Posts Tagged 'horseshoe crab'

Horseshoe Moon

Limulus polyphemusHorseshoe Crabs (Limulus polyphemus) mating on the shores of Jamaica Bay. It was the day after the full Moon, when the high tide lets them get farther up the beach, where they deposit their eggs.Limulus polyphemusI have written much about these amazing non-crabs and how important they are to our health.

I saw a headline the other day about how nobody picks carrion beetles, worms, slugs, & etc. as their “spirit animal,” which is a pity. Plenty of people owe their lives to Horseshoe Crabs and have no idea that they do so. Leucophaeus atricillaOther living creatures depend on Horseshoes as well, but in a different way. Laughing Gulls (Leucophaeus atricilla) are one of the bird species that gorge on Horseshoe eggs this time of year.

The Narrowest Edge

“We so easily settle for the diminished world around us, a world that, in terms of the richness and abundance of plant and animal life, may be a mere 10 percent of what once was. Unaware of what we have lost, we can’t imagine what we might restore, and instead, we argue over how many of the scraps we might still take.”TheNarrowEdge

When M and I were walking along the Northumberland coast last June, we came across a flimsy barrier cutting across the beach at Long Nanny. It was the beginning of nesting season and the beach was closed. We were wondering how to get around to the other side when a ranger emerged from the dunes. She told us we could actually pass right along the water’s edge. She also offered us a scope view of the Little Tern (Sternula albifrons) and Ringed Plover (Charadrius hiaticula) nesting there. The Little Tern in particular is now rare, and needs to be protected from blundering beach-goers, unleashed dogs, ATVs and other vehicles, as well as egg stealers (a rather British pathology).

Fencing and explanatory signs in New Jersey, Deborah Cramer tells us, are fairly effective, but those who heed the barriers the least are joggers and dog walkers. (I’m not surprised: narcissism seems to run high in these cohorts: their “rights,” as they will argue, trump all others.) On our coast, both the beach-nesting Piping Plover and long-distance Red Knot feeding on beaches are in dire straits. Their remarkable evolutionary adoptions aren’t much of a match for the rapid disruptions we cause.

Cramer, quoted at the head, is author of The Narrow Edge: A Tiny Bird, An Ancient Crab & An Epic Journey. The bird is the Red Knot, Calidris canutus, specifically the rufa lineage which migrates along the Eastern shore of the U.S., one of six lineages for the species. The “ancient crab” is the Horseshoe, which actually isn’t a crab at all, but rather akin to spiders and mites. Its ancestors go back nearly half a billion years, marking it one of the great survivors in a world in which 99.9% of all life forms no longer exist anymore. Species come and species go, nothing new there, but what is new is the human cause of all these extinctions and the radical simplification of the world. We’re supposed to be the moral animals, after all.

This is a wide-ranging book, like C. canutus rufa itself, from Tierra del Fuego to Arctic Canada, with stops along the way. Yes, it concentrates on one bird doing badly in the Antropocene, but there are so many ramifications here. Horseshoe Crabs were once turned into fertilizer by the millions, now they’re chopped up for bait and bled for medicine (few people realize that drugs and vaccines, IVs, pacemakers, stents, catheters, etc. are tested for bacteria with an extract made from the blue blood of Horseshoe Crabs: if you’ve been in a hospital since 1985, you can thank the Horseshoes for making sure you left alive.)

The radical transformation of the Arctic is another theme here. Red Knots and many other birds nest in the far north, where the radical heating is creating havoc in all sorts of ways: less nutritious food for seabirds, far too many mosquitos for nestlings, Polar Bears ravaging nesting areas because they can’t find enough ice and hence seals to eat. These are only some of the factors; the complicated intersections of all these things, the wonder of the world, are fraying and shredding in endless ways now. We’re simplifying these webs and cascades of life to an alarming degree. Nothing good is going to come of it, and horrors like species-jumping viruses are already roaring out of the rents and tears.

Cramer tries to be optimistic, but the weight of it all is too much for that. Still, we live, we read: this is very much worth reading if you, like me, think knowledge is important, however impotent.

