Friday, March 30, 2012

Why Swainson's Hawks Are Cool


Oh, gee, what to say about Swainson's Hawks? A lot of the Swainson's Hawks seen at the RMRP are immatures, and like most immature raptors, they're a little...um...doofusy.  The adults, on the other hand, are truly a hawk to be reckoned with, mighty prairie predators. 

John C. Avise
Probably the coolest thing about them is their migration: these birds are the most well-traveled of us North American Raptors, flying a whopping 14,000 miles each way just to snack on grasshoppers in Argentina each winter. Personally, I don't see the allure in eating insects, but Swainson's Hawks really go nuts for them, and really only hunt other food (mice, voles, etc) during breeding season when the chicks need the nutrition. 

Their migration route takes them south through the Great Plains, along the Gulf of Mexico, straight down Central America, then along the Andes to Northern Argentina. Then they hang out there for the winter months, gorging themselves on grasshoppers, speaking Spanish, and bracing themselves against the pampas winds, before turning around and flying all the way back here to breed in the spring. Then they come into the Rocky Mountain Raptor Program with an injury of some type, and they're all, "¡Che, bolodu!" and " ¡Buena onda!" Crazy, right? I guess us Great Horned Owls are homebodies in comparison. 

John C. Avise
Swainson's gather together in giant groups called kettles before flying away on migration. When the RMRP releases all the immature Swainson's Hawks they've collected over the summer, they release them into these kettles so the inexperienced kids have other birds to follow south. The Humans have reported success with this method, based on seeing which banded birds make it back north over the following years. 

Here in Colorado they spend most of their time on the Plains. They build their own [poorly constructed, low-quality] nests in clusters of trees on the plains. These nests often blow down in wind storms and the like, which is the source of most of our Swainson's Hawks here at the RMRP each year. However, I can't judge their nest building skills too harshly, seeing as Great Horned Owls don't build nests at all--we steal them. Muahaha. 


Many years ago, back in the 1970's, the Swainson's Hawks suffered a blow to their population when farmers in Argentina began using DDT and monochrotophos as insecticides on their fields. The Hawks feasted on all the dead [poisoned] grasshoppers and locusts, and experienced a pretty big die-out as a result. But Humans in the US and Argentina worked together to stop the use of those chemicals on the fields, and the Swainson's Hawks have recovered nicely. 

It just occurred to me: maybe residual effects of mass poisoning are what make the Swainson's Hawks such space cadets? But, again, even their air-headed-ness is awesome: I can't tell you how many times I've overheard a Human go into a cage to catch a Swainson's Hawk (assuming an easy catch), then comment in surprise as the bird nimbly escapes capture, or sinks a talon into someone's arm. They may be a bit goofy, but they're still definitely Raptors. 

They're due to be arriving any day now, so when you see your first one of the season, take a moment to think how long they had to fly just to get back home to beautiful Colorado. Maybe congratulate them on a migration well-flown, or remind them to build their nests out of sturdier sticks this year. 

Next week: Osprey!  

Monday, March 26, 2012

Snarge

Yes, that's right. Snarge.

A reader sent this article to my email (talons of doom (one word) @ gmail . com) after it came up in conversation with a pilot. It ends up that raptors and airplanes encounter each other more often than I ever imagined!

Snarge is what remains after a bird-plane collision. Whenever such a collision occurs, the Humans in the plane send some of the snarge goo to the Smithsonian Institution, and they analyze it to see exactly what hit the airplane (or what exactly the plane hit?). They're hoping to use the information to decrease the amount of collisions in the future.

What's really interesting is that it's not just birds who hit planes! The Smithsonian scientists also find rabbits, fish and other prey items, presumably dropped by raptors, herons and the like.

The most damaging birds are, in this order, Turkey Vultures, Canada Geese, and White Pelicans. The most common are mourning doves and horned larks.

Who knew? I'll try to warn birds we release to keep an eye out for low-flying planes!

More detailed information can be found in this article.


