The 21 acre Stone Harbor Bird Sanctuary is internationally known by ornithologists and bird lovers for its value as a significant wading bird breeding habitat and migratory songbird stopover.  The site is a historical heronry, formerly host to thousands of colonial water-birds such as the Black-Crown Night Heron, Snowy Egret, Great White Heron, Little Blues and Tricolor Herons.  Many species of songbirds use the sanctuary as their migratory stopover.  In the 10 years prior to implementing the Duffield recovery and restoration plan, most of the wading birds disappeared due to invasion of non-native plant species and loss of tidal flow.  Additionally, predators such as raccoons, rats, feral cats, etc. preyed on birds and bird eggs.

STONE HARBOR BIRD SANCTUARY2Duffield Associates was awarded a contract for a comprehensive habitat and resource inventory and environmental restoration program. Duffield’s team of scientists and engineers spent over a year investigating and documenting current conditions, and the development of a comprehensive Master Plan that was used to develop funding and guide long term implementation strategies. Duffield’s services included:

  • Site Reconnaissance/Research/Inventory
  • Reference Community Assessment
  • Baseline Ecological Evaluation (BEE)
  • Topographic Survey/Mapping to USACE Standards
  • Historical Conditions Assessment
  • Meetings with Regulators and Conservation Groups
  • Master Plan Development
  • Goals and Success Criteria Establishment
  • Funding Identification/Grant Application
  • Development and Implementation of Community Involvement Programs
  • Environmental Site Assessment
  • Development of Site Model
  • Installation/Monitoring of Piezometers
  • Groundwater Monitoring
  • Installation/Monitoring of Tide Gages
  • Wetland Delineation and Permitting
  • Site Hydraulics/Tidal Incursion Modeling
  • Design of New Tidal Inflow Pipe and Control Structures
  • Trail Design
  • Development of Longer Term Maintenance and Corrective Action Plans
  • Develop Cost Estimates

After much of the longer term environmental restoration and other site features were completed, the number of visiting, nesting, and roosting colonial wading birds has increased; native flora and fauna are making an impressive comeback, song bird and migratory bird populations are at impressive levels and controlled public access and educational programs have made this an important ecotourism destination.

This project has won numerous awards including the American Council of Engineering Companies (ACEC) Delaware Chapter Engineering Excellence Honors Award for 2012.