Waterbirds as indicators of ecosystem health in the coastal marine habitats of southern Florida: 1. Selection and justification for a suite of indicator species

• MARES identified environmental pressures that threaten Florida's coastal ecosystems.
• A suite of waterbirds was selected as collectively sensitive to these pressures.
• We review aspects of each waterbird's life history to justify use as an indicator.
• Using a decision tree, each indicator was given a score of 0-to-5 for each pressure.
• Resulting scores showed that the suite was collectively sensitive to the pressures.

The coastal marine environment is currently under threat from many anthropogenic pressures that were identified by the MARES project. Indicators of ecosystem health are needed so that targets can be set to guide protection and restoration efforts. Species of birds that are dependent on coastal habitats are ubiquitous along the coasts of southern Florida. Generally referred to as waterbirds, these species, although not all taxonomically related, share a common dependency on the marine environment for food, nesting habitat, or both. A suite of waterbirds was selected based on their perceived sensitivity to pressures in multiple coastal habitat types. The list of species was refined on the basis of a review of life history for characteristics that might make the species particularly vulnerable. Each selected species was then evaluated for sensitivity to the identified pressures using a hierarchical assessment that took into account the sensitivity, severity, and the temporal and spatial scales of the indicator to the given pressures. The selected suite of indicators was collectively sensitive to all the pressures except one.