Thursday, March 22, 2012

Quick bird update


  • The adult Bald Eagle with the spinal trauma and confidence problems was put out in a large flight with the immature eagle for a week to help the immature calm down. It worked well, so now the adult is back in a smaller cage where she can continue working on attaining higher perches. See how tall she's getting?
  • The American Kestrel that came in with a fractured ulna is flying perfectly and should be released as soon as the wind dies down!
  • The Red Tailed Hawk that was found with its head stuck in the grill of a truck is doing really well. His skull fracture is healed and he's flying around his cage really well, despite having reduced vision in one eye. Next step: rat school, where the hawk is moved to a large flight and given live rats to kill. If his vision and flight are good enough to hunt and kill, he can be released! 





All the other birds at the RMRP are doing well, too. The case load is slowly climbing as we approach summer. I'll let you know when more interesting cases come through the door!

Tuesday, March 20, 2012

Why Turkey Vultures Are Cool

As I mentioned a few days ago, I've decided to write a profile of each of the Raptor species we often see here at the RMRP. I plan on getting the information primarily from interviewing birds here at the RMRP, with supplemental goodies from Wikipedia.

First up on the list, simply because they're due to arrive any day now, is the awesome and amazing Turkey Vulture.

As a general statement, Humans really seem to dislike these birds. That is, they dislike them until they get to know them--then they love them forever. I think it's the whole "carrion thing" that deters the Humans, but once they understand how the "carrion thing" is part of a whole suite of really hootin' cool evolutionary adaptations, they seem to come around. So, in an effort to help the Humans who read this blog learn to love Turkey Vultures more quickly, I'm going to write about all the neat things Vultures have going for them.

Since I've already mentioned the "carrion thing", let's start there. Or, even more basically, let's start with this little fact: Turkey Vultures are not Raptors. A Raptor is defined by (anyone? anyone?) how it uses its feet to catch and kill its prey. Turkey Vultures (like most Vultures) don't have big strong feet like Raptors because they're not concerned with catching and killing prey. They're too smart for that (or so-say the resident Turkey Vultures...I think I'm plenty smart, and I killed a rat the other night). Instead, they find animals that have already bitten the dust, and eat them.
jeffreyagordon.com 

The way they find these dead animals is pretty cool. First of all, they have a "sense of smell". Not really having one of these myself, I'm not sure how to describe it, but I know that Turkey Vultures are pretty unique in their ability to smell ethyl mercaptan, a chemical emitted during decomposition, from such huge distances. Humans can smell ethyl mercaptan at 2.8 parts per billion. I haven't found the number, but Turkey Vultures can smell ethyl mercaptan from as much as two miles away--how many parts per billion is that?!  As an interesting aside, Humans add ethyl mercaptan to natural gas so they can smell it if there's a leak, and leaks in gas pipelines are often discovered early by circling Vultures.

More about Turkey Vultures and carrion: they spend their days soaring around on their broad wings, hardly flapping, until they detect some ethyl mercaptan in the air (or they see other circling Vultures in the distance). Then they slowly fly down, land and feast. That's where the other adaptations come in: Turkey Vultures have featherless heads so that they stay clean while dipping their heads into body cavities; and in addition to helping them detect smells, their nostrils (called nares on birds) go clean through their face so nothing can get clogged in there.

Now, imagine you're a talonless bird standing on the ground around a carcass, trying to eat your lunch...except all the other scavengers want it too...and they're bigger than you. What will you do to defend yourself? Turkey Vultures have a simple (if gross) solution: they regurgitate partially-digested rotting meat. Humans claim that the smell is vile, and it works well at deterring predators.

aviandissuader.com 
Alright, enough about food, time for intelligence. Turkey Vultures are endlessly curious and inquisitive. Hinges? Open them! Feeding mat? Turn it upside down and fold it into a wonton! Shoelaces? Untied before you know it! They learn quickly and remember forever, and they always test their limits. The Humans are always talking about how they can't flinch when an educational Turkey Vulture tries biting the soft fleshy bit of the arm just above a glove, or else the Vulture will remember it and never leave the Human in peace. Intelligence comes with a price.

And, finally, let's talk about how good they look. Seriously, Turkey Vultures are some of the handsomest birds, with their bright eyes and rosy skin. Don't get me wrong, my tastes lie more with large yellow eyes and a deep hoot, but there's no denying the dapper good looks of a Turkey Vulture.

