Tree Swallow Question

[ajh]

I've had a lot of success attracting martins and tree swallows and bluebirds to several sites...however none to my own back yard as it's in town and has had too many trees. As the years passed by, many of the trees in my yard and the neighbor's were removed. Last year I was pleasantly surprised to successfully attract and host a pair of tree swallows in a bluefird box. They arrived pretty late for here in Northwest Ohio...about the first week in May and successfully raised and fledged 5 young. The box they used is about 25 ft from my gourd rack. I've dealt with the "tree swallow emergency" at other sites many times by moving the chosen gourd off of the rack to a shepherds hook so I'm not too worried about that.

My question is about the tree swallows late arrival. Do you suppose they were SY birds and like SY martins arrive about a month later than the ASY tree swallows?
Since they were successful here last year, do you think I'll get them back again this spring and if so will they arrive about a month sooner?

thanks,
ajh

[Rafke77]

I get a lot of tree swallows and blue birds as well, although I don't know if they're repeats from the year before. Just from my observations here in northern Indiana, tree swallows always come a few weeks before my martins. I tend to think a lot of people confuse them with martins as I've noticed on the scout arrival map people are posting sightings all around me and far north, but none at my resort, I could very well be wrong and maybe mine are just taking the back roads here .

Anywho back to your question, it would be hard to tell unless you find a unique looking one to watch for the next year, or know someone who can band some of the babies. I'd imagine they would be similar to martins and always return to the same area.


-Rob

[randyM]

I too host many nesting tree swallows along with purple martins on my property. Without banding or uniquely marking individual birds it is just a guess if individuals are returning to a specific location from one year to the next. I'm fortunate to have martins banded at my colony as part of a larger study and have observed returning individuals (some 5 years and counting), but do not have approval to band any tree swallows at my site. However, according to the Cornell Lab of Ornithology some tree swallows have been documented returning to the same nesting cavity year after year, sometimes pairing with the same mate. The breeding pair likely doesn't overwinter as a pair, but may both be drawn to the same nesting cavity from the previous year and pair up again the following nesting season. Annual mortality is fairly high for small birds and the likelihood of both individuals of a pair returning to the same nest cavity is probably less than 50% from one year to the next. I have about 90 nesting tree swallow pairs on my property each year and the earliest arrivals usually outpace the earliest martins by about a week on average (April 8 vs April 15). I have noticed that most SY female tree swallows arrive and nest a few weeks later than many ASY female tree swallows at my site. During the breeding season most SY female tree swallows are noticeably more dull in appearance than any male tree swallow, or ASY female, as ASY females are almost identical in luster when compared to males of any age during the breeding season. So, if you notice a nesting pair of tree swallows where one of the individuals is noticeably more dull than the other, it would be likely the duller individual is a SY female.