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January 2020.

Docents in two seasons

From about March to September, the nesting season, waterbird docents on Alcatraz Island are stationed near its colonial waterbird colonies. Their job is to show visitors the island's natural side. With spotting scopes and binoculars, visitors watch birds incubating eggs and feeding chicks, and the docents explain how the island's birds nest. People leave with a new appreciation for gulls, cormorants, herons and egrets.

Waterbirds are not the island's only birds, though. In the winter months, the same docents help Alcatraz biologist Tori Seher with island-wide bird counts. Twice a month, they walk 1.5 miles over 3 hours, counting every bird on Alcatraz and in the nearshore waters around it. The season's last count was set for January 31.

What they have seen

So far, species and numbers show no significant change from earlier years. Rare sightings this season included a golden-crowned kinglet, Bewick's wren, Wilson's warbler and Say's phoebe.

The island's peregrine falcon pair, which moved to Alcatraz the year before, keeps hunting — chasing off the odd red-tailed hawk, unsettling the western gulls, and sending the small resident flock of rock pigeons into hiding for a while. The most abundant winter birds, song sparrows and Anna's hummingbirds, seem unfazed by the predators and keep turning up in large numbers.

The counts are entered into eBird.

To learn more, or to become an Alcatraz waterbird docent, contact Tori Seher at Golden Gate National Recreation Area. More from the park's Bay Area Nature & Science Blog.

Sources

Based on "Alcatraz Waterbird Docents Assist with Island-wide Winter Bird Counts," National Park Service; a work of the United States government in the public domain. A misspelling in the source ("phased" for "fazed") is corrected.

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Licens: CC0 1.0 (offentligt eje) · Bearbejdet efter www.nps.gov

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