Animals

Endangered Birds

The endangered California brown pelican have been observed roosting at Seal Rocks, Alcatraz Island, Hyde Street Pier, Bird Island, and Kent Island in Bolinas Lagoon. Brown pelicans feed on small fish such as the anchovy along the Pacific coast and in Bolinas and Rodeo lagoons. Threats to this species inlclude boating and active recreation in roosting areas, pollution and oil spills, and climatic factors affecting anchovy availability.

The endangered American peregrine falcon has historically nested at three sites in Golden Gate between the Golden Gate Bridge and Muir Beach since 1990. Peregrines are also known to over‑winter on Bolinas Lagoon. Between 15 and 30 peregrine falcons of all three subspecies — tundra, Peale’s, and the continental — have been observed in the GGNRA by the Golden Gate Raptor Observatory. Threats to this species include visitation by fishermen and adventurers, and toxic contaminants. Peregrine falcon decline is linked to the organochlorine pesticide DDT, which thinned egg shells, causing parents to cruch their own offspring. DDT was banned in 1972, but other organochlorines still enter the local environment. The peregrine falcon has been proposed for de-listing by the U.S. Fish and Wildlife Service (USFWS). 

The threatened northern spotted owl was listed by the USFWS in 1990. Northern spotted owls are widely distributed in forested regions from southern British Columbia through Washington, Oregon, and northwestern California. They reach the southern limit of their range in Marin County, where they occur in Golden Gate National Recreation Area, Muir Woods National Monument, Point Reyes National Seashore, and other parts of the county. These three national park units began a joint systematic survey for spotted owls in Marin County in 1993. Preliminary results of these surveys indicate that the county may support the highest density of spotted owls nationwide. Northern spotted owls are typically found in old- and mature second-growth forests, but in Marin County they reside in second- and old-growth Douglas fir, bishop pine, coast redwood, mixed conifer-hardwood, and evergreen hardwood forests. Threats to this species include urban development along protected-area boundaries, intense urban recreational pressures, potential for catastrophic wildfires due to unnatural fuel buildup, possible genetic isolation, and range expansion of the barred owl.

The threatened marbled murrelet are found in forest stands with old growth characteristics, and are extremely sensitive to disturbance and noise in the vicinity of nesting areas. A few unverified inland sightings have been reported since 1990. Systematic surveys have been conducted in Muir Woods National Monument and no murrelets have been detected. Marbled murrelets are infrequently seen in nearshore waters from mid-summer through winter. Detection of breeding murrelets in Marin would be extremely significant as there is a geographical gap between breeding populations in San Mateo and Santa Cruz counties to the south, and Mendocino County to the north. Threats to this species include range expansion of ravens, urban development, and urban recreational pressures.

The threatened bank swallow colony at Fort Funston is the largest nesting colony of bank swallows in the San Francisco Bay Area. Bank swallows migrate from South America to nest in the hundreds of burrows that cover the sandstone cliffs. Watching these aerialists capture insects on the wing and then feed their young while hovering in front of the burrows is a sight to see. Threats to this species include burrow invasions from European starlings, predation by American kestrels, and conflict with recreational uses such as hang gliding and rock climbing. The sandstone bluff is extremely erodible, and intense storm events are also a threat. 

The threatened western snowy plover was listed in 1993. This small bird over-winters on Ocean Beach in San Francisco from July through early May. Hiding in small depressions in the sand just beyond the tide line, many visitors who recreate at this beach never knew they were sharing space with the plover. The park established a snowy plover management area from Sloat Boulevard in the south to Stairwell 21 in the north along the O’Shaughnessey seawall, based on several years of monitoring data. Threats to this species include recreation such as off-leash dog walking and intense storm events.

Birds

The most visible wildlife in Golden Gate are definitely the birds. You will see them rustling in the bushes near a path, soaring overhead, or floating across a marsh. An astonishing number of avian species live in or migrate through Golden Gate. A variety of habitats ranging from open water and protected bays, to rocky and sandy shorelines, to tidal marshes, coastal scrub, grasslands, and forests create many different habitats that support over 250 different birds. Golden Gate lies along the Pacific Flyway, and is also host to a variety of transient birds that stop over to rest and feed in their amazing journeys from equatorial regions as far south as the South American rainforests to polar regions as far north as the Canadian arctic. This combination of factors makes Golden Gate a birder's paradise. The Audubon Society, California Partners in Flight, the California Department of Forestry, and the Fish and Wildlife Service all monitor bird activity in the park for species of concern.

