Water flower in Prime Hook Creek

  

Horseshoe Crab Watch
2008


Last updated June 6, 2008

 

 

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Day One | Day Two | Day Three


Horseshoe crabs are prehistoric arthropods that have remained unchanged for 360 million years. In late May and early June, they come to the beaches of Delaware to lay their small, green eggs. A single female can lay 80,000 eggs!

The horseshoe crab spawn is something I've been wanting to see for years. In 2008, I decided it was finally time.
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Day One: Saturday, May 31, 2008

Norma and I set out bright and early at 0645 to beat the Bay Bridge traffic heading to the eastern shore. We were successful.

Our last Delaware kayaking trip was on August 5-7, 2006. This time we would return to a different part of the first state. Though we would have fun exploring, camping, biking, hiking, kayaking, and dining, our main goal was to see the horseshoe crab spawn.

The forecast called for
Showers and thunderstorms likely, mainly after noon. Some storms could be severe, with damaging winds, heavy rain, and frequent lightning. Mostly cloudy, with a high near 80. Breezy, with a south wind between 16 and 22 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Compared to Sunday and Monday, Saturday was expected to have the worst weather. Hence, I decided to make it a non-paddling day. We spent much of the day exploring Sussex County, looking for launch sites. Though I found some on Sunday and Monday, an overwhelming majority of the launch sites I found were on Saturday. By Monday, I found 11 new places to launch! The ones in the northern part of the county would be for a future trip.

When exploring, my ADC maps are priceless. For a weekend trip, they rank right up there with camera, global positioning system (GPS), wing paddle, and surf ski. But my Sussex County, Delaware ADC map had a few errors and failed to show quite a few of the boat ramps. This made exploring a bit challenging at times. But I guess I shouldn't expect too much. I was using the first edition map...it will surely improve over time.

Norma and I explored Slaughter Beach. See first photo at left. It isn't a tourist attraction like Ocean City. In fact, I didn't even see a place to eat. But there was plenty of public access all along Bay Avenue (road 204) with a public restroom on the south side, just north of Slaughter Beach Road (road 224). We walked the north side of the beach along with the south side of Milford Neck Wildlife Area/Preserve. At the wildlife area, the ground was a mix of sand and some soft organic material similar to peat moss. See second photo at left. I've never walked on ground like that before. We saw several dead horseshoe crabs (third photo) and some that were still alive. The ones that were alive were flipped upside down and starting to dehydrate in the hot sun (fourth photo). We flipped them right-side-up and carried them to the water. I'm guessing we saved about 15 in the hour we spent at Milford.

In addition to horseshoe crab, we saw something that resembled a necklace made of banana chips. See fifth photo at left. I originally thought it was some sort of bay vegetationand later leanred that it was a whelk egg case.

There were also some 4-6 inch long egg-shaped things all covered with grassy plants. See sixth photo at left. Norma peeled one open but it was just solid grassy stuff. No critters inside.

Cactus grew on the beach. See seventh photo at left. They weren't prickly. The things that should have been thorns were rubbery.

We found some nice shells including a 5 inch long conch.

Norma and I stopped at Cods Road over Slaughter Creek. We saw a three foot long northern water snake (eighth photo) and what we think was a muskrat fording the creek.

At Prime Hook National Wildlife Refuge, we walked the one mile Dike Trail, the half mile Boardwalk Loop (ninth photo), and part of another un-named trail. We found some interesting trees. See tenth photo at left.

Speaking of interesting, we spoke to a woman at the visitor center whose mind and memory were as sharp as a tack, despite the fact that she was born in 1927! She told us about her life in Delaware back during World War II. She also told us about the horseshoe crabs in the area. Two weeks prior to our visit, there was a really bad storm that wiped out several of them. Because of the number of horseshoe crabs that perished, the red knot birds that eat their eggs might not do so well this year on their migratory flight northward.

Prime Hook National Wildlife Refuge contains over 8000 acres of wetlands, including freshwater marsh, tidal marsh, and open water. The Refuge's 4200-acre freshwater march, one of the largest of its kind on the east coast, attracts tens of thousands of migratory waterfowl each fall. Thousands of shorebirds visit the same area in the spring and summer.
- from park sign

We continued looking for launch sites. Dark clouds rolled in then the severe storm predicted earlier hit. We sought refuge in a coffee shop in Milton but soon after we arrived, the power went out. Fortunately, the bad weather passed quickly. It was unusual that I was glad to be in a coffee shop rather than on the water.

