Using historic data to understand the shrinking pollinators of the endangered salt marsh bird’s beak (Chloropyron maritimum subsp. maritimum)

Authors

Denise A. Knapp, Santa Barbara Botanic Garden, 1212 Mission Canyon Road, Santa Barbara, CA 93105Follow
Stephanie M. Calloway, Eldorado National Forest, 2480 Carson Road, Placerville, CA 95667Follow
Sarah Cusser, Santa Barbara Botanic Garden, 1212 Mission Canyon Road, Santa Barbara, CA 93105Follow

Abstract

The salt marsh bird’s beak (Chloropyron maritimum subsp. maritimum) is an endangered plant thought to be dependent on large-bodied pollinators for effective pollination and reproduction. Thirty-three years after an initial survey (Lincoln 1985), we returned to the Naval Base Ventura County, California, to repeat surveys and quantify changes in the C. maritimum subsp. maritimum pollinator community. We found similar pollinator abundance, richness, and nesting preference in both years. However, in terms of pollinator composition, we found significantly different communities—those found in 2017 being composed of pollinators with significantly smaller bodies (i.e., shorter intertegula distances [mm]) than those found in 1984. We hypothesize that changes in pollinator size are the result of differential persistence of the pollinator community and may have significant effects on the rare plant’s reproduction. While ramifications could be substantial, anecdotal evidence suggests that smaller-bodied bees may also serve as adequate pollinators of C. maritimum subsp. maritimum. Future work will quantify changes in reproductive output.


Chloropyron maritimum subsp. maritimum es una planta en peligro de extincion que se cree que depende de polinizadores de gran tamano para una polinizacion y reproduccion eficaces. Treinta y tres anos despues de un studio inicial (Lincoln 1985), regresamos a la base naval del condado de Ventura, California, EE.UU., para repetir los estudios y cuantificar los cambios en la comunidad de polinizadores de C. maritimum subsp. maritimum. Encontramos una abundancia, riqueza y estrategia de nidificacion de polinizadores similares en ambos anos. Sin embargo, en terminos de composicion, encontramos comunidades significativamente diferentes; las encontradas en 2017 estaban compuestas por polinizadores significativamente mas pequenos que los encontrados en 1984 (es decir, menor distancia intertegular [mm]). Nuestra hipotesis es que los cambios en el tamano de los polinizadores son el resultado de la persistencia diferencial de la comunidad de polinizadores y pueden tener efectos significativos en la reproduccion de esta planta rara. Aunque las ramificaciones podrian ser sustanciales, pruebas anecdoticas sugieren que las abejas de cuerpo mas pequeno tambien pueden servir como polinizadoras adecuadas. Futuros trabajos podrian cuantificar los cambios en el rendimiento reproductivo.

Recommended Citation

Knapp, Denise A.; Calloway, Stephanie M.; and Cusser, Sarah (2024) "Using historic data to understand the shrinking pollinators of the endangered salt marsh bird’s beak (Chloropyron maritimum subsp. maritimum)," Western North American Naturalist: Vol. 83: No. 4, Article 7.
Available at: https://scholarsarchive.byu.edu/wnan/vol83/iss4/7