Park creeks attract neotropical migrants: small songbirds making their way up and down the coast each fall and spring. Along Redwood, Lagunitas, and Lobos Creeks riparian songbirds such as olive-sided flycatchers, Swainson’s thrush, Wilson’s warbler, tanagers, and grosbeaks can be heard trilling their territorial and reproductive calls. Two species, the willow flycatcher and the bank swallow are considered threatened by the state of California.

The old growth forest of Muir Woods represents a fragmented island of the redwood stands that existed 150 years ago. Muir woods is now the last remaining contiguous stand of old growth coast redwoods in Marin County. Underneath the dappled sunlight, high in the branches of these giants, federally threatened species such as the northern spotted owl nests. Marin County is home for a fairly large population of these small owls that have found themselves spotlighted in the media.  At least 69 bird species occur within Muir Woods, the majority of which are small neotropical migrants such as the Pacific-slope flycatcher, winter wren, golden-crowned kinglet, and chestnut-backed chickadee.

The precipitous cliffs and offshore rocks that flank the park are a haven for colonial seabirds. Bird Island off of Rodeo Lagoon is one of the largest roosting sites in northern California for the endangered brown pelican, with several hundred making a splash in Rodeo Lagoon each Fall. Brandt’s cormorants nest at Lobos Rocks and Seal Rocks along Land’s End in San Francisco, turning the rocks bright white with their strong-smelling guano. Pelagic cormorants nest in very small colonies on steep cliffs and sea stacks from the Golden Gate north to Stinson Beach. Peregrine falcons are seen in their kamikaze dive, foraging along the coastal cliffs and have nested from the Golden Gate Bridge north to Muir Beach.

Colonial nesting waterbirds have found not a prison on Alcatraz Island, but inviting habitat in which to nest during the Spring and Summer months. In one of the most internationally visible settings within the National Park Sysytem, Alcatraz supports black-crowned night-herons, Brandt’s cormorants, pelagic cormorants, and pigeon guillemots - the only colonies found in San Francisco Bay for these species. Most colonial nesting waterbirds breed on offshore islands.  The island’s large western gull colony represents a significant portion of its coastal breeding population in northern California.  

Sandy beaches and mucky estuaries provide important habitat for migrating and wintering waterbirds and shorebirds. Tomales Bay, Bolinas Lagoon, Stinson Beach, Muir Beach, Big Lagoon, Rodeo Lagoon, Crissy Field and Ocean Beach, provide habitat for loons, grebes, scoters, numerous species of dabbling and diving ducks, gulls, terns, willets, sanderlings, and sandpipers. Federally threatened western snowy plovers overwinter in Ocean Beach. The park's mudflats provide plenty of tasty invertebrates, and estuaries provide fish and crabs galore. The San Francisco Bay is an important stopover for migrating species both due to its size and diversity of suitable habitat. Nearshore marine waters just outside the Golden Gate also provide foraging sooty shearwaters and pigeon guillemot, with thousands of birds rafting together on open water.

An island of green in an urban matrix, the Presidio’s location on the northwest tip of the San Francisco peninsula offers a stopover location to many birds before crossing the Golden Gate Straights, or as an entrance gate to the rich wetlands of the San Francisco Bay. Native habitats and introduced forest are regionally important to locally declining species such as the California quail, western screech owl, wrentit, and Hutton’s vireo. The landscaped areas of the Presidio also attract some interesting birds. The hooded oriole reaches the northern limit of its breeding range in the Presidio due to the royal palms planted throughout this former Army Post.

Amphibians

Hidden under logs or in dense vegetation, amphibians are among the least seen wildlife of the park. You may have heard a Pacific chorus frog chirping near a creek, or seen the California newt on its yearly migration. Sodden areas near creeks and marshes are the best place to find amphibians. In locations such as Big Lagoon near Muir Beach, soft clear balls of amphibian eggs attach to emergent vegetation, and male frogs call out to potential mates. Or in forested areas, a check under fallen logs will most likely turn up slender salamanders. Amphibians are highly sensitive to pollution, and a close eye on these animals can alert park managers to potential contaminants in wetlands and in the atmosphere.

The threatened California red-legged frog has been extirpated from 70 percent of its former range. Threats to this species include urban encroachment, construction of reservoirs and water diversions, introduction of non-native predators and competitors such as the bullfrog, livestock grazing, and habitat fragmentation.

Animals

Golden Gate's urban features may seem to suggest a lack of wildlife, but there is much more than meets the eye. Golden Gate's coastal ecosystems supports a rich assemblage of wildlife including 387 vertebrate species. The park's grasslands, scrublands, wetlands, and forests also support a rich diversity of invertebrates, although these species have not been well inventoried. The Recreation Area is home to nearly 53 species of mammals, 250 species of birds, 20 species of reptiles, and 11 species of amphibians.  

