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Telemetry technology is ubiquitous for studying the behavior and demography of wildlife, including the use of traditional very high frequency (VHF) radio telemetry and more recent methods that record animal locations using global positioning systems (GPS). Satellite‐based GPS telemetry allows researchers to collect high spatial–temporal resolution data remotely but may also come with additional costs. For example, recent studies from the southern Great Basin suggested GPS transmitters attached via backpacks may reduce the survival of greater sage‐grouse (Centrocercus urophasianus) relative to VHF transmitters attached via collars that have been in use for decades. While some evidence suggests GPS backpacks reduce survival, no studies have examined the effects of GPS backpacks on breeding behavior and success. Therefore, we compared survival, breeding behavior, and nest success of sage‐grouse hens marked with both VHF collars and GPS backpack transmitter over a 7‐year period in central Idaho, USA. GPS backpacks reduced spring–summer survival of sage‐grouse hens relative to hens with VHF collars, where daily mortality probability was 68%–82% higher from March 1 to August 1. Yet satellite GPS backpacks did not consistently affect nest success or the likelihood or timing of nest initiation relative to VHF collars. Daily nest survival varied annually and with timing of nest initiation and nest age, but marginal effects of transmitter type were statistically insignificant and interactions between transmitter type and study year produced no meaningful patterns. Our results corroborate recent studies for the effect of satellite GPS backpacks on sage‐grouse survival, but also suggest that these transmitters do not appear to affect components of fecundity. Our results therefore add important context to recent debate surrounding the effects of GPS backpacks on sage‐grouse, and the relative strengths and weaknesses of different transmitter types for understanding behavior and population dynamics. [ABSTRACT FROM AUTHOR]

Fish often exhibit complex movement patterns, and quantification of these patterns is critical for understanding many facets of fisheries ecology and management. In this study, we estimated movement and fishing mortality rates for exploited walleye (Sander vitreus) populations in a lake-chain system in northern Michigan. We developed a state-space model to estimate lake-specific movement and fishery parameters and fit models to observed angler tag return data using Bayesian estimation and inference procedures. Informative prior distributions for lake-specific spawning-site fidelity, fishing mortality, and system-wide tag reporting rates were developed using auxiliary data to aid model-fitting. Our results indicated that posts-pawn movement among lakes was asymmetrical and ranged from approximately 1% to 42% per year, with the largest outmigration occurring from the Black River, which was primarily used by adult fish during the spawning season. Instantaneous fishing mortality rates differed among lakes and ranged from 0.16 to 0.27, with the highest rate coming from one of the smaller and uppermost lakes in the system. The approach developed provides a flexible framework that incorporates seasonal behavioral ecology (i.e., spawning-site fidelity) in estimation of movement for a mobile fish species that will ultimately provide information to aid research and management for spatially structured fish populations. Les poissons presentent souvent des motifs de deplacement complexes, et la quantification de ces motifs est essentielle a la comprehension de nombreuses facettes de l'ecologie et de la gestion des ressources halieutiques. Nous avons estime les deplacements et les taux de mortalite par peche pour des populations exploitees de dores jaunes (Sander vitreus) dans un reseau de chaines de lacs dans le nord du Michigan. Nous avons elabore un modele d'espaces d'etats pour estimer les deplacements et des parametres touchant a la peche dans differents lacs et avons cale le modele sur des donnees de retour d'etiquettes par des pecheurs en utilisant des procedures d'estimation et d'inference bayesiennes. Des distributions a priori informatives pour la fidelite aux lieux de frai selon le lac, la mortalite par peche et la frequence de signalements d'etiquettes a l'echelle du reseau ont ete produites en utilisant des donnees auxiliaires pour aider au calage du modele. Nos resultats indiquent que les deplacements entre les lacs apres le frai etaient asymetriques et allaient d'environ 1%a 42 % par annee, la plus grande devalaison s'etant produite a partir de la riviere Black, qui etait principalement utilisee par des poissons adultes durant la periode de frai. Les taux de mortalite par peche instantanee variaient selon le lac et allaient de 0,16 a 0,27, le taux le plus eleve etant observe dans un des lacs les plus petits et les plus en amont du reseau. L'approche mise au point fournit un cadre souple qui integre l'ecologie des comportements saisonniers (c.-a-d., la fidelite aux lieux de frai) dans l'estimation des deplacements pour une espece de poissons mobiles qui fournira, a terme, des renseignements qui aideront a la recherche et a la gestion pour des populations de poissons structurees dans l'espace. [Traduit par la Redaction], Introduction Fish demonstrate variable movement patterns and complex spatial structures among open systems that can complicate decisions related to harvest management and species conservation. Given these challenges, estimating movement rates [...]