Along the Shore


Life Along The Delaware Bay

I didn’t make it to the beach to witness the annual rites of spring of the Horseshoe Crabs (Limulus polyphemus). But I did manage a virtual trip with this beautiful book. Life Along The Delaware: Cape May, Gateway to a Million Shorebirds by Niles, Burger, and Dey, with photography by van de Kam, was published by Rutgers University Press last year. It’s a coffee table book with luscious photographs, but also one with a scientific bent. Indeed, even a point. The Bay is one of the most important ecosystems on the East Coast, but isn’t nearly as well-known as the Chesapeake. It’s especially important for shorebirds in migration, those epic flights to and from breeding grounds in Arctic Canada. For at least since the last ice age, this migration has coincided with the annual Horseshoe Crab breeding season. Massive amounts of Horseshoe eggs fed these long distance migrants, providing a vital half-way point. After more than a century of slaughtering Horseshoes for fertilizer, bait, and medicine, there are now many less Horseshoe crabs. Hence, less birds. A subspecies of Red Knot (Calidris canutus) in particular has been hard hit. These birds are known to fly six days straight (songbirds migrate during the evenings only, resting and eating during the day); indeed, before starting from Patagonia, Red Knots shrink their digestive systems to lessen their weight (mirroring the ability of birds to shrink their gonads once breeding season is over). The easily digested, protein-rich Horseshoe eggs are vital to the survival of the Red Knots. This is the main story told in this book, but it’s not the only one. It’s thoughtful, up-to-date, and, as noted, extremely well-illustrated.

Highlights of past Horseshoe Crab posts
Horseshoe Moon
Horseshoe Crabs

Two punks from Bergen Beach were recently busted for poaching horseshoes from Jamaica Bay. Telsons should to driven into their gonads. They were caught pretty much by accident, by NYPD detectives testing night-vision gear in a helicopter. Park Police have a boat, but it remains tied to the dock.

First Horseshoe?

We approach the first anniversary of my now constant companion, the distinguishing identifiable feature of my corpus, my horseshoe crab tattoo. So I was most pleased to notice this detail in the book, Natural Histories, I reviewed in my last post. In 1590, Theodor de Bry’s opus America presented some of the first images of the New World to the Old. Bry (1528-1598) and his sons made engravings from the paintings of John White (c. 1540-1593), who was appointed Governor of Roanoke Colony in 1587. One of these shows some of the original (native) Americans in a canoe, and in the lower right corner, a couple of the underwater creatures encountered along the Virginia shore.

Is this the first published European representation of the Atlantic Horseshoe Crab (Limulus polyphemus)? It’s almost right. The tripartite body is well-rendered, but the legs are wrong, since they don’t actually extend from underneath the animal. It’s as if White and company crossed a Horseshoe with an actual crab. Though called “crabs,” Horseshoes are not members of the Crustacea.

One of the recorded Native American names for the Horseshoe is Se-ekanau or Seekanau. In English, it has been called the horsefoot crab, saucepan crab, soldier crab, king crab, and helmet crab. “Horsefoot crab” was coined by the British naturalist Thomas Harriot (c.1560-1621), who puttered around the New World (specifically that region that we’d now call the Carolinas and Virginia) in 1585 with Sir Walter Raleigh (c. 1554-1618) and thought the supposed crabs looked like horses’ feet. This is the source, via language’s slippery slope, of our name “horseshoe.” Meanwhile, the words in the binomial name actually do mean something. Limulus means a little askew, referring to the placement of the animal’s compound eyes. Polyphemus is the name of the one-eyed Cyclopes gorily blinded by Odysseus. (The much-studied and many-martyred Horseshoes have an impressive array of eyes and and other light-sensing organs and were instrumental in discoveries about vision, including human vision.)

Francis Parkman (1823-1893) wrote of Samuel de Champlain (1574-1635), who explored as far south as Cape Cod in 1604-1605: “The ‘horse-foot crab’ seems to have awakened his special curiosity, and he describes it with amusing exactness.”

A delightful show on wunderkammer at the Grolier Club revealed another of our old friends in the frontispiece illustration of Ole Worm’s Museum Wormianum, 1655, a catalogue of “one of the great attractions of 17th century Copenhagen.” ole worm


You should be seeing the shed exoskeleton’s of Atlantic Horseshoe Crabs on our beaches now. Note how they are hollow right down to the smallest joint.

As arthropods, Horseshoes must molt to grow larger: they do it about half a dozen times during their first year and then some 18 more times after that before reaching sexual maturity, at around 9 (males) – 12 (females) years of age. July and August are the big molting months.

The pewter pin in the picture showed up in the mail after I reported a tagged Horseshoe at Plum Beach in May.

Sheepshead Bay

Ten piers, ten local creatures of the sea.


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