Mistle Thrush

Mega-Rare Bird Found in New Brunswick

Mistle Thrush [Isabelle Levesque Photo]

Saturday, December 9, 2017 was a watershed day for New Brunswick birders.  On that day our rarest bird ever was found in the yard of Peter and Deana Gadd of Miramichi City.  It was the confluence of several unusual factors that made this event possible.  Peter Gadd is a naturalist/bird watcher and a photographer.  The Gadd yard is large and filled with a huge, fruit-laden mountain ash which is a preferred winter food of thrushes.  There is cover nearby in several large white pine trees.  The province has an active naturalist network allowing fast, excellent communication among birders and experts.  Peter and Deana are presently participating in a Feeder Watch Program so were watching their yard carefully that day to count the birds coming to their property for an online North American database.  The weather had turned to winter conditions forcing birds to come to feeders and fruit trees.  These factors precipitated the sighting of an unusual thrush which was recognized as unusual, photographed, and sent to local authorities who confirmed it as either a Song Thrush or a Mistle Thrush.  Further emails and exchange of photos followed with further sightings, confirmed the visitor as a Mistle Thrush (Turdus viscivorus).  A short time later the news became available to all New Brunswick birders.  It quickly spread to Nova Scotia, Prince Edward Island, Quebec and Newfoundland.  Within a short time the top birders all over Canada and  the United States were informed of the presence of this special bird.  

And special it is indeed!  This is the first confirmed sighting of the Mistle Thrush in North America!  Apparently the Song Thrush has been found once before in Quebec but the Mistle Thrush has not been documented every before in New Brunswick, in Canada or anywhere in North America!  That makes it a mega-rarity.

Mistle Thrush [Hank Scarth Photo]

The Mistle Thrush is a bit bigger than our American Robin.  It is shaped and acts like our robin but is bit more wary.  It is 27 cm long (our robin is 25 cm).  The most conspicuous marking is the heavily spotted breast and belly.  The spots are dark brown or black, large, roundish and on a beige or white background.  Some spots are arrowhead shaped.  The back is a gray brown.  The tail appears longish, is brownish gray with white fringes.  The feet and legs are pinkish yellow.  The throat is light in colour, has dark malar lines and the spots appear to coalesce around the edges of the throat.  The bill is dark gray with yellow showing at the base.  The lores are white and they extend to a narrow orbital ring.  The wings have pale gray fringes.  The wing linings are white or light gray, a field mark which distinguishes this species from the Song Thrush which has rusty-buff wing linings. 

Mistle Thrush [Peter Gadd Photo]

The Mistle Thrush flies in an undulating fashion and folds its wings during the gliding phase much like a pigeon.  This undoubtedly gave it its Norwegian name, 'duetrost', which means pigeon thrush.  The Mistle Thrush apparently sings when other thrushes are silent and often sings in bad weather.  Unfortunately we did not hear this bird vocalize.  

Mistle Thrush [Peter Gadd Photo]

The Mistle Thrush breeds throughout Europe.  It is a permanent resident of the United Kingdom, France, Germany, Belgium, northern Italy and northern Greece.  It winters in southern Spain, southern Italy, the Middle East, and northern Africa.  Its normal range does not include Iceland or Greenland.  

Mistle Thrush [Peter Gadd Photo]

So why or how did this bird come here?  That is the big question.  We have had a phenomenal fall for vagrants coming to New Brunswick.  That is undoubtedly related to the severe wind storms and hurricanes that took place in the fall over North America and the Atlantic Ocean.  Severe winds obviously blew this little bird well off course.  The bird itself could also have its internal navigation system fouled up by disease, pollutants or other unknown factors.  

Mega-rarities draw birders from afar.  To date we have had birders from Maine, Quebec, and as far afield as Wisconsin.  Many, many more will follow if the bird stays around.  Good luck Mistle Thrush and to the birders who come to see it.  

Addendum: The Mistle Thrush appears to have left as of April 8.  The last confirmed sighting was on March 24 when it was seen by visitors from Maine and Arizona.  In total 540 visitors were recorded by Peter and Deana Gadd who were the stewards of this rare visitor.  There were certainly a few more who did not get recorded and many came repeatedly.  Visitors came from 8 Canadian provinces and 28 US states including Texas, California, Oregon, Arizona and Florida.  Canadians came from as far away as British Columbia and Alberta.  Most people who came to see the bird were successful.  The bird was coping well with our winter and did not seem to be affected by its many visitors.