This US Fish and Wildlife Service filed a report with FERC on the economic value of refuge based recreation across the nation, on Dec 6, 2007. The main objective of the study was to estimate the national impact of refuges on their regional and local economies. This report studied 80 sample refuges (of a total of 548) and presented findings on:

1. Visitor Recreation-Related Expenditures

2. Economic Effects Associated With Refuge Visitation, and

3. Summary of Economic Effects of Refuge Visitation.

Summary findings:

1. In 2006, 34.8 million people visited wildlife refuges resulting in $1.7 billion in sales and $185 million in tax revenues.

2. Activities related to refuge visitation resulted in employment for 27,000 people

It concludes that recreational visits to national refuges generate substantial economic activity.

The report is available here.