Wildlife · Sheltered bay beaches (Accabonac, Napeague, Peconic shores)
Atlantic Horseshoe Crab
Limulus polyphemus
A living fossil older than the dinosaurs. During May and June, adults congregate along sheltered bay shorelines to spawn, timed to the highest tides around the full and new moons, their eggs feed migrating shorebirds like the Red Knot. Seatuck runs community monitoring nights and a sighting tracker.
Best months
JanFebMarAprMayJunJulAugSepOctNovDec
- Best time of day
- Evening high tide
- How to see
- Walk a calm bay beach at the evening high tide around the May-June full or new moon and scan the waterline for spawning pairs. Count, don't touch; report sightings to Seatuck's Horseshoe Crab Tracker.
- Who films them
- @seatuckenvironmentalruns the programs
- @ccesuffolkhorseshoe crab monitoring
- Age
- All ages
- Accessibility
- Beach walking
- Responsible viewing
- Observe from the waterline and let spawning pairs be. Never pick a crab up by its tail.
- Weather / sea state
- Calm bay conditions; spawning peaks on the monthly spring tides.