• San Elijo Lagoon Ecological Reserve
  • San Elijo Lagoon Ecological Reserve


1.5 miles, out-and-back




Del Mar, CA 92014, USA

San Elijo Lagoon Ecological Reserve

About this trail

It’s all about the birds, but to find the birds, you need to find the plants they love being around. The San Elijo Ecological Reserve hosts more than 250 species of shore and water birds in part because they are attracted to the multiple plant communities found here, which include coastal sage scrub, salt marsh, and riparian. It's a beautiful area to learn about the differences found in each of these plant communities and to see how one transitions into another.

From the trailhead overlooking the large flat expanse of the lagoon, head down the slope to the right into a shady area of tall willows and western cottonwoods. Behind a bench on the right, a large brown lump on the hillside is the exposed root of wild-cucumber. You'll find plenty of plants here. Coastal deerweed, monkeyflower, bedstraw, California encelia, coreopsis, and look for wild snapdragon mixed in with California buckwheat and blue elderberry. Other plant species you’ll see along the way are typical coastal sage scrub plants including lemonadeberry, toyon, California sagebrush, black sage, laurel sumac, and arroyo willow.

After about 0.25 miles, the trail turns left, and sage scrub gives way to an open flat area closer to small channels. The trail loops back inland to higher, drier ground. Turn right at the main trail to return to your car, or for a longer hike, go left toward I-5. Pay attention to the dense vegetation near the freeway and have your binoculars at the ready. You might hear the California gnatcatcher or, in summer, least Bell’s vireo. As you return, enjoy the view of the steep, north-facing slope of the lagoon, covered in spots with dense chaparral as well as tenacious non-native orange nasturtium.

Finally, look for the San Elijo Nature Center across the lagoon on Manchester Avenue. Another trail beyond a metal gate leads down past saltbush plants to an observation area level with the lagoon. This is a favorite spot for birders, so be sure to bring your binoculars.

We’ve rated the difficulty for this hike easy, with minimal elevation gain. Before you go, check to ensure the trail is open. More detailed information about the area can be found at San Elijo Lagoon Ecological Reserve.

What you’ll see

You’ll find tons of plants and plenty of birds that love them, so make sure to grab your binoculars. Take notice of the wildlife that changes along with the different plant communities, which shift dramatically with minimal changes in elevation.

Toward the water, salt marsh plants like spiny rush, pickleweed, salt grass, and alkali-heath dominate. Endangered bird species like Belding’s savannah sparrow (Passerculus sandwichensis beldingi) and the light-footed Ridgway’s rail (Rallus obsoletus levipes)—known as the light-footed clapper rail for many years—inhabit the marsh. With the elimination of 75% of southern California salt marsh areas, the breeding area for Belding’s savannah sparrow is limited. It is distinguished from other sparrows by a yellow patch in front of each eye. The light-footed Ridgway’s rail has seen more than 90% of its needed coastal wetland areas eliminated, with degradation continuing. There is concern about its low genetic diversity and interchange with isolated populations.

Watch for mullets (Mugil cephalus) jumping out of the water. During the fall and winter migration, shorebirds and ducks explore the mud or shallow water for tiny crustaceans. Terns dart overhead, white-tailed kites (Elanus leucurus) hover over the marsh, ospreys (Pandion haliaetus) make their rounds, and great blue herons (Ardea herodias) stalk their prey.

Great blue herons are large blue-gray birds yet weigh only about 4.5 to 5.5 pounds, thanks in part to their hollow bones. As stalkers, great blue herons often stand motionless in the water, waiting for their next meal to swim by before quickly stabbing it with their sharp beak. These birds are able to hunt both day and night, with night vision enabled by the high percentage of rod-type photoreceptors in their eyes. The snowy egret (Egretta thula) is another prey-stalking bird you may see. Slender birds, their brilliant white plumage makes them stand out. The especially long and wispy plumage on their backs, necks, and heads is produced during the breeding season. These feathers were once prized in the fashion industry, particularly for hat plumes, and hunting decimated the population. It started recovering in the 1930s with the passing of laws protecting the birds. Other birds with brilliant white plumage that you may see include the great egret and the juvenile little blue heron.

In recent years, Lagoon Conservancy volunteers have removed non-native castor bean plants, and consequently, the native blue elderberry (Sambucus nigra subsp. caerulea) is now more abundant. Kumeyaay ancestors used this plant to make a variety of things from musical instruments to fire drills to bows. Berry juice was used as a dye for basket making. Blue elderberry fruit is also a favorite food source for many bird species. The fruits ripen in the late summer and turn a deep bluish-purple to black color, which is often masked by whitish powder. The fruit is used to make jams, jellies, syrup, and wine. This species is widespread and can be found from San Diego’s coast up into the mountains and all across the western United States, southwest Canada, and northern Mexico.

While on the trail, take special care to listen for the California gnatcatcher (Polioptila californica californica), listed as threatened by the U.S. Fish and Wildlife Service, or the least Bell’s vireo (Vireo bellii pusillus), which is listed as endangered.


From I-5 go west on Lomas Santa Fe Drive for 0.9 mile. Turn right onto North Rios Avenue. Go 0.8 mile. Park at the end of the road. GPS: N33.00367, W117.27247

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Looking for more great hikes? Check out our Canyoneers page or purchase the book, Coast to Cactus: The Canyoneer Trail Guide to San Diego Outdoors.

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