Endangered Bats and Construction Project Impacts

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I have been in the environmental compliance world for the better part of my working life. Part of the reason I started down this career path was my love for the environment, and I wanted to have a direct part in protecting it. I have worked as an Environmental Inspector on an array of utility construction projects throughout Ohio, West Virginia, and Kentucky, helping contractors stay compliant with environmental regulations and permits related to their projects. Environmental inspection and compliance work entails protecting the integrity of our water resources such as streams and wetlands, ensuring restoration efforts are successful, and protecting endangered species like the Eastern Massasauga Rattlesnake or the Spotted Turtle.

You may not be familiar with this line of work, but I’m sure you could have guessed I was involved with the things I listed based on the job title. However, what most people aren’t aware of is that Environmental Inspectors also help contractors on construction projects comply with regulations put into place to protect bats as well! Yes, bats, the little furry flying rodents.

Why You Should Care About Bats

Even for experienced construction crews, the regulations surrounding the protection of bats are often an unexpected hurdle. Many times when I’ve brought up the regulations to construction personnel during a pre-job meeting, I’ve been met with a few chuckles or laughs and have even received a disbelieving, “All this… just to protect a bat?!” I am passionate about the idea of doing all we can to protect these little critters, and I think the reason there tends to be pushback is just a matter of being misinformed. 

Clearing Up the Misconceptions

In today's society, bats get a bad rap. They are often viewed as disease-carrying flying rodents. While it’s smart to have a healthy awareness of the fact that bats can carry diseases (rabies being the most commonly talked about) and to be safe and take precautions to avoid contact, rabid bats are not as common as you may think. According to the CDC, “The good news is that most bats don’t have rabies.” The Maine Center for Disease Control and Prevention states, “Most bats are healthy and contribute to our environment in many ways, particularly by consuming insect pests. Less than 1 out of every 200 bats randomly sampled is positive for the rabies virus.”  

Another factor contributing to bats being so misunderstood is that they are nocturnal and not very commonly seen, giving them an air of mystery and darkness. They also have a face only a mother could love. Even Halloween has influenced their image, associating them with vampires, haunted houses, graveyards, and the “scariness” of the holiday. Although vampire bats are real (though not native to the U.S.) there is nothing to be afraid of or dislike about our furry flying friends. Perhaps as we dive deeper into understanding more about how valuable bats are in supporting healthy ecosystems, it will explain the efforts that must go into protecting them.

How do bats support healthy ecosystems?

Bats play an important role in many ecosystems worldwide, including pollinating plants, dispersing seeds, and controlling pests. For example, bats are major pollinators of many types of cacti that open their flowers only at night when bats are active. While many bats eat insects, other bats feed on nectar and provide necessary pollination for plants like peaches, bananas, and agaves. Fun fact: bats are the sole pollinator for the agave plant! Fruit-eating bats also distribute seeds to maintain plants and forests. As much as 95% of the seed dispersal that generated early growth in recently cleared rainforests is credited to bats.

Bats play a key role as insectivores throughout most of the regions in which they are found. They prey on a wide variety of insects like mosquitoes, beetles, flies, moths, and gnats to name a few. The benefit of this is that the majority of insects that make up a bat’s diet tend to be species that are considered to be pests that may have negative effects on crops or native vegetation. These insects may also carry disease-causing agents such as West Nile or the Zika virus. These pests tend to make up the majority of a bat’s diet essentially because they are the species that tend to reproduce the fastest and have the largest populations. Bats are seriously effective at eating insects!

According to the U.S. Forest Service, some small bats can catch up to 1,000 or more small insects in a single hour, sometimes catching more than 4,000 insects in a night. Remember, those numbers are from one individual bat! If you start to consider a whole colony of bats over an entire summer, that’s a lot of insects! In the United States corn industry, recent studies have shown that bats eat enough pests to save more than $1 billion per year in crop damage and pesticide costs alone. That’s a pretty significant impact. Unfortunately, as bat populations decline in many areas throughout the U.S., the agricultural benefits that bats bring will also be directly affected.

