Sometimes there are clear and obvious reasons that birds wander into very unusual territory.  In the case of the Northern Hawk Owl, for example, they tend to get pushed south when their natural food supply is weak in North American Boreal Forest so they are pushed south.  

This is not a frequent occurrence, but it does happen from time to time.  Last year, there were Northern Hawk Owls spotted throughout New England when there hadn’t been one identified in the region for nearly a decade prior.  We also had enormous numbers of pine siskins routinely in our yard, when I’d never seen more than one or two at a time before.  (at one point, we counted over 150).

And then there’s this guy:

The bird doesn’t look that much like anything unusual, but the black-tailed gull is not a bird that hangs out in an entirely different part of the Atlantic.  It hangs out in an entirely different part of the Pacific and, for some reason, in October of 2005 it hung out in Lake Champlain (Eastern US, between Vermont and New York).  

I remember this in particular because it was when we first realized we weren’t just kind of into birding, but really into birding.  We drove more than 6 hours just to see an unusual gull, and we were really happy we did it.

But the next rare bird chase was the one that verified it.   The Western Reef Heron is a bird that has only been identified in the United States four times.  We went to Kittery, ME, to find it,  It took us the better part of the day.  We got there early and it wasn’t in its usual harbor.  But there were birders everywhere looking for it and that’s when we realized that birders are kind of awesome.  Not only did people help us with tips, people who recognized us from the morning pulled over to give us leads when they spotted us down the line.  When we finally found the bird and got good looks at it, it was entirely because other birders led us there.  I remember one point at which we had the bird, but it flew across the harbor.  Then someone spotted a group of birders on the other side of the water getting really excited, put his scope on them to see where they were looking and then we all ran to our cars (“to the birdmobile!”) to get to the new spot.  Eventually I got some photos of the bird:

notice that there are two birds in that photo.  The white morph of the western reef heron is extremely similar to the snowy egret shown next to it.  We suspect that it simply ended up with the wrong flock, following around a bunch of snowy egrets, assuming they were its kin.

Other birds are not unheard of, but very uncommon.  This rufous hummingbird, for example…

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…is believed to be trending east.  We’re seeing more frequent sightings of them on our coast, but it was still a real treat to find one close to home:

Things get weirder when it comes to nesting behavior.  This Mississippi Kite not only decided to visit Newmarket, NH.  It actually decided to start a family.  It had an active nest in the area and successfully fledged chicks:

But right now, my favorite of these unusual migrants is the Sage Thrasher for one fairly simple reason: I saw my first one yesterday.  A Western Bird, for some reason, has shown up in Salisbury, MA.  Here it is feeding on juniper berries:

There are lots of reasons that birds end up off their usual paths.  In some cases, we have irruptions, which are mass migrations beyond the normal territory to look for stronger food sources (note the siskins I referenced before).  This is especially common when there is a boon year for a bird’s food source, followed by a weaker year produces larger numbers of birds than usual, with less food to share, forcing them into new territory.

But that’s generally a minor expansion: a few hundred miles further south than usual.   Crossing a whole continent?  A bird which winters in the Baja Peninsula showing up in frigid New England?  A Japanese bird showing up in Lake Champlain?

I don’t know what causes this.  It might be a bird that just wanders off its path.  It might be a bird that was taken as a pet and released.  It might simply be a bird having been stuck in a cargo hold for a couple days until it found a way out when the hold was opened.  

I really have no answers to this, but I love these opportunities to see things that are almost unheard of in my territory.  Sage Thrasher?  I vaguely remember having heard of one before but until this week, it was completely off my radar, and as of yesterday, I’ve got a new life bird.  

I’ll close with a photo I’ve posted many times before: the earlier referenced Northern Hawk Owl