Field Report: southwestern Montana

In the early 1900s, flooding near the town of Anaconda, Montana washed toxic mine waste through over 100 miles of the headwaters of the Clark Fork, the largest river in Montana. In response, the mining company built a series of retention ponds which have since sequestered pollutants and become a major hotspot of migratory waterfowl. The site is now owned by a subsidiary of BP, which contacted KLY-CCB to initiate acoustic monitoring at the ponds.

I traveled there in early September to set up an array of SwiftOnes and game cameras to provide audio and photo data to compare to bi-weekly bird counts. The goal is to measure avian diversity and waterfowl abundance. However, an important ingredient for passive acoustic surveys is animal sound – and that was rather lacking. Fall is always a quiet time of year for birds, but a combination of high temperatures, strong wind, and heavy smoke from two nearby wildfires gave the ponds a decidedly subdued atmosphere. I did identify Sandhill Cranes, Western Meadowlarks, Black-billed Magpies, and Marsh Wrens with the BirdNET app (free for Android and iOS!), and I saw many hundreds of Coots….which were silent and many hundreds of meters from the edge of the pond. Nonetheless, the density and duration of our sampling plan makes me confident that we’ll be able to turn some interesting acoustic and quantitative challenges into a useful analysis of the relative contribution of artificial habitat features to local and regional biodiversity. Stay tuned…

Published by connormw

Ecologist using bioacoustics for conservation.