A recent article in the prestigious Journal of Mammalogy discusses the discovery that all species of flying squirrels in North and Central America namely, Humboldt’s flying squirrel, (Glaucomys oregonensis), northern flying squirrel (Glaucomys sabrinus), and southern flying squirrel (Glaucomys volans) all emit a pink coloration when exposed to ultraviolet light. Interestingly, the flying squirrels are not the only mammal that have materials that fluoresce under UV light. In fact the opossum (Didelphis virginiana) also have skin and fur that fluoresce under UV light.
After a researcher saw a southern flying squirrel fluoresce when illuminated with a UV light, researchers looked at museum specimens and a few live animals to see if they too fluoresced. They did. The researchers used the LED UV flashlight (ilumens8 100 LED) which used a 395nm wave length. The squirrels fluoresced on both the stomach (ventral) and back (dorsal) sides.
Researchers are uncertain as to what purpose this coloration plays on behalf of flying squirrels. But they suggested 4 hypotheses which are not mutually exclusive. Those hypotheses are 1) the trait
is adaptive in the squirrels’ unique nocturnal–crepuscular light
environment; 2) fluorescence is especially important on landscapes
with snow cover; 3) fluorescence is used in intraspecific
communication; and 4) fluorescence plays a role in antipredator
I suspect that the characteristic helps squirrels see each other and thereby avoid collisions. But who knows. If the characteristic involves inter-personal communication, can WCOs use it to help capture or repel flying squirrels? Time will tell.
If you are interested in learning more read the article, A.M. Kohler et al., “Ultraviolet fluorescence discovered in New World flying squirrels (Glaucomys),” Journal of Mammology, doi:10.1093/jmammal/gyy177, 2019.Stephen M. Vantassel, CWCP, ACE, is the owner of Wildlife Control Consultant, LLC. He helps people restore their balance with nature through publishing, training, consulting, and the internet. He has published numerous articles in trade and academic publications along with several books (http://kingsdivinity.academia.edu/StephenMVantassel). He is a sought after speaker and trainer. Copyright All postings are the property of Stephen M. Vantassel and Wildlife Control Consultant, LLC. Text (not images) may be reprinted in non-profit publications provided that the author and website URL is included. If images wish to be used, explicit and written permission must be obtained from Wildlife Control Consultant, LLC.