Life Between the Tides: The Intertidal Region of Monterey County Coast

by Steven Harper

The tides are in our veins, we still mirror the stars, life is your child…
Robinson Jeffers

From the exposed rugged Big Sur cliffs to the relatively protected waters of the Elkhorn Slough, from rarely visited beaches and dunes of north-county to the heavily visited pier at the wharf, Monterey County is blessed with a unique, stunning, and diverse coastline. Hidden along this shoreline, and often missed, is one of the most fascinating and unique ecosystems—life between the tides. The central coast of California has one of the richest intertidal areas of the North Pacific Ocean. Organisms from the north and south converge their ranges creating an extraordinary diversity of species. Winds and currents push the surface water of the Pacific Ocean away form the shore causing an upwelling of colder nutrient laden water to rise. Plants flourish in these rich waters and provide nourishment right on up the food chain to the abundant organisms that inhabit, feed, and scavenge in the intertidal region.

Like the pulse of a planetary heartbeat, twice every day there are two high tides and two low tides. The highest and lowest tides of the month follow close to the moons cycle and occur near the full and new moons, roughly once every two weeks. The intertidal region is the area between the lowest tides up to the splash zone of the highest tides. The residents of the intertidal region are tough as nails and surprisingly delicate, and often both at the same time. The plants and animals that make their home here quite literally have a foot in two very different worlds. One home is the ocean, where they live in a saltwater environment, surviving currents and waves that pound with unrelenting power, where any number of predators from the sea comes to forage. The other world is that of land, where they must survive the direct exposure to wind, the sun’s heat and ultraviolet light, rain that dilutes salinity, not to mentions the numerous land animals and birds that come to feed. The organisms that have evolved to inhabit these two radically different environments have adapted over millions of years. It is in this extreme and dynamic environment where many scientists feel life first came to land.

I divide Monterey County’s coastline simply into three regions: rocky shoreline, sandy beach, and the protected waters of sloughs and bays. Many of the intertidal regions develop "life zones,” groups of organisms that live in distinct zones depending on their height above sea level. The rocky shoreline is the easiest place to see this banding together of organisms known as intertidal zonation. The rocky intertidal region is usually divided into four zones from the highest to lowest: the splash, the high intertidal, the mid-intertidal, and the low intertidal zone. If you happen to be at low tide along the rocky shore look down the shoreline and you can see the parallel bands of color. Each zone is distinct in its physical conditions as well as the flora and fauna that inhabit each zone. To some degree this zonation occurs in the sandy beach and slough environments, however it is often less distinct and more difficult to easily see at first look.

Most of our coastline is impacted by yet another and sometime tougher pulse than that of the tides. Wave after wave constantly caresses, or more often, pounds the shoreline. With an average of 5 waves a minute, 300 an hour, 7200 a day or an incredible 2,628,000 waves a year this constant force shapes and sculpts not only our coast but also the organisms that live here. From small 1-inch wind waves to monster waves measuring over 30 feet the shoreline is in almost constant movement. Sandy beaches seasonally demonstrate this continuous movement with the smaller summer waves tending to deposit sand while the larger winter waves tend to strip sand from the beach. Many of our sandy beaches disappear in the winter to return in summer.

The people of the central coast have always related to the sea and in particular the intertidal region. When it comes to the shoreline of the intertidal region we humans have often “loved the place to death.” We have a history of overusing this tough yet fragile ecosystem. As we understand more we hopefully will also change our actions and choices to protect our unique intertidal ecosystem.

If you decide its is important to learn more about our shoreline there are any number of good books and internet resources that will get you started. Additionally, we have the Monterey Bay Aquarium with its world-class exhibits and educational programs to guide and inspire your learning. Whether it’s to observe the abundant wild life or simply to listen to the sounds of the waves, head down to the shoreline with your senses alert and alive to its beauty. Here’s the important part… you don’t have to know the names of what you discover to enjoy your exploration. The most skilled naturalist engages all of their senses when observing the natural world. Take the time to thoroughly let in all that you observe. Be like a sponge and soak it in—you will be richly rewarded.

copyright Steven Harper all rights reserved

Visiting the Intertidal Region

Personal safety and safety for the environment are critical considerations when visiting the intertidal region:

Personal Safety
Some part of your awareness should be on what the waves and tides are doing. Just because the rock, beach or shoreline you are standing on is dry doesn’t mean it will stay that way. Rogue waves and an incoming tide can surprise even the experience local.

