One Giant Sand Bar
In the beginning, there were the glaciers. The Cape and islands were formed relatively recently, merely 18,000 years ago, during the last episode of global warming, when glaciers receded from the area and left a sandy substrate. In other words, parts of the Cape and islands -- particularly, the Outer Cape and Nantucket -- are actually just giant sand bars. But what fine sand bars they are.
The best way to explore the geologic and natural essence of Cape Cod is with a visit to the 44,000-acre Cape Cod National Seashore. Stretching from Chatham to Provincetown, it covers 40 miles of pristine beach, marsh, kettle ponds, and uplands. There are miles of biking and walking trails, including one in Truro that passes by a wild cranberry bog.
In the geologic scheme of things, Cape Cod is sort of a here-today, gone-tomorrow phenomenon. Cape Cod's outer beach sees an erosion rate of about 4 feet per year. So the place is quite a bit different from when Henry David Thoreau walked from Eastham to Provincetown on the Atlantic side of the coast in the mid-19th century. However, a walk along the shore can still be the setting for a range of surprises. A simple stroll along the beach may present a piece of cloudy sea glass, stones and seashells of all shapes and colors, or even a glimpse of a pod of whales offshore. A great beachcombing site is the shoreline of Brewster, on Cape Cod Bay, where the tide recedes and leaves what seems like miles of ocean floor perfect for exploration.
The terrain of the Outer Cape feels different from the rest of the Cape. Larger trees, such as oaks and elms, are replaced by pitched pine and scrub oak. This is where dune grass, beach plum, and Rosa rugosa, the hearty beach rose, are sometimes the only thing holding the sandy ground in place. But these fragile and rare habitats, such as the Atlantic White Cedar Swamp Trail, near Marconi Beach in Wellfleet, are where many rare and beautiful species, such as the delicate orchid called lady-slippers, can be found.
The salt-marsh habitat, which is found in all parts of the Cape and on both islands, is considered one of the keys to the health of estuaries and ponds. It works like a natural filter, cleaning groundwater before it enters estuaries. It was not too long ago that these areas used to be called swamps, and they were filled and paved for construction of such things as shopping malls. Now they are protected with some of the toughest environmental regulations in the country.
Here Today, Gone Tomorrow -- The shoreline has eroded about a full mile since Colonial times, and current scientific predictions give the Cape and islands a projected life span of as many as 5,000 more years -- or as few as 500. Not to make light of the situation, but this is all the more reason to enjoy them while you can.
The wetlands of the Cape and islands are part of one of the country's greatest annual wildlife spectacles: the passage of thousands of migratory birds in spring and fall. Warblers, herons, terns, and oystercatchers; shorebirds, such as avocets and the endangered Piping Plover; dozens of species of ducks; huge flocks of snow geese, owls, and hawks -- these are just a few of the birds that take a rest stop on the Cape as they pass along the Atlantic Flyway, which, for some birds, extends from winter homes in South America to breeding grounds in the vast, marshy tundra within the Arctic Circle.
March, April, October, and November are all good months to see migrating waterfowl. August is the month to observe migrating shorebirds, with thousands stopping to feed at such places as Monomoy Island, Nauset Marsh, and Sandwich's Great Marsh. Fewer shorebirds stop at the Cape in spring, but those that do will be decked out in the bird equivalent of a tux -- their breeding plumage. Songbirds pass through in May, in their brightest plumage and in full-throated song (both color and voice are muted during their fall migration). If you're birding on the Cape during the height of the summer season, you'll find plenty of herons, egrets, terns, and osprey wherever you find sand and wetlands.
The Piping Plover, a small, sand-colored shorebird, is a threatened species that nests on Cape Cod. Its populations are so small that each pair that nests is watched closely. The Cape Cod National Seashore is considered one of the most important nesting areas for the Piping Plover, and beaches in several parts of the Cape, including Nauset Beach in Orleans and Race Point Beach in Provincetown, are closed every year while the Piping Plovers nest. Ignore the bumper stickers that say PIPING PLOVERS TASTE LIKE CHICKEN and learn to love these tiny little birds that live on the shore's edge.
The other great wildlife-watching opportunity this region is known for is whale-watching. The humpbacks, huge finbacks, and small minkes all cluster to feed around the Stellwagen Bank north of Provincetown from April all the way through November. Monomoy Island is worth a special trip for seal-watching. In late winter, thousands of harbor seals take their version of a holiday in the sun, retreating to Monomoy from Maine and points north. Many stay for most of the year. They share the island with thousands of wintering sea ducks, as well as other migrating birds in the spring and fall. For info call the Cape Cod Museum of Natural History (tel. 508/896-3867).
Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.