The Effect on Model Identi ability of Allowing Different Relocation Rates for Live and Dead Animals in the Combined Analysis of Telemetry and Recapture Data

Models are described for the joint analysis of live-trapping and radio telemetry data from a study on black bears (Ursus americanus) in which all animals received ear tags and a subset also received radio tags. Concerns about bias in survival estimates led to investigation of identi ability and estimator precision for a series of models that allowed different telemetry relocationrates for livingand dead animals, in additionto emigrationand seasonal variation in survival. Identi ability was determined by showing that the expected information matrix was nonsingular. Models with delity constant across time, and with the same degree of time speci city for survival rates and relocation rates for dead animals, were determined to be nonidentiable. More generalmodels, with a greater degree of time speci city for survival rates, were near-singular, and estimators under these near-singular models had poor precision. Analysis of data from the study on black bears illustrated that estimates of survival have poor precisionwhen relocation rates are estimated separately for live and dead animals. It is recommended that the effort expended to relocate both living and dead animals be consistentlyhigh in each telemetry survey, so that relocation rateswill be high and constant across time and mortality status