Is the northern Saw-whet Owl (Aegolius acadicus) nomadic?

Abstract

The first recorded nesting of a Northern Saw-whet Owl (Aegolius acadicus) in the Snake River Birds of Prey Area in southwestern Idaho occurred in a nest box in 1986. Occupancy of nest boxes by Northern Saw-whet Owls varied considerably (0 to 8 nests per year) over the next 10 years. Numbers of rodents fluctuated during this same period, and the number of nesting Saw-whets was positively correlated with an index of rodent abundance. In contrast, the number of nesting Western Screech-owls (Otus kennicottii) in the boxes was not significantly correlated with the rodent index. Moreover, numbers of nesting Saw-whets and Screech owls were significantly positively correlated, indicating that the presence of Screech-owls in the boxes did not have a negative influence on the number of nesting Saw-whets each year.

Parent Publication

• Biology and conservation of owls of the Northern Hemisphere: 2nd International symposium

Citation

Marks, Jeffery S. 1997. Is the northern Saw-whet Owl (Aegolius acadicus) nomadic?. In: Duncan, James R.; Johnson, David H.; Nicholls, Thomas H., eds. Biology and conservation of owls of the Northern Hemisphere: 2nd International symposium. Gen. Tech. Rep. NC-190. St. Paul, MN: U.S. Dept. of Agriculture, Forest Service, North Central Forest Experiment Station. p.260.