MILTON –– With the unofficial arrival of summer this weekend, the annual arrival of horseshoe crabs and shorebirds is well underway along the Delaware coast and will be celebrated this weekend at the 13th Annual Horseshoe Crab & Shorebird Festival.

The festival, held at Prime Hook National Wildlife Refuge, 11978 Turkle Pond Road in Milton, will begin tonight at 5 with a horseshoe crab flip along Broadkill Beach.

As the horseshoe crabs come onto the beach for their ritual spawning, they may be flipped on their backs by rough waters, leaving them stranded. Hundreds of thousands of horseshoe crabs are estimated to die this way every year.

Just Flip ’Em, a statewide initiative to literally get the crabs back on their feet, reports that flipping the animals off their backs isn’t dangerous. Horseshoe crabs don’t bite or sting and although they do have claws, they are not sharp. It is important to flip them by touching the sides of their shells, not their tails, which can be easily damaged.

Anyone who wishes to participate in tonight’s flip is encouraged to bring a flashlight and weather- and beach-appropriate attire.

Nature experts will lead the walk down the beach to teach flippers more about horseshoe crabs and to answer any questions about the unique creatures.

Saturday’s festivities start at 10 a.m. at Prime Hook where special activities will be happening throughout the day such as guided canoe trips, guided trail walks and opportunities to learn about and touch horseshoe crabs.

Over at Memorial Park –– behind the library –– in Milton during the same time, a nature tent will be the center of activities with exhibits from Prime Hook about the local environment and animals and how to preserve and protect them both.

Kids will have the chance to participate in a scavenger hunt and to paint and decorate horseshoe crab shells in a tent dedicated to art with nature.

There will be also be music, food and arts and craft vendors in Memorial Park until the festivities wrap up around 4 p.m.

For additional information visit www.historicmilton.com/events.