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Software

Software associated with the Alaska Region.

Nest Survival Bias Analysis

This R script will run one replicate of one scenario used by Weiser (in review) to quantify biases in estimates of nest survival when nests are not found at the beginning of the nesting interval (age 0). The script simulates nest monitoring histories based on input parameters, applies models with or without an age effect to estimate daily survival rates, and calculates nest survival (to the end of

USGS Sea Ice Email Script, 2017

Daily sea ice imagery and charting benefits logistics and navigational planning in the Alaskan Arctic waters, yet access to these data often requires high bandwidth data access and substantial GIS processing.

Model selection in Cormack-Jolly-Seber mark-recapture investigations

Cormack-Jolly-Seber (CJS) mark-recapture models are widely utilized in ecology, providing estimates of vital rates and abundance that are difficult to obtain using other means.

QFASA robustness to assumption violations

Quantitative fatty acid signature analysis (QFASA; Iverson et al. 2004) has become a common method of estimating diet composition, especially for marine mammals, but the performance of the method has received limited investigation.

Pedestrian Evacuation Analyst Tool

The Pedestrian Evacuation Analyst is an ArcGIS extension that estimates how long it would take for someone to travel on foot out of a hazardous area that was threatened by a sudden event such as a tsunami, flash flood, or volcanic lahar. It takes into account the elevation changes and the different types of landcover that a person would encounter along the way.

Quantitative Fatty Acid Signature Analysis in R (qfasar)

Quantitative fatty acid signature analysis (QFASA) is a method of diet estimation introduced over a decade ago (Iverson et al. 2004).