Photo by Larry Kirtley
Happy Hallowe’en! Ever wondered why the loggerhead shrike wears a “mask”? It’s not to go out trick-or-treating!
Some birds– like many species of shrike– have evolved a dark feather “mask”, or eye-stripe, which scientists believe help reduce the sun’s glare when the bird is hunting or foraging. Football players wear “eye-black” to reduce sunlight and stadium light glare in the same way.
Researchers in Israel¹ were able to test this theory with masked shrikes by whitening the black feathers surrounding the birds’ eyes. The birds faced away from the sun when hunting, and were not as successful in catching their prey. The researchers hypothesized that the hunting shrikes cast shadows when they were facing away from the sun, and thus alerted the prey targets to their presence.
Despite these interesting findings, year-round mask-wearing birds are still a subject of ongoing research.
Other species of bird sport eye masks, but for a slightly different reason. The males of certain species will wear bold colours at certain times of the year to attract females.
One thing’s for sure– the loggerhead shrike is well-dressed for Hallowe’en!
Can you name the species of masked birds in this blog post?
All photos courtesy of allaboutbirds.org
¹Reuven Yosef, Piotr Zduniak, Piotr Tryjanowski. 2012. Unmasking Zorro: functional importance of the facial mask in the Masked Shrike (Lanius nubicus). Behavioral Ecology 23 (3): 615–618.
Conservation Breeding Coordinator – Eastern Loggerhead Shrike Program
Jane holds a Master’s degree in Animal Biosciences from the University of Guelph, where she studied building collision injuries in migratory songbird species. Jane worked as a rehabilitation supervisor, where she was responsible for the care, treatment, and reintroduction of injured and orphaned wildlife, including many species at risk.