The study began when Benjamin Freeman found Louise Waterhouse’s older maps of mountain bird communities. Freeman and others used the hand-drawn maps and local knowledge to find and resurvey the original field sites on foot. They often started very early and sometimes walked in snow and cold. Most fieldwork happened in the birds’ breeding season from late May into June.
By comparing the two snapshots, the team found that temperatures have increased over 30 years but most bird populations did not decline. Many species became more common at higher elevations. Freeman said some species need help, and he named the Canada Jay as one that is struggling. The research can help focus conservation effort and is funded by the Packard Foundation.
Difficult words
- resurvey — to visit a place again and collect data
- map — a flat picture that shows placesmaps
- breeding season — time of year when animals make babies
- population — all the animals of one species in areapopulations
- elevation — height of land above sea levelelevations
- conservation — care and protection of nature and animals
Tip: hover, focus or tap highlighted words in the article to see quick definitions while you read or listen.
Discussion questions
- Would you walk on foot in cold weather early in the morning to do fieldwork? Why or why not?
- How can this research help conservation efforts?
- Do you know a bird species that is more common at higher places near you?
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