Driving onto Lewes, we checked into Cape Henlopen State Park. After setting up our tent, we headed onto explore the 0.6 mile Seaside Nature Trail.

The trail took us to a beach on the Delaware Bay side of the park. The Delaware Bay hosts the largest population of horseshoe crabs in the world. There are only 4 species of horseshoe crab and the one we saw was the Atlantic (Limulus polyphemus). There were several dead crabs but also many that were alive. And since it was near high tide, we saw several come ashore to mate. See eleventh photo at left.
  • Each May and June, adult horseshoe crabs return from deeper waters to spawn, seeking beaches in bays and coves that are protected from surf. Peak spawning occurs on evening high tides during new and full moons.
  • During spawning, the horseshoe crabs form clusters along the edge of the water, with as many as 12 "satellite" males grouped around one female. Females burrow into the sand and lay masses of green eggs, which are then fertilized by the males around her.
  • Each female will return to the beach on successive tides, laying as many as 4-7 egg clusters with each tide. Each cluster, which incubates 5-8 inches below the surface, contains about 4000 eggs. A female typically lays about 25 egg clusters each year.
  • Fertilized eggs hatch in about 14 days.
  • - from a sign at the end of Fowler Beach Road (road 199) at Fowler Beach in Delaware

    Horseshoe crabs weren't the only critters that we saw around dusk. There was also a fox foraging for food around a picnic area. See twelfth photo at left.

    Unlike Slaughter Beach which had that thing that looked like banana chips on a string, we saw something that looked like tiny eggs on a string. See thirteenth photo at left. I believe they were horseshoe crab eggs.

    That evening, we explored some of historic Lewes and ate a nice meal at Jerry's Seafood on 108 Second Street.
    Click thumbnails to enlarge.










    Day Two: Sunday, June 1, 2008

    Norma and I were up bright and early at 0530. Our previous trip to Delaware taught us how strong the tide can be so we wanted to make sure we had the tide on our side today.

    After a yogurt, granola, and banana breakfast, we were off to Oyster Rocks. Here, we locked up our bicycles. Then we drove to Chandler Street in Milton, where we launched the Ocean Kayak Cabo in the Broadkill River.

    We launched just after 0800.

    I made some modifications to the Cabo since we last took it out. I made footwells out of PVC board then secured them with wellnuts. Unlike previous trips, we took the adjustable seats. Together, the footwells and seats ensured we had something secure to push against with our feet. Unfortunately, the high seats had a cup-like feel. They gave lots of support to the middle of our back and not enough for our lower back. I guess I've got more work to do.

    The upstream section of the Broadkill is very scenic. Lots of trees and no other boats. See first photo at left.

    Soon, we came to the Edward H. McCabe Preserve, owned and managed by the Nature Conservancy. We docked the boat then explored the Preserve trails on foot. Like the Broadkill, the trails were scenic and full of trees. We saw nobody...unless you count a turtle.

    Continuing onward, we stopped for lunch at a cove just west of Beaverdam Creek. There, we saw what I think was a muskrat swimming across the cove.

    Next, Norma and I paddled up Beaverdam Creek until we reached Brickyard Road. Paddling back downstream showed us just how strong the current was becoming.

    After crossing under Coastal Highway (road 14), the trees that bordered the river were replaced by grass. I don't know if the wind picked up or if the trees in the earlier part of our trip sheltered us but it seemed like we were catching a strong tailwind along with a strong downstream current. We were maintaining a 5 to 6 mph moving average which is pretty good for a slow boat. I would not have wanted to paddle that route 6 hours later with the tide moving in the opposite direction.

    The muddy shore was filled with nooks and crannies that housed fiddler crabs. They would scurry about as were paddled closer.

    After taking out at Oyster Rocks, we unlocked the bikes, locked up the boat, stored our gear in the hatch, secured the hatch with plastic ties, then commenced riding back to Milton.

    We took a little detour to eyeball a residential area. A little later, we stopped at what appeared to be an unidentified flying object (UFO). See second photo at left.

    After paddling 12.75 miles and biking 10 miles, Norma and I loaded up the bikes and began driving back to the Park. If it wasn't for her, I would have forgotten to retrieve my boat...actually, I would have eventually remembered but not until much later.

