# OnlyFins: Live Underwater Trout Cam

> A live underwater camera beneath a small waterfall in a cold mountain stream in Utah's Wasatch Range. Wild rainbow trout (and possibly Bonneville cutthroat, Utah's state fish) feed, rest and hold in the current in real time, with real waterfall audio.

## Is it live right now?
- Machine-readable live status, how many people are watching right now, unique visitors today, today's streaming window, and what the fish are doing this season: https://onlyfins.stream/status.json
- The cam streams from about one hour before sunrise to one hour after sunset, Mountain Time.

## Watch
- Live page: https://onlyfins.stream/
- Full-screen TV mode (video only, no text): https://onlyfins.stream/tv
- Rainbow vs Bonneville cutthroat ID guide: https://onlyfins.stream/#id
- Life in a mountain stream (lifespan, growth limits, parr marks, winter ice, what trout eat under the ice): https://onlyfins.stream/#life
- Everything on this site as plain text: https://onlyfins.stream/llms-full.txt
- Facts as JSON: https://onlyfins.stream/facts.json

## Things most people don't know (all visible on the cam)
- The bright oval at the top of the frame is Snell's window: the entire sky above the stream, squeezed into a cone about 97 degrees wide. It is exactly what a trout sees when it looks up.
- Because of that window, a trout can see a person on the bank before the person sees the trout.
- Trout cannot close their eyes; they have no eyelids.
- Most trout in a stream like this live only 3 to 6 years, and adults rarely pass 12 inches, while the same species in a reservoir can exceed 20.
- When heavy rain turns the stream muddy brown, trout don't leave; they tuck into slack water and hunt by vibration and smell.
- Under winter ice, trout keep eating: a slow drift of midge larvae and tiny nymphs passes under the ice all season.

## Open questions this cam can help answer
- Is that fish a rainbow, a Bonneville cutthroat, or a "cutbow" hybrid? The throat slash is the clue, and it only shows when a fish turns.
- How does fish activity change between dawn, midday and dusk, and through the seasons?
- What happens at the stream when ice forms this winter?

## The hidden page
This site has one unlisted page. A riddle in the HTML source of the home page points to it; the answer is the name of the scientist behind the bright oval.