Some animals are picky about the place they call home, while for other animals anywhere with food, shelter, and water will do. Habitat generalists occur across a broad range of plant communities found in the park. Habitat specialists are adapted to the conditions of one particular habitat. Chaparral or prairies may provide a glimpse of rabbit, quail, or bobcat. Forests and woodlands may lead you to a black-tailed deer, banana slug, or spotted owl.  Marshes and creeks host an array of amphibians, fish, and reptiles including the red-legged frog, San Francisco garter snake, and Coho salmon.  All habitats support a variety of insects, and bees and butterflies abound.

Many wildlife have evolved a preference for specific vegetation to provide their food or shelter, such as the endangered mission blue butterfly and its host plant the silver-leaf lupine. Other wildlife use the park as a natural corridor in their yearly migration routes. Smack in the middle of the Pacific Flyway, hundreds of bird species use Golden Gate as open space to rest and refuel. Marine mammals such as whales, seals, and sea lions make use of the park's varied coastal habitats, with numerous haul out and pupping sites spread throughout the length of the park. Migratory insects such as the monarch butterfly return to the same tree stands year after year to overwinter.

Whether using park resources broadly or specifically, year round or for less than twenty four hours, all of these animals depend on the Recreation Area as a refuge from expanding development outside of park boundaries. There are over 80 rare or special status wildlife species currently identified as permanent or seasonal residents of the park, or dependent upon park lands and waters for migration. Of these, 12 are listed as federally endangered, and 12 are federally threatened.

Other Invertebrates (corals, sponges, worms, etc.)

More than 24 miles of ocean and bay border Golden Gate. Coastal and bay resources comprise biologically diverse and complex ecosystems, which contain a rich array of marine invertebrates and algae. Intertidal communities within or adjacent to park boundaries include natural islands, reefs, offshore rocks, straits, lagoons, mudflats, and beaches. Man-made habitat include piers, wharves, and shoreline rubble. The Gulf of the Farallones Marine Sanctuary is just offshore, and the San Francisco Bay-Estuary empties through the straits of the Golden Gate. Slide Ranch, Muir Beach, Pirates Cove, Kirby Cove, Fort Point, and Alcatraz display a rich diversity of sponges, bryozoans, tunicates, limpets, mussels, anemones, and sea stars on their rocky headlands. Barnacles and isopods cover the splash zone. Sea caves abound in the park and have yet to be inventoried.

At Rodeo Beach Bird Rock (a guano-covered sea stack), marine invertebrates include large chilipepper shrimp, California mussels, and green anemone and purple seastars. Less common invertebrates include abalone and sea urchins. Rocky intertidal areas are interspersed throughout Marin County at Stinson Beach, Slide Ranch, Muir Beach, Tennessee Cove, Rodeo Beach, Bonita Cove, Kirby Cove, and Lime Point. The intertidal zone along the coast of Marin County is generally steep and rocky, with small beaches occurring adjacent to watershed drainage areas, and not easily accessible by the public. In San Francisco County intertidal areas are primarily beach or pier habitat including Fort Funston, Ocean Beach, Land’s End, China Beach, Baker Beach, Fort Point, Crissy Field, Fort Mason, Black Point, and Aquatic Park. Many of the intertidal areas serve as living outdoor classrooms for Bay Area residents and visitors. The state‑protected Dungeness crab breeds in the Pacific Ocean just offshore, and many Dungeness juveniles, as well as other species of shore crabs, can be spied in the park's rocky areas and mud flats

The California freshwater shrimp is endemic to Marin, Sonoma and Napa counties, but only remains in portions of 16 coastal streams. Lagunitas Creek in Marin County contains the most viable population of the shrimp and it is the only site occurring on protected lands. The shrimp is threatened by water diversions on Lagunitas Creek, watershed erosion, stream sedimentation, riparian vegetation removal, agricultural development, grazing, and urbanization.

Mammals

These furry members of Golden Gate's wildlife seem to attract the most interest from park visitors. Despite the urban development and habitat fragmentation that continues to occur in central coastal California, the park supports a diversity of mammals. The fauna of today are very different than the variety of species found here before the arrival of the Europeans in the 1700s. After the Gold Rush, local grasslands and scrublands were quickly replaced with dairies and farms to support this emerging metropolitan mecca. Long gone are the large mammals such as the grizzly bear and tule elk of early California. But high densities of mesocarnivores, including the gray fox, bobcat, and the recently reestablished coyote inhabit coastal scrub and grasslands across Marin and San Mateo Counties. Mountain lions sightings regularly occur throughout undeveloped areas of these two counties. These carnivores feed on a variety of small and large mammals such as the black-tailed deer, broad-footed mole, pocket gopher, deer mouse, western harvest mouse, California vole, badger, and brush rabbit.

