{"pk":62902,"title":"Status and Trends of Breeding Ardeidae in the San Francisco Bay Region","subtitle":null,"abstract":"Abstract: Monitoring species abundance is a critical tool for identifying trends in wildlife populations. Using data collected in the San Francisco Bay Area between 1995 and 2019, we evaluated trends in nesting abundance of four Ardeid species across the entire study area and in 10 subregions, while accounting for the effect of rainfall. Overall, Great Egret (\nArdea alba\n) nest abundance increased by 27% (95% confidence interval -1%, 54%) from 783 to 993 nests. Great Blue Heron (\nArdea herodias\n) and Snowy Egret (\nEgretta thula\n) nesting abundance was similar across the study period, averaging approximately 503 and 509 nests, respectively, but Snowy Egret abundance was highly variable between years. Finally, Black-crowned Night-Heron (\nNycticorax nycticorax\n) abundance declined -22% (95% confidence interval -59%, 15%) from 682 to 535 nests. At the subregional scale, trends were variable within species, and no species had consistent positive or negative trends across all 10 subregions, although it appears the distribution of all species except Great Blue Heron shifted among subregions. Our results suggest conservation action may be warranted to recover the Black-crowned Night-Heron population in our study area, but there is uncertainty on the magnitude and the reasons for their decline. Further investigation of the mechanisms for demographic change is needed to guide effective actions. In the absence of that mechanistic information, protection of the few colony sites occupied by Black-crowned Night-Herons and Snowy Egrets, especially islands in San Francisco Bay and two large urban colonies in Santa Rosa and Fairfield, is a prudent immediate action.","language":"en","license":{"name":"Creative Commons Attribution 4.0","short_name":"CC BY 4.0","text":"Attribution — You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.\n\nNo additional restrictions — You may not apply legal terms or technological measures that legally restrict others from doing anything the license permits.","url":"https://creativecommons.org/licenses/by/4.0"},"keywords":[{"word":"abundance trend, Ardea alba, Ardea herodias, Black-crowned Night-Heron, Egretta thula, Great Blue Heron, Great Egret, Nycticorax nycticorax, Snowy Egret"}],"section":"Research Article","is_remote":true,"remote_url":"https://escholarship.org/uc/item/4202g2p6","frozenauthors":[{"first_name":"Scott","middle_name":"","last_name":"Jennings","name_suffix":"","institution":"Cypress Grove Research Center, Audubon Canyon Ranch, Marshall, CA 94940 USA","department":""},{"first_name":"Nils","middle_name":"","last_name":"Warnock","name_suffix":"","institution":"Cypress Grove Research Center, Audubon Canyon Ranch, Marshall, CA 94940 USA","department":""},{"first_name":"Emiko","middle_name":"","last_name":"Condeso","name_suffix":"","institution":"Cypress Grove Research Center, Audubon Canyon Ranch, Marshall, CA 94940 USA","department":""},{"first_name":"David","middle_name":"","last_name":"Lumpkin","name_suffix":"","institution":"Cypress Grove Research Center, Audubon Canyon Ranch, Marshall, CA 94940 USA","department":""},{"first_name":"Gabbie","middle_name":"","last_name":"Burns","name_suffix":"","institution":"San Francisco Bay Bird Observatory, Milpitas, CA 95035 USA","department":""},{"first_name":"Barbara","middle_name":"","last_name":"Wechsberg","name_suffix":"","institution":"Cypress Grove Research Center, Audubon Canyon Ranch, Marshall, CA 94940 USA","department":""}],"date_submitted":"2024-08-05T13:05:03-07:00","date_accepted":"2024-08-05T13:05:03-07:00","date_published":"2024-09-11T00:00:00-07:00","render_galley":null,"galleys":[{"label":"","type":"pdf","path":"https://journalpub.escholarship.org/jmie_sfews/article/62902/galley/48588/download/"}]}