The Decline of Bat Populations

For those of you who grew up in the 90s or earlier (I may be dating myself a bit here), you may remember playing outside after school as the streetlights came on, seeing bats dart and flutter above your head, catching whatever insects were unlucky enough to be in their way. I remember this very vividly. Seeing bats while playing street football, as the sun was dropping below the horizon, is burned into my memory from childhood as much as the coo of a mourning dove sitting on a powerline. Sitting here writing this as an adult, I can’t remember the last time I saw a bat. Can you? Maybe it’s because we are all too busy to notice things like that anymore, or maybe we don’t get outside enough. That’s probably part of it, but it’s surely not the whole story. Unfortunately, bat populations have been on the decline over the last few decades across much of the U.S., and it’s become a dire situation.  

There are about 45 species of bats known in the U.S. and Canada, and according to The Nature Conservancy, more than half of the bat species in the United States are in severe decline or listed as endangered. During my time as an Environmental Inspector, most of my experience was with one particular species of Federally Endangered bat, the Northern Long-Eared Bat (Myotis septentrionalis). The Northern Long-Eared Bat is native to 37 U.S. States, the District of Columbia, and much of Canada and has seen significant declines in recent decades. Experts believe this is likely due to many factors, including the bat disease known as white-nose syndrome, habitat loss, wind turbine-related mortality, and climate change, which is expected to impact as many as 82% of bat species in North America in the next 15 years.

Migration and Hibernation

What’s interesting about Northern Long-Eared Bats is the fact that certain populations migrate, like birds. During the warmer months, the bats spend time in forests and wooded areas feeding and raising their young in roost trees. These maternal roost trees can hold 30 to 60 bats with one pup each (*an important fact that will come up again later in this article when we discuss how bats affect construction projects). As temperatures drop and insects become scarce in the fall, the Northern Long-Eared Bats migrate to reach their winter hibernation sites where most mating occurs. These hibernation sites (called hibernacula), usually in caves, are crucial for bats to conserve energy during the winter months by keeping warm and dry. Once spring arrives, the bats then return to their summer grounds to raise their young and feed, starting the cycle over again.

What is white-nose syndrome?

These hibernacula - and the prevalence of white-nose syndrome in these caves - are also one of the reasons this bat is so vulnerable to population decline. White-nose syndrome is a disease affecting hibernating bats and is caused by the fungus Pseudogymnoascus destructans (Pd). Pd appears as white fuzz on a bat’s face, hence the name white-nose syndrome. This fungi thrives in cold, dark, and damp places, attacking bats' bare skin during hibernation, making them unusually active and depleting vital fat reserves needed for winter survival. This can cause them to starve leading them to leave the warmth of the cave in search of food, and freeze to death, wiping out an entire hibernacula in a single winter.

White-nose syndrome was first observed near Albany, New York, in 2007, which directly correlates with the Northern Long-Eared Bats’ decline. Since 2006, in the parts of their range where their populations have been hit the hardest, the number of Northern Long-Eared Bats gathered from hibernacula counts has declined by 97 to 100%. During these hibernacula counts, researchers go into the caves during the winter months and literally count the bats on the ceiling. To put this dramatic decline into perspective - for every 100 bats that were once on the ceiling pre-white-nose syndrome, there are now zero to three.

Northern Long-Eared Bat White-Nose Syndrome Zone

How do bats affect construction projects?

Endangered Species Act

Along with several other species, the Northern Long-Eared Bat is federally endangered, and several regulations under the Endangered Species Act (ESA) have been put in place to protect its habitat. How does this affect construction personnel on land development projects? When a construction project requires tree removal, as many utility construction projects usually do, this can become an issue. Projects falling within the bat's range and causing potential impacts to the bat or its habitat will require some serious forethought to meet ESA requirements. This is where the role of an Environmental Inspector can help ensure that the compliance requirements are being met.

A quick overview of the current ESA regulations:

  • In 2015, the Northern Long-Eared Bat was listed as a “threatened” species and regulated under its species-specific rule issued under section 4(d) of the Endangered Species Act (ESA).

  • On November 29, 2022, the U.S. Fish and Wildlife Service (FWS) published a final rule to reclassify the Northern Long-Eared Bat as “endangered” under the Act. This ruling then came into effect on March 31, 2023, and removed its species-specific rule.

  • Section 7 of the ESA mandates permitting agencies to consult with the FWS before permitting actions that could jeopardize bat habitat.