A few more tidbits: Turkey Vultures migrate in enormous flocks called kettles; they roost communally at night, then catch the thermals to go soaring around in the morning; they mute (poop) down the backs of their bare, featherless legs and let the evaporation of the urates cool them off; their heads are greyish black for the first two years, then turn red when they become adults.

lansingwbu.blogspot.com 
The RMRP has two educational Turkey Vultures. One of these is young and mischievous, always looking for a shoelace to untie and a new volunteer to intimidate. The other is referred to as the Old Male. He was admitted to the RMRP in 1988 as an adult bird. That makes him at least 25years at this point! That well exceeds the wild lifespan of 16 years. The Old Male isn't as much of a troublemaker as his counterpart, but he still keeps an eye open for exposed flesh.

So, there are some cool facts for you. And as the Turkey Vultures make their ways north, slowly winging towards Fort Collins for the summer, I hope you look forward to their arrival more than usual. Not only are they the harbingers of spring, they're also perfectly evolved creatures here to clean up the icky rotting carcasses of the world. And they're interesting to boot.

Next bird profile: Swainson's Hawks! Check back next week.

Monday, March 19, 2012

The Interloper: Victory is mine!!

3...

There was no moon tonight, just pale starlight and the orange glow of city lights. When the whiskers appeared in the hole, I didn't see them at first: I heard them. A faint rustling noise, quieter than a distant breeze, but I was already on high alert so I heard it. I bobbed my head, focusing in on the delicate motions in the darkness.

2...

I remained perfectly still on the perch, staring intently, waiting for the rat to become bolder, move out more. It only took a few seconds, then he was out in the open, scuttling towards a few leftovers from my dinner (rabbit and duck). I spread my wings, launched gently from the perch, and...

3....

Victory tastes like rat.

Thursday, March 15, 2012

Buzzard Day!

Now that you have all been educated about the term "Buzzard", it's time to celebrate the annual arrival of the "buzzards" (ahem, Turkey Vultures...) in the town of Hinckley, Ohio.

Each year on March 15th, the Humans of Hinckley gather at 6:30 in the morning with binoculars and coffee, each trying to spot the first arriving Turkey Vulture of the year.


See, Turkey Vultures are migratory. Each year around September they form into large groups called 'kettles' and fly south for the winter. Their bare legs and heads just can't keep them warm during the cold US winters. So they cruise on down to Mexico and Venezuela and the like, where they soar on jungle thermals and feast on the flesh of dead...monkeys? Then, in the spring, they return to the US for the warm weather and different selection of carcasses.

In the town of Hinckley, the Humans understand how awesome and incredible Turkey Vultures are*, so they celebrate their arrival each year with Buzzard Day. It's considered the official start of spring for them! March 15th was selected as the day for this fiesta back in the 1950's, when for six years in a row the first Turkey Vulture arrived in town on March 15th. It doesn't always happen on that day, so the inhabitants of Hinckley just pretend they didn't see that Vulture back on March 11th...

I haven't yet seen any Turkey Vultures here in Fort Collins this year. Have any of you Humans? Because I agree with Hinckley: when the Turkey Vultures arrive, spring is here. Of course, there are other migratory Raptors I could use for that same purpose (the Merlins and the Rough Legged Hawks should be heading north now, and the Swainson's Hawks will be hot on the tails of the Turkey Vultures), but there's something about the uniqueness of Vultures that makes their arrival more notable. More 'springy".

Now, even though I support the idea of Buzzard Day in Hinckely, I had to ask: where is a town celebrating Owls? Unfortunately I asked this question too late, as the International Festival of Owls in Houston, Minnesota just happened a couple of weekends ago. I don't know how I'll make it happen, but next year: I'm going.

In the meantime, Happy Buzzard Day!


*Telling you about how cool Turkey Vultures are will have to wait for another article. In fact, I think I'm going to start giving a profile on each of the amazing Raptor species seen here in Colorado, maybe one a week. Stay tuned!

