About 12,000 years ago, the northern third of the Earth was covered with a thick sheet of ice. Over the previous thousands of years, the icepack received more snow each winter than melted each summer, so it grew larger and heavier. The weight of the added snow and ice pushed the leading edge of the ice southward across Cape Cod Bay, dredging up rocks and crushing them against each other. Cape Cod was a long pile of rocks and sand at the front edge of this huge glacial tongue of ice. The glacier stood nearly a mile tall along the north shore of today’s Cape Cod. Sandy Neck and the Outer Cape beyond today’s Brewster did not yet exist. Previous ice ages had dredged up today’s Nantucket and Martha’s Vineyard.
The earth was warming, and the ice had stopped advancing toward the south. Huge waterfalls splashed off the wall of ice, and occasionally massive blocks of ice toppled off. A group of huge blocks crashed off, breaking into three pieces and creating the three lobes of Long Pond. As the ice melted and receded, a larger chunk fell and created Lake Wequaquet. The ice chunks were surrounded by sand and stones washed out of the glacier. As the fallen ice melted, the pond water rose to its present level. Many such ‘kettle ponds’ were formed from the grand ice falls, like Walden Pond in Concord. This process happened almost a thousand times on Cape Cod.
With no connection to the Bay or Nantucket Sound, Long Pond had no fish. Perhaps native Americans released some and started its fish population. In 1867, a group of unemployed Civil War veterans were hired by the town to dig a ‘herring run’ from Nantucket Sound up to Long Pond and on to Lake Wequaquet. They excavated by hand, using horses to pull the loads of dirt and rock from their project. The ditch they dug is our herring run, now called the Centerville River.
Today we benefit from this rich history, with herring swimming up our run to spawn each April and May, then leaving for their ocean home soon afterwards. Their minnows remain in our pond until late autumn, providing food for the bass and sunfish, and eventually coming back to spawn at the age of three or older. Scientists estimate that only one in a thousand survives to spawn.
Our heritage is threatened by the annual cyanobacteria bloom, the invasive weed Hydrilla, and other byproducts of human settlement around Long Pond. Our pond is a finite resource, and these threats could ruin it for all – humans, herring, osprey, turtles, bass, and others. Our septic systems, lawn fertilizer, and storm runoff from driveways and streets pollute it. The Association for the Preservation of Long Pond seeks to preserve the pond in its original state, for enjoyment today and for generations to come. By taking action together, we can save the pond from ourselves.
