Drumming Ruffed Grouse

Species differences in courtship behaviour are associated with evolutionary changes in the anatomy of the brain. However, the vast majority of these studies focus on vocalizations, with relatively few studies addressing the neural basis of non-vocal courtship.

Over the past 8 years, one of the research goals of the Iwaniuk lab is to better understand how Ruffed Grouse (Bonasa umbellus) produce and perceive their unique wing beating display known as drumming. To date, we have described the bioacoustic properties of this display, examined the anatomy of the inner ear and looked at the expression of the steroidogenic enzyme, aromatase, throughout the brain. Recent MSc students have examined wing morphology, seasonal differences in brain anatomy, responses to playbacks and variation in drumming behaviour in relation to body size.

The Ruffed Grouse is a very challenging species to work with. Weather conditions at our field sites change dramatically and trails are often a combination of mud and snow. However, for intrepid students interested in studying a cryptic bird with an unusual behaviour, the drumming display, working with them can be a lot of fun and you will get to see a lot of other wildlife (bears, cougars, goshawks, owls, pine martens, moose, to name a few). Currently, we are addressing the following questions:

1) Are seasonal changes in the size of arcopallium due to changes in neuron morphology?

2) What is the expression pattern of androgen receptors in the pectoral muscle and spinal cord of drumming males? (in collaboration with Matt Fuxjager, Wake Forest University)

3) Do Ruffed Grouse have adaptations in their muscle histochemistry that permit drumming? (in collaboration with Ken Welch, UT-Scarborough)

4) How far does the drumming sound propagate in different environments?