The month of May in Ontario is like Christmas for birders and bird enthusiasts: millions of migratory birds are returning to their breeding grounds, singing their hearts out for territory and dressed to the nines in flashy colourful breeding plumage. Backyard feeders are suddenly full of bright colours: indigo buntings, orange Baltimore orioles, goldfinches molting into their bright yellow plumage…and city parks are alive with the ethereal melodies of Hermit thrushes and warblers.
Many of these migrating birds, including eastern loggerhead shrikes, have the difficult task of passing through densely populated urban areas of Southern Ontario in the spring before reaching their breeding grounds further north.

A loggerhead shrike taking flight in Carden, Ontario. Eastern loggerhead shrikes (Lanius ludovicianus migrans) are the only subspecies of loggerhead shrike that is migratory. Photo by A. Samuelson.

Unfortunately for migratory birds that travel at night, these urban spaces present a very grave danger.
Nocturnal migrants rely on cues like stars and moonlight to navigate, so a bright glittery city centre is both alluring and confusing. Birds are drawn in and become trapped or are unwilling to leave, and many eventually die from exhaustion or from colliding with buildings.

Nocturnal migrants use visual cues such as starlight, moonlight, and the sun’s position at sunset to navigate back to their breeding grounds in the spring. Picture: WikiMedia Commons

World Migratory Bird Day (WMBD) is an annual campaign to raise awareness for the conservation of migratory birds and their habitats. This year’s theme is Light Pollution: Dim the Lights for Birds at Night!, and the hope is to call attention to the extreme threat city light pollution poses to nocturnal migrants.

Juvenile loggerhead shrike taking flight. Photo by P. Rathner.

Eastern loggerhead shrikes are known to migrate at night, so this year’s theme is especially close to the hearts of biologists at WPC. Thankfully, more and more cities in the world are taking measures to dim building lights during spring and fall migration. Get involved by writing to your local member of parliament or to a local newspaper to encourage municipalities to find creative solutions to reduce urban light pollution, or spread the word on social media about this year’s WMBD theme!

Jane Spero

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.

Jane Spero