Saturday, October 6, 2012

Mexican Spotted Owls (and some cool facts about owl eyes)

Good evening all!  This week's owl is the Mexican Spotted Owl, a lesser-known resident of Colorado.  As I've never met one of these birds, I got most of my information (and all of my pictures) from online sources such as, but not limited to, the endlessly useful annals of Wikipedia.  (For the record, the Wikipedia entry for Spotted Owls is one of the most thorough and exhaustively-referenced articles I've ever read on that site, and I'm pretty sure a top-tier Spotted Owl researcher must have written it).
animalconnectionblog.blogspot.com
The reason I have never met a Mexican Spotted Owl is because we don't have them here in the Fort Collins area.  As a permanently disabled educational ambassador for the Rocky Mountain Raptor Program I do get to travel around the state a fair amount, but none of our journeys have taken us to southwestern Colorado, which is the only corner of the state that these beautiful owls call home.

There are three variations of the Spotted Owl, only one of which (the Mexican) lives in Colorado.  The other two are the Northern Spotted Owl (which claims the Pacific Northwest for its home) and the California Spotted Owl (I'm not going to bother explaining that one). If you're interested in reading more about Human-habitat-owl interactions, I recommend Googling the Barred Owl and the Spotted Owl and checking out the dynamic between those two species in the Pacific Northwest.
paulbannick.photoshelter.com
As for us, we're concerned with the Mexican Spotted Owl for now.  They're not terribly large owls, being comparable in weight and wingspan to the Common Barn Owl.  That means they weigh in around 1.5 pounds and have a wingspan of 3-4 feet.  Their name comes from the tiny white bars in the plumage on their backs and wings.  The bars are so small they pretty much look like spots.  They have strong facial discs, and large, dark eyes (more info on this below!). Their physiology makes them ideal nocturnal hunters, like most owls.  They prey primarily on woodrats, but also enjoy a tasty range of mice, rabbits, voles, and the occasional bat.
US Fish and Wildlife Service
Mexican Spotted Owls live in forests and canyons, and especially love forests in canyons.  As you can imagine, this can make it tricky to observe one in the wild. They nest either in trees or on rock ledges.  Since they live in such a specialized niche (forests in canyons, remember), small changes in the size of their territory can have big impacts on the species.  In the early 2000's it was determined that habitat preservation was critical to the survival of this species (they're on the Threatened Species List), and the US Fish and Wildlife Service succeeded in preserving 8.6 million acres of land for these birds in the Four Corners region, including 322,000 acres in Colorado.  The logging industry put up a fight, but the USF&WS service won in the end.
dwrcdc.nr.utah.gov
So, there's what I learned about Mexican Spotted Owls.  I'd love to tell you something a little more personal about their habits and behaviors, but as I said, I've never met one.  But along the way of researching these birds I did learn something else.  I can't tell you how many times I've wondered if eye color has significance among owls.  I, as a Great Horned Owl, have big ol' yellow eyes,  Barn Owls have dark, almondy-brown eyes, Eagle Owls have orange eyes, and the White-Faced Scops Owl has orangey eyes bordering on red.  And now here's the Spotted Owl, another bird with really striking dark eyes.  What's up with that?  And while I didn't find any answer to why they're different colors, I have determined that the different colors don't indicate whether the owl is diurnal or nocturnal, which is a common theory.
care2.com
The theory goes like this: yellow eyes = diurnal, dark eyes  = nocturnal, and orange eyes = crepuscular (active at dawn and dusk).  It is true that all dark-eyed owls are nocturnal, but so are most of the others.  With the exception of the Burrowing Owl (yellow eyes and largely diurnal), all the yellow-eyed owls are also nocturnal, including Great Horned Owls like me.  However, yellow-eyed owls are a little more active during the daytime than dark-eyed owls are. While birds like the Mexican Spotted Owl take cover during the day and don't come out unless they really have to, owls with yellow eyes are a little more willing to venture out during the day. But that's it.  Hope you're not too disappointed.

Along the way of researching owl eye colors, I learned more cool things about my eyes than I know what to do with.  For instance, I've always known that both my upper and lower eyelids move when I blink, but I didn't know that owls are the only raptors that do this (all the other raptors just blink with just one lid).  I also learned why my beak is so low on my face compared to other raptors:  owls' eyes are so big that if our beaks were any higher they would get in the way of our eyesight!

That's all I have for you this time.  Tune in next week to learn about the Long Eared Owl!  As always, you can email me with questions or comments at talonsofdoom@gmail.com, follow me on Twitter @RaptorProgram, check us out on Facebook (Rocky Mountain Raptor Program), and find out more information and stories on our main website (which is brand new and shiny!).  If you would like to subscribe to this blog, use the box in the toolbar to the right.  Thanks for reading and supporting the RMRP!

3 comments:

  1. I think I've spotted an owl in flight along the coastline in Cozumel...is it possible that this would be a Mexican Spotted Owl? There is plenty of jungle here, but zero canyons, and they seem to be more of an arid climate raptor rather than a jungly one. Neat article!

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  2. Oddly enough, Mexican Spotted Owls only have a little bit of territory in Mexico, and it's all in the Chihuahuan highlands. Cool that you're seeing a jungle owl, though. I wonder what it is?

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