The Palm Trees Austin’s Bats Depend On

Palm trees are vital habitat for Austin’s yellow bat population and can host up to four other local bat species. To our knowledge, yellow bats roost nowhere else but the brown skirt of palm trees, which hangs below the green crown of live fronds. We’re talking about palms where the bottom of the skirt is at least 12 feet above the ground, allowing bats to drop into flight above the reach of leaping predators.

Winter Storm Uri (The Feb 2021 Freeze Event) had a devastating effect on Austin’s palm trees, with over 90% being killed. This makes the skirts on the surviving palms critical to the survival of the two species of yellow bats. We can minimize the harm to our local bats with careful analysis and best management practices, if palm tree work cannot be avoided and just has to be done.

The brown skirt under the green crown is home to yellow bats in Austin.

Two species of yellow bats roost in the skirts of Austin’s palm trees – northern yellow bats and southern yellow bats. Watching them fly out at night from your palm tree is a natural wonder. Set up the lawn chairs, crank up the margarita machine and invite the neighbors. Add a bat detector and you have a back-stage pass to the best of Austin’s wild nightlife! If you don’t have a palm tree, our Instagram account @austinbatrefuge has tons of great videos where you can get to know them. Give us a follow!

If you own a palm and want some cover as to why you aren’t pruning the skirt, then purchase one of our yard signs and proudly proclaim you support for Austin’s yellow bats!

Two Species, One Roost

southern yellow bat

southern yellow bat pup

northern yellow bat pup

northern yellow bat juvenile

This skirt is valuable habitat for a variety of other wildlife too, including over 20 species of birds. They all love this habitat because they can roost out of the sight of predators, which means they won’t be easily seen by humans either.

Please be aware that yellow bats give birth in these skirts and will be nursing non-flying pups from mid-May through August. Tree work that involves the skirt of the palm tree will injure or kill bats, and orphan the non-flying pups if their mother is scared away by her roost being demolished. Bats feel safe in palm fronds and generally will not flush at signs of danger. “Birds Bolt – Bats Don’t”. They are deep sleepers (even on warm summer days) and, on top of that, will be in torpor during the winter, even during warm spells, due to short days and low light levels.

We have seen this many times in the last decade. People are unaware there are bats in their yard until a palm tree is removed “lumberjack style” and they find bats with compound fractures of the wing amongst the pieces of fallen palm tree. Or a palm skirt is pruned during maternity season and non-flying yellow bat orphans are found helpless on the ground. Please don’t let this happen to you or your bats.

Native vs. Introduced Palms

Palm trees don’t need to be “manicured” and are best left alone for their longevity and health. Native palms such as our Sabal mexicana and introduced palms such as Sabal palmetto stand up very well to wind events and giving them a “Hurricane Cut” (removing the skirt of old fronds also acts to insulate the trunk of a palm against freeze events such as that caused by the Feb 2021 Polar Vortex) does not make them any more resistant to storms.

For a great primer on local Austin palm trees, see Identification of Palm Trees in the Austin, Texas Area: A Casual Guide for Distinguishing our Native Sabal mexicana from the Aliens by late, great and witty, Landon Lockett.

We’re seeing lots of unfortunate pruning around town.

Palms can be selectively pruned to remove the freeze damage while maintaining the skirt that has been forming over years and that provides critical habitat for as many as six of our local bat species. The new freeze damage has an unruly appearance, like windblown or frizzy hair and we contend that those fronds can be removed (if absolutely necessary) while leaving the skirt (and its valuable habitat) intact. PLEASE LEAVE THE SKIRT!

Please leave the skirt if work just has to be done.

If palms are far enough away from buildings or foot traffic, they would not seem to pose a liability issue for property owners, but of course it is up to the property owner to determine this. We only ask that wildlife be considered and that if at all possible, habitat be preserved.

Best Management Practices

If palms are dead and need to be removed, or pruning must happen, follow these steps to minimize harm to roosting bats.

Make sure your arborist will be using a lift. A lift such as the JLG T350 pictured above can be rented for $216 for four hours and is easily maneuvered into most locations. It is only 4 feet 9 inches wide but allows cutting at 40 feet in height.

Where Bats Hide in Palm Fronds

Bats hide in palm fronds for protection against predators. At a minimum, they will be between two fronds, but often they wiggle up into areas not noticeable at first glance. These areas include the shoulders of palm fronds, double pleats, and cones. See the following video for an example of a bat in a cone formation of a sabal palm frond.

Southern yellow bat hiding in a cone formation of a sabal palm frond.

Above is an example of a palm frond shoulder, another favorite hiding place for bats.

Above is an example of a double pleat, in which bats love to hide. Tri-colored bats are especially fond of these crevices.

Even in Plain Sight

Even in plain sight, they can be hard to spot. Can you find the bat?

This family found the yellow bat below, blown out of a palm by a blue-norther. Dogs often sniff out fallen bats, so keep them on a short leash!

Northern yellow bat blown out of palm tree on a cold winter day. She’s still in torpor (and maybe stunned) after hitting the ground.

Dianne, co-founder of Austin Bat Refuge, releasing that same wild girl back home.

You Can Help

With 90% of Austin’s palms gone, every surviving tree is critical. Here’s what you can do.