    At Cape Henlopen, we checked out the Seaside Nature Center. There were got to touch a horseshoe crab (as if we hadn't already been doing that) and see ray (or was it skate?) eggs. One of the workers told us about a horseshoe crab survey that would be occuring later that night, around high tide. We were welcome to participate.

    Our next stop was the beach. What makes Cape Henlopen State Park interesting is that one side is bordered by the Delaware Bay while the other side has the Atlantic Ocean. We headed to the ocean. After pulling two (lone star?) ticks out of Norma, we donned our wetsuits and played in the surf. I taught Norma how to catch a wave on the body board. This was her first time playing in the ocean waves.

    The tide rose quickly. Everything not on a sand dune got wet. Despite wearing wetsuits, I got extremely cold and began to shiver uncontrollably. It seems like that happened on our last camping trip too.

    After washing up, we went to the pier to participate in the horseshoe crab survey. There were about 20 people already there ready to gather data for the statisticians to use in monitoring the health of the crab population.

    Dark clouds, lightning, and thunder were moving in and the survey leader decided to cancel the event. Surveys take place over a few nights at the high tide near or at the full moon and new moon so if they canceled one survey, there would be others to fill in the gaps. But the leader told us quite a bit about the crab and answered questions. He mentioned that the horseshoe crab's blue copper-based blood (ours is iron-based) contains a clotting factor that detects gram-negative, disease-causing bacteria. It is so effective that the biomedical product derived from it, called LAL, is used for screening all injectable medicines and devices implanted in the human body to ensure they are free from bacterial contamination.

    Norma and I walked along the beach, despite the ominous weather. As it turned out, the storm passed by and only dropped a few sprinkles on us. We saw several crabs coming ashore to breed. Again, we flipped over the ones that were turned upside down.
  • Third photo: Me with horseshoe crabs.
  • Fourth photo: Pair of horseshoe crabs.
  • Fifth photo: Orgy of horseshoe crabs.
  • Sixth photo: Horseshoe crabs at sunset.
  • Seventh photo: Norma with horseshoe crabs at sunset.
  • Eighth photo: Norma and me on beach.
  • Ninth photo: Delaware Bay sunset.

  • We caught a late dinner in Lewes at Grotto Pizza Grand Slam then called it a night.
    Click thumbnails to enlarge.
















    Day Three: Monday, June 2, 2008

    After a cereal and fruit breakfast, we biked out to the Point, which is the peninsula that separates the Delaware Bay from the Atlantic Ocean. We walked along the beach near this area and right-side-upped a few more horseshoe crabs. See Norma in action in the first photo at left. An 18 inch wide skate washed ashore and died before we arrived (second photo). Some of its body felt prickly but the most interesting part was its mouth (third photo). It had several rows of small teeth, one behind the other. It felt like a file.

    We rode south, paralled to the Atlantic shore. We stopped at the Fort Miles Historic Area where we caught a nice view of the shoreline. See fourth photo at left. Then we biked past some old barracks and some World War II artillery pieces. To direct the artillery, several observations towers were constructed. We climbed one of them. See fifth photo at left.
    Built from 1939 to 1942, the 11 concrete observation towers along Delaware's coast were built to protect the shores during World War II. The were made to last about 20 years but are still standing to this day. The towers were the eyes for the guns of Fort Miles, located in Cape Henlopen State Park. Abandoned since the early 1960s, these sentinels once stood guard against German ships.
    - taken from sign at obervation tower in Cape Henlopen State Park

    Next, we walked the 1.7 mile loop Pinelands Nature Trail. We saw a sandy frog (sixth photo) and some flowers that smelled like roses (seventh photo). Norma said the two are related.

    We rode back to the campsite then loaded up. Our gear was nice and dry.

    Our original plan was to launch from Coastal Highway (road 14) at Old Mill Creek then take out at Oyster Rocks. Unfortunately, the bridge over Old Mill Creek was not a good place to put in. Actually that is an understatement. Hence, I came up with plan B.

    At Prime Hook National Wildlife Refuge, we picked up a pamphlet describing a 7 mile long canoe trail. From the takeout at the Refuge, the route didn't look particularly interesting. Too open and grassy. But our friend Stacy spoke very highly of this area so I figured we'd give it a go because she's never wrong.

