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Changes in phenology are occurring from global climate change, yet the impacts of other types of global change on the phenology of animals remain less appreciated. Understanding the potential for synergistic effects of different types of global change on phenology is needed, because changing climate regimes can have cascading effects, particularly on invasive species that vary in their thermal tolerances. Using 25 years of data from 5963 nests and 4675 marked individuals across the entire US breeding range of an endangered predator, the snail kite (Rostrhamus sociabilis plumbeus), we isolated the effects of an invasion of novel prey and warming temperatures on breeding phenology and its demographic consequences. Over this time period, breeding season length doubled, increasing by approximately 14 weeks. Both temperature and the establishment of invasive prey interacted to explain the timing of nest initiation. Temperature and invasive prey played distinct roles: earlier nest initiation occurred with increasing temperatures, whereas late nesting increased with invasion. Ultimately, both nest survival and juvenile survival declined later in the year, such that effects from invasive prey, but not warming temperatures, have the apparent potential for mistiming in breeding phenology by some individuals. Nonetheless, relatively few nesting events occurred during late fall when nest survival was very low, and seasonal declines in nest survival were weaker and renesting was more frequent in invaded wetlands, such that total reproductive output increased with invasion. Variation in demographic effects illustrate that considering only particular components of demography (e.g., nest survival rates) may be inadequate to infer the overall consequences of changes in phenology, particularly the potential for mistiming of phenological events. These results emphasize that species invasions may profoundly alter phenology of native species, such effects are distinct from climate effects, and both interact to drive population change. [ABSTRACT FROM AUTHOR]

We tracked 48 young Crested Caracaras (Caracara plancus) in south-central Florida from fledging through their first year and sought to define the post-fledging pre-dispersal period and the timing and drivers of permanent departure (PD) from the natal area. By examining Euclidean distances between telemetry locations and the nest for each tagged caracara, we defined the post-fledging dependency period as the first 2 mo after fledging, when fledglings remained mostly within 2.5 km of the nest and were dependent on their parents for food. Before PD, young caracaras explored areas as much as 11 km from their nest but returned to the natal area, resulting in areas used by fledglings up to 6 times the average home range size of an adult breeding pair. Some caracaras remained within their parents' home range for several months after fledging, even after becoming independent of their parents for food. A fledgling permanently departed its natal area when telemetry indicated it made an abrupt long-distance movement away from its natal area and did not return. We used generalized linear mixed models and a hierarchical modeling approach to test environmental and biological factors that may affect the timing of PD. The most supported model indicated that PD depended on parental reproductive strategy and on the timing of fledging relative to the length of the breeding season. Birds with parents that raised only one brood remained in the natal area for 11.6–21.0 wk longer than birds with parents that raised multiple broods in the same breeding season; fledglings from the first of two broods departed at a younger age, suggesting that the PD decision is partially triggered by the level of parental investment in the first and subsequent brood. Additionally, birds that fledged early in the breeding season departed the natal area 2.8–12.2 wk earlier than those that fledged later in the breeding season, and birds that were exposed to high heat during the nestling stage departed the natal area earlier than those exposed to less heat. The period between fledging and permanent departure from the natal area is important for the conservation of species with delayed dispersal. When developing a conservation strategy for Florida's caracara population, attention should be paid to protecting areas used by fledglings until PD rather than just focusing on a limited protection zone around the nest. Seguimos a 48 Caracara plancus juveniles del centro-sur de Florida desde que abandonaron el nido hasta su primer año de vida y buscamos definir el período entre el momento que abandonan el nido y el momento en que comienzan a dispersarse así como el momento y los impulsores de su partida permanente (PP) desde el área natal. Mediante el análisis euclidiano de las distancias entre los registros de telemetría y la ubicación de los nidos, definimos el período de dependencia posterior