I Lichen the Beard

 

Oil on Panel - 4 x 4 inches

     This warbler, a Northern Parula, was spotted during migration at my home on September 5th, 2023. It was a yard-list first, and noticed by its song – the one with distinct pauses in between bouts of a rising buzzy trill as described by the Cornell Lab of Ornithology. Examination of my photographs shows it was a male. 

     In my neck of the woods (northern Minnesota), Parulas nest in Old Man’s Beard, a type of lichen that contains usnic acid, a medicinal component of the plant. Historically, when used as a compress by the Native Americans, Old Man’s Beard prevented infection and gangrene. It is apparently edible and contains high levels of vitamin C. Perhaps these two traits of this plant are valuable to remember if I’m ever stranded in the wild. 

     In the south, Northern Parulas nest in Spanish moss. When I lived in San Antonio for a while, Spanish moss took getting used to. I found it unsightly at first, then grew accustomed to it. That which is different should be studied and given proper thought. Now I know Spanish moss is prized by homeowners, and gives Northern Parulas a place to raise their young. 

     When Hurricane Andrew came ashore in 1992, it negatively affected the numbers of Northern Parulas in the Atchafalaya Basin of Louisiana. Over 80% of the trees were damaged due to high winds, but few fell to the ground and few were lost altogether (<10%). One would assume less Spanish moss from being sheared off of the trees would have been the underlying factor in this bird’s reduction, but that wasn’t found to be the case. 

     In a study done by Torres and Leberg from the University of Southwestern Louisiana, the lack of Spanish moss didn't correspond with fewer Northern Parulas. So, what else could have caused their decline? 

     This bird gets its food by gleaning insects off leaves at the ends of branches, often high in the canopy. Because the canopy was heavily damaged, food in the canopy was reduced as well. Without the canopy, the number of understory plants increased heavily, as is often the case with hurricanes. A defoliated canopy and a denser understory both negatively affected the population of the Parulas; and while Spanish moss is highly sought after for nesting by this bird, it was perhaps more affected by the disappearance of its food source high in the canopy of the forest. 

     Many birds get their food in specific ways, and from specific sources. This bird prefers to eat insects from leaves high up in trees, a defining attribute of the Northern Parula.

My photo of the Northern Parula flying as seen on 9/5/2023.
Orange and black on the breast is indicative of the male sex.

References

Information from the All About Birds website, https://www.allaboutbirds.org/guide/Northern_Parula/sounds © Cornell Lab of Ornithology. Retrieved Oct. 16, 2023.

Information from the Wikipedia website, https://en.wikipedia.org/wiki/Hurricane_Andrew © Wikipedia. Retrieved Oct. 16, 2023.

Information from the Woodland Trust website, https://www.woodlandtrust.org.uk/trees-woods-and-wildlife/fungi-and-lichens/beard-lichens/ © Woodland Trust. Retrieved Oct. 16, 2023.

Stephenson, T. and Whittle, S. (2015) The Warbler Guide. Princeton University Press. 

Torres, A. R., & Leberg, P. L. (1996). Initial Changes in Habitat and Abundance of Cavity-Nesting Birds and the Northern Parula Following Hurricane Andrew. The Condor, 98(3), 483–490. https://doi.org/10.2307/1369562