Monday, April 9, 2007

Is feeding jelly really okay for birds?


Back in spring 2004, we had an extreme cold spell in May, right at the peak of warbler, tanager, and oriole migration. Suddenly people were finding dead insectivores on walks through the woods, and my yard was simply hopping with birds, including a wayward Bobolink, 7+ Baltimore Orioles, 5+ Scarlet Tanagers, and 30+ Cape May Warblers all visible at any one time. I went through a huge number of mealworms, and vast quantities of suet, sunflower seed, white millet, and jelly. I've been feeding grape jelly for many years. When my 23-year-old daughter was a preschooler, she'd come home from Montessori school wanting a "pickanic" lunch. I'd fix a sandwich and set her up at the "pickanic" table. On the same table was the orange bowl pictured above (we've had these orange bowls for decades--they came free in dog food), with a plop of grape jelly. And every day while Katie sat there, in flew a catbird to feed at the table right alongside her. When I went out, the catbird wouldn't come anywhere near, but for some reason it approved of my tiny daughter. That orange bowl of jelly was EXTREMELY popular in 2004, when birds were cold and food-stressed!

Anyway, I've long fed jelly to birds. I plop it out in very small amounts usually, because it gets buggy fast and I'm sure bacteria thrives in it, so I don't like having out more than birds can eat in a day. But that spring with all those birds, one morning I filled that bowl half full with jelly because I was going to be gone for several hours and the temperature was in the teens. When I came home, I found a Red-breasted Nuthatch close to death, mired in the jelly so that the only parts sticking out were his beak and eyes. I fished him out and spent hours washing him in warm water, toweling him dry, and allowing him to preen, over and over, until he was releasable. I felt horrible about that, and ever since have been cautioning people about setting out only small amounts of jelly at a time.

But today I got a thoughtful email from Kay Charter, who writes:
I confess that I had a prejudice against this practice [feeding jelly] the first time I saw it...about twenty years ago in a relative's yard. It just didn't look right. So I did some digging...as much as it is possible to do, which isn't much and it certainly hasn't been quantified, but it all makes sense. One source was a good friend who is an internist...he said that high sugar foods may trigger a bird's satiety gland, much as it does in children, causing it to feel satisfied when it has had little in the way of nutritional value. He also said that sugar may be addictive for birds as it certainly can be in humans, and that a bird might develop a strong liking for jelly and spend less time searching for natural foods.

Then I queried my friend, Kent Mahaffey, who was manager of the San Diego Wild Animal Park's famous free-flight Bird Show for more than two decades. Kent had primary care responsibility for hundreds of birds from many families. He said he would never allow any birds under his care to have jelly. He added the following:

  • In general, any food that exceeds the balance of sucrose in a bird's natural diet is suspect. Natural nectars contain 12% to 30% sugars, while jams and jellies are more than half sugar. He also said that higher than normal sugar loads may outstrip a bird's ability to adequately process the sugar (as it does in humans); and products high in sugars are an ideal environment for bacterial growth.

He summarized as follows: "Birds developed the way they did by adapting to the environments in which they lived and the foods that sustained them. We do our best for them when we stick as closely as possible to their natural diets."

I know that people have been doing this for decades with no apparent ill effects. But since there is no way to check the effect on internal organs, or, as Kent suggested, bactarial growth, it just seems wise to me to stick with Kent's suggestion...which is to offer foods that are as close as possible to what they evolved with.

SBTH recommends an alternative: grapes. Birds love them, and they have real nutrients, not just sugar.

The bottom line is that while we don't know how this affects our birds, it may (as Kent and my doc friend suggested) be harmful. Why take the chance?

Thanks,

Kay
So what's the right answer? I think it's CRITICAL to stop feeding jelly if there is any evidence birds are feeding it to nestlings or bringing fledglings to it--growing babies need protein, not such a heavy carb load. And if an individual birds seems to be spending an inordinate amount of time at the jelly, I'd close down shop, too. At this point, I'm going to probably continue to feed it during migration, especially during cold weather.

Does anyone know of any studies about the relative benefits and harms of feeding jelly to birds? Let me know!

6 comments:

  1. I'm not sure I'm ready to jump on the anti-jelly bandwagon yet. Birds do have a way of regulating their diet. Orioles do stop eating jelly and that ends right about the time oriole chicks hatch--I think they know enough to switch to protein heavy foods.

    Also, when people tend to go through jelly the most is during migration, you aren't getting the same oriole coming all day long, you're getting several coming through out the day, they aren't eating only jelly.

    Of course, this is only based on anecdotal evidence so it's not scientific.

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  2. I feed Orioles with grape jelly and what a pleasure to watch them. However, after reading the comments, I started to add crushed grapes mixed with the jelly. I will add more grapes day after day, until they get used to it. They already love it. I will look for natural grape jelly or jam, even organic, no sugar, no preservatives added. Now, if it is harmful to feed Orioles with jelly, what about feeding Hummingbirds with liquid nectar. I make my own, without adding any dye. When you find feeders, tips and recipes for Orioles and Hummingbirds on websites like Cornell Lab, Audubon or Wild Birds Unlimited, you go with it without a doubt.
    Lucie, WNY

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  3. Hummingbirds naturally need sugar, They need the sugar for energy. Do other birds need sugar? Hummingbirds also eat insects for protein. I am going to buy a jar of grape jelly today and put out a little bit everyday. It sounds like no one knows for sure if it is ok or not. I will use caution.

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  4. I put out some grape jelly and the orioles found it but so did the honeybees.Does anyone know if this may not only hurt the orioles but the bees too. I don't want to harm anything so after dark I hosed all the jelly away. Any suggestions. I do have hummingbird feeders and regular oriole feeders.

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  5. Thanks so much for the comments. I attracted the orioles to the yard with grape jelly, but seems all the birds are dipping their beaks in it now....and was looking for the answers I found here. I will start crushing some grapes and adding some protein (hummers not incuded here). The sugar addiction connection makes lots of sense. Thanks, will remember oranges too

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  6. My girlfriend found a dead hummingbird in her jelly yesterday. Died the same way you described your nuthatch. Very, very sad.

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