On Friday February, 17, Drew Jones visited Log Lunch from Hopkins Forest to discuss his project tagging Migrant Northern Saw-Whet Owls. The tagging takes place in Hopkins Forest to clarify the answer to: What is the nature of migration?
Wildlife agencies do not know much about these owls because they are very secretive and have been noted in very odd places. Drew’s study works to collect more information on the population. They would like to characterize what is driving migration and if populations migrate differently depending on sex or age. What are the drivers of migrations? Resource availability? Breeding range? These are all question Drew and his fellow owl taggers would like to find out.
Drew captures these owls in Hopkins Forest using four large mist-nets. The bats are lured toward the nets by sound. Drew and his team check the nets every 45 minutes and when an owl is caught, they are taken inside for measurements and data collection.
Through this method, Drew’s team has recognized that Saw-Whets in this area tend to be female, and older when compared to other station data around the country. He has also recognized that the moon deters their migration movement. This is due to increased danger when the moon is brighter. Therefore, if there is a full moon, catching owls is very rare. The team catches the most owls when cloud cover is less and the wind speed and temperatures are lower. Drew hypothesizes that the cooler temperatures may be less stressful for an owl while flying, and winds may increase the energetic cost of flight. Cloud coverage may obscure navigational points, therefore owls are less likely to fly on cloudy days.
Drew will continue his Saw-Whet tagging project and hopes to expand the knowledge on these tiny birds of prey.
If anyone is interested, owl tagging begins in Hopkins Forest October 1st, 2017!
-Caroline Beckmann ’17