Person:
Mills, Alexander M.

Profile Picture
Email Address
Affiliation
ORCID
Birth Date
Job Title
Last Name
Mills
First Name
Alexander M.
Creator of
Editor of
Reviewer of
Copyright Holder of
Data Contributor of
Funder of
Translator of
Other Contributor of

Filters

2017 - 201912020 - 20231
Reset filters

Settings

Search Results

Now showing 1 - 2 of 2
  • No Thumbnail Available
    Data package
    Data from: Urbanization and artificial light at night reduce the functional connectivity of migratory aerial habitat
    (2023-05-05) Korpach, Alicia M.; Garroway, Colin J.; Mills, Alexander M.; von Zuben, Valerie; Davy, Christina M.; Fraser, Kevin C.
    Flying animals use aerial habitats to forage, communicate and travel. However, human activities that fragment aerial habitat with built structures, noise, and chemical or light pollution, may limit the ability of wildlife to use airspace efficiently. Applying landscape connectivity theory to aerial habitats could reveal how long-distance migrants respond to sources of aerial habitat fragmentation along their migratory routes. Artificial light at night is a major component of urbanization that fragments dark skies across North America. Attraction of nocturnal migrants to urban light is well documented, but species-specific responses, especially throughout a full migration from breeding to wintering grounds, are not. We tested hypotheses about long-distance migratory movements in relation to artificial light using a highly nocturnal, Nearctic-Neotropical avian migrant (Eastern whip-poor-will Antrostomus vociferus). We applied a resource selection framework at multiple spatial scales to explore whether GPS-tracked birds (n = 10) responded to urbanization in general, or artificial light specifically, during migratory flights. We found little evidence of attraction to artificial light during nocturnal flights. Artificial light and urbanization were highly correlated and difficult to disentangle, but the birds generally avoided urban areas and selected dark-connected skies for travel. Migratory stopovers (locations where GPS-tracked birds (n = 20) paused for at least one night), were located almost exclusively in dark, rural areas. Our results illustrate that considering how nocturnal aerial migrants respond to both aerial and terrestrial habitat elements can improve our understanding of what may facilitate their long-distance movements.
  • No Thumbnail Available
    Data package
    Data from: Tracking the migration of a nocturnal aerial insectivore in the Americas
    (2017-04-07) English, Philina A.; Mills, Alexander M.; Cadman, Michael D.; Heagy, Audrey E.; Rand, Greg J.; Green, David J.; Nocera, Joseph J.
    Background: Populations of Eastern Whip-poor-will (Antrostomus vociferous) appear to be declining range-wide. While this could be associated with habitat loss, declines in populations of many other species of migratory aerial insectivores suggest that changes in insect availability and/or an increase in the costs of migration could also be important factors. Due to their quiet, nocturnal habits during the non-breeding season, little is known about whip-poor-will migration and wintering locations, or the extent to which different breeding populations share risks related to non-breeding conditions. Results: We tracked 20 males and 2 females breeding in four regions of Canada using geolocators. Wintering locations ranged from the gulf coast of central Mexico to Costa Rica. Individuals from the northern-most breeding site and females tended to winter furthest south, although east-west connectivity was low. Four individuals appeared to cross the Gulf of Mexico either in spring or autumn. On southward migration, most individuals interrupted migration for periods of up to 15 days north of the Gulf, regardless of their subsequent route. Fewer individuals showed signs of a stopover in spring. Conclusions: Use of the southeastern United States for migratory stopover and a concentration of wintering locations in Guatemala and neighbouring Mexican provinces suggest that both of these regions should be considered potentially important for Canadian whip-poor-wills. This species shows some evidence of both "leapfrog" and sex-differential migration, suggesting that individuals in more northern parts of their breeding range could have higher migratory costs.