About


This website is a project of the Rouge River Bird Observatory at the University of Michigan-Dearborn. RRBO's main research focus is the ecology of fall migrant birds in urban areas. Our data have determined that several species of Catharus thrushes gain mass during their fall stopover on campus. Since 2007, a component of this research is examining the fall diet of birds at an urban site.

This fecal sample from an American Robin contained one Rhamnus cathartica
seed, many seeds of Lonicera maackii, and one jewelry clasp!
To do this, we collect fecal samples from the birds that we band or from seed traps, and identify and catalog all the seeds we find. We initially compiled a book of photos of seeds from plants known to occur in the area, as well as a large reference series of seeds collected on campus and nearby. 

Interest in this project from other researchers as well as land managers and homeowners interested in what birds are eating prompted us to create this online reference guide to fleshy, bird-dispersed fruits, especially identification of seeds. It will focus on fall- and summer-fruiting plant species found in southern Michigan, but since many of these species are widespread in North America, it will be useful for a broader region. Both native and non-native species are covered.

A portion of this research resulted in the following paper:
Craves, J. A. 2015. Birds that eat nonnative buckthorn fruit (Rhamnus cathartica and Frangula alnus, Rhamnaceae) in eastern North America. Natural Areas Journal 35:279-287.

Notes on the species accounts


Invasive status is derived from listing in the Invasive Plant Atlas of the United States.

Fruit ripening dates and seed dispersal dates are primarily from The Woody Plant Seed Manual, Agricultural Handbook 727, USDA Forest Service, 2008.

Distribution status in Michigan is primarily from Michigan Flora Online, A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan Herbarium.

Please cite as:

Craves, J. A., and D. Wloch. 2012. Fruit seeds of southern Michigan, an online guide. Rouge River Bird Observatory, University of Michigan-Dearborn. <http://seedguide.blogspot.com/p/index.html>