Saturday, November 18, 2017

A Most Unexpected Irruption plus Sparrows of the Eastern US

[Southeast Michigan. Spring/Summer 2017]

Predictability and balance are the cornerstones of what passes as normality. A state that, uncontestably, marks our preferred state of stable, daily existence (or dare we say "drudgery"?) . 


However, it is the very unpredictability in birding that imbues it with the thrill of discovery. And, except perhaps the occasional rarity chase, there is seldom a more thrilling occasion in birding than the mystical event known as an "irruption". Irruptions are caused by an ecological imbalance that results in a sudden upsurge or "invasion" of a species into a region where they are normally absent. 


The astute reader will surely be profoundly aware of the Razorbill irruption in the Gulf of Mexico that this blogger had the distinct pleasure of witnessing in the Winter of 2012. And, now, we are pleased to report on the irruption of Dickcissel into Southeast Michigan in the summer of 2017 -- the full list of species includes this iconic species plus a delightful collection of sparrows:


  • Dickcissel
  • Eastern Towhee
  • Field Sparrow
  • Song Sparrow
  • Swamp Sparrow
  • Savannah Sparrow
  • White-throated Sparrow
We start with what appears to be a grosbeak-like, sparrow-colored songbird:




Seen at the I-94 Service Road in Macomb Co., this was a maiden sighting of this species for this blogger. A species of prairie grasslands in the American heartland, this songbird's last irruption to this region was in 2012.





Various theories have been postulated as to the reasons behind an irruption -- a shortage of food, or a drought; maybe climate change and warming temperatures, or perhaps lack of suitable nesting conditions. Whatever the reason, their arrival is celebrated and observation opportunities fully availed.

Next, a large sparrow - the Eastern Towhee:






A loud songster, this sparrow with a bold black hood, red eyes and brown flanks is hard to miss.





Field Sparrows give themselves up by virtue of their "bouncing ball" song. A thin white eyering and pink bill and legs are also distinctive.






Far more commonly found is the 
Song Sparrow:







Swamp Sparrow is aptly named and never found far from marshy areas:



Savannah Sparrow, on the other hand, is seen in grassy areas:








Finally, White-throated Sparrow was observed in migration at Lake St. Clair:




These bold sparrows can be fairly common in migration:




Baltimore Oriole is our bonus bird. Here seen at Wetzel SP.



The underlying causes behind ecological forces are not always clear to us. However, the resulting symptoms -- such as irruptions and invasions -- are not only observation opportunities but also natural history events that warrant further scientific investigation.

1 comment:

  1. Your photos are an artist's delight! I was looking for any decent photo of two birds to look at, needing to know what a Hooded Warbler and a Brown Creeper look like, for a piece I am drawing for a friend's Chanukah present, and came across both birds at your site. What marvelously clear and beautiful photos! As someone who despite being able to draw has trouble seeing, these were a dream come true as each detail is clear that I needed for my renderings.

    I am curious, though, as I could not find it on this page, what is the bird above, nestled among the dried teasel? (Not being any sort of birder, I can only guess as to its name, perhaps a Baltimore Oriole or a tanager? But truly I do not have any idea...) Thanks for this miraculous website in any event. My best to you, Pamela Wagner

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