BirdSafe Research

Stephanie Beard

A Nashville Warbler sits stunned from a window collision as a BirdSafe Volunteer approaches to help.

In addition to Lights Out, one of our initial goals when Project BirdSafe began in 2007 was to set up a scientifically sound building monitoring program. Since that first spring a dedicated band of BirdSafe volunteers have traversed a prescribed route in downtown Minneapolis and St. Paul, and also in Rochester looking for birds that have collided with windows.

Read the recent Project BirdSafe Research (PDF) published in The Loon, the magazine of the Minnesota Ornithologist’s Union (Spring 2010)

How can I help?
Join our volunteer team. We monitor buildings on our Minneapolis and St. Paul routes or at other buildings as the need arises. Volunteer training is held periodically. Review the volunteer form for more information.

When are routes walked?
We aim to walk each route every morning during both spring and fall migration periods. This translates to about 11 weeks or 77 days in both the spring and the fall. Because collisions occur at varying times throughout the day we know we miss birds during this one sweep. This spring, a PhD student from the University of Minnesota mobilized an additional group of student volunteers to walk the routes again in the evening during peak migration weeks.

What have we found?
Each year BirdSafe volunteers pick up 500 birds or more from just a handful of buildings being monitored. These birds represent over 100 species. The five most common species we’ve found overall are:

1. White-throated sparrow
2. Nashville warbler
3. Ovenbird
4. Tennessee warbler
5. Dark-eyed junco

Do you ever find rare species?
We have found several birds that are rare in our area including a Townsend’s solitaire, Connecticut warbler and Carolina wren along with several species of conservation concern in the state. In general most of the birds we find are migratory; about ½ are warblers. This spring we picked up a golden-winged warbler and an orchard oriole as part of our routine surveys. In Rochester, volunteers found a Wilson’s phalarope that had hit a Mayo Clinic window.

What happens to the birds?
Fortunately we do find a small percentage of birds alive. Many of them can be released away from buildings after some quiet time. About 90% of the birds we find unfortunately are dead. These birds still have great value to science. They all go the University of Minnesota’s Bell Museum of Natural History where they are preserved as a spread wing and tissue sample (good for DNA extraction, pesticide analysis, etc.). Upon dissection, we determine each bird’s sex, age, molt status, fat condition and what it had been eating immediately prior to its death. In this way, each bird strike is scientifically documented and the birds themselves serve to help us learn more about this problem.

What conclusions have we made so far?
Among the surprising conclusions of our work so far is the fact the birds hitting buildings most often are not simply the most common birds in our area. Many abundant birds like the yellow-rumped warbler make up a very small percentage of our findings. We also know that not all buildings pose an equal threat to birds and that some of the buildings with the highest mortality probably represent more of a threat on average during the day than at night.

How long will research continue?
We will continue to monitor our existing research routes to build upon what we have learned so far at least for the next few years. We are also continuing work with master’s and PhD students at the University of Minnesota on additional questions. We also continue to establish monitoring at certain buildings outside of our established routes as building staff and tenants show a willingness to do so