Detect

July 23, 2023

George McCaa, U.S. Bureau of Mines

Toward the back of the front section of today’s newspaper I found a list of the most seen birds in the US.  The top five species were highlighted for their individual uniqueness.   This begins with an immigrant to North America, the House sparrow (Passer domesticus).  The house sparrow originated in the Middle East and spread to most of Eurasia and parts of North Africa along with agriculture.  By the mid-19th century, it had reached most of the world, primarily through deliberate introductions.  The American goldfinch (Spinus tristis) comes in at #2 and is unique among its finch subfamily as the only bird to undergo a complete molt.  The male is a vibrant yellow in the summer and an olive color during the winter, while the female is a dull yellow-brown shade which brightens only slightly during the summer.  The Dark-eyed junco (Junco hyemalis) ranks #3 and is the most variable in color across the US.  These used to be called separate species but have been lumped together over the years.  The Mourning dove (Zenaida macroura) comes in at #4 and is one of the most harvested birds in North America.  Hunters killed 11 million birds in 2020 and another 9 million in 2021.  Still, the doves’ prolific breeding habits have saved them from decline.  Rounding out the list at #5 is the House finch (Haemorhous mexicanus) which is unique as both native and introduced in the US.  The species is native to western North America and Mexico and the birds were being shipped to New York City and sold as “Hollywood finches”.  When authorities cracked down on the trade (Migratory Bird Treaty Act) the pet store owners released the birds into the wild.  They thrived and within 60 years had reconnected with their western counterparts.  You can now detect all five birds in yards across the US.

When I went online, I found the Migratory Bird Treaty Act of 1918 is a US federal law enacted in 1918 for protection of migratory birds between the US and Canada.  The statute makes it unlawful without a waiver to pursue, hunt, take, capture, kill, or sell nearly 1,100 species of birds listed by the act as migratory birds.  The statute does not discriminate between live or dead birds and grants full protection to any bird parts including feathers, eggs, and nests.  A March 2020 update of the list increased the number of species to 1,093.  The US Fish and Wildlife Service issues permits for otherwise prohibited activities under the act.  These include permits for taxidermy, falconry, propagation, scientific and educational use, and depredation.  An example of this was the killing of geese near an airport, where they pose a danger to aircraft.  The law was enacted in an era when many bird species were threatened by the commercial trade in birds and bird feathers and allowed authorities to detect and prosecute the illegal trade.

Geoff LaBaron, director of the Christmas Bird Count for the National Audubon Science, said these common birds not only eat bugs and seeds of invasive species, but also provide enjoyment for backyard birders (like me).  These species serve as a barometer to detect the declining health of an environment.  Since these bird species are all on the decline, Ken Rosenberg of the Cornell Lab of Ornithology called them the “canary in the coal mine”.  “If we can’t keep healthy populations of these birds, that’s what’s really telling us our overall environment is degrading.” 

Thoughts:  The idea of placing a warm-blooded animal in a mine to detect carbon monoxide was first proposed by John Scott Haldane in 1895.  Canaries (Serinus canaria domestica) were use in British coal mines to detect carbon monoxide and other toxic gasses before they could hurt humans.  The canaries did not fare so well.  The practice was phased out in 1986 with the modern carbon dioxide detector.  Researchers estimate 862 million sparrows and 3 billion birds overall have been lost since 1970.  We need to pay attention to the canary.  Act for all.  Change is coming and it starts with you.