Environmental Safety
Learn the best low-impact way to visit your favorite shoreline. In heavily visited areas of the coast’s rocky shoreline it may be best to stay out of the intertidal region all together as human impact can noticeably damage the plant and animal life. What looks like rock or looks dead might be living. When you do go “tide pooling” pay attention to where you step. Leave rocks in place and refrain from disturbing the living creatures of the area.

Gray Whales: Nomads of the Sea

By Steven Harper

It felt like meeting an alien creature from another world. I stood in wonder looking out over the sea from a Big Sur precipice as these enchanting giants steadily moved south in their fluid weightless world. It was my first time to see a whale, and not only could I see the plumed spout of each breath, but I could also hear the explosive burst of each exhale as they rhythmically crested for each new breath. Finally, they gracefully lifted their massive tails and dove leaving only silence as I looked on in quiet awe.

Later I learned that I had witnessed gray whales on what is believed to be the longest migration of any mammal. They were on their annual journey south to their breeding and calving ground in Baja California Mexico. They pass off the coast of Big Sur again as they return north toward their feeding ground in the Arctic Ocean. Some years after this first sighting I followed the grays to both their Mexican and Arctic habitat where I have spent a total of many months watching and sometimes interacting with these incredible creatures.

Gray whales of the eastern Pacific spend the summer months from April to October in the Bering, Chukchi, and Beaufort Seas feeding on small crustaceans they sieve from the bottom of the sea floor. These baleen whales are believed to eat as much as 1 ton per day to add the 9 to 12 inches of blubber that is necessary to sustain their lengthy migration. They travel southward October through February swimming day and night covering a 100 miles as day all the while mostly fasting. They stay the winter months on both sides of the Baja Peninsula and near the coast of mainland Mexico. Pregnant mothers use the protected warm water of lagoons and bays to give birth to their young. Young whales can nurse 50 gallons of fat-rich milk a day gaining up to 70 pounds in a single day. These same lagoons and still waters are also used for mating. Often two males and one female can be seen in courtship behavior. When they mate, one male will sometimes support a female as another copulates with her.

They begin the two to three month northbound journey in January in two waves of departure and can be seen off the coast of Big Sur as late as May. The first group to leave Mexico often includes juveniles, males, and females that did not give birth. The second wave includes the mothers with their young and ailing or older individuals.

Scientists believe that 30 to 60 million years ago a group of land mammals returned to the sea. Over the course of time and environmental change the order Cetacea evolved into what we now know as whales and dolphins. While native peoples of the north hunted whales, the peoples of the south opportunistically used whales that washed up. With the discovery of their calving waters whalers hunted the gray whales to the edge of extinction in the mid 1800’s and again in the early 1900’s with the introduction of factory ships. In 1947 the gray whales were given full protection and have become one of the finest examples of how protection can save a species from the brink of extinction. Many scientists believe the eastern Pacific population is close to its original numbers.

Although unlikely to see, the most impressive event I have witnessed in Big Sur was observing a pod of orca whales take a gray whale and the ensuing two-hour red water feeding frenzy. While in the Big Sur take a moment to look seaward. Even if you don’t see a whale you’ll find something—expansive blue water, a wave, a moment that will inspire you—perhaps a moment of quiet awe.

What to look for in Big Sur
First off, if you are driving, pull off the road. Almost any pullout, restaurant, or trailside ocean view will do as long as it is not too close or far from the sea (50 to 500 feet elevation). A calm, windless day is optimal as white caps make it next to impossible to pick out a spout. November through April are the best months for whale watching in Big Sur.

Spouting: spouts of water and vapor form a whitish plume from each exhale. A migrating whale has a predictable sequence of 3-5 breaths in 20-40 second intervals
Sounding: when a whale raises its flukes (tail) to dive. Usually observed at the end of a cycle of breaths. The whale will often stay submerged for 3 to 5 minutes before it next cycle of breaths.
Breaching: Two-third or more of the whales body comes straight out of the water, pivots, and splashes back on its side.

