Photo by Richard @ SearchNet Media
Are your hummingbird feeders being drained at night? Great, you are indeed helping endangered species.
Most of Arizona's 28 bat species eat insects, but the federally endangered Lesser long-nosed bats (Leptonycteris yerbabuenae), and the Arizona species of concern Mexican long-tongued bats (Choeronycteris mexicana), drink nectar from hummingbird feeders, and also eat pollen and fruits from plants such as the saguaro and agave.
The bats migrate north from Mexico and arrive in southern Arizona as the Saguaro cactus and agave begin to bloom, traveling throughout southern Arizona and then they return south in the fall.
Douglas says "I do like helping them out".
In the fall I usually remove my hummer feeders at night especially the ones on the patio as the bats are sloppy eaters and their mess attracts ants and bees. So, I use an Aspects Oriole feeder (larger food ports) that hangs on a bracket outside our wall. In parallel, beyond that wall and in the back woods I hang several Dr. JBs hummer feeders with the food port flower removed so the food port is larger for their slurpy tongues. I also have several hummers feeders that are in a bat proof cages made with green Home Depot fencing. This assures that if I oversleep at least the hummers will have some nourishment at daybreak.
I pretty much have it all in balance, as much as you can with Mother Nature. My neighbor is a biologist with the U.S. Fish and Wildlife Service/ Arizona Ecological Services Field Office and he uses two Dr. JB’s that also get drained by the bats every night.
A nectar promo for us. We have tried side-by-side feeders---one with our nectar and one with just sugar and the bats empty the nectar feeder quicker than the plain table sugar solution. Another night we thought the location of the feeder had some influence so we switched and indeed the nectar feeder was emptied more rapidly. Thus, we surmise the bats, as do hummers, prefer the sweetness of our nectar---as it has sucrose, dextrose and fructose. Fructose is 1.8 x sweeter than just plain white table sugar.
Have fun with your bats
Bats at Hummingbird Feeders and Bat Night
We sometimes hear from customers who ask if hummingbirds can empty a full feeder overnight. We explain to them that hummers are asleep all night, not out foraging. What they are experiencing is nectar-eating bats. There are three species of bats that are known to frequent, and usually empty, nectar feeders in a single night. These bats are somewhat common in selected regions of the southwest, particularly in areas that border Mexico. Two of the species, the Mexican Long-nosed and the Mexican Long-tongued Bats, are frequent visitors to backyard feeding stations in our region of Southeastern Arizona.
One is considered critically endangered and the other is considered seriously threatened. This means that continued habitat fragmentation and habitat loss are major reasons for their declining numbers. Critically endangered means that in the next several years, perhaps in as few as ten, extinction may be what they are facing. There are also several other explanations which may contribute to their perilous demise. But, whatever we can do to help support bat communities, we should do. Nectar eating bats don’t use bat houses but feeding them with nectar feeders makes their lives a little easier. For insectivore bats (bats that consume insects as the staple in their diet) providing housing is a big help in conserving their numbers.
From late July till close to the end of the year, nectar eating bats are present in some regions of the border states. While they may be present in smaller numbers at other times of the year, at the height of their season, they consume each night as much as 90 ounces of nectar from my backyard feeders. We, and many others, are more than happy to accommodate these bats. They are very important to their environment and the desert landscape. As they are the major pollinators and propagators of many of the plants that symbolize the Sonoran Desert, their eventual extinction will have a terrible effect on the total ecology of the region. So, we gladly give them all the nectar they can slurp. We consider it a small sacrifice to make in order to benefit nature and the natural world.
They cannot hover as long or as well as a hummingbird, but they can hover long enough to get their long tongues into the feeder for a quick slurp. The larger the food ports, the easier it is for the bats to access the nectar. Feeders that have very small food ports won’t discourage them, it just makes it harder for them to use efficiently. Smaller food ports usually mean more of a sticky mess. So, to keep the feeders relatively clean, but more so for their ease of use, we prefer and encourage others to use larger capacity feeders that feature larger food ports.
