Stop 1: San Miguel Island Tour

Aerial view showing San Miguel Island’s marine terraces.

Tim Hauf, timhaufphotography.com

Nowhere Else on Earth
Close to the mainland, yet worlds apart, San Miguel Island, along with the other Channel Islands, is home to plants and animals that are found nowhere else on Earth. As on the Galápagos Islands of South America, the isolation of the Channel Islands has allowed evolution to proceed independently, fostering the development of nearly 150 plants and animals endemic, or unique, to these islands. San Miguel Island is home to 20 of these species and some, like the San Miguel Island song sparrow, are found only on this island.

Isolation has also played a major role in shaping human activities on the islands. While the southern California coastal mainland has seen extensive development, the Channel Islands remain undeveloped. The islands' separation from the mainland by up to 60 miles of an often turbulent ocean has limited and directed human use and occupation for thousands of years. And this limited use continues today, giving us a chance to see coastal southern California as it once was.

So step back in time and experience San Miguel Island's isolation as you walk up Nidever Canyon to the ranger station. It's like nowhere else on Earth.

An Ocean Park and Sanctuary
From this vantage point, one has the opportunity to gaze upon another part of the park: the marine environment. One nautical mile of water around each island is part of Channel Islands National Park, and the six nautical miles around each island form Channel Islands National Marine Sanctuary.

Within this ocean realm, one often sees or hears California sea lions, northern elephant seals, or harbor seals. The island's isolated shoreline offers these pinnipeds an ideal combination of safety from predators and freedom from human disturbance, making the island an ideal place to rest, breed, and pup.

But even San Miguel Island's isolation could not always protect these and other sea mammals from human predation. As early as the late 1700's, fur hunters were exploiting sea otters, fur seals, elephant seals, and sea lions for their fur, hides and oil. Sea mammal hunting ended in the early 1900's and laws like the Marine Mammal Protection Act now protect these species.

In this isolated environment, their protected populations have recovered from centuries of slaughter. Today, up to five different species (elephant seals, sea lions, Guadalupe fur seal, northern fur seals, and harbor seals) and over 100,000 individuals use the island's shoreline. On Point Bennett alone over 30,000 individuals can be found-making it one of the largest concentrations of wildlife in the world.

These pinnipeds, along with over 800 other marine species, also depend on the extensive kelp forests found in these waters for food, shelter, and protection- from foraging nudibranchs, to grazing snails, to fish seeking refuge, to whales feasting on plankton. Kelp is a type of algae that, under ideal conditions (cold, nutrient-rich water), is one of the fastest growing organisms on Earth-it can grow two feet per day.

While urban and industrial development has altered much of the southern California coastal mainland, the isolated islands contain the most undisturbed stretches of coastline in this region, providing some of the best conditions for kelp forests and their inhabitants.

Kelp forests don't just benefit marine species-they benefit us as well. Not only do we eat some of the animals that depend upon the kelp forest, but everyday products like ice cream, salad dressing, and even toothpaste also use a little bit of seaweed as well. Kelp is harvested for a natural ingredient called algin, which is used as a suspending, stabilizing, emulsifying, gel-producing, and film-forming additive in more than 70 commercial products. In addition, marine plants and algae such as kelp provide Earth with 80 percent of its oxygen.

Despite these benefits, human activities have placed the kelp forest and its inhabitants in jeopardy. Pollution and over-harvesting of marine species have altered the kelp forest ecosystem, and kelp forests in southern California today cover less than half the area they covered at the turn of the 20th century.

However, with the establishment of marine protected areas (MPAs), improved pollution controls, fishing regulations, and increased research and public education, some of these problems have been corrected.

Within the park and sanctuary, this network of MPAs provides a refuge for sea life, as well as opportunities for recreation, education, and science. In 11 marine reserves (including three around San Miguel Island), recreational fishing and commercial harvesting are prohibited; limited fishing and harvesting are allowed in two marine conservation areas. The MPAs total 318 square miles, the largest such network off the continental United States and an important part of a larger, worldwide effort to conserve natural, historic, and cultural marine resources.

An Ideal Isolated Home
San Miguel Island and its associated islets support regionally important and diverse seabird colonies, including one-third of the breeding seabirds in the Channel Islands. Prince Island, which lies at the entrance to Cuyler Harbor, hosts the most diverse seabird colony on the west coast with 13 different species. Ashy storm-petrels, Brandt's cormorants, Cassin's auklets, pigeon guillemots, California brown pelicans, and common murres all make their home here.

San Miguel Island, the other Channel Islands, and all of their associated islets and offshore rocks comprise one of the largest breeding centers on the west coast for seabirds and shorebirds. Their isolation and freedom from predators and human disturbance, as well as the abundance of food in the cold, nutrient-rich ocean waters surrounding them, make them an ideal place for marine birds to breed and rear their young.

However, the island's isolation was not able to protect some species of seabirds from human impacts. The destruction of native vegetation, importing of non-native species, gathering of eggs, disturbance of rookeries, and the spread of pesticides in the marine environment have all been detrimental.

During the 1960s, the pesticide DDT nearly caused the extinction of the California brown pelican as a breeding species on the west coast of the United States. In 1970, only 552 nesting attempts were made on Anacapa Island (the largest colony on the West coast of the United States) and just one chick survived. On October 13, 1970, the brown pelican was listed as an endangered species.

Today, pelicans and other seabird species are gradually recovering now that their isolated island home is protected within Channel Islands National Park. Through monitoring and restoration programs, the park and its partners are working to conserve critical nesting habitat and to protect the integrity of the island and marine ecosystems that support 90 percent of southern California's seabird populations.

On San Miguel Island, these efforts have focused on restoring seabird nesting habitat, removing black rates and nonnative vegetation, revegetating with native plants, installing nest boxes, and closing areas to protect nesting seabirds.
The most notable results of these efforts have been the successful recovery of the California brown pelican and its removal from the endangered species list in 2009.