A microphone sits beside a creek in western Washington and listens around the clock. Software identifies bird and frog calls as they happen, and this site is rebuilt from that log every quarter hour: a field guide to one small patch of forest, written by the forest itself.
Sound is analysed by two open models, BirdNET (Cornell Lab of Ornithology) and Google's Perch, running on a small computer at the house through BirdNET-Go. A species is listed only when the models are at least 70% sure of a call at least 3 times, or 90% sure once; clips are published at 85% or better. The seasonal curves come from BirdNET's range model, asked week by week for this location. Weather is from a station beside the microphone, via Home Assistant.
Nobody checks these identifications by hand, so some are wrong, especially for species with similar calls or few detections. Counts are "calls identified", not birds: one chatty wren can rack up dozens. The field notes were drafted by an AI assistant from general ornithological knowledge and may contain errors; corrections are welcome.
The illustrations are public-domain natural-history plates: John James Audubon's Birds of America (1827–38), Louis Agassiz Fuertes' work for Bird-Lore and the state bird books of New York and California, Allan Brooks' plates for Dawson's Birds of Washington (1909), J. G. Keulemans, Naumann, Chester A. Reed's pocket Bird Guide (1906), Mary Cynthia Dickerson's The Frog Book (1906) and others, via Wikimedia Commons. Each plate links to its source. Encyclopedia summaries are from Wikipedia (CC BY-SA). No cookies, no tracking.