Raptor survey zeroes in on birds of prey

SOLON — It's a cool, drizzly morning and Shawn Hawks and Brandon MacDougall are driving the country roads of Johnson County in search of raptors like American kestrels, bald eagles and rough-legged hawks.

It's late February and the duo is scouring for these large and powerful birds of prey — characterized by sharp beaks and strong talons — hoping to spot them high up in distant trees, soaring over creeks or circling farm fields.

'Stop,' calls MacDougall from the passenger seat, as Hawks pumps the brakes of a University of Iowa minivan that is on a road northeast of Iowa City. MacDougall points to a tree 30 yards in the distance where a bird with orangish tail feathers and an ivory-colored belly is perched on an upper branch.

'That's a red-tail hawk,' Hawks confirms, pulling binoculars close to his eyes. 'You can tell because of the white chest.'

Hawks is coordinator of the Iowa Raptor Project, a program sponsored by the University of Iowa Recreational Services and Kirkwood Community College, and MacDougall is a doctoral student in the University of Iowa Department of Geographical and Sustainability Sciences. They are working on a winter raptor survey, a 'citizen science project' that aims to gather data about the distribution and abundance of raptors around Johnson County. While researcher know a great deal of breeding and biology, there's a gap in knowledge about wintering, they said.

Hawks proposed the survey as a long-term project for his group and found allies through graduate students. Others volunteer to collect data as well.

The three-month survey began in December.

'It can teach us what's here and where they are,' MacDougall said.

The surveyors jot down the GPS coordinates where they find each bird, the type of bird and the landscape feature. The sheet work also notes the time, wind pattern and weather conditions.

Surveying involves six different vehicle routes about 30 miles each covering large swathes of Johnson County. The routes were built using geographic information system mapping to capture a variety of landscapes.

'The idea was to capture a good amount of variability of the landscape across the county, from urban areas to agricultural land and everything in between,' MacDougall said.

Surveyors, such as Hawks and MacDougall, drive the routes at slow speeds twice each month to collect data. The route takes two to three hours and they generally compile a list of 20 or 30 birds each time, they said.

The data could help draw connections between types of birds and the ground cover each prefers, such as if a particular bird gravitates to tree cover versus open land or impervious surfaces.

Over time, the information could help researchers assemble metrics about population trends in species, migration patterns, habitat preferences and potentially provide more broad indicators such as for climate change. The plan is to continue the surveying for years to come and researchers say with time, the data will become more meaningful.

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