
Over the past week, I've visited Sax-Zim Bog on two separate occasions. The first visit was with a friend from Hawk Ridge. We saw some wonderful birds, including a Northern Hawk Owl and a Great Gray Owl,

Owls are unique and beautiful in their own way, but seeing them, in their preferred habitat is so cool! The Great Gray Owl and Northern Hawk Owl are both habitat specialists. A habitat specialist is a species that is found in a single/small variety of habit types. Northern Hawk Owls are typically a Canadian Boreal Forest species. Lucking for any nature-lover in northern Minnesota, there is a small stretch of Boreal Forest that stretches from Canada southward, along the North Shore of Lake Superior. Northeastern Minnesota is one of the few places in the entire lower 48 states to see Northern Hawk Owls!! Great Gray Owls love the Boreal Bogs, however they can also be found in mixed dense forests (thick deciduous over there.... coniferous over there... mixing in the middle) - yeah, that's what makes their home, their home. The most reliable spot to find these two owl species would be to visit a bog, and that's what Sax-Zim Bog consists of. A Beautiful Black Spruce Bog.


Triangulates? What the heck is that? The owl is actually hearing in 3-D! Here is how it works; Unlike humans, and most other living creatures that can hear, the owls have a unique ear setup (the ears are actually offset in non-symmetrical places on the sides of the head). It's a subtle difference, but by having one ear placed on the upper side of the head, and the other ear being lower on the opposing side, the ears will hear sounds at slightly different times. By having two ears independently located in different locations, the sounds that the bird hears will reach each ear at an ever-so-slightly moment. As a result of this, the owl not only hears how loud or soft something is, but also "hears" distance and depth. Here are two little tests that that you can do to see what I am talking about with the owls' unique senses.
Look at something complex in your house, maybe a cluttered desk, or a freshly-set dinner table, or maybe some birdfeeders out the back windows. Notice how you can see the far and close items, and get a sense of depth. Then, close one eye, keep looking at the same items, and notice how you cannot get that same depth perception. Your brain is only connecting a one-plane view to your eye, and that's what makes the view seem flat. Having two eyes open allow your brain to combine two angles into one "observed image," which produces the depth in what you see. The owl's ears work in a similar way with deciphering distance and depth. But, there's more that you have to do, in order to get a feel for what the owls hear!
Listen to some music, walk to the other side of the room that the music is playing in, and close your eyes. Relax. Cover one of your ears with your hand... wait a few moments, and try your best to point where the music is coming from. Tricky, huh? Your are hearing in a one-plane atmosphere. Now, take the one hand off your covered ear (eyes closed. no peeking)! Notice how right away, you get a sense of direction that the music is coming from? Now, even though this is beyond human, imagine combining the depth-deciphering

Triangulating is when the owls rocks the head back and forth, staring at once spot, to get a feel for "ok, with my head being here, the sound is that far. Now, with my head being a few inches over, the little critter is exactly there, under the snow." Now back to experiencing the Northern Hawk Owl...
So the owl triangulates, crouches, then freezes..... stands up again,


Good birdwatching,
Erik
Great article and photos Eric. Really interesting!
ReplyDeleteBrian Hansen
Thank you Brian :)
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