Alcatraz -- Nature

In 1972, Alcatraz became part of the Golden Gate National Recreation Area and is now managed by the National Park Service.  Protecting the ecology of Alcatraz Island is a very important part of the National Park Service's mission.

Salt-laden cold wind, rocky ground, and a scarcity of fresh water originally limited the number and types of plants on Alcatraz.  The island was covered with the thinnest of soil, which supported only sparse grass and a few shrubs.  The absence of predators, however, made Alcatraz a haven for birds, and they built nests and reared their young in great numbers.

When military development began in the mid-1800's, much of the rock blasted from the surface and sides of the island during the construction eventually came to rest at the shoreline.  This created tide pools that now provide homes for thriving populations of crabs, sea stars, and other marine animals.  In turn, these creatures improve the diet of many of the sea-going birds that are attracted to Alcatraz.

The army barged topsoil to Alcatraz from Angel island, piling it around gun emplacements.  This soft dirt provided a base for native California plants grown from seeds that came to the Island in the transported soil.  The military also planted a variety of shrubs and plants to keep the island's new surface from sliding or blowing away.  Over the years, inmate gardeners and the families of soldiers and correctional officers planted flowers and vegetable gardens, bushes, and trees.  After the prison was closed, the untended plants began to take over and have grown and spread at will.

Modern Alcatraz is an evolving ecological preserve.  The plants provide food and shelter for mice, slender salamanders, and insects, which, in addition to the plants themselves, attract birds.  Hawks, ravens, geese, finches, and hummingbirds are frequent visitors to the Island.  Western gull and black-crowned night heron colonies are so active that during breeding season, the National Park Service closes parts of the Island to human visitors to protect the birds and encourage their success.  Cormorants, pigeon guillemots, and black oystercatchers roost in more isolated sites on the Island's rocky cliffs.

Alcatraz Trivia:

Alcatraz has one of the largest western gull colonies on the northern California coast.

The only land mammal on Alcatraz – aside from human visitors – is the deer mouse.  The California slender salamander is the only amphibian.

The sharks that swim in San Francisco Bay and around the island are not "man-eaters."  Sand sharks are among the most common.

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Click on each of the topics below to read about the history of Alcatraz:

Alcatraz the Early Years -- Alcatraz the Fort -- Alcatraz the Prison --
The Native American Occupation -- Natural Alcatraz -- Alcatraz the Tourist Attraction

Click on each of the headings below to read about each of the major areas at Alcatraz:

The Dock -- Guardhouse and Sally Port -- Post Exchange - Officers' Club -- Military Chapel --  Barracks - Apartments -- Warden's House -- Lighthouse -- Cellhouse -- The Gardens

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For tickets and tours, contact Alcatraz Media at www.alcatraz.us,
or call 866-268-8729 or 415-461-4608.