  • Section 9 of the ESA generally prohibits any "take" of an endangered species without an incidental take permit and an approved habitat conservation plan, potentially leading to civil or criminal penalties. Many utility projects fall under this category. This means that if trees are expected to be removed for construction, a lot of consideration and planning must be made beforehand.  

Maternal Roost Trees

Measuring only 3 to 3.7 inches in length, the Northern Long-Eared Bat is about the size of your thumb. That’s it! Its compact size allows it to fit into tiny spaces underneath peeling bark, in tree cavities, and in crevices of both live and dead trees. Remember the maternal roost trees? During the summer months, cutting a tree down that bats and their pups are roosting in could be detrimental to a local population. It is recommended that trees larger than 3 inches in diameter at breast height (dbh) should be removed only between the dates of October 1 and March 31, when bats are hibernating.

The entire state of Ohio falls within the range of the federally endangered Northern Long-Eared Bat, and so the assumption is that the Northern Long-Eared Bat is present wherever suitable habitat exists. If a bat could live in the tree and it is 3 inches in diameter at breast height (dbh) or grater, then cutting down that tree is prohibited from April through September. This can have huge impacts and consequences on construction and meeting deadlines.

Bat Presence/Absence Surveys

Not being able to cut down trees all summer can pose significant issues and delays on a construction project. The obvious solution is to plan ahead and do all the necessary tree-cutting from October 1 - March 31. Yet many times contractors are unaware of the regulations and can be caught off guard when they are ready to cut trees and then realize that it’s prohibited during that time of year.

There is a solution, though, that doesn’t pose any risk to the bats and can be done during the summer months: a presence/absence survey. This entails hiring a bat biologist and conducting a survey to determine whether bats are present or not. Depending on the nature of the work, this can be a pretty complicated process, but it helps to ensure that the regulations are complied with and ultimately protect the bats. This is a situation where an Environmental Inspector would be able to help the contractors determine which trees are roost trees and record and photograph the tree removal to document compliance.

State-Specific Species Regulations

Although I’ve focused this article on the Northern Long-eared Bat, I want to show some love to the Indiana Bat (Myotis sodalis), which was first listed as federally endangered in the late 1960s. The Northern Long-eared Bat and the Indiana Bat are quite similar in the way that they’re treated, and both are protected under the Endangered Species Act. As of September 13, 2022, the U.S. Fish and Wildlife Service has proposed listing the Tricolored Bat (Perimyotis subflavus) under the Endangered Species Act as well. This species covers a more extensive range than any currently listed bat species, and its potential listing may entail significant regulatory considerations.

Both the Indiana Bat and the Tricolored Bat face extinction for all the same reasons as the Northern Long-eared Bat does, notably white-nose syndrome and habitat loss. While the federal list currently has more than 15 species of bats listed, don't forget each state has its own list of threatened and endangered species, and you may find your state has additional requirements due to the state-specific species. Just be sure to always consult federal and state wildlife agencies for guidance before moving forward.

Working with experienced Environmental Inspectors who can help contractors understand and follow all the federal and state regulations on endangered bats not only helps protect the bat population but also helps keep a project on schedule and compliant.

How You Can Help Bats

Wondering how you can help protect bats? Here are some easy ways that you can help protect the bat population:

  • Help eliminate light pollution. Turning off unnecessary outdoor lights can create a more favorable environment for bats, helping them navigate and hunt more effectively.

  • Support natural habitats by preserving trees for potential roosting sites during the summer months, establish insect-friendly gardens, and install bat boxes. Creating a healthy local ecosystem can go a long way.

  • Don't forget to show consideration for hibernating bats by avoiding caves and mines.

  • Be a bat advocate and talk about bats. Bring them up in your conversations. Educate yourself about bats and maybe share this article with others to help dispel myths and promote understanding.

Bats are an integral part of our ecosystems and have been flying around this planet, in some form or another, for the last 50 million years. Unfortunately, this is a pretty critical point in time for them. Hopefully, if we all do our part, then the next generation will also have memories of bats darting and fluttering above their heads while they throw the pigskin around as the streetlights come on.

Author

Josh Grund
Manager of Social Media and Videography
(former Environmental Compliance Specialist)
KERAMIDA Inc.

Contact Josh at jdgrund@keramida.com

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