Managing Loggerhead Shrike Habitat Using Remote Sensing Products

The prairie population of the loggerhead shrike (Lanius ludovicianus excubitorides) is dependent upon two characteristics of a grassland landscape that require specific management to maintain: shrubs taller than 1.8 m tall for nesting and tall grass for foraging. The purpose of this study is to measure the landscape variables that are important to loggerhead shrike persistence at landscape spatial scales to help understand the impact of management decisions and seek alternative solutions if required. Results indicated that shrikes prefer to nest in scattered shrubs, particularly thick or thorny species. Reflectance based vegetation indices differed in their performance dependent upon the vegetation variables used. L-ATSAVI and ATSAVI are the best LAI estimators, while MSAVI2 is good to estimate the shrub cover. A logistic regression model, using loggerhead shrikes active or inactive nesting as the dependent variable and biophysical, topographical, and remotely sensed data extracted from both ground and space, as the predictors was developed. The predictive performance of the selected models was shown to be high, indicating a good fit of the model to the data. Further analysis showed that all the variables considered (Dead cover in tall shrub habitat and ATSAVI) had significant, independent contributions towards explaining the variation in the dependent variable. The selected model clearly delineated areas predicted as highly suitable loggerhead shrikes habitat.