Spatially anonymized data from: Novel step selection analyses on energy landscapes reveal how linear features alter migrations of soaring birds

This dataset consists of spatially anonymized movement data as well as
environmental covariate data to estimate energy landscape step selection
selections for migratory golden eagles that summer in Alaska. Human
modification of landscapes includes extensive addition of linear features,
such as roads and transmission lines. These can alter animal movement and
space use and affect the intensity of interactions among species,
including predation and competition. Effects of linear features on animal
movement have seen relatively little research in avian systems, despite
ample evidence of their effects in mammalian systems and that some types
of linear features, including both roads and transmission lines, are
substantial sources of mortality. Here, we used satellite telemetry
combined with step selection functions designed to explicitly incorporate
the energy landscape (el‐SSFs) to investigate the effects of linear
features and habitat on movements and space use of a large soaring bird,
the golden eagle Aquila chrysaetos, during migration. Our sample
consisted of 32 adult eagles tracked for 45 spring and 39 fall migrations
from 2014 to 2017. Fitted el‐SSFs indicated eagles had a strong general
preference for south‐facing slopes, where thermal uplift develops
predictably, and that these areas are likely important aspects of
migratory pathways. el‐SSFs also provided evidence that roads and
railroads affected movement during both spring and fall migrations, but
eagles selected areas near roads to a greater degree in spring compared to
fall and at higher latitudes compared to lower latitudes. During spring,
time spent near linear features often occurred during slower‐paced or
stopover movements, perhaps in part to access carrion produced by vehicle
collisions. Regardless of the behavioural mechanism of selection, use of
these features could expose eagles and other soaring species to elevated
risk via collision with vehicles and/or transmission lines. Linear
features have previously been documented to affect the ecology of
terrestrial species (e.g. large mammals) by modifying individuals'
movement patterns; our work shows that these effects on movement extend to
avian taxa.