The single best feeder to use in attracting and feeding bats is the Aspects Oriole feeder. This is a 16 ounce capacity pan-type feeder (flat bottomed with the reservoir of nectar below the food ports) less prone to becoming a sticky mess. This feeder design has larger than standard nectar food ports and does not leak, drip or spill nectar. The bats’ large gage tongues easily get coated with nectar. While they will find and use any nectar feeder, we discovered years ago that this is the single best feeder for bats to use. We have tried many others, but the bats are most successful with this particular model.
If you have other nectar feeders you want to convert into bat feeders, this can be easily accomplished with little effort. Pan-type feeders always make it easiest for bats to use without making a huge mess. Pan-type feeders provide complete top access without them having to navigate around a bottle at the top of the feeder and typically have larger than usual food ports. Enlarge the food ports by using a ¼” or 3/8”drill bit to provide the easiest and cleanest access. Be sure to file, scrape, or burnish any remaining sharp material under the food port after using the drill. We don’t want any bats cutting their tongues. We have done this successfully with Aspects’ Excel and Ultra models.
Another good tip to follow if you want as clean (non-sticky) a feeder as possible is to pole or post mount your feeder. Most typical gravity fed, vacuum-based feeders are only designed to hang, whereas most pan-type feeders have a hanger above and a pole mount built into the underside of the feeder. Usually, a ½” pipe or PVC tube or a 5/8” wooden dowel works well to pole mount such feeders. The added advantage of using a pole mounted feeder is that, unlike hanging, which can swing and drip, the pole mounted feeder always stays stable. This not only prevents any spilling possibilities but gives the bats a solidly placed feeder with no movement which makes it easier for them to hover for a nanosecond, giving them the opportunity to get nectar without the usual sloppiness.
Watching bats at hummingbird feeders is fascinating. While flying, bats are hard to observe in detail. However, they tend to forage heavily for a while and then take breaks while they digest what they have ingested. If you have a place where they can roost (always upside down) relatively close to the feeder they are using, you may have the opportunity to observe what few people actually notice – that is their exercising.
This is the most interesting of all bat behavior we have witnessed. They will spend 30-60 minutes after a foraging bout hanging from one foot only, twisting their bodies almost 360 degrees to the right, then repeating the twisting in the opposite direction. It is rather amazing to watch this exercise. I asked one of my favorite bat biologists about this behavior, explaining that I thought it looked an awful lot like actual exercise. She agreed that’s exactly what they are doing. It’s important for them to keep themselves in top physical condition and this exercising is important to accomplishing that task.
Then I noticed their extremely long tongues (equal to their entire body length!) being extruded and they began twist their tongues in many configurations. Left and right, in and out, and into pretzel-like configurations. It was explained to me that they also need to keep their tongues in perfect condition. Their tongues are the perfect tool for their ability to get nectar from deeply recessed flowers and nectar feeders. So, their tongues need to be kept very flexible so they can maneuver into curved areas and bend their tongues to whatever angle angle they need to most easily access the nectar they are after. If you have the ability to observe this very unusual behavior, it is worth the time it takes to see this magnificent show they will put on for you. I suggest you pull up a chair and enjoy your viewing for 20 minutes or more. It’s as good a show as nature puts on, better than watching it on PBS or Animal Planet!
While hummingbirds, orioles, bats, butterflies and bees all share the same natural nectar sources in the wild, it is very important to be sure your hummingbirds are fed real nectar. They have fragile bodies and unique, very high metabolisms. The other pollinators can metabolize sugar water fairly efficiently. Hummers always function at peak levels when they utilize nectar, whether in the wild or at our feeders. So, either high quality nectar or plain sugar water in a 5 or 6 to 1 ratio will prove very appealing to nectar eating bats.
For further information, read our articles on bats or feel free to contact us.