(Posted by Andrew D. Smith <[log in to unmask]> via moumn.org)

Please know before reading further that this message is intended to be 
educational, and is specifically NOT intended to be critical or pejorative of any 
observer/person. My apologies as well for its length.

I was surprised to see earlier today on the MOU website, that the Least Terns 
being observed in Rock County are now considered as "confirmed" breeders. 
This has also been included on the "Occurrence Maps" on the MOU website, 
prior to the birds even being voted on (and accepted) by MOURC. Wow.

The nature of this observation brought to mind similar circumstances of an 
observation by Karl Bardon, of an adult and juvenile Least Tern in Dakota 
County on 29 August 1992, as detailed in his informative article in THE LOON, 
v.64 #4. Note the date as being somewhat close to the present observation in 
Rock County. Therein he provides the following information: ..."The possibility 
that these Least Terns nested in the vicinity is considered. The observation of 
an adult bird feeding a juvenile may infer local breeding in some species (i.e. 
most passerines), but in many tern species, including Least Terns, the adults 
are known to occasionally accompany and continue feeding juveniles on 
migration (THE WILSON BULLETIN 71:313-322)." Kenn Kaufman notes in LIVES 
OF NORTH AMERICAN BIRDS, that juvenile Least Terns accompany adults for 
2-3 months after hatching. Well into migration timing.

Bardon continues with his very critical look at both birds' molt status, (which 
I'm uncertain has been attempted with the Rock Cty birds due to the distance 
involved) and concludes: ... "The adult Least Tern and this dependent juvenile 
could therefore have flown a considerable distance from the actual place of 
nesting." The same may be true of these birds as well. 

While I have been selective with the material quoted here, interested persons 
are encouraged to read the entire article. Karl is one of the most respected 
and knowledgeable birders in the State, and the article is an excellent read.

My intention here is to urge caution before jumping to conclusions. Perhaps 
there is additional information about this claim of "confirmed " breeding that is 
unknown to me. If so, please share it with us all. I would love to be proven 
wrong. Otherwise I suspect that claiming this as a new breeding species for 
Minnesota is more likely circumstantial or conjecture than fact.

Thank you.

Drew Smith
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