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This page last updated: October 19, 2005 Honey as a Hummingbird Food A More Complete Version Than You've Read Before! Do me a favor. Do a GOOGLE search for [hummingbird nectar honey] and peruse some of the results. At the time of this writing there were 37,400 "hits" with that search, and I would venture to guess that every one warns people not to use honey in their hummingbird feeders. Well, I'm not going to shock you. I'll say the same thing. Don't Use Honey in Your Feeders! The difference is, "Why?" The more reputable websites of those 37,000+ will tell you it's because honey ferments rapidly, and we don't want to serve fermented nectar to our birds. I'll agree with that one. Generally the lower level websites (for lack of a better term) will tell you it's because honey will cause a black fungus on the tongue of a hummingbird, which will kill it. True? That's the purpose of this webpage. I agree that honey is likely not a good substitute for a variety of reasons:
Let's look at those one at a time. The first one is pretty self-explanatory. Most hummingbird researchers think it's pretty important to serve hummingbirds what they actually get in nature, just to be safe. The diet at flowers consists largely of sucrose and water at around 12-34% sugar in California (Baker 1975), with trace amino acids and other minerals thrown in. Honey, clearly, isn't on their wild buffet table! How about #2 -- As you may have heard, honey in it's native state has interesting anti-microbial properties, but dilute it with water and you actually have a great culture medium for growing "bugs." Furthermore, Louisiana hummingbird researcher Nancy Newfield did a quick experiment one winter. She made identical concentrations of honey nectar and table sugar nectar and placed the liquids in separate jars and set them on her windowsill. In less than one day the honey nectar was already getting cloudy, while the table sugar nectar remained clear for several days. Since many people use "cloudiness" to guage when their nectar is going bad, using honey isn't a good idea! OK -- #3. Any pediatrician will tell you that giving honey to infants is a real NO-NO because of the high risk of contracting botulism. Honey, of course, often contains botulinum spores. Adults can deal with these spores, but the immune system of our youngest humans can't. Care must be taken if you extrapolate what happens in humans to what would happen in hummingbirds (we don't know how botulinum spores can effect hummingbirds), but it's perhaps best to be safe and not use honey. #4 -- Hummingbirds are used to consuming primarily sucrose -- a dissachride sugar that is transferred quickly across the gut via osmosis. The primary sugar in honey is actually fructose, a simple sugar transparted across cell membranes via the slower "active transport" mechanism requiring glucose. This works great in limiting the effects of hypoglecemia in humans (it takes longer to get a sugar "rush" eating honey than it does eating a candy bar), but honey also doesn't provide the "quick boost" of energy that hummingbirds are accustomed to (and perhaps require) given their preference for sucrose-containing flowers. While it's true that hummingbirds will feed on fructose sources, they do so infrequently compared to sucrose sources. OK -- what about the tongue-fungus claim? Brazilian naturalist Dr. Augusto Ruschi is credited with determining that a fermented honey-solution can cause a deadly fungus on the tongue of hummingbirds, but I've been unable to date to find the actual citation for this research. If anyone can provide me with Ruschi's peer-reviewed literature (likely in Portuguese) on this topic, I'll [jokingly] name my next child after you. John K. Terres is widely recognized as propogating Ruschi's claim through his dated book "Songbirds in Your Garden" (1953; Thomas Y. Crowell Company, New York). So apparently the research was done prior to 1953. Was this "good" research? Terres apparently considered it worthy of including in his 50 year old book, but the jury is still out. Dr. Ruschi (1915-1986) was elected to the American Ornithologists Union as both an Associate and a Corresponding Fellow in the 1960 (Conway 1991). He published nearly 400 scientific papers in a variety of scientific disciplines ranging from botany and ornithology to anthropalogy. He kept a hummingbird aviary and was considered by many in South America to be the world's leading authority on hummingbirds. Despite that, actual evidence of his research on hummingbird tongue-fungus has eluded us. We're still searching... All that aside, I would still absolutely not recommend honey for use in backyard hummingbird feeders when a proven safe alternative that mimics natural flower nectar (granulated table sugar = sucrose) is available! Finally, I encourage you to be careful about spouting the honey & tongue fungus connection without acknowledging that peer-reviewed evidence to back it up appears to be lacking. (Again, if it exists, I've been unable to locate it). Citations Baker, H.G. 1975. Sugar concentrations in nectars from hummingbird flowers. Biotropica 7:37–41. Buchs, A.E., S. Sasson, H.G. Joost, and E. Cerasi. 1998. Characterization of GLUT5 domains responsible for fructose transport. Endocrinology 139:827-31. Conway, A.E. 1991. In Memorium: Augusto Ruschi, 1915-1986. Auk 108:708.
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