California Gull –the most common southern Nevada gull

By BRUCE LUND

California Gulls charge through brine fly masses for food at Mono Lake in California.

Following up on last week’s article on the second most common gull in southern Nevada, the Ring-billed Gull; I wanted to devote this article to the one we are most likely to see, the California Gull.

As I wrote last week, these gulls are so similar – close in size at about 20 inches, both white-bodied with light gray wings and backs, both with black and white wingtips – that one has to get close enough to use their bill coloration to tell them apart: a red spot on the lower bill for the California Gull and a black ring encircling both bills for the Ring-billed gull. And this is for the adults; immature birds are much more difficult.

Since flocks of California Gulls are common on Lake Mead and other southern Nevada water bodies the year round, it seems that at least some should nest in our area. However, that is not the case. All are wanderers from breeding colonies including a few in northern Nevada at scattered locations as reported by the 2007 Atlas of the Breeding Birds of Nevada: Lahontan Reservoir, the Carson Sink, Pyramid Lake, Ruby Valley, and Virginia Lake with up to 15,000 nesting birds at most.

That may seem like a lot, but compared to major colonies farther north with hundreds of thousands of birds, California Gulls are token nesters in Nevada. They’re choosy in their nesting sites, requiring islands surrounded by water deep enough to prevent access by land predators such as coyotes.

Of course, there are potential nesting islands in Lake Mead (for example), so why doesn’t this bird nest here? I don’t know all the reasons why, but one is probably the lack of a reliably dense insect food supply around their spring nesting time.

Of course, most of us associate gulls with the sea and assume they mainly eat fish. This is reinforced by numerous television programs showing massive gull breeding colonies by the sea and hordes of gulls following fishing boats and pestering beach-goers from Cape Cod to Myrtle Beach. However, the California Gull is one of a number of mainly inland species with its natural breeding range centered across the northern tier of United States from Montana to North Dakota and up into the prairie regions of Alberta and Saskatchewan. These are hardly fish-rich localities – but they do have lots of big insects.

Which brings me to the famous story of Mormons and “sea gulls”.

As soon as the original Mormons started settling on the shores of the Great Salt Lake in 1847, crops were planted. As fortune would have it, the winter was relatively mild. Many of the plantings survived the occasional frosts and the food outlook was promising going into the spring of 1848.

However, while the mild winter was good for crops, it was also good for the Mormon Crickets over-wintering in the soil. Emerging en masse and hungry in late May, the insect horde started devouring every plant on the landscape, including the Mormon crops. Then in early June, various Mormon diaries recorded the arrival of flocks of “sea gulls” descending upon and devouring the crickets to save the harvest.

Considering the scarcity of ornithologists in the American West in 1848, exactly which “sea gull” saved the Mormons’ crops was a matter of differing opinions for many years. Some were sure it was the Herring Gull, however subsequent bird research knocked this one from contention as the nearest Herring Gulls in the mid-1800s were thousands of miles away in their North Atlantic home range.

While a number of other gull species were proposed over time, ornithological detective work showed that California Gulls 1) had established nesting colonies on islands in the Great Salt Lake at the time the Mormons arrived and well before, 2) utilized large insects as a major food item, and 3) that gull nesting was timed to coincide with the natural emergence of large and nutritious crickets, grasshoppers, and other natural prairie insects for both young and adults.

This is not to diminish the mystery and miraculous arrival of the gulls as understood and interpreted by the Mormons in 1848. The flocks of “sea gulls” played a major role in saving crops that spring and it mattered not which gull it was that played that role.

Various Utah and Mormon websites relate how this gull story grew to become known as the “miracle of the seagulls” over the years. In commemoration the LDS Church erected the 15 foot tall Sea Gull monument in Temple Square in 1913 depicting two gulls eating crickets. Thirty-two years later in 1945, the “sea gull” was designated as the Utah State Bird.

I’ve often seen gulls nabbing insects in pastures and meadows, but it wasn’t until I visited Mono Lake in California that I was able to get photos of California Gulls gorging on brine flies. While the flies aren’t large in size, they are incredibly dense and gulls simply open their beaks, charge through the fly masses, and scoop them up by the score.

Similar brine fly masses occur on the shores of the Great Salt Lake where Californian Gulls add them to their menu along with Mormon crickets and miscellaneous grasshoppers which they continue to seek and eat to this day.

Bruce Lund is a retired biologist and has a lifelong love of nature instilled by his grandparents and some remarkable teachers. He has lived with his wife, Flo, in Moapa since 1997.

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