Once upon a time there was a man named Henry Stellwagen.
We know that time was the mid-1800s, and Henry served in the United States Navy.
But that’s not why his name is still spoken by people who fish, whale watch, or just like being on the water. We invoke good old Henry Stellwagen because a swath of nearby water is named after him; Stellwagen Bank.
Fishermen had long known about shallow grounds beyond the tip of Cape Cod, stretching roughly north and west toward Gloucester. Geologists will tell you that this arc from Provincetown to Cape Ann was dry land thousands of years ago, when sea level was much lower.
Like many places where the bottom rapidly rises, currents and upwells create a fertile mix, attracting fish from tiny to huge which in turn attract fishermen from across New England.
But this place had never been charted.
In 1854, Stellwagen was on loan from the Navy to the U.S. Coastal Survey. He was on a steamer, mapping. One reason why Stellwagen had been chosen was that he was ingenious; he had invented a new device that could “sound,” dropping to the floor to record depths, bringing up samples offering a good idea of the terrain down there. He had fashioned a cup placed below a sounding lead with a valve of leather that acted like a little scoop --- simple, effective.
In October, Stellwagen, excited, wrote to his boss, the superintendent of the Coast Guard Survey, with big news:
“I consider I have made an important discovery in the location of a 15 fathom bank lying in a line between Cape Cod and Cape Ann … It is not on any chart I have been able to procure. We have traced nearly five miles in width and over six miles in length, it no doubt extending much further.”
Stellwagen was excited because his discovery would be important for navigation in and out of teeming Boston Harbor, “particularly in thick weather, determining position with great accuracy … I consider the delineation of it as of more importance to the Mercantile world than the erection of a lighthouse.”
His boss sent a fast response:
“Do not leave Boston without receiving explicit instruction, except to determine this bank.”
Stellwagen charted an underwater plateau 19 miles north to south, six miles across at its widest southern point. Depth below surface is roughly 100 to 120 feet, much shallower than waters around it that range to 600 feet. Earlier mariners thought there were two shoals out there, but Stellwagen confirmed it was one body.
In an 1854 annual report, Stellwagen’s boss highlighted the discovery “as an excellent mark for navigators entering this important bay. I propose to call this, from the name of its discoverer, Stellwagen’s Bank.”
Stellwagen Bank National Marine Sanctuary came into being 138 years after Henry sent down his sounding device, in 1992. The word “sanctuary” seems a bit off; Stellwagen has been a busy commercial thoroughfare and fishing grounds for centuries, far from pristine, urban by marine standards. Fishermen were nervous that the designation would lead to closures, but commercial fishing continues on Stellwagen, while industrial exploitation like sand and gravel mining are off the table. Whales still congregate, creating the lucrative whale watching industry.
Henry would have been pleased. He didn’t want his namesake discovery to be off-limits, on the contrary. He wanted it to be understood.
