A sharp-shinned hawk keeps an eye out for prey in northern Dickinson County. Predators are a greater nemesis to sweet-toothed orioles than any rumored harm from grape jelly, a regional bird expect says. (Betsy Bloom/Daily News photo)

A reader called with a column suggestion after hearing a worrisome rumor that the grape jelly she puts out for orioles and other birds might be harmful to them.

I had not heard that myself, but I agree a column on feeding these spring arrivals makes sense, given orioles and rose-breasted grosbeaks both turned up this past week in the area.

Since I do not claim any special insight on this, I turned to someone who should know: Laura Erickson of Duluth, Minn., an author who was science editor at the Cornell Lab of Ornithology, one of my favorite online reference sites for bird information. Erickson also has a podcast, blog and long-running public radio program, “For the Birds”; more information on her impressive background can be found on her website, www.lauraerickson.com.

She was gracious enough to give me an interview, on short notice, with advice on feeding orioles and hummingbirds.

Grape jelly should pose no health hazard to orioles, Erickson said, though she admitted she knows of no study done, as that would require, well, doing autopsies on dead orioles or, worse, killing them to examine their internal organs.

But since orioles tend to return to the same area each spring, they can be banded and identified to determine how long they survive. Cornell’s All About Birds website, www.allaboutbirds.org, indicates the oldest-known Baltimore oriole — the most common type in the Upper Peninsula — lived more than 12 years and met its demise not from overindulging in jelly but by being picked off by a bird of prey.

“It’s pretty clear it doesn’t have too much effect, ’cause they keep coming back,” Erickson said.

She did offer one caution about grape jelly — don’t go overboard on the amount and use small containers. One year, at the height of spring migration when she knew she was going to be gone much of the day, Erickson put out a larger bowl of jelly. When she returned, she found a tiny red-breasted nuthatch mired up to its eyeballs in the sticky mass. Luckily, it was a bird she’d been able to hand-feed through the winter, so it was tame enough to endure several baths and survived, Erickson said, though for some time it retained a purple stain on its belly.

Other birds that have a “sweet beak,” Erickson said, include scarlet tanagers and Cape May and prothonotary warblers. The latter, a glowing golden bird with gray wings and tail, can be seen downstate in Wisconsin and Michigan but not here. The Cape May warbler, though, does breeding in the U.P. and northern Wisconsin and is well worth watching for at the jelly dish, with a yellow face and chest and chestnut around the eyes.

Other tips for feeding birds with a taste for jelly:

— Check the label on the grape jelly and avoid any that have artificial sweeteners or coloring. Erickson recommends the jelly be made with sugar rather than high-fructose corn syrup as well. Generally, the simpler the ingredients — like what you’d make at home — the better the jelly likely is to be for the birds, she said.

— Jelly is great for the orioles when returning from migration and, during nesting season, as a morning energy boost before the adults head out to hunt insects for the hatchlings. But if later in the summer the adults keep bringing fledglings to the jelly, well, that’s just bad parenting, Erickson said. “I would shut it down,” she said.

— Remember jelly is sticky, so clean the feeder and containers frequently to avoid having the birds get too messy.

— Oranges are a more natural food, so keep those available as well. Empty peels can be filled with grape jelly, too.

— Other fruits can be placed out but be aware they will spoil more quickly as the weather turns warmer, and could ferment or get moldy, neither of which is good for the birds.

Erickson had similar advice regarding hummingbird feeders:

— Don’t use hummingbird nectar that is dyed red. It’s unnecessary to attract the birds and can harm them, as it can take days for the dye to clear their system. If opting for store-bought nectar, pick one that is clear.

— It’s better — and less expensive — to make nectar at home. Erickson recommends a mix of 4 parts water to 1 part sugar. Use white table sugar, not raw sugar or brown sugar, as they can have minerals that can affect the birds. Some people insist cane sugar is best, but Erickson doubts it makes a difference; buy beet sugar if it’s cheaper. Honey might seem like a natural choice, being derived from nectar, but it gets contaminated too quickly, she said. If the weather turns significantly cooler, a 3-to-1 mix might be used to provide more carbs, but the nectar should be no sweeter than that.

— While some nectar recipes call for bringing the mixture to a boil, presumably to make it more sterile, Erickson said that’s not needed. “The moment a hummingbird’s tongue touches the water, it’s injecting germs into it.” The better route is make small batches and change what’s in the feeder frequently; nectar, especially on warm and sunny days, can go bad quickly. In cooler climates, it might hold up for several days; in the heat, consider swapping it out daily. One definite warning sign: if the nectar goes cloudy, toss it and clean the feeder.

— Rather than one feeder with multiple ports, Erickson recommends several smaller feeders for hummingbirds. Highly territorial and pugnacious, hummingbirds will lay claim to a feeder and chase off rivals, so having feeding sites placed far enough apart they can’t see each other can draw in more hummingbirds without the conflict, Erickson said.

Betsy Bloom can be reached at 906-774-2772, ext. 40, or bbloom@ironmountaindailynews.com.