Gray Whale Essentials
• Scientific name: Eschrichtius robustus
• Size: 35-50 feet (females are generally somewhat larger than males)
• Weight: 30-40 tons (60,000 to 80,000 pounds!)
• Color: dark gray with white mottling caused primarily by scaring and barnacles
• Fins: 2 pectoral fins 4 to 5 feet
• Flukes: flukes (tail) are 10 to 12 feet across
• Blowholes: 2 oblong in shape and about 8 inches long
• Dorsal Ridge: two thirds of the way back is a dorsal hump followed by 6 to 12 smaller humps or “knuckles” along the ridge
• Age: 40 to 50 years up to 60
• Speed: 2-6 mph and up to 11 mph in short bursts
• Diet: small crustaceans; amphipods (small shrimp-like krill)
• Reproduction: sexual maturity is reached around 6-10 years with a gestation period of about 12 to 13 months
• Population: estimates vary from 15,000 to 23,000
• Migration: 10,000 to as much as 14,000 miles round trip each year, taking 2-3 months each direction.

copyright Steven Harper all rights reserved

Wild Big Sur: Redwoods

By Steven Harper

The wild beauty of Big Sur has inspired and awed humans since, and probably before, recorded time. Whether you are a first time visitor or a long-time local, I invite you take time to acquaint yourself and deepen with this wild landscape. Slow down enough to let the raw beauty of nature touch you as it so creatively manifests itself along the coast.

It is all too easy to pass through Big Sur drinking in only the visual landscape. Yet, as any good naturalist knows, it is best if you use all of your senses. The most accomplished naturalists I know have not only developed visual acuity, they have also awakened their sense of smell, touch, taste, and hearing. What better place than Big Sur to let your five (or six) senses come alive? The natural elements invite you to pay attention.

When I bring visitors into the coastal wilderness I often introduce them to the natural history of this area through its plants. Plants are generally accessible, easy to find, and rarely run or fly away. They are low on the food chain, occur in communities, and interrelate with many other plants and animals helping us to connect with the larger natural environment. Plants engage our senses with lush colors, rich smells, intricate textures, complex tastes, and, yes, even sounds.

Monterey County has at least 2,055 plant species in 131 families with 68 species listed as rare or endangered. Big Sur accounts for a great deal of the abundant variety that occurs in this county. Due to the distinctive climate and extreme topography of the region, in a short distance a traveler can pass through an incredible display of diversity. A virtual tapestry of plant communities — from ocean side to deep canyon, open hillside to high peaks — offers a variety of habitats for plants to find their unique niches. Of the many plants that make Big Sur their home, probably the best known and easiest to learn is the coast redwood. Redwoods in their sheer magnificence draw our attention.

I would like to share here some of the unique qualities of redwoods to deepen your appreciation of these ancient giants. The Redwood (Sequoia sempervirens) is the tallest living thing on earth, measuring at up to 370 feet high. Fossil ancestors of this ancient tree are found to have been widespread in the northern hemisphere over 100 million years ago. They currently range from the California-Oregon border in the north to Big Sur in the south, growing in a narrow band 5 to 30 miles wide along the coast. They are found from just above sea level up to over 3,000 feet. Redwoods often live from 600 to 1200 years while some have survived to 2200 years old. Redwoods grow in a unique relationship to coastal fog and have evolved in close relationship to fire. A single old-growth redwood can produce millions of pin-head-sized seeds annually; however, unlike any other North American conifer, they most commonly regenerate clonally by root sprout. Where trees have been cut or have fallen due to natural causes, there are often “fairy rings” where younger trees have grown from the original parent tree. Surprising to many, redwoods have shallow roots 3-9 feet deep, but growing out from the tree for several hundred feet. Incredibly, mature redwood forests produce the greatest biomass per acre of any other forest in the world— almost 10 times that of mature tropical rain forest.

If redwoods are new to you, they can be found at almost all of the state parks and much of the Forest Service land along the coast in Big Sur. Whether you are new or old to the wonder of redwoods, I encourage you to find a tree, sit still, open your senses, and let yourself be touch by wild Big Sur.

copyright Steven Harper all rights reserved