Gulf of the Farallones & Cordell Bank National Marine Sanctuaries Data Exercise

The Gulf of the Farallones National Marine Sanctuary encompasses 1,235 square miles of nearshore and offshore waters and seabed off the eastern Pacific. It includes nursing and spawning grounds for commercially valuable species, at least 26 species of marine mammals and 15 species of breeding seabirds. Located just a few miles north of cosmopolitan San Francisco, it is north of and contiguous with the Monterey Bay National Marine Sanctuary in Central California.

The adjacent Cordell Bank National Marine Sanctuary is a submerged seamount. The prevailing California Current flows southward along the coast, and the upwelling of nutrient-rich, deep ocean waters in the sanctuary stimulates the growth of organisms at all levels of the marine food web. The sanctuary was named for Edward Cordell of the U.S. Coast Survey, who mapped it in 1869. The granite formation ranges from 50 to 200 meters in depth and is almost 22 miles west of Point Reyes, California. It is unknown how many shipwrecks, if any, lie on the floor of the Cordell Bank National Marine Sanctuary. The depth of the sanctuary and its distance from shore have made it difficult to conduct surveys of the area.

The waters of the Gulf of the Farallones National Marine Sanctuary have witnessed a rich diversity of watercraft, and over 140 shipwrecks have been reported in this region. Most of the maritime activity in the last 400 years has been focused on trade. The Spanish built missions around the Bay after 1776, which brought supply ships and foreign fur traders. Following Mexico's independence from Spain in 1821, the port of Yerba Buena (later named San Francisco) gradually expanded into a regional trading center. New England's "Yankee Traders" and ships of European nations traded, whaled, and gathered furs and hides while using San Francisco as a base to re-supply their vessels.

The Farallon Islands and the mainland coast north of the Golden Gate have historically provided hazardous navigational obstacles to shipping. Year-round fogs and dangerous winds and storms often led ships to rocks and beaches to be pounded by the Pacific swells. Fierce currents have always swept in and out of the entrance to the Golden Gate. Many known shipwrecks litter the floor of the Gulf of the Farallones National Marine Sanctuary. The earliest recorded shipwreck in the sanctuary area was the Spanish Manila galleon, San Augustin, sunk in a gale while anchored in Drake's Bay in 1595.

Data Exercise

Part 1: Be a Shipwreck Detective

Go to the Sanctuary Charts page, and print out the chart for the Gulf of the Farallones and Cordell Banks National Marine Sanctuaries. (This requires Adobe Acrobat Reader. Click here to download this for free).

Go to the Gulf of the Farallones and Cordell Banks National Marine Sanctuaries Shipwreck Database, and plot the shipwrecks listed in the data table by placing a small x and the shipwreck's name at the spot on the map where the latitude and longitude intersect.

1. Are there certain areas within your sanctuary that seem more prone to shipwrecks than others? Can you think of any reasons why this may be the case?
2. Are there certain times of year when there seemed to be more shipwrecks reported? Can you think of any reasons why this might be the case?
3. How many shipwrecks were reported in your sanctuary before 1942? How many were reported after 1942? Can you think of any reason for this difference?

Tips & Tools Other Bridge pages with related information:

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