Map of the Heronries

The Regional Observation Periods for 2023

March 3–5 (Friday–Sunday)

March 18–20 (Saturday–Monday)

Mar 31–Apr 2  (Friday–Sunday)

May 6–May 8  (Saturday–Monday)

June 2–4   (Friday–Sunday)

June 17–19 (Saturday–Monday)

For more information:

Emiko Condeso

Ecologist/GIS Specialist

Cypress Grove Research Center

[email protected]

Map of the Heronries

Heron and Egret Project observers can use the map below to help plan their colony site visits. The colony status (active, inactive) reflects what was observed in the previous nesting season (2021).  The location of the colony marker (“pin”) is at the approximate center of the nesting colony.  Please let us know if this location should be corrected.

Visit with caution

If you choose to visit a heronry, please use caution. Please note that birds are especially vulnerable to disturbance during the nesting season (approximately February-June). During this time, please take care not to walk near or under the heronries, and always respect private property.

For more information about the heronries of the San Francisco Bay Area please see our publication: the Annotated Atlas and Implications for the Conservation of Heron and Egret Nesting Colonies in the San Francisco Bay Area or contact the Cypress Grove Research Center at 415.663.8203.

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