Experienced divers don't just see more fish. They read the reef differently.
A dive trip planning and marine life identification tool built for divers who want to know the reef before they hit the water — and help protect it once they're in it.
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The Ocean Current Method
The 5-step cognitive process behind every drill in the arcade — how experienced divers actually turn a glimpse into an identification.
Methodology inspired by PlayFlyway.com — field skills for nature & wildlife enthusiasts.
Predict
Before you commit to an ID, state your confidence. Guess, think so, or sure — calibrating your instinct is the first skill, not an afterthought.
Detect
Scan the whole animal before naming it: overall shape, size relative to its surroundings, and where in the water column it sits.
Interpret
Read silhouette, color and markings, and swimming pattern together — no single cue tells the whole story on its own.
Differentiate
Rule out lookalikes and hazard-adjacent species before you commit to a call. This is where most misidentifications actually happen.
Commit
Make the call, then attribute the evidence that drove it. Reviewing your own reasoning is how calibration improves over time.
Our Mission
Spot the Reef exists to make divers better prepared and more reef-aware. Knowing what to expect — depth, temperature, visibility, hazards, and the species you're likely to encounter — makes for safer, more confident dives. And divers who can identify what they're looking at are divers who notice when something changes: bleaching, invasive species, declining populations. Preparation and conservation go hand in hand.
Powered by Citizen Science
The species you see in the Marine ID Guide come from real observations logged by divers, snorkelers, and naturalists around the world through iNaturalist. Research-grade iNaturalist observations feed into the Global Biodiversity Information Facility (GBIF), the same open network scientists use to track biodiversity worldwide. Every sighting in the field guide is a small piece of that larger, ongoing effort — and every dive you log with an identified species can be part of it too.
Support Spot the Reef
Spot the Reef is free to use, with no paywalls on identification, quizzes, or trip prep. If it's been useful to you, you can help keep it running with a small one-time or recurring contribution — or by using the affiliate gear and travel links on the Dive Site Recon page, which cost you nothing extra.
Buy me a coffeeOcean Safety & Eco-Diving
- Never touch marine life. Even a light touch can strip protective mucous coatings, damage coral tissue, or provoke a defensive response from a species that's more dangerous than it looks.
- Master your buoyancy. Good buoyancy control keeps fins, gauges, and knees away from fragile coral and silty bottoms that take years to recover once disturbed.
- Look, don't take. Leave shells, coral fragments, and anything else exactly where you found it.
- Dive within your limits. Respect your certification level, follow your dive computer, and always defer to local dive master guidance over anything you read here.