SFI BLOG

By Rachel Hamilton and Darren Sleep

When thinking about bats, you might be reminded of the saying “blind as a bat” or remember one of the many movie scenes where a bat is tangled in someone’s hair — or perhaps the fangs associated with blood-sucking vampires. These tropes about bats help give them the universally creepy and spooky allure that makes them centuries-old inspiration for Halloween. But these associations are mostly myths based on half-truths.

In fact, we at SFI would like to clear up a few of these misconceptions and take a moment this Bat Week (annually timed to coincide with the week of Halloween) to share our appreciation for the ways forests and bats work together. Bats are not blind (they actually have rather good vision for nocturnal creatures), but they do rely on echolocation, which is essentially “sound-radar,” to help them locate and capture prey. This unique navigational trait is also why bats don’t get tangled in your hair… no matter how long it is. As for the vampire connection, vampire bats do exist in Central and South America, feeding mostly on sleeping birds and mammals. They don’t turn into human-like creatures that fear the sun and a delicious piece of garlic bread!

What is less known about bats is far more interesting:

• Bats are pollinators, their feces have been used as fertilizer for hundreds of years, and they are significant factors in the control of insect and pest populations.
• Bats are found almost everywhere in the world and are particularly abundant in forests
  Bats can often be detected at night zipping between trees and above the canopies of forests worldwide, especially in North America, where forests sustainably managed to the SFI standards provide significant bat habitat. In the Canadian boreal, it’s not unusual to find colonies of mother bats and their pups living together in aspen trees, sometimes in hundreds at a single location.
• Bats do have a scary issue affecting their health and survival
  Described as “the most precipitous wildlife decline in the past century in North America”, white-nose syndrome (WNS), a fungal infection deadly to bats, was first identified in a cave in New York in 2006 and has now spread across bats in much of eastern North America. The fuzzy white fungus often appears on the face and wings of hibernating bats, causing them to wake more frequently during hibernation, burning up important fat stores needed to survive the winter. WNS has resulted in the death of millions of bats and contributed to the listing of several species as “imperiled” under the U.S. Endangered Species Act and the Canadian Species at Risk Act.

Bats are an important component of forests and how they are managed. At SFI, biodiversity values and ensuring protection for threatened and endangered species — including bats — have become an important focus of what we do.

SFI has also collaborated on research to look at how bats use forests following harvest and regrowth. Working with the National Council for Air and Stream Improvement, Inc., the Forest Products Association of Canada, and the University of Regina, we joined a conservation project examining the use of SFI-certified forest areas harvested 25 years ago to see the effect on bat populations. Researchers found that bats returned to previous levels of activity as the forest’s trees, bugs, and bushes also returned.

SFI also engages in community outreach and youth education to raise awareness about bat conservation. In 2021, SFI’s Community Grants Program funded the Minnesota SFI Implementation Committee’s Forest Bat Habitat Improvement Project, which collaborated with the Boy Scouts of America to build and erect over 100 bat roosting boxes from SFI-certified wood donated by Norbord Inc. (now West Fraser). In the summer, bats can be found roosting in trees, caves, buildings, and under bridges. Bat boxes provide an alternative “housing” option, particularly for mother bats to raise their young in the summer, which promotes bat population health for these declining species in Northern Minnesota, where they are particularly vulnerable to WNS.

PLT has compiled a selection of free Bat Week resources for anyone celebrating with children.

To further introduce and connect youth to the world of bats, SFI is celebrating Bat Week, which annually occurs in the last week of October, from the 21^st to Halloween, the 31^st. Project Learning Tree, an award-winning educational initiative of SFI, compiled a great selection of resources to engage youth in learning about and celebrating bats through activities, arts, and crafts for a variety of ages. Through education, research, and engaging partnerships at various levels, SFI hopes to dispel some misconceptions about bats, raise awareness about challenges they face, and highlight the critical role bats play in helping sustain our forests and contributing to our everyday lives.

Rachel’s Bat Story

Bats have a reputation for being spooky and scary. Through my bat research experiences, while pursing my graduate degree, I found these furry friends to be fascinating. This graduate opportunity led me to study bats in Ontario, Jamaica, and Cuba – exploring caves, mines, forests, and barns. It was not the bats that I feared, but rather other uncomfortable encounters that occurred while in their environments.

One early morning in Ontario, my co-researcher and I were taking turns checking mist nets, soft “volleyball” like nets specialized to safely catch unsuspecting flying animals for migratory bats passing through the area. I was walking solo down the dark path, with just my headlamp illuminating the way when I spotted eyeshine from a somewhat large animal in the distance…was it a deer? Was it a bear? I will never know, and I wasn’t going to stay long enough to find out! I promptly returned to the safety of our field station to get support from my research partner (safety in numbers!) to finish our rounds.

A different evening in Jamaica, exhausted after a long night of catching bats in the forest, the research team finally laid down to get some rest at the research station when my roommate woke up with a scream. She said something just fluttered across her hand. I said maybe she screamed loud enough to scare it away. Then we heard more scuttling noises. Quickly turning on the lights, the biggest rat we ever saw was scampering across the ledge beside my roommate’s bed.

