Cabrillo National Monument - Ecosystem

Cabrillo National Monument by National Parks Service

Because Cabrillo National Monument (NM) is located on a peninsula, its natural features encompass terrestrial and marine ecosystems. From the 129-meter (422-foot) ridge of the peninsula down to the San Diego Bay on the east and the Pacific Ocean on the west one can see the scrubland habitat. The scrubland on Point Loma includes four community types: southern coastal bluff scrub, maritime succulent scrub, Diegan coastal sage scrub, and southern maritime chaparral. These communities are home to a variety of plant species such as snake cholla, prickly pear cactus, Mojave yucca, Shaw's agave, California coast poppy, Indian paintbrush, California buckwheat, California sagebrush, and lemonade berry. These plant communities make up the coastal mediterranean ecosystem which supports a variety of southern California animal species such as velvet ants, scorpions, shrews, mice, lizards, snakes, red-tailed hawks, foxes, and coyotes.

The view from the monument attracts over one million visitors each year. To the east, the city of San Diego sprawls across the landscape. On clear days, coastal mountains can be seen: north toward the San Bernardino Mountains near Los Angeles (approximately 161 kilometers [100 miles] away), east toward the Laguna Mountains near the desert, and south toward the Sierra Juárez mountain range of Baja California, Mexico.

Descending the slopes, sandstone cliffs drop off into intertidal habitat that characterizes the western shore of the monument. The intertidal zone is where the land and sea merge. Here marine plants and animals are submerged during high tide and exposed to the sun and wind on the rocky reef during low tide. This ocean environment supports a tremendous diversity of plants and animals. During low tide, visitors can see limpets, crabs, sea slugs, snails, sea hares, fish, and octopi all interacting with each other and utilizing the plants for food and shelter. Past the intertidal zone is the subtidal zone; where the tides no longer expose a rocky reef. This zone is where larger fish, larger sea stars, and many types of sea urchins live. This is also where some marine plants grow much larger.

Inhabiting the subtidal zone, outside of Cabrillo NM's boundaries, is the kelp forest. This is a habitat where large marine plants (kelp) form tall "trees" making an underwater forest. The kelp helps support life in the deeper ocean. These plants are fed upon by sea urchins and abalone. Large fish and mammals also inhabit the kelp forest, eating the sea urchins and abalone.

The interaction between the land and the sea also provides for some foggy and overcast days. When warm air from the land meets cooler air over the cold water, a heavy marine layer develops which envelops the park.

Geologically, active fault lines influence Point Loma as they have for thousands of years. Diving deep into the earth's mantle from the ocean floor and land, the fault lines move in small increments producing new geologic formations. As a result of fault line movement (called plate tectonics), the Point Loma peninsula is gradually moving north.