The Limantour Spit is a world of its own, isolated, windswept and surrounded by the sea. In a park filled with natural wonders, the sandspit stands out as exceptionally wild and primal, backed by broad estuaries, white cliffs and rolling headlands exposed to the raw forces of nature. 

The spit breaks away from the mainland at the trailhead where the big steel bridge crosses the tidal channel. For a few decades, the marsh just south of the trailhead was cut off by a ranch dam and the road to the beach lots of a proposed 1960s development. With the installation of the bridge, the tidal hydrology was restored. The dunes separating the marsh and the beach mark the beginning of the spit.

As the Point Reyes peninsula slid north along the San Andreas fault over the last 100 million years, it accumulated massive sedimentary deposits. The most recent of these—soft, unconsolidated siltstones—were formed several million years ago in the Drakes Bay basin. At the lighthouse, the Point Reyes Headland juts out into the south-running Pacific Ocean currents, causing a counter-clockwise gyre in Drakes Bay that slowly sweeps sand northward, creating the sandspit and its estuary, the Estero de Limantour. The gyre, and storm-driven winter surf from the south, have carved miles of these deposits back to the white-rock cliffs around Drakes Beach.

As the spit slowly grew, it protected the cliffs behind it from exposure to the storm surf. No longer eaten away at their base, the cliffs behind the spit are more sloped, covered with brush and cut by erosional ravines. But the first cliff behind the mouth is still exposed to eroding surf and is steep and clean, and cut further back like the ones around Drakes Beach. The contrast between these rocky cliffs brings geologic time to life. 

The southern end of the estero is a broad sweep of fertile mudflats and winding tidal channels built with the muds of Muddy Hollow and covered with pickleweed and salt grasses. All this organic material supports dense populations of invertebrates, from micro-organisms to large worms and a wide variety of mollusks, crustaceans and arthropods. These land-derived mudflats meet the ever-building sand dunes and together form the spit and the broad flats inside the estuary. 

The dunes, up to 40 feet high in spots, spread back from the beach into a wide and deeply carved band covered with dense stands of low European dune grass, lupines and coyote brush, along with occasional pines, willows, ceanothus, coffee berry, sea rocket, sand verbena, blackberry and invasive mats of iceplant. From the tops of the foredunes, across the dry sand of the upper beach and out to the surfline, the beach is constantly resupplied with a flotsam of kelp, eelgrass and dead birds washed up at high tides. This supports a lively population of beach flies that quickly hatch eggs in the decaying kelp.

The central dunes are busy with wildlife. Dense populations of deer mice and brush rabbits live here, indicated by the countless speckles of mouse tracks and huge drifts of rabbit scat under the lupines. A variety of other animals inhabit the area, leaving their tracks and signs. Gophers, moles, voles, shrews and jackrabbits are common. Raccoons rest in well-hidden hollows in the backdunes and forage for beach crabs during low tides at night. They leave middens of crab shells and scat latrines just behind the first line of dunes, where they dine in hiding. Opossums forage for insects, mice and anything else that might be edible. The striped skunk is common, but its smaller and rarer cousin, the spotted skunk, is present, too, with a distinctly different gait and tracks. 

Coyotes regularly hunt the dunes for rodents and patrol the edges for flotsam. Bobcats occasionally venture up the spit, threading through the contours of the dunes where they can stay hidden. Deer and elk are resident browsers, elk sometimes foraying all the way to the northern tip of the spit and back, unafraid to cross the long, open expanses. Just offshore, fish-hunting sea lions are a regular presence, along with extensive flocks of clown-faced surf scoters ducking and diving in the surf and resting in the still water farther out.

Birds are abundant and diverse, with a constant ebb and flow of shoreline species. Thousands of sandpipers and plovers scurry along the shore and across the dry beach, picking and probing for insects and other invertebrates in the sand and around the drifts of kelp and eelgrass. They are joined by huddled flocks of hundreds, sometimes thousands, of roosting gulls and pelicans. The bird and sea mammal carcasses that wash ashore are a constant food source for ravens and vultures that leave surprisingly long walking trails in the sand. 

Back in the mudflats and marshes, a wide variety of waders and probers come and go with the seasons, attracted by all the life in the mud and silt. Flocks of curlews, whimbrels, godwits, dabbling ducks and diving ducks leave excellent and varied tracks on the mud at low tide. In the channels and bays, fish attract herons and egrets, pelicans and cormorants. Ospreys and bald eagles regularly hunt for bigger fish in the deeper water, using pine trees in the headland ravines for perches. In between, seed- and insect-eating sparrows and the occasional warbler or pipit forage in the dunes. Harriers patrol back and forth just over the chapparal, repeatedly swooping to surprise a rodent. 

About a mile up, in an abrupt shift, the dunes break into islands separated by wider and wider stretches of sandflats that are flooded by extreme high tides and storm surf. With each break, the dune clusters become more isolated and the diversity decreases. Coyotes make regular journeys all the way to the northern tip, and the still-abundant mice and rabbits even entice an occasional bobcat who will cross the open expanses in a fast trot, then slow to the usual amble as it hunts through the dunes.

A key feature of the sandspit is hidden from sight. Rainwater accumulates in an aquifer just under the surface of the sand, and since freshwater floats on denser seawater, it is accessible. This is the water that sustains the deep-rooted plants and animals of the dunes.

Though mice and rabbits can survive on the moisture in plants, larger animals need a direct source of water. I wondered where they found it out there, two or three miles from the creeks. Coyotes can easily trot at a sustainable speed of 15 miles per hour, allowing them to return from the end of the spit in only 10 or 12 minutes—astonishingly fast. But they have another trick up their furry sleeves if they decide to stay out longer. 

Coyotes sometimes dig small wells in the deepest pockets of the dunes. I have found three of these wells, which can be as deep as 18 inches and hold drinkable water until late fall. There is an altruistic element to the well digging, as a wide variety of other animals come to drink, including raccoons, skunks, deer, rabbits, sparrows, ravens, hawks and bobcats. I’ve seen all their tracks and scat around the wells. 

Marine mammals—seals, sea lions and sea elephants—haul out at the very end of the spit on sand bars and in the protected shoals. And we can’t forget the ever-exploring river otters, whose tracks and trails show up regularly on the inner shoreline of the upper spit. Always tread respectfully and give them a wide berth. The area is subject to seasonal closures to protect pupping pinnipeds. 

As teenagers, before the park was established, my brothers and I used to drive jeeps up to the end of the spit and I was always tempted to swim across the mouth. Finally, 60 years later, I gave it a try. I hiked down from Drakes Beach with an adventurous friend and caught the perfect moment at an extreme low tide when the crossing was but a 50-yard swim. Even so, the current was deceptive, and the chilly water began carrying me out toward the surf. The danger of getting caught between surf and tide was clear, with a short window before exhaustion and hypothermia would set in. A few strong strokes and I made a grateful landfall at this lonely point and continued on my way.

Richard Vacha is a nature lover and animal tracker, author of “The Heart of Tracking” and founder of the Point Reyes Tracking School. He lives in Point Reyes Station.