Fly me to the Moon, but stop in New Jersey on the way: the incredible migrating Red Knot

Reports are that Moonbird has once again landed in New Jersey to enjoy a hearty meal on the beach in Cape May County.

Ivan gets a good look at Moonbird, the larger-than-life Red Knot
(photo was not taken in New Jersey, but I couldn't resist.)

Lest you think an extraterrestrial avian creature was discovered on the Delaware Bayshore, let me explain. Moonbird is one of a dwindling number of Red Knots, robin-sized shorebirds that visit us enroute from their winter havens in coastal Argentina and Chile up to their summer nesting spots in Arctic reaches of Canada. Estimates are that as few as 25,000 individuals remain, and scientists have been studying them for several years, tagging several of the birds to track their routes. Carrying the number B95 on his leg band, Moonbird got his nickname for the mind-boggling distance he's flown so far in his life. Over the 19 years since he was banded near Tierra del Fuego, he's traveled a distance equaling the trip from the Earth to the moon, and halfway back.

Ivan and I headed to Reed's Beach last Saturday in the hopes of finding a few Red Knots and maybe Moonbird himself. It's about the right time for them to land along the bayshore, about two-thirds of the way into a 9300 mile trek that's among the longest for any migrating species. During that kind of trip, they need a good refueling stop, and nature's ingenious scheduling accommodates well. As I mentioned in my last post, it's horseshoe crab mating season, and Red Knots are prodigious eaters of the eggs the helmeted arthropods lay on our beaches. By the time they leave for the Arctic, they'll have doubled their weight.

The endangered shorebird area at Reed's Beach.
Note light development to the left of the sign.

Reed's Beach is a smallish community, with maybe two dozen bungalows and a marina that serves recreational fishing boats up to 36 feet. Once you hit the end of the road, a walk along the jetty brings you to the bayshore. The beach is currently marked off with string and signs warning beach walkers not to stroll any farther during migratory shorebird feeding season, which is May 7 through June 7 in 2014.

Relegated to a small area, our view of the birds wasn't all that great. Though Laughing Gulls were in abundance nearby, only a few Sanderlings were visible by naked eye. Several horseshoe crabs were stranded on the beach, overturned by waves and helpless, but we couldn't cross the line to help them, not without harassing the birds.

After Ivan got the viewing scope, sighting became a bit easier, but still not optimal. A cluster of Red Knots was feeding far down the beach with a few Ruddy Turnstones, but we were really hoping for a much better look. This was my first exposure to real, live Red Knots, and I definitely wanted the chance to appreciate them in more detail. After having heard so much about the spectacle of their migration, I wasn't going to let one small sighting stand as my introduction.

Our luck was a bit better at Cook's Beach, just to the south of Reed's, where we found a small gathering of birders fixated at a spot a couple hundred yards up the shoreline. A sizeable cluster of Red Knots was enjoying their sand-bound feast, their brick-colored necks and breasts differentiating them from the Turnstones milling about with them. Ivan got the scope out for a closer look and estimated that a couple hundred of them were mixed in with the other species pecking away for their lunches. To this uneducated eye, they looked healthy and as eager to eat as ravenous passengers at an all-you-can-eat cruise ship buffet.

The Delaware Bayshore, as seen from Cook's Beach.
Houses on Reed's Beach are barely visible to the left of center.

We agreed: anything else we'd see for the rest of the day would be a bonus. New Jersey was doing its part, at least for these little guys, in sustaining and hopefully encouraging the growth in Red Knot numbers. What percentage of the total population was represented by the large group we'd seen? Small, we hoped, but the numbers aren't likely to be known for a while.

When you stand on the beach of the Delaware Bayshore, you can't help but appreciate the difference between it and, say, Long Beach Island. Sparse development along the beach leaves sufficient room for nature to exist, grow and thrive, whether it's migrating shorebirds, spawning crabs, or the gulls that wheel and laugh as they navigate the winds. Dunes are covered in grass, backed up by marshes that obscure all manners and shapes of life. And it's important for people, too: a quiet beach is a wonderful place to get reacquainted with the natural rhythms of life, and to just be. It shows us what's possible when we leave a portion of our shoreline to evolve on its own, rather than focusing on developing every last inch for human use.

After all, Red Knots travel thousands of miles to get to our undeveloped beaches. Could they know something we don't?

Getting crabby on Raritan Bay

I have a lot of respect for horseshoe crabs, in a "prehistoric creature that fascinates me" kind of way. They're survivors, having roamed the ocean floor for at least 300 million years. As other species have evolved and others have gone extinct, these helmet-shelled arthropods have largely stayed the same and managed to survive.

To be honest, though, they kind of freak me out. They're not the most attractive creatures out there, and, well, they're creepy. Most of the time, the only onshore sign of them is their molted shells, but in the spring, they're very active. Coming up the beach and out of the water, they lay and fertilize their eggs in damp sand, looking like some sort of automated armored toy as they move. I can appreciate their efforts, as their eggs play an important role in the larger ecosystem. After the crabs spawn and return to the water, the endangered Red Knot and other migratory shorebirds feed on them, regaining energy they need to continue their treks to breeding grounds far to the north. The remaining fertilized eggs develop into larvae and then baby horseshoe crabs, continuing the cycle of life.