Wednesday, March 14, 2012

Tuesday, March 13, 2012

Raptors in the news: eagles vs turbines research

Looks like the frequency of eagles colliding with wind turbines has spurred some research by the USDA. I like the idea of "tiny bird backpacks" to monitor them!

Monday, March 12, 2012

The Interloper returns

I think my gruesome haikus and limericks must have scared off the furry beastling, because my cage was devoid of rodent activity for a couple of weeks. But just a few minutes ago, while I was lost in the hooting of a handsome male Owl outside my window, the rat made a run through my cage! I only caught the tail end (ha!) of him as he darted back into his hole.

How is it that even as a mature and experienced Owl, many seasons old, I can still be so easily distracted by a good looking male with a clever turn of phrase? I missed out on an easy kill. The Grey Female would be sorely disappointed in me.

Alright, time to buckle down. Less flirting, more death. Yes. That's the ticket.

Saturday, March 10, 2012

As promised

Here are photos of some of the birds I wrote about the other day:


One week later, doing much better!

The Red-Tailed Hawk who was found with its head stuck in the grill of a truck:
In the O2 cage after admission


The Great Horned Owl with the healing fracture, the one who is very angry and fierce:



The female American Kestrel with the healing fracture (she likes to hang out in the highest corners of her cage):


Sorry, I didn't have time to snap a pic of the Bald Eagles, but I'll try to get one soon!  I'll keep you posted on everyone's progress! 

Heartbroken

Today we lost the best one of us all. The Grey Female Great Horned Owl came to the RMRP as an adult bird 18 years ago.

She was a beautiful beast and she will be greatly missed.



Instead of words, here's a song. Just click the little blue play button on the page that opens.

Wednesday, March 7, 2012

Q&A Corner

Good afternoon! A reader of this blog asked a follow-up question to last week's Q&A (the question was about pseudonyms for birds). She asked if I could please explain the use of the word "buzzard". Absolutely!

Buzzard is a common word that is used two different ways. The different uses are not right or wrong, just different, but they can cause some confusion:


Common Buzzard

  • Buzzard - Old World:   In birding terms, everything east of the Atlantic Ocean is considered the Old World, while the Americas are the New World*. And in the Old World, especially Europe, the word buzzard means hawk. More specifically, it refers to broad-winged hawks, or buteos. Even more specifically, it refers to the Common Buzzard, Buteo buteo. In American terms, it's like a causal observer glancing up in the sky, seeing a broad-winged raptor soaring around and saying to her friend, "Hey, a hawk!" and the friend replying, "What kind of hawk? A Red-Tailed Hawk?", except they would say, "Hey, a buzzard!" and the friend would reply, "What kind of buzzard? A Common Buzzard?"   


      Turkey Vulture, sometimes called a buzzard'
    • Buzzard - New World:  Here in the U.S. 'buzzard' has a different meaning altogether. When we say buzzard, we mean vulture. Since the only two  vultures we have flying around our skies are the Turkey Vulture and the Black Vulture, that's usually what is meant by buzzard. Also, buzzard is sometimes used as a derogatory term for a Raptor, like, "Look at that buzzard on that telephone pole, just waiting to eat my chickens!"  



    • Buzzard - not Raptor related:  Then there's the colloquial use of  buzzard to describe someone contemptible or bloodthirsty. I'm sure that has its roots in the [undeserved] bad reputation of vultures. In a sentence, you could say, "That old buzzard behind the front desk is just trying to ruin my day!" 

    An amusing exercise to see how commonly the word 'buzzard' is used in its various forms is to do a Google image search for 'buzzard'. You'll see an interesting mix of hawks, vultures, cartoon vultures, and one guy with blood on his face who was obviously on the receiving end of some talons. 

    Thanks for the question! Anyone who wants me to answer a Raptor-related or completely non-Raptor-related question, just send an email to "talons of doom (one word) @ gmail . com"


    *Please note that Australia, New Zealand and the rest of the South Pacific are apparently world-less. 

    Tuesday, March 6, 2012

    Rehab gossip

    I just got back from eavesdropping on this week's Rounds meeting. Once a week, all the Humans