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Spatial memory plays a role in the way animals perceive their environments, resulting in memory‐informed movement patterns that are observable to ecologists. Developing mathematical techniques to understand how animals use memory in their environments allows for an increased understanding of animal cognition.Here we describe a model that accounts for the memory of seasonal or ephemeral qualities of an animal's environment. The model captures multiple behaviours at once by allowing for resource selection in the present time as well as long‐distance navigations to previously visited locations within an animal's home range.We performed a set of analyses on simulated data to test our model, determining that it can provide informative results from as little as 1 year of discrete‐time location data. We also show that the accuracy of model selection and parameter estimation increases with more location data.This model has potential to identify a specific mechanism in which animals use memory to optimize their foraging, by revisiting temporally and predictably variable resources at consistent time‐lags. [ABSTRACT FROM AUTHOR]

Eocene to Oligocene marine carbonate shelf deposits in a continuous core in Baldwin County, Alabama, were evaluated within a sequence stratigraphic framework to determine characteristic stable isotopic responses to inferred fluctuations in sea level. Due to a greater sampling density per unit of time, stable isotopes in this core reveal more defined trends than have previously been reported from DSDP/ODP (Deep Sea Drilling Project/Ocean Drilling Project) records and from more landward sections that have undergone intense subaerial alteration or erosion. The Delta18O signature records eustatic sea level. Delta18O becomes heavier as eustatic sea level falls and lighter as eustatic sea level rises. Delta18O records a secular shift to heavy from the early Eocene to Oligocene of 3.0 per thousand. The Delta13C signature records relative sea-level change (paleobathymetry). Delta13C generally becomes heavier in shallower water deposits and lighter in deeper water deposits. However, in planktonic oozes, Delta13C may shift to heavy. Delta13C also records a secular shift to heavy from the early Eocene to the Oligocene of 3.5 per thousand. Although minor diagenetic perturbations in the stable isotopes are present, the depositional signal dominates the isotopic signal. Spar cements generally result in lighter Delta18O and Delta13C. If the dolomite is >20%, dolomitization results in heavier Delta18O and Delta13C.

Passive integrated transponder (PIT) tags allow a range of individual-level data to be collected passively and have become a commonly used technology in many avian studies. Although the potential adverse effects of PIT tags have been evaluated in several species, explicit investigations of their impacts on small (<12 g) birds are limited. This is important, because it is reasonable to expect that smaller birds could be impacted more strongly by application of PIT tags. In this study, we individually marked Black-capped Chickadees (Poecile atricapillus), a small (circa 10 g) passerine, at the University of Alberta Botanic Garden to evaluate potential lethal and sublethal effects of two PIT tagging methods: attachment to leg bands or subcutaneous implantation. We used a Cox proportional hazards model to compare the apparent survival of chickadees with leg band (N = 79) and implanted PIT tags (N = 77) compared with control birds that received no PIT tags (N = 76) over the subsequent 2 years based on mist net recaptures. We used radio-frequency identification (RFID) redetections of leg band PIT tags to evaluate sex-specific survival and increase the accuracy of our survival estimates. We also used a generalized linear regression model to compare the body condition of birds recaptured after overwintering with leg band PIT tags, implanted PIT tags, or neither. Our analysis found no evidence for adverse effects of either PIT tagging method on survival or body condition. While we recommend carefully monitoring study animals and evaluating the efficacy of different PIT tagging methods, we have shown that both leg band and subcutaneously implanted PIT tags ethical means of obtaining individualized information in a small passerine. [ABSTRACT FROM AUTHOR]

Many important demographic processes are seasonal, including survival. For many species, mortality risk is significantly higher at certain times of the year than at others, whether because resources are scarce, susceptibility to predators or disease is high, or both. Despite the importance of survival modelling in wildlife sciences, no tools are available to estimate the peak, duration and relative importance of these 'seasons of mortality'.We present cyclomort, an r package that estimates the timing, duration and intensity of any number of mortality seasons with reliable confidence intervals. The package includes a model selection approach to determine the number of mortality seasons and to test whether seasons of mortality vary across discrete grouping factors.We illustrate the periodic hazard function model and workflow of cyclomort with simulated data. We then estimate mortality seasons of two caribou Rangifer tarandus populations that have strikingly different mortality patterns, including different numbers and timing of mortality peaks, and a marked change in one population over time.The cyclomort package was developed to estimate mortality seasons for wildlife, but the package can model any time‐to‐event processes with a periodic component. [ABSTRACT FROM AUTHOR]