Introduction
A few years ago, while working on a CIR habitat restoration project on San Nicolas Island, I noticed that the songs of Western Meadowlarks that I was hearing were noticeably different than those of their counterparts on the mainland (Gevirtz personal observations 2018, 2019). This led me to wonder whether the different songs are distinct local dialects or indicators of distinct subspecies.
Western Meadowlark (Sturnella neglecta) is one of the most abundant and widely distributed grassland birds, inhabiting open grasslands of the Northern Great Plains to the shore of the Pacific Ocean, and from sea level to mountain meadows (Davis and Lanyon 2008). However, the number of western meadowlarks is declining rapidly. In 1966, there were an estimated 57 million western meadowlarks in North America, but now the population is estimated to be only 30 million birds (Sauer et al. 2017). This represents a nearly 50 percent reduction in the population.
Although the Western Meadowlark was known to explorers Lewis and Clark, John James Audubon observed that Western Meadowlark had been overlooked as a distinct species, separate from Eastern Meadowlark, and gave the bird its Latin name (Sturnella neglecta) as it had been “neglected.” His report (Audubon 1844) of a meadowlark west of the Mississippi similar in appearance but differing in voice from Eastern Meadowlark (S. magna) triggered a debate over whether these were separate species that lasted for another century (Davis and Lanyon 2008).
Population Numbers and Trends
In coastal California, the breeding population has declined every year over the past 50 years (Sauer et al. 2017). The same is true in Santa Barbara County, the meadowlark population has also declined dramatically. On the south coast of Santa Barbara County, meadowlarks no longer breed here, but they still occupy grasslands in fall and winter on the San Marcos Foothills and a few other locations. On the Gaviota Coast, west of Goleta, meadowlarks are still present but are very uncommon and irregular breeders (Lehman 2020). They breed on San Miguel, Santa Rosa, Santa Cruz, Anacapa and Santa Barbara Islands (Collins and Jones 2015) and probably breed on San Nicolas and Catalina Islands.
We do not know whether Western Meadowlarks travel across the ocean between the mainland and the Channel Islands; nor do we know whether they travel from island to island (Paul Collins, pers. communication 2020). It may be that each island supports a population that has its own repertoire of songs. It may also be that each island population supports a distinct population of this species and that distinct song repertoires are indicators of distinct subspecies.
Western Meadowlark Singing
Western Meadowlark males sing on breeding grounds from their time of arrival in spring through the summer (Lanyon 1957). They have a complex melodious primary song that consists of 2 phrases: an initial series of 1–6 rather pure whistles, and a terminal phrase of 1–5 gurgling, steep slope elements. Males typically sing from perches, frequently along the perimeter of their territories, though they may also sing from the ground or from perches within their territories (Davis and Lanyon 2008).
Study Objectives and Questions
Funded in part by the UCSB Associated Students Coastal Fund and in part by CIR, I am conducting a study of Western Meadowlark songs on the Channel Islands and on the mainland of southern California. The hypothesis is that Western Meadowlark populations on each island have song repertoires that are distinct from those of their mainland counterparts and from repertoires of populations on other islands.
I suspect that distinct song repertoires may suggest that each island supports its own distinct population of Western Meadowlark, and they don’t travel from island to island or from island to mainland. I suspect that the island populations are isolated from each other and from the mainland population and that there may be one or more subspecies that have not been recognized.
Field Methods and Analysis
In summer 2021, I was assisted by three UCSB student interns and one UCLA intern who were a big help to me as it’s often good to have more than one observer since different people observe different things. Recordings of songs were made using a microphone and sound recorder.
We recorded songs on the Gaviota coast, on the edges of the Santa Maria Valley, on the Sierra Madre potreros, and on the Chimineas Ranch near the Carrizo Plain, and on Santa Rosa Island. Although we traveled to Santa Cruz Island in July, we did not find any singing. Next year, if I can find funding, I will record at additional island and mainland locations. Soon, I will begin analysis of the songs using software called Raven.
We did not collect enough recordings to make any conclusions, so additional recordings are necessary. Eventually, I hope to have enough songs to produce a paper that will document the results and present additional questions.
Funding Needed for Future Work
Funding is needed to support additional research.
If you can support this project, please contact me at elihu@cirweb.org.