Living along an Urban River: Birds of the San Lorenzo River

White-crowned x golden-crowned sparrow hybrid. Photo taken at the San Lorenzo River mouth, Santa Cruz, California. Photo courtesy of and ©  John Garrett.

White-crowned x golden-crowned sparrow hybrid. Photo taken at the San Lorenzo River mouth. Photo courtesy of and © John Garrett.

The San Lorenzo is the largest (and possibly the most beautiful) watershed in Santa Cruz County, spanning 135 square miles. The last stretch of the river with predominantly fresh water (little to no seawater influence) runs from the Highway 1 bridge to the Water Street bridge. This section of the urban river is home to a host of unique plant species including California sycamore, creek dogwood, and thimble berry.The generous populations of trees and shrubs in this section of the San Lorenzo River provide for a variety of beautiful bird species.

Song Sparrow. Photo courtesy of

Song sparrow. Photo by Factumquintus.

Sparrows and finches are among the most numerous birds. Song sparrows and house finches nest in the shrubs and trees along the banks all year round. Other year-round residents include black phoebes and swallows which often build nests on the nearby bridges.

House finch. Photo courtesy of

House finch. Photo by John Benson.

The violet green swallow, cliff swallow and the rough-winged swallow are cavity nesters meaning they build mud nests on bridges or buildings. They also dig holes along the muddy riverbank to nest in. Swallows are most commonly seen during their breeding season which spans late March to July.

Violet Green Swallow. Photo courtesy of

Violet green swallow. Photo by Alan Vernon.

Read the rest of the story to learn who seasonal winter visitors include and to hear some cool bird songs here at MobileRanger.com.

Take the Self-Guided Mobile Tour

This piece is part of a tour all about the lower San Lorenzo River by the Coastal Watershed Council. You can download the free app with many tours of the Santa Cruz area and beyond at www.mobileranger.com.

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Julia Gaudinski


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