Journal Article Bayesian Bayesian hierarchical models Engelmann spruce Markov chain Monte Carlo Monte Carlo Newton-Raphson Monte Carlo expectation maximization Picea engelmannii Pinus flexilis Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. alpine treeline avian communities bird climate climate change climate change experiment colonization/persistence cross-validation drought forecasting global change imperfect detection joint species distribution model land use land use change limber pine maximum likelihood estimation occupancy resurvey