Setup: Raspberry Pi Zero 2W + USB webcam + Supabase (free tier) + 93 lines of Python that captures a 1280x720 frame every 60 seconds with retry logic for the Pi's flaky WiFi.
Analysis: Ran 1,500 images through Qwen 2.5 VL 7B via OpenRouter API. 996 tokens per image. Total cost: $0.37.
Results:
- 433 birds detected across 3 days (23.7% of frames) - Peak hour: 3 PM (86 birds), not dawn like I expected - Afternoon (12-5 PM) accounts for 70% of all activity - Day 3 had 6x more birds than Day 1 — Bird NPS of 100, they told the flock - Biggest frame: 5 sparrows simultaneously - Species mix: house sparrows, house finches, pigeons, one possible hawk
Hardware BOM: $80.23. Running for a year would cost ~$27 in API.
Page has the interactive dashboard, real captured images, and links to the code.