A Mini Breeding Bird Survey (MBBS) is a small-scale version of the full Breeding Bird Survey organized each year by the U.S. Fish and Wildlife Service throughout North America. An MBBS focuses on one county. Volunteers count birds seen or heard along randomly chosen routes on secondary roads. The objective is to determine the distribution of breeding birds in the county and to assess any year-to-year changes in their numbers.


An annual MBBS began in Orange County (12 routes) in 1999, in Chatham County (14 routes) in 2000, and in Durham County (8 routes) in 2002. The number of routes in each county varies with the size of the county.

In 2010 we began to use eBird.org to store the results of our surveys. Coordinated by the Cornell Laboratory of Ornithology and the National Audubon Society, eBird.org is now a widely used database for observations of birds worldwide.

By 2012 we had worked out kinks in this process, and we covered all routes in Durham County and all but a few in Orange and Chatham Counties. In 2019, Professor Emeritus at UNC and local legend Haven Wiley retired as organizer of the survey. Allen Hurlbert and Bradley Saul took the reins.

The original MBBS site is available here.


You need not be an expert birder to participate in the MBBS! We just ask that you can:

If you have questions, please contact Allen Hurlbert or Bradley Saul.