The intensity of heat is due to the body heat of the high density of bats which creates a microclimate. Thus, bats can live in a protected, high-heat chamber that is unsuitable for most other species, especially predators or even visiting researchers who can barely stand the heat. I was thankful to go back to the cool cave with the other creepy-crawly wildlife. So, in my experiences, I didn’t find bats scary, but rather eyeshine in the night, rats in my room, and scorpions crawling on pants made for less-than-ideal situations!

Darren’s Bat Story

As a kid, the only thing that scared me was the dark. I didn’t really fear what might be in the dark – I felt I could handle the critters – it was just not knowing where they were or what they were doing that weirded me out. So naturally, I chose to pursue graduate studies in nocturnal ecology, giving all sorts of critters the chance to sneak up and scare the bejeepers out of me. I’ve been startled and caused to jump out of my skin by bears, moose, elk, wolves, coyotes, skunks, porcupines, most owl species in North America, and many, many bats.

When you are a wildlife biologist, it’s often assumed you can simply solve simple human-wildlife conflict issues quickly and effectively. Helping bats find their way back outside of a human’s home is a popular request friends ask me to help with. I have easily caught bats inside and let them go after a quick natural history lesson. Others have evaded me for hours, making me look like a stumbling fool and discrediting me in front of friends and family.

It’s been said that doing research is “…what I’m doing when I don’t know what I’m doing,” and that’s certainly been my experience with wildlife. Bats are particularly reliable for being anything but reliable as research subjects. When I was first trained to mist net bats, we caught 20-30 bats in one evening outside of a well-known little brown bat maternity colony. Little browns are cute and harmless critters, about as non-threatening as their name sounds. Weighing in at less than half an ounce, even angry a little brown bat could not bight through the skin on your finger on a good day. Ready to take on the bat world, the next night, I was mist netting over a nearby river. After handling a couple of little browns, a bat hit the net so hard I was sure I had caught a crow. Instead, I was faced with a fistful of a spitting and hissing bat, nearly 5-6 times the size of a little brown. Hoary bats have formidable teeth, and this one was quick to express his displeasure at being caught while out looking for his dinner. After extracting him from the net, he calmed down nicely. We processed and weighed him, and he was on his way. He might have calmed down, but it took me quite a while to do the same.

In the forest, several bat species roost in holes and crevices in trees, particularly in aspen trees that develop heart rot as they age. Identifying which crevices are used and why can be a challenge. Researchers usually try to catch females at night using mist nets and affix radio-telemetry tags to them, following them the next day to find communal roosts where 3 to 5 females might be hanging out for the day. Radio-tagging is tricky business, and the bat is very carefully handled to gently affix the tag so it won’t hurt her, inhibit her flight, and she won’t lose it. Bats naturally switch between roosts daily, so if researchers can capture and tag some of her friends, it can help find other roosts and better understand what makes a “good” day roost.

A colleague of mine in grad school came up with a brilliant way to efficiently capture the other female bats in a roost. Bats don’t generally take off from a sitting position as they are not usually on a flat surface like the ground. (Note: a bat on the ground is NOT acting naturally; call a professional to handle a bat on the ground). Bats normally fall from a height before opening their wings to fly, as from the roof of a cavern, a wall, or the opening of a tree crevice. My colleague took a box from a 24-case of beer (I never found out what he did with the previous contents) and stapled it to the tree just below the crevice in the tree. He then opened the bottom of the box and stapled a garbage bag to the bottom. It looked like a giant black sock hanging from the side of a tree. He then sat under the tree and waited for dusk.

Bats tend to emerge just as the sun sets, making the most of the pulse of insects at that time of night. It was no surprise to hear the “plop” in the bottom of the bag above his head at the witching hour. As he was about to celebrate the joy of an idea well-conceived, his joy turned to terror as the “plops” increased in both total and frequency. All told, there were more than 30 females in that one roost. He had neither the time nor the tags to process all the bats he caught that one night in his 24-trap, and he ended up releasing some and working all night to process the ones he kept.

I have never regretted working late at night in the dark. Now I’m very comfortable in the darkness, and I love the possibility of seeing bats against the night sky, hearing distant owl or wolf calls, and knowing the forests I love continue to hold their secrets I can explore – even if sometimes I might get a fright!

Rachel Hamilton is SFI Manager of Conservation Programs, supporting the SFI Conservation Program by aiding in conservation grants program tracking and contributing to conservation communications, research, and collaborative projects.

Darren Sleep is SFI Lead Scientist, responsible for the incorporation of up-to-date and scientifically rigorous technical content across all SFI’s pillars, ensuring that SFI’s work is grounded in thoughtful, science-based knowledge and communications, and that SFI standards and education programs reflect the latest in scientific understanding.

Rachel and Darren are members of the SFI Conservation Team, working across the SFI footprint to help address sustainability challenges and inform global conservation efforts. To learn more about SFI’s conservation work, please visit forests.org/conservation.