What do thousands of horseshoe crabs do when the evening tide is high, and the spring moon is full? Grab your flashlight to see a spawning so huge that people travel to view it from around the world.
The scene begins with male horseshoe crabs waiting along the water’s edge. As a female moves with the tide onto the beach, the male grabs her shell with his claws, hitching a ride on her shell. As she builds nests or leaves egg clusters along the beach, the male is pulled with her, fertilizing the eggs. Once the mating is complete, both head back to the water. Most of the action happens late into the evening, after 10 pm. Over multiple trips over multiple nights, one female can lay up to 88,000 eggs per year.
Let’s watch these living fossils ride the tide at Slaughter Beach in Delaware. We’ll learn about their behavior and how they contribute to the ecosystem of the Delaware Bay. The beach is known for having some of the highest counts of horseshoe crabs in the area, with over 60,000 in May 2022 and over 5,000 on the new and full moons in June 2022.
Our guide is Brad Stevens, Professor Emeritus and Distinguished Research Scientist at the University of Maryland Eastern Shore (UMES). Brad recorded a Zoom session for us last year, and we encourage you to check it out on our YouTube channel here: https://youtu.be/eOEM4uUEVK0?si=ey7mXWTQbmGTCqoB. This is an excellent introduction to horseshoe crab behavior and their important role in the Bay ecosystem. Dr. Stevens worked in Kodiak, Alaska, for over 20 years before coming to UMES, where he used scuba and underwater video to study fish, crabs, conch, and corals. He tells his graduate students, “Always study something you can eat.” Would that apply to a horseshoe crab?
Slaughter Beach is about a 2-hour drive from Baltimore. There is adequate parking and restrooms. Plan to stay up very late to see the most action. Google map link here:
https://maps.app.goo.gl/Uhvu5JULE4VVXg6BA. If you would rather stay the night than drive back late, hotels are plentiful in Milford.
Difficulty: Moderate with the possibility of cold conditions, definitely wet, and darkness
- Our meeting location can be found in your registration confirmation email when payment is completed.
- Watch for additional details in a welcome email sent a few days before the date.
- All participants must be pre-registered. If you are on the waitlist and show up to the event uninvited, you will not be allowed to participate.
- Children older than 10 years old are welcome to attend and must be registered as a guest of their adult.
- No more than two children per adult. Children must be able to listen and follow along with the group, and be aware of their surroundings to keep the animals safe.
- Heavy-duty flashlight with extra batteries. It may get wet.
- Wear clothes that may get wet. Bring extra clothes in case you get wet.
- Wear sturdy closed-toed shoes that can get wet. You do not want to step on a horseshoe crab’s spikey tail.
- A UV light can be fun – the crab eggs glow in the dark.
- You may leave at any time or stay as long as you like.
- Restrooms are available.
- Bring a first aid kit for your personal use.
- No pets, please.
All events are held rain or shine. If any event is cancelled due to severe weather, you will receive an email or text. If you do not receive a weather-related email, the trip will proceed as planned.
Payment and Cancellation Policy: Payment is due online at the time of registration. Cancellations made 14 or more days in advance of the event will receive a refund minus a 5% processing fee. Cancellations made within 14 days of the event will not receive a refund. Events and field trips with fees of $25 or less are non-refundable at any time unless canceled by NHSM. NHSM retains the right to update or change these requirements at any time.
For questions, please email Jayne at JAsh@marylandnature.org.