The shady forest world of Muir Woods supports 30 species of mammals, ranging from the vagrant shrew and Trowbridge's shrew to the Sonoma chipmunk, western gray squirrel, opossum, and black-tailed deer. Spotted owls feed primarily on dusky-footed wood rats, known for their large wood pile nests. Carnivores include the raccoon, striped and spotted skunks, long-tailed weasel, gray fox, and the recently returned river otter. Bats are always an intriguing group, instilling awe into those who admire and fear them. Nine different species have been identified roosting in the fire scars of old growth redwood trees. Three of the species, the Pacific western big-eared bat, fringed myotis, and Yuma myotis, are federal or state species of concern.

Isolated coastal rocks and beaches serve as haul-outs for harbor seals and California sea lions. Although Bay shores were once filled with pinipeds, concetrations such as the hundreds of harbor seals that haul out in Point Bonita Cove at Marin Headlands can still be found. Significant harbor seal pupping areas are found in Bolinas Lagoon and Tomales Bay. The northern elephant seal population has been rapidly increasing, leading to more encounters on sandy beaches throughout the region, including a fairly large colony at Point Reyes National Seashore. California gray whales, humpback whales, and harbor porpoises use nearshore waters. Young whales occasionally wander into San Francisco Bay. Southern sea otters are infrequently seen offshore with numbers increasing as the population spreads north from Monterey Bay.

Insects, Spiders, Centipedes, Millipedes

Golden Gate is simply teeming with insects, spiders, and other many-legged crawlers. Every habitat has its crew of characters, from bugs thriving in the tops of tall trees, to soil dwellers milling beneath the earth's surface. The sight of early morning dew on a spider web, or a bumble bee lumbering from flower to flower, or a centipede crawling through leaf litter can be an introduction to an entirely new world. Social insects such as ants, bees, and wasps are often introduced species from other parts of the world, but native representatives still thrive in the park. Grasshoppers jump in front of visitors in the grasslands, and beetles trekk across the sand dunes. Even the fly, a creature we often think of as ugly, comes in a rainbow of colors and can be seen pollinating flower clusters in the spring. Bugs even show up in wetland areas, water striders gliding across a creek surface, or dragonflies and damselflies alighting on a sedge. There are as many insects to learn as the visitor has time to explore.

The most beautiful insects of the park are no doubt the butterflies. In late spring and early summer, the iridescent wing scales catch the visitor's eye as they move from flower to flower spreading pollen. Grassland wildflowers attract the majority of species, but butterflies abound in any of the park's ecosystems. At least 44 species of butterflies occur in the Marin Headlands and 34 species occur at Milagra Ridge, inlcuding species of skippers, swallowtails, hairstreaks, blues, ladies, admirals and crescents. Such high species diversity illustrates the importance of habitat fragments within largely developed landscapes.

Endangered Fish

The threatened steelhead trout is found in many perennial coastal streams within the park. In addition, the offshore waters along the Pacific coast as well as estuarine areas in San Francisco Bay and Tomales Bay provide rearing habitat for steelhead. Threats to this species include degradation of spawning gravels, habitat simplification, and water diversions.

The threatened coho salmon is in its southernmost range in the Lagunitas, Olema, and Redwood Creek watersheds. Juveniles are often found in deep pools with abundant cover in the form of undercut banks, overhanging vegetation, and woody materials. In addition, the offshore waters along the Pacific coast as well as estuarine areas in Tomales Bay could provide rearing habitat for coho salmon. Threats to this species include degradation of spawning gravels, habitat simplification, and water diversions.

The endangered tidewater goby currently lives in Rodeo Lagoon and at Joacomini Ranch in the north lands near Point Reyes. Historic records indicate that the small estuarine fish occurred in at least 9 other locations within the San Francisco Bay Region, such as Lake Merced and Corte Madera Creek. Threats to this species include loss of habitat through excessive sedimentation, poor water quality, and non-native competitors.

Endangered Butterflies

The endangered mission blue butterfly inhabits Milagra Ridge in Pacifica, Sweeney Ridge in San Bruno, Twin Peaks, and portions of the Marin Headlands. One of the first invertebrates to be protected under the Endangered Species Act, this small butterfly is an important component of area grasslands. Its host plant is silver-leaf lupine, and it is only in its mature flight stage for three weeks. Several butterfly habitat restoration projects are currently underway in the park involving non-native plant removal and native plant restoration. Threats to this species include development, trampling by excessive foot traffic, illegal off-road vehicles, and non-native plant invasion.  

