Why Is Suet Used in Birdfeed?

By: Melanie Radzicki McManus  | 
 young Eurasian blue tit
This young Eurasian blue tit enjoys feeding on a suet cake hanging from a bird feeder. ARTERRA/Universal Images Group via Getty Images

Americans love birds. More than 57 million U.S. households set out bird food in their yards, hoping to help our fine feathered friends while being able to admire them up close. And one of the top bird foods purchased is suet.

Suet is a hard, white fat that forms around the kidneys and loins in cattle and sheep. Until the mid-20th century, the British regularly used suet in savory puddings, dumplings and pies, as it adds lightness and fluff to various dishes (similar to shortening in the U.S.) But in America, suet has typically been sold as bird food, specifically suet cakes.


Suet cakes are sold either as blocks of pure suet or a combination of suet and other favorite bird foods, such as peanut butter, cracked corn and birdseed. A wide variety of birds enjoy chowing down on suet, especially woodpeckers, nuthatches, chickadees, robins, jays and starlings. It's great for them, too, as suet is a high-energy food that birds can easily digest and metabolize. Therefore, it's especially helpful to set out suet in the spring and fall, when birds are expending a lot of calories migrating. Winter is another good choice, as the birds' other food sources will dwindle.

"Suet is most valuable in colder locations, whether that means high latitudes or high elevations," says Emma Greig, head of The Cornell Lab of Ornithology's Project FeederWatch, in an email interview.

Beware of using suet to feed the birds if you live in a warm locale. When the temperature rises above 70 degrees F (21 degrees C), suet melts and can become rancid. Melting suet can also coat birds' belly feathers, which can be dangerous to their survival.

If you decide to purchase suet for the birds, one of the easiest ways to use it is to smear it on a log or tree branch. The downside to this is that other critters, such as squirrels, rats, skunks and even bears, may eat it first. A more practical idea is to place the suet cake in a mesh bag or special wire cage, then hang it from a tree branch about 5 to 6 feet (1.5 to 1.8 meters) above the ground. The feeder should also be placed close to the tree trunk, as the birds most attracted to suet tend to cling to tree bark while looking for insects to eat. Another option, says Greig, is to mount the suet feeder on a pole with a squirrel baffle (a protective shield) which will effectively stop all mammals from getting it.

One final consideration when setting out suet is that starlings really love it. But starlings are considered a nuisance bird that often drive away native species. Sometimes these aggressive birds gather in enormous numbers, too. To avoid accidentally attracting them, put your suet in a bottom-feeding container. These contraptions require birds to hang upside down to use, something starlings don't like to do.

"Suet is great," says Greig, noting that if you start using it, you may suddenly spot a lot of new bird species in your yard. "Even birds such as bluebirds, orioles, warblers and wrens will nibble on suet now and then!"