As of Jun 15, 2026, 11:43 PM, out of season, returns ~May. Earth Exhibit tracks the live conditions and flags it the moment it is on.
Each spring along the Delaware Bay shoreline, hundreds of thousands of Atlantic horseshoe crabs come ashore to spawn.
Their eggs provide a critical food pulse that allows red knots (Calidris canutus rufa) to refuel during a long-distance migration.
Peak activity is tightly linked to spring high tides and moon phase in late May.
Where to see it
A taste of where to see it. The full map, exact coordinates and the best timing for each spot live in the app.
| Viewing spots |
|---|
| Reeds Beach (Lower Township / Cape May) |
| Heislerville Wildlife Management Area / Fortescue shoreline |
| + 1 more spot, with exact coordinates and timing, in the app → |
This is the short version
This page shows a taste. The app has the full list of where to see this, the exact timing, and live conditions for 1,000+ natural phenomena worldwide, so you know the moment one is genuinely worth the trip.