Saw weird clumps of mud on and around the shoreline as I set V7 onto the water. The clumps atarted to move slowly?!? Turned out to be mating horseshoe crabs. This is the first time I’ve seen in over three decades. I used to see them on beaches south of the Cape. First time I encountered these in MassBay.
I am glad the water just made 50 degrees. Warm for the year round surfer contingent but still too cold for the casual swimmers. The horseshoe crabs can do their thing unbothered.
-sing
Nice! As a Wildlife Biologist on Delaware Bay, that was one of the species I worked on.
Do you remember what the geographic range is/was for these creatures? I don’t remember every seeing these in MassBay proper. Saw them in Horseneck Beach and Buzzards Bay (south of Cape). Could range be creeping up because of the warming waters in the Gulf of Maine?
-sing
Good question! And there are many example in the wildlife realm of ranges shifting, both Northward (and to higher altitudes in mountainous areas) due to climate warming. Not to mention shifts in the timing of migration, the start of egg laying, etc.
But, in the case of horseshoe crabs, the range has been steady, going from Maine down to Florida, with an odd disjunct population on the Yucatan Peninsula. What you have observed is probably due to over harvest.
Horseshoe crabs are fascinating creatures. One of the most studied marine organisms. For example, their large optic nerve has helped us understand vision more than any other animal, I think. Their immune system provides us with a test that has become the world-wide standard for ensuring the safety from bacterial contamination of things like vaccines, pace makers, artificial knees, etc.
Interestingly, there used to be a law on the books in Massachusetts requiring people encountering horseshoe crabs on the shore to carry them up above high tide and leave them there to die. That was because they felt, at the time, that horseshoe crabs (which eat clams as part of their diet) were competing with the clam fishermen. That law was not taken of the books until sometime in the late 2000s, if memory serves.
But back to your question, you probably saw fewer, or even none, due to over harvesting by watermen who sold them to conch fishermen. This conch fishery, that drove the harvest of horseshoe crabs, and still is ongoing, started in the late 1980s or early 1990s. It was a new, unregulated fishery, and we have reports of tractor trailer loads of horseshoe crabs being taken from some NJ spawning beaches.
In the Delaware bay, by the late 1990s, anecdotal observations were that the spawning population of horseshoe crabs had declined so much that the excess eggs in Delaware Bay were in short supply for red knots, a shorebird highly dependent on these surface, thus threatening the red knot population. I guess I should add that the Delaware Bay was known to have, by far, the highest spawning population of horseshoe crabs in the world. All these crabs laid so many eggs that you couldn’t use the sand for concrete during breeding season, too many eggs in the sand. All these extra eggs (spawning crabs bury the eggs, but wave action and later spawning crabs dig some of the eggs up, and once at the surface, the eggs are either eaten or dry up and die) provide much needed food for the red knots.
Other places, like New England, anywhere horseshoe crabs could be harvested, were probably also in decline. I think the low point was around 2000, and I just took a look at Massachusetts data and that is what their seine survey (which they use as a population index for horseshoe crabs) shows. A period of decline from 1984 to 2000, and then an increasing population from 2000 onward. So if that is the time period of your observations it makes sense that in the local areas you were at, there may have been very few/none compared to today.
Horseshoe Crab Protection Enhanced in Massachusetts | Mass.gov
As declines were noted, btw, The Atlantic States Marine Fisheries Commission, a cooperative joint fishery management body was asked to add horseshoe crabs to their list of managed species, and since 2000 the harvest has been reduced and regulated, with focus on ensuring that red knots have enough eggs available for their needs during migration.
Sorry, you got me going, smile. I have too much info on this subject ready to spill out at the slightest provocation.
They’ll charge herd of old Roombas,
upon the coastal sand.
Man plots his clots within vacuumed bots.
Will he bleed dry most ancient plan?
Thanks. Appreciated the information. I was excited to see these creatures, I do vaguely recalled reading that these were over harvested for medical research/uses. I was also just glad to see these creatures again on the one of the shorelines I frequent after so many years (for me). 
-sing
“Holy humpin’ horseshoe crabs, Batman!”
I use to see so many as a kid along the Jersey shore, that I had to say “Ahem…Pardon me for interrupting,” and step around the intertwined couples.
(Do get some pics though, if ya happen to see any trilobites commiting prehistoric porn along Boston area bays–Now that’d be bigger news than when the Red Sox last won the World Series.
Yeah… they were going at it up and down the shoreline, as I slowly ease out into Hingham Bay. Fortunately for PCommers, I left the GoPro at home. Privacy was perserved.
-sing
All those eggs make great snacks for shore birds and fish every spring. Living dinosaurs.
Oh…
From the title I thought maybe it was about many of the members here.
I am an old man and I am younger than many posting on this forum. I do all I can to get younger people hooked on kayaking, but the age of the computer game is upon us and it seems outdoor activity is shunned by many of the current generations.
I resent being called a prehistoric sea creature because it’s just not accurate.
(The sea is a long way from me)
I suppose that is better than being called an archaic arthropod (crabby old man)!
Archaic Arthropod gone Prehistoric Sea Creature?
Why darlin’ you’re just touchin’ on my most redeemin’ features.
And now that I’m so far gone in what say you “Sea” in notion,
you might say Fogey Fossil I lands a Pre-Cambrian Implosion.
“…and the Horseshoe you came in on, too, sister!”
