Irrigated agriculture -- precious habitat for the long-billed curlew

April 16th, 2014
Despite the recent rainfall, California is still in a drought, so not only are water supplies limited, but demand for water is increasing from a variety of uses. In a recent study published by Point Blue Conservation Science (Point Blue) and Audubon California in the journal Western Birds, scientists document the importance of irrigated agricultural crops in California's Central Valley to a conspicuous shorebird. Crops like alfalfa provide critical habitat for the Long-billed Curlew, the largest shorebird in North America and a species of continental conservation concern. As the drought continues, mirroring conditions that are projected to be more common in the future, scientists say the need for allocating water reliably to wetlands and flooded agricultural lands will only grow stronger for wetland-dependent birds.

"Curlews can't survive in the Central Valley without irrigated agriculture, given the loss of most of their historic shallow-water habitats in summer and fall," says Dave Shuford, Point Blue ecologist and lead author of the publication.

The Central Valley's protected wetlands (federal wildlife refuges, state wildlife areas, and private lands) and certain types of agriculture (e.g. rice, alfalfa), provide nearly all of the habitat used by millions of ducks, geese, shorebirds, and other waterbirds every fall, winter, and spring. In early fall—the driest time of year in the Valley—it is especially important that these birds can find flooded fields and wetlands for their survival. In the study, Point Blue scientists, Audubon California, and a host of volunteers studied the curlews for three years. Observers recorded over 20,000 curlews: about 93% were in the central and southern portions of the Central Valley, concentrating in areas extensively flood irrigated for alfalfa and irrigated pasture.

"Millions of migratory birds rely on the flooded agricultural fields each year. Conservation and agricultural groups can work together to benefit birds and people," says Meghan Hertel, Audubon Working Lands Director.

In the future, irrigated agriculture will face increased water costs driven by competing needs of an increasing human population and probably drier conditions under a changing climate. These threats might be offset if a program of economic incentives can be devised for farmers to maintain flooding of crops, such as alfalfa and irrigated pasture, to the benefit of both farmers and curlews.

More information:
Shuford, W. D., G. W. Page, G. M. Langham, and C. M. Hickey. 2013. The importance of agriculture to Long-billed Curlews in California's Central Valley in fall. Western Birds 44:196-205.

Provided by Point Blue Conservation Science

This Phys.org Science News Wire page contains a press release issued by an organization mentioned above and is provided to you “as is” with little or no review from Phys.Org staff.

More news stories

Nepal to end rescue operation on trekking route

Nepal was wrapping up rescue operations in its northern mountains Monday, saying all the hikers believed to have been stranded on a trekking route by a series of deadly blizzards are now safe.

Viagra protects the heart beyond the bedroom

Viagra could be used as a safe treatment for heart disease, finds new research published today in the open access journal BMC Medicine. The study reveals that long-term daily treatment of Viagra can provide protection for th ...

Comet Siding Spring whizzes past Mars (Update)

A comet the size of a small mountain and about as solid as a pile of talcum powder whizzed past Mars on Sunday, dazzling space enthusiasts with the once-in-a-million-years encounter.

Head injury causes the immune system to attack the brain

Scientists have uncovered a surprising way to reduce the brain damage caused by head injuries - stopping the body's immune system from killing brain cells. The study, published in the open access journal Acta Neuropathologica Co ...

Mummy remains refute antiquity of ankylosing spondylitis

Ankylosing spondylitis is a systemic disease that causes inflammation in the spinal joints and was thought to have affected members of the ancient Egyptian royal families. Now a new study published in Arthritis & Rheumatology, a jour ...