Miracle of the gulls

The miracle of the gulls is an 1848 event often credited by Latter-day Saints ("Mormons") for saving the Mormon pioneers' second harvest in the Salt Lake Valley. According to accounts, seagulls miraculously saved the 1848 crops by eating thousands of insects that were devouring their fields. The first crop was planted in 1847 just a few days after they entered the valley, which was very late in the growing season and produced a meager but utilizable harvest. The following spring, using seed from the first harvest, they planted their second crop, only to watch in dismay as the crickets attacked. Less than two years prior in October 1846 many of them were saved by quail that flew into their camp, on their trek to the Great Salt Lake and made available as food.

After Brigham Young led the first band of Latter-day Saints into what is now Salt Lake City, Utah, the pioneers had the good fortune of a relatively mild winter. Although late frosts in April and May destroyed some of the crops, the pioneers seemed to be well on their way to self-sufficiency. Unfortunately, swarms of insects appeared in late May.

These insects, now called "Mormon crickets" because of this incident, are not true crickets, but instead belong to the katydid family. Having ornamental wings, they are unable to fly, but instead can travel in huge swarms. Mormon crickets eat all plant material in their path, but they also cannibalize any insects that die on the way, including their own species. They are known to cyclically swarm in some areas of the Mountain West, especially in Utah and Nevada. These insects threatened the livelihood of the Mormon pioneers; stomping on the pests did not dissuade them from entering farms as others would advance. This is a reproductive strategy similar to mast reproduction in oaks, overwhelming predators with sheer numbers allowing a percentage of the population to survive to reproduce. Mormons often cast this disaster in Biblical terms like the 8th plague of locusts.

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