Metapopulation dynamics of a Burrowing Owl (Speotyto cunicularia) population in Colorado

Abstract

We banded 555 Burrowing Owls (Speotyto cunicularia) either as adults (after hatch year; AHY) or as young of the year (hatch year; HY) and used capture-recapture models to estimate survival and recapture rates and Leslie matrix models to project population growth over time at the 6,900-ha Rocky Mountain Arsenal National Wildlife Refuge (RMANWR), Colorado from 1990-1994. W e found survival rates for AHY could be pooled across sexes and that survival varied by year. Survival for AHY birds between 1990-1991 was 0.71 and averaged 0.18 for the period 1991-1994 (P = 0.06). Survival for HY birds was lower (0.12) the first year of life than succeeding years (x = 0.62, P = 0.0006). We modeled populations on the Refuge as a combination of birds using `good? and one of two types of `fair? habitats. In all models, the proportion of birds that used the good habitat was not critical to population persistence. Our models suggest that RMANWR could act as a source if the population used the combination of good and an `increasing? fair habitat. Our model also suggests that number of pairs using RMANWR decline (5-20 percent) when we used good habitat combined with 'average' fair habitat.

Parent Publication

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

Citation

Lutz, R. Scott; Plumpton, David L. 1997. Metapopulation dynamics of a Burrowing Owl (Speotyto cunicularia) population in Colorado. 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. 255-259.