I did a little research this morning.  A lot of birds from many different 
families are recorded as eating them.  One article alone, written in 1941 in 
Nevada, mentions the following species (in no formal order): turkey vulture, 
sharp-shinned hawk, red-tailed hawk, Swainson's hawk, rough-legged hawk (must 
have been spring before hawk headed north), golden eagle, northern harrier, 
merlin, American kestrel, sharp-tailed grouse, greater sage-grouse, ring-necked 
pheasant, burrowing owl, northern flicker, Lewis's woodpecker, western 
kingbird, horned lark, American crow, pinyon jay (Doug, please note), 
black-billed magpie, American robin, sage thrasher, American pipit, loggerhead 
shrike, house sparrow, western meadowlark, yellow-headed blackbird, red-winged 
blackbird, Brewer's blackbird, brown-headed cowbird, lark sparrow, fox sparrow 
and green-tailed towhee.

It is doubtful any of these birds are able to truly regulate huge Mormon 
cricket population upticks.  But they certainly include them in their diet 
opportunistically.  I suspect when sagebrush is a major food item of the 
omnivorous crickets (they eat basically all plants in their path, plus other 
insects including dead cohorts), the breadth of bird species eating them, and 
the number of crickets consumed per encounter would decrease.  Sagebrush 
contains some problematic chemistry.

The smaller birds that eat Mormon crickets are probably selectively consuming 
smaller individuals, mostly early-instar immatures, or just eating softer, 
juicier parts of the crickets that are easier to digest.

As for California gulls "saving the day" by eating all the Mormon crickets 
ravaging crops in 1848, yes, gulls of more than one species (but perhaps 
dominated by California gulls) did opportunistically respond to the insect 
invasion.  Did they have a big impact?  Probably not, but they tried and for 
that and the "fish story" that ensued which gets better with time, they will 
always be revered in the Great Basin.  One aspect of the 1848 "miracle of the 
gulls" that was apparently misinterpreted was the casting of pellets by the 
gulls.  Contrary to contemporary thinking that the gulls were regurgitating so 
they could eat more crickets and be more helpful, they were simply getting rid 
of excess undigestible chitin and other materials similar to all birds that 
produce pellets.  Cherry growers in the same region do not share warm fuzzies 
for California gulls, as they have a definite soft spot for cherries.

Dave Leatherman
Fort Collins

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