Sharp-shinned Hawk Project

During the spring of 2016, BBRR banders started to notice deformed mouths on some of the Sharp-shinned Hawks that were captured at our banding stations.  Closer examination revealed some lesions on the inside of bird’s mouths.  After discussion with other raptor banders around the country, this was a relatively new issue being documented in this species. 

There were some guesses about what the infection might be, but no one had actually done the laboratory work to figure out what it was.  In the spring of 2017, some infected birds were transported to Cornell University, where Dr. Sara Childs-Sanborn treated them and determined that the infection was a capillarid nematode Eucoleus dispar.  Her results were published in 2019 (Journal of Wildlife Diseases, 55(4): 928-934). 

This parasitic infection is common in raptors, though usually does not present itself in such an obvious, and graphic, way.  The banders at BBRR have been making more careful examinations of Sharp-shinned Hawks over the past few years, concluding that it is now present in about 42% of those banded at Braddock Bay.  We do not know why this infection is being seen now, when it was not seen in earlier years.  Is it related to some toxin that the birds are being exposed to?  It is related to habitat changes?  Most importantly, we do not know how this infection might impact a bird’s overall health and survival. 

BBRR has been pushing forward on the investigation into the observed oral lesions on Sharp-shinned Hawks.  We are continuing to examine and document all the sharpies that we capture, and are expanding this study to other stations around the continent as well. 

2022 BBRR intern Eliana Heiser presented a poster on the project at the October 2022 Raptor Research Foundation Conference.  View the poster here: Raptor Research Foundation Conference Poster on SSHA Study

For more information, and inquiries on how to get involved with this project, contact David Mathiason at 

Resources for Raptor Banders and Researchers

Grading System for Lesions and Fat Scale
Illustrated Oral Lesion Grading System
Muscle Mass Scoring

Sharp-shinned Hawk Study Reports

Project Data Summaries - 2020-22

These documents summarize the Sharp-shinned Hawk data collected during the spring seasons of 2020, 2021, and 2022 by Braddock Bay Raptor Research, as well as the fall seasons of 2020, 2021, and 2022 by Cedar Grove Ornithological Research Station.  

Sharp-shinned Hawk Study – Data Summary for the spring seasons of 2020-2022, Braddock Bay

Sharp-shinned Hawk Study – Data Summary for the fall seasons of 2020-2022, Cedar Grove

Project Report - April 2022

This article was published in the Braddock Bay Raptor Research newsletter, Inside the Kettle, April 2022.

Sharp-shinned Hawk Study Update – April 2022


Project Report - September 2020

This article was published in the Braddock Bay Raptor Research newsletter, Inside the Kettle, September 2020

Sharp-shinned Hawk Study – September 2020