The endangered San Bruno elfin butterfly occurs at Milagra Ridge and Montara Mountain near Pacifica, San Bruno Mountain in San Francisco, and near Alpine Lake and Dillons Beach in Marin County. Its host plant is stonecrop. Young larvae are tended by several species of ants that protect them from predators. These ants also groom the larvae and feed on a honeydew substance produced by the larvae.  Threats to this species include non-native plant invasion, trampling by people, lack of proper fire management, and development.

The Bay checkerspot butterfly inhabits Edgewood Park in the San Francisco Watershed. It has a wing span of little more than 2 inches. The forewings have black bands along all the veins on the upper surface, contrasting sharply with bright red, yellow and white spots. Their habitat is on serpentine soild where their host plant, dwarf plantain, grows. Males typically emerge four to eight days before females. Males can mate many times, while most females mate only once. Threats to this species include development and non-native plant invasion.

Fish

Golden Gate National Recreation Area cannot escape the influences of the ocean and bay waters that surround it. Notice the fisherman on park beaches or piers, and you will begin to realize the bounty of fish in the park. Starting from the offshore waters of the Pacific ocean, a multitude of species travel along currents past and through the Golden Gate. The SanFrancisco Bay is a world of its own, supporting estuarine species that can handle the fluctuating salinity levels. Intertidal areas of the park provide important spawning and rearing habitat for fish.

Commercially important species such as the Pacific herring spawn in Tomales Bay, the intertidal rocks of Alcatraz, and other central bay rocky shorelines. Anchovy are the most abundant fish in the Bay, entering seasonally to forage and spawn, and are important to the economy of West Coast fisheries. 

The intertidal zone supplies fishermen with surf perch, cabezons, blennies, rock fish, pricklebacks, mussels and sea urchins. Typical estuarine fish include brown smoothhound, pile surfperch and white croaker. Coho salmon, lamprey, steelhead trout and maintain their annual migrations up Redwood Creek, Olema Creek and Lagunitas Creek. Green and white sturgeon can still be found in lower Lagunitas Creek, Tomales Bay, and the San Francisco Bay-Estuary. Limited information about fish species and abundance is available from beach seines and trawls conducted by the California Department of Fish and Game.

Nonnative Animals

Non-native animals are often introduced to an area as hunting stock for pioneers settling an area. Others like rats were brought over by accident in the hulls of ocean-crossing ships. Invasive animals tend to be generalists that compete with local wildlife for food and territory. They can also be a threat to local vegetation if they overforage in delicate habitats. Sometimes invasive wildlife need to be removed from parklands.

A number of birds have become park pests. Brown-headed cowbirds parasitize open-cup nests of birds. Neotropical migrants and riparian nesting birds are particularly susceptible. Cowbird parasitism is widespread throughout the park, but the level of parasitism and the lack of concentrated foraging areas make cowbird control unrealistic. Neotropical migrants are threatened by elevated predation levels (probably resulting from habitat modification), loss of habitat and parasitism. Wild turkeys were recently introduced into Marin County by the CDFG. Wild turkeys feed on a wide variety of foods including native frogs and native plants and seeds. Peacocks have similar habitat impacts. European starlings are cavity nesters that compete with and displace native species from limited nesting habitat. American kestrels, bank swallows and other cavity nesters are impacted by the widespread occurrence of starlings.

Feral hogs were widespread in the park during the 1980s but appear to have been successfully eradicated through hunting and trapping efforts by the NPS. Only a few unconfirmed sightings have been reported over the past 5 years. Feral hogs have potential to seriously degrade habitat and native animals populations through soil disturbance, uprooting of native plants, competition for foraging resources, particularly acorns, predation on small animals, and disease transmission. Feral hog populations could rapidly increase again at any time in Marin or San Mateo counties.

Norway and black rats are known to occur in various locations throughout the park, including Muir Woods, Alcatraz, Olema Valley and Marin Headlands. Rats prey on native wildlife and their young. They were found preying on the Townsend's big-eared bat in Olema Valley, where steps were taken to discourage and exclude them from the maternity roost. They are also a threat to burrow-nesting birds (such as pigeon guillemots on Alcatraz) that leave their young unattended while the adults forage at sea. Black rats are excellent climbers and will take eggs and young out of nests in tall shrubs and trees. Rats also carry diseases and constitute a human health threat wherever they occur.

A major threat to aquatic systems is the bullfrog. It is found in inland lakes, ponds, and wetlands such as Big Lagoon. It is a treat to local amphibians, eating the eggs and juveniles of other frog species, including the endangered red-legged frog.