The other day, I was just about done with a visit to Sandy Hook when I decided to check out the bayside beaches toward the south end of the hook. Out beyond the grassy dunes, I discovered nearly a dozen stranded horseshoe crabs, laying on their backs. They'd apparently been rolled over by the waves lapping up against the beach.

Since they were larger, I assumed them to be females, which made their survival all the more important. As the Bayshore Regional Watershed Council has discovered through their survey of Raritan and Sandy Hook Bays, the ratio of male to female horseshoe crabs in those waters is seriously out of whack. Where a natural ratio is about five to 10 males for every female, the bay region's population is about 20 to one. The issue becomes even more critical when you consider that they generally don't mature as adults until the age of 12, leaving them with about six years of fertility before they die at around age 18.

Scientists aren't sure what's causing the disparity in the genders, though the theory is that humans are playing a role. It's illegal to harvest horseshoe crabs in New Jersey, but it isn't in New York, where individuals can capture up to five a day for personal use. Egg-bearing females are especially prized as bait for eel and whelk fishing. Considering that Staten Island has a considerable shoreline on Raritan Bay, the answer may be right there.

As I was standing on the beach at Sandy Hook, I knew nothing about the troubling male-female ratio, just that the individuals stranded there clearly needed help. While there was a small chance of them being righted eventually by the gentle waves, it was more likely that they'd be picked at by gulls. Despite my squeamishness, I figured I had to be the one to turn them over, but there was no way I was going to pick them up. Nudging them over with my booted toe didn't seem right either, so I looked for a stick to do the trick. Fortunately a good sized driftwood branch was sitting on the beach nearby, perfectly bent to provide the right amount of leverage.

The first crab I approached was still wriggling her legs, apparently trying to build up enough momentum to roll over. Using the branch, I gently rolled her upright, and she rapidly walked back into the approaching waves. The next one wasn't as animated, but her book gills were panting, showing signs of life. She flipped over easily with a little help and was on her way. Another had stuck her spiny tail straight up, perhaps attempting to use it to right herself with no success. She was breathing, too, and responded well once I got her right-side up.

It looked as if I'd gotten there in time to help out all of the beached horseshoe crabs -- every one of them made her way back into the water after she got back on her feet.

I share this story not for any kind of praise but to share a simple way that we all can make a positive impact on the survival of horseshoe crabs and, by extension, endangered shorebirds. If you're on the beach and you see an overturned horseshoe crab, don't assume it's a molted shell or already dead. Check to see if it's alive (the moving gills are a good indicator). Then carefully flip it over by the shell, avoiding the scratchy, pointy tail. And remember: though it may look creepy, it's harmless. It's just a survivor of another age who's continuing to keep our ecosystem alive.

Ancient history renews itself on Raritan Bay

Usually I'm pretty single-minded when I'm traveling to or from Sandy Hook: it's a non-stop trip from home to the Hook, or vice versa, interrupted only by a stop for gas or maybe a custard cone. Yesterday, however, Ivan had other ideas as we made our way home after a productive birding excursion. 

"Let's stop on the bay," he said. "There's some good shorebird habitat there, and maybe we'll run into something else." 

"Something else" is usually a historic spot or a notable sign or something. This time it wasn't. Once we parked the car near a newish townhouse development, Ivan led the way along a sandy dirt path until we reached the waterline. On one side was the bay, with a nice tract of spartina being flooded by the incoming tide. On the other was the mouth of a small creek, edged by a dirt/sand mixture of shoreline. I was a bit birded out for the day, so I focused on what was moving around in the water. There was plenty to watch!

We'd arrived just in time for the start of the daily horseshoe crab spawning. In a routine that's gone on for more than 500 million years, the females glide up to the area between low and high-water levels to lay their eggs, followed by a host of males that fertilize them. Check out the brief video I recorded, showing how quickly the seemingly lumbering animals move to lay their eggs. (You may want to shield the children, as there is graphic arthropod mating action going on here.)

One mistake I made on the narration: horseshoe crabs aren't as plentiful as we need or would like due to overharvesting. They're actually quite popular for use as bait in the eel and conch fishing industries, plus their blood has certain benefits for use in medicines for humans. While they can be effectively bled and then returned to their customary habitat, the bleeding process has a horseshoe crab mortality rate of 10 to 15 percent.

Raritan Bay shorebirds will likely enjoy some of the eggs we saw being laid, but the acute need for horseshoe crab spawn is on the shores of Delaware Bay. Hundreds of thousands of migrant birds, including the threatened red knot, customarily land on the beaches looking for their first meal after a long journey. Without horseshoe crab eggs to count on, it's likely that many of them would die of starvation. Thus, organizations like New Jersey Audubon have been sounding the call for conservation and protection of these prehistoric animals. They may not look especially attractive, but they're a crucial link in our ecosystem.

If you happen to be on the beach around high tide, keep an eye out for these ancient helmet-shaped creatures. You'll get a biology lesson you won't soon forget. I know I won't.