Licensed under CC: photo by flickr user Elaine with Grey Cats. All rights revert to originator.
Santa Cruz County’s North Coast is an outstanding natural area because of climate, geology, unique species, rare habitats, and unusual natural processes. The North Coast combines two climatic features that shape its biological splendor: proximity to the cool Pacific Ocean and an adjoining Mediterranean climate. This climate drapes across the Franciscan Formation, a mélange of geological formations creating diverse soils and topography. Climate and geology alone could explain the many interesting and unique species, but North Coast richness is also due to the Santa Cruz Mountains having been evolutionarily isolated by ocean, bay, or extensive freshwater wetlands/river systems. All of the aforementioned combine to shape many rare habitats, in close proximity. In turn, Santa Cruz’ North Coast produces ecological phenomenon, processes, that we are only just beginning to appreciate.
The North Coast’s climate is found in few places of the world and is unique in North America. The roasting of interior California pulls cool, foggy air across the coast. Fog helps plants and animals make it through the dry summers. The wet winters combined with the very dry summers make it possible for moisture or arid loving species to coexist. With the right prevailing winds, mountains close to the ocean make rain. At 2660 feet, Ben Lomond Mountain is the backbone of the North Coast, assuring that the North Coast gets first dibs on rain from the winter storms which normally blow down the coast. During long droughts, fog and Ben Lomond Mountain’s claim on winter rains have maintained species that would have otherwise gone extinct. And so, we have extraordinary species diversity along our foggier and rainier coast in comparison to inland.
Besides weather, Ben Lomond Mountain is also responsible for our geology. The ‘basement’ of the Mountain consisting of granitics, schists, and crystallized limestone, pushed up through younger sandstone, mudstone, and shale. The diverse rocks create diversity you can easily experience: granitic stream boulders…craggy schist and sandstone cliffs…inland sand dunes…soil-less mudstone ridges contrasting with wide, deep soiled mudstone terraces…extensive subterranean limestone caverns.
For all of the above reasons, the North Coast affords many different species good places to live. More than 50 rare, imperiled, threatened or endangered species depend on this relatively small area (see prior blog, this website). This is why Santa Cruz County is known as a biodiversity hotspot: this small county has many species of Federally or State-recognized rare ‘herptiles,’ insects, and plants. A host of species are only found locally. For instance, the North Coast has two Manzanita species only on the North Coast. And, the caves of the North Coast are home to a host of species found only in North Coast caves. Even more widely distributed rare species, such as the California red-legged frog, probably depend on the North Coast for long-term survival on Planet Earth. My list of fifty sensitive species from the North Coast will grow because: 1) I haven’t added bats and mushrooms, yet, and; 2) Randy Morgan’s insect collection at the UCSC Natural History museum includes numerous new species, especially of bees, that have yet to be described and may exist only locally. So, more to come…
The habitats of the North Coast are wonderfully diverse. Redwood forests, dunes, grasslands, chaparral, oak forests, wetlands, beaches, cliff faces, streamside forests, lagoons…so many habitats, so close together! Many of these habitats are rare, and all experience a mix of fire, grazing, soil disturbance, and wind storms that shape them. Coast redwood forests are only in a narrow band on California’s coast, dripping fog moisture that supports lush understory plants through the summer. Dunes at the bigger beaches blossom year round with native plants, roots deep in the sand. Forty-five or more types of coastal prairie blanket flat uplifted marine terraces, cap rocky outcrops, or hold up vertical wildflower-covered slopes. Chaparral here, a.k.a. “maritime chaparral,” is like no other scrubby habitat, with many shrub species in poor soils, fed by networks of diverse fungi. Hundreds of species of fungi can be found under a single shrub in maritime chaparral. Stands of coast live oaks on the edges of grasslands are quintessential North Coast scenery. Less recognized are the dark green Shreve oak forests, acorn-strewn tan oak stands, patches of stately canyon live oaks, or shrubby interior live oak covered ridges. A very few natural, but many man-made, ponds are a-bob with amphibians; more common are the ephemeral wetlands on the terraces, or on top of rocky ridges…replete with odd algae, mosses and liverworts. Beach habitats, though nearly obliterated by human feet, still hang on along the less trammeled fringes. Above the beaches, and framing steep canyons, are the many nearly uncharted cliff habitats – so many mysteries. And, then there are the willow and alder forested canyon bottoms. Downstream, lagoons pulse fresh to salty with the changing tides and wave action: nurseries for salmonids, home to silvery goby fish and ducks. This diverse habitat-scape contrasts strongly with the grassy rolling plains of the Midwest or even the forests of the East Coast, where one habitat stretches for miles in every direction.
The biologically-produced ecological processes that this landscape supports are my real fascination, where the stories get richer and the mysteries abound. One story unfolding is with the coastal marine terraces, supporting an ecological staircase with more and more ancient soils, stepwise with each elevation gain travelling away from the ocean. This ecological staircase has been important in understanding how soils develop from bedrock. And, each terrace supports different types of habitat; first coastal terrace grasslands are extremely rare because that’s where we farm…fourth coastal terrace grasslands are rare, too, for other reasons. The higher terraces have 226,000 year old soils, probably the oldest soil communities in North America. The plant diversity of these grasslands has been produced through eras of changing climate and changing animal interactions. Pleistocene megafauna (camelids, mammoths, lions) gave way to more modern grazers (elk on the North Coast, mooo!) and then to very modern livestock: all stewards of the prairies, keeping brush at bay. Native peoples burned and tended this wildscape, a careful examination of even our current landscape will reveal their refined landscape management and agricultural practices.
Another ecological process story that is being told is about North Coast predators. Big cats, pumas, as apex predators are shaping much of the rest of the wildlife communities. Puma presence makes for fewer coyotes, more fox, and all that those shifts mean for bunnies, bobcats, and ground nesting birds. And, puma hunting changes deer behavior, with as yet untold affects on forest understory and streamside plants. My hypothesis is that the big, orange blossomed lily that you can occasionally view (Wilder and Laguna Creeks, for example) should be re-named ‘Cougar Lily’ – indicating the wariness of deer, which would otherwise trim those bouquets to the ground.
Other stories have yet to be told as we explore our curiosity. How important are the processes that move oceanic nutrients upslope to the poorer and poorer, ancient soils? Marbled murrelet carrying fish inland to tall redwood nestlings. Cojo salmon spawning upstream. Nutrient-laden fog drip moving inland. How crucial are these processes to feeding the plants that keep North Coast hills from more quickly eroding? Woodrats, mice, and voles – not just food for the predators, but also architects and builders: how does their nibbling contribute to: keeping grasslands open fields; making flat-topped gnarly trees, or; trimming shrubs to make room for others, creating diverse Manzanita glens. What is missing without grizzly bears tearing at stumps, breaking tree branches for acorns, digging up prairies for gophers?
The North Coast has so much to reveal through its naturally amazing, living systems. It is teaching us how to be indigenous by showing us how we can be better stewards. More people can see these stories by accompanying naturalists on tours, learning to recognize at least a handful of tree and shrub species, and by just plain observing, spending more time outdoors. Challenge yourself to tell your friends new ecological stories about the North Coast: where you see the wildlife, what shrubs are in bloom, what was swimming in the stream, colors of flowers at the beach. Sharing these stories will bring people together, help them cherish what they have, and create dreams about what is possible.