Natural History

Seven distinct ecosystems coexist within Rancho del Oso. A rare pine forest occupies an area just beyond the coast. Further inland, the valley is dense with redwoods. Alder and cottonwoods line the banks of Waddell Creek, while cypress, madrone, fir, and bay laurel grow on the adjacent slopes. Many striking flowers, such as leopard lily, fairy lantern, and California lilac (Ceanothus) grow in the area as well.

The Waddell Valley is also a sanctuary to several endangered and threatened species, including red-legged frogs, San Francisco garter snakes, steelhead, and Coho salmon. There have been more than 250 species of birds sighted in the valley and on Waddell Beach, including golden and bald eagles, pileated woodpeckers, osprey and snowy plovers. The endangered marbled murrelet, a seabird that flies inland to nest high in the tops of old growth redwoods, also makes its home here.

Ecosystems of Rancho del Oso

Coastal Strand – beach and dunes
Inhabited predominately by shore birds and plants well adapted to growing in wind, salt spray, and shifting sands. Tide pool dwellers are revealed when the sea recedes from rocky outcroppings at the shore’s edge. Glimpses of marine mammals are also possible from this vantage point.

Coastal Scrub – bluffs above, and open areas just inland from, the beach
Plants growing here are low and dense, due to persistent winds. They shelter small mammals, reptiles, and songbirds, from sharp-eyed hawks soaring overhead. Once-prevalent coastal prairie species can also be found here. Fragrant foliage is a common feature of this ecosystem, as are flowers in vibrant shades of yellow, orange, and red, appearing in late spring and summer.

Monterey Pine Forest – slopes near the coast
Planted for lumber worldwide, the Monterey Pine only occurs naturally in a few places: three small areas in California, and two tiny islands off Baja California in Mexico. The groves found here are near the northernmost extent of the trees’ range. Pitch canker, a fungal disease thought to be spread predominantly by wind and bark beetles, has taken a toll on many trees in recent years.

Marsh – low lying areas near the mouth of Waddell Creek
Fish, frogs, and turtles thrive here, as do waterfowl and wading birds. Plants like rushes and sedges, that prefer to keep their roots wet, are abundant. On the periphery, footprints of raccoon and other mammal visitors decorate the mud.

Riparian zone – vegetation along Waddell Creek
Fish inhabit the deeper pools, while birds and mammals quench their thirst in the shallows, and insects hover just above the surface. Moisture loving trees, shrubs, and herbs grow along the banks, providing shade, shelter, and food, around these important fresh water sources.

Redwood Forest – valley floor and shaded slopes above
Redwoods are thought to be the tallest trees in the world. They supplement water received from rainfall by collecting fog drip with their needles, which in turn form a thick mulch on the forest floor, further conserving moisture. Plants and animals seeking damp shade – from ferns and berries to banana slugs and newts – dwell on the forest floor.  Other species take cover in the trees’ abundant foliage.

Mixed Evergreen Forest – sunnier, drier slopes above the valley floor
Oak, fir, madrone, and fragrant bay laurel trees, dominate the canopy of this extensive and diverse plant community. Woodpeckers, owls, and jays inhabit the upper stories of the forest, while deer browse below and squirrels scamper throughout.