What Kind of Fish to Pelicans Eat?


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A researcher releases a Strawberry Lake pelican after a stomach-content examination. Utah.gov

It’s an age-old battle: pelican versus trout angler. These gangly intruders are scooping up all of the fish, proper? Not so quick, says a team at Utah State College’s Quinney Faculty of Pure Assets researching predator-prey relationships between pelicans and cutthroat trout. Seems the winged pescatarians is perhaps serving to us catch extra fish. 

Strawberry Reservoir, a 27-square mile man-made lake southeast of Salt Lake Metropolis, is Utah’s hottest fishery. As a part of the state’s Blue Ribbon Fisheries program, it logs 1.5 million hours of fishing a 12 months, providing anglers ample alternative to catch prize cutthroat and rainbow trout and kokanee salmon. Its lore goes again to a catch in 1930, when, in accordance with the Utah Division of Wildlife Resources, Mrs. E. Smith caught the state document non-native cutthroat there weighing in at 26 kilos 12 ounces.

However migrating American white pelicans, which breed in Canada and the northwestern U.S. and winter in California, Mexico, and the Gulf Coast, additionally cease there to fish. And since cutthroat populations have fluctuated considerably within the reservoir in latest a long time, lead writer Phaedra Budy and her crew determined to research whether or not the pelicans had been responsible.

Whereas cutthroats are effectively established within the reservoir and its system of feeder streams, the inhabitants of grownup fish has ranged extensively over the previous twenty years, from 220,000 to 464,000. So, Budy’s crew captured pelicans over a two-year interval and studied the contents of their stomachs. They discovered the birds’ diets consisted of 85 % Utah sucker, 6 % Utah chub, and three % cutthroat trout. Throughout spawning runs, when squadrons of pelicans kind feeding “fences” that blockade the mouths of tributaries, the share of cutthroats consumed by the pelicans rose to 10 %. However on mixture, roughly 1 % of the reservoir’s grownup cutthroats had been taken by the birds, the analysis discovered.

“As a result of pelicans are extremely seen and congregate in massive numbers at Strawberry Reservoir, anglers assume that they’re consuming tons of trout,” said Frank Howe, a member of Budy’s crew. “However the research exhibits that pelicans are usually not focused on the identical fish species which might be prized by human anglers.” As a substitute, pelicans principally eat the native suckers and chubs, species whose populations have been on the rise and a priority for wildlife managers. So, Budy and her study conclude, the pelicans are doubtless doing anglers a favor by eradicating competing native fish.





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