al abandono del nido como los primeros dos meses después del mismo, cuando los volantones permanecían principalmente dentro de los 2.5 km del nido y dependían de sus progenitores para alimentarse. Antes de la PP, los jóvenes exploraron áreas distantes hasta 11 km de su nido, pero regresaron al área natal, resultando en áreas utilizadas por los volantones de hasta seis veces el tamaño promedio del área de campeo de una pareja adulta reproductora. Algunos individuos permanecieron dentro del área de campeo de sus progenitores durante varios meses después de abandonar el nido, incluso después de independizarse de ellos, para la alimentación. Un volantón seguido por telemetría abandonó permanentemente su área natal al realizar un desplazamiento de larga distancia rápido, sin regresar, desde su área natal. Utilizamos modelos lineales generalizados mixtos y un enfoque de modelado jerárquico para evaluar los factores ambientales y biológicos que podrían afectar el momento de la PP. El modelo más aceptado indicó que la PP dependía de la estrategia reproductiva de los progenitores y del momento en que los juveniles abandonan el nido y en relación con la duración de la temporada de cría. Las aves con progenitores que criaron solo una nidada permanecieron en el área natal durante 11.6–21.0 semanas, más que las aves con progenitores que criaron múltiples nidadas en la misma temporada de cría; los volantones de la primera de las dos nidadas partieron a una edad más temprana, sugiriendo que la PP se desencadena parcialmente por el nivel de inversión parental en la primera y las siguientes nidadas. Además, las aves que abandonaron el nido tempranamente partieron del área natal 2.8–12.2 semanas antes que aquellas que abandonaron el nido más tarde en la temporada de cría, mientras que las aves expuestas a altas temperaturas durante la etapa de polluelos partieron del área natal antes que aquellas expuestas a temperaturas más bajas. El período desde que los C. plancus abandonan el nido y la partida permanente del área natal es importante para la conservación de especies con dispersión retardada. Para el desarrollo de una estrategia de conservación de la población de C. plancus de Florida se debería prestar atención a la protección de las áreas utilizadas por los volantones hasta la PP, en lugar de centrarse en una zona de protección limitada alrededor del nido. [Traducción del equipo editorial] [ABSTRACT FROM AUTHOR]

Understanding animal movement often relies upon telemetry and biologging devices. These data are frequently used to estimate latent behavioural states to help understand why animals move across the landscape. While there are a variety of methods that make behavioural inferences from biotelemetry data, some features of these methods (e.g. analysis of a single data stream, use of parametric distributions) may limit their generality to reliably discriminate among behavioural states.To address some of the limitations of existing behavioural state estimation models, we introduce a nonparametric Bayesian framework called the mixed‐membership method for movement (M4), which is available within the open‐source bayesmove R package. This framework can analyse multiple data streams (e.g. step length, turning angle, acceleration) without relying on parametric distributions, which may capture complex behaviours more successfully than current methods. We tested our Bayesian framework using simulated trajectories and compared model performance against two segmentation methods (behavioural change point analysis (BCPA) and segclust2d), one machine learning method [expectation‐maximization binary clustering (EMbC)] and one type of state‐space model [hidden Markov model (HMM)]. We also illustrated this Bayesian framework using movements of juvenile snail kites Rostrhamus sociabilis in Florida, USA.The Bayesian framework estimated breakpoints more accurately than the other segmentation methods for tracks of different lengths. Likewise, the Bayesian framework provided more accurate estimates of behaviour than the other state estimation methods when simulations were generated from less frequently considered distributions (e.g. truncated normal, beta, uniform). Three behavioural states were estimated from snail kite movements, which were labelled as 'encamped', 'area‐restricted search' and 'transit'. Changes in these behaviours over time were associated with known dispersal events from the nest site, as well as movements to and from possible breeding locations.Our nonparametric Bayesian framework estimated behavioural states with comparable or superior accuracy compared to the other methods when step lengths and turning angles of simulations were generated from less frequently considered distributions. Since the most appropriate parametric distributions may not be obvious a priori, methods (such as M4) that are agnostic to the underlying distributions can provide powerful alternatives to address questions in movement ecology. [ABSTRACT FROM AUTHOR]