    We left our bikes at the Refuge Headquarters then drove to Brumbley Family Park. The launch area was a creek only about 12 feet wide! If it wasn't a designated canoe trail, I would have had my hesitations about this route.

    Soon, the creek opened up into a less claustrophic waterway. What is nice about this area is that the water is fresh. Thus, we can launch anytime without having to worry about the tide. Not only is the water fresh, but in the western parts, it is also very clear. It was a nice change from the murky and brackish Chesapeake Bay water with which I am more familiar.

    After a short distance, we passed a couple of other paddlers. They would be the only other boaters we would see on the water that day. Then we came to a lagoon filled with lilypads and water flowers. The place was in full bloom. I've never seen so many water flowers before. See eighth and ninth photos at left. Also see the photo at the top left corner of this page.

    Turtles were abundant. Far too many to count. But here's one that wasn't too camera shy. See tenth photo.

    We counted 5 beaver lodges. Unfortunately, we saw no beavers.

    The water trail was mostly narrow and tree-lined. I often mention the upper Pocomoke River as being the most scenic area to paddle but I think the western half of Primehook Creek might be equally as beautiful...and that says a lot!

    We saw a large carp wading in a shallow area. It took awhile before we figured out what it was and it also took awhile for it to realize we were there but once it did, it quickly disappeared.

    The creek opened up a bit to several dead trees. Not sure what killed them.

    Next, the scenery changed to grasslands. I found it interesting how the grass was one color near the base and a different color near the top. See eleventh photo at left.

    I didn't check to see when the gate closed at the Refuge so we paddled faster. I didn't want to have to carry my boat a mile to the exit. We found out later that they didn't close up until after dusk so we were plenty safe.

    Norma and I unlocked the bikes, locked up the boat, then rode back to the car. We saw several pretty flowers in big fields. See twelfth and thirteenth photos at left.

    After a short 4 mile ride back to the car, we headed out to Fowler Beach, scouting more launch sites along the way.

    On Fowler Beach Road (road 199) near Slaughter Creek, we saw hundreds of dead horseshoe crab. See fourteenth photo at left. They were about a quarter mile from the Bay. Perhaps the storm two weeks prior rose water levels enough so that they went ashore there. If that is where they laid their eggs, their offspring would have no chance since it was now dry.

    We spotted a pretty big turtle in this area (fifteenth photo).

    At Fowler Beach, we spotted sign just overflowing with information about the horseshoe crab.
  • In 2006, Prime Hook National Wildlife Refuge partnered with the Ecological Research and Development Group to establish Fowler Beach as a horseshoe crab sanctuary.
  • The horseshoe crab was designated as Delaware's official marine animal on June 25, 2002.
  • Horseshoe crabs typically live 20 years and reach sexual maturity at about age 10.
  • As the horseshoe crab grows, it must molt and shed its shell. After the first year, it is about a half inch wide. Only about 30 out of a million larvae live to see their first birthday.
  • As the horseshoe crab ages, it moves into deeper waters to find a larger food supply. These pre-adults molt once a year until they reach sexual maturity. Then they begin their annual spring migration to the spawning beaches to renew their species.
  • The compound lateral eye of the horseshoe crab can see up to 5 feet away, but at night, the sensitivity of the eyes increases one-million-fold.
  • You can distinguish a male from a female by looking at the pedipalps. The pedipalps are the first pair of walking legs. On a female, they resemble the other 8 legs but on a male, the end of the leg is modified to form a grasping claw, which the male uses to latch on to the female in spawning.

  • On the drive home, I pondered how perfectly evolved the horseshoe crab must be to have remained almost unchanged for the last 360 million years. Hopefully, our immature species won't do anything to bring about their downfall anytime soon.
    Click thumbnails to enlarge.


    Norma and I managed to fit about four days of activities into three. We did a lot and learned even more. We must have rescued at least three dozen horseshoe crabs. We saw probably over 200 living crabs! However, the areas we searched were not their primary breeding grounds. Next time, we should check between Port Mahon (just east of Dover) and Bowers Beach (at the mouth of the Murderkill River). This along with paddling at Bombay Hook National Wildlife Refuge should make for a nice trip.

    Could another horseshoe crab trip top this one? It is hard to say...but we'll probably try...and have lots of fun doing so.