve management objectives and predict the outcomes of management actions. Using this information, we are implementing constrained optimization to identify the management actions that maximize management benefits subject to budget constraints

The Future: SDM provides a systematic, transparent approach for connecting the outcomes of complex management decisions to overall management objectives. On northeastern National Wildlife Refuges, integrating salt marsh integrity monitoring within a decision context has ensured that monitoring data can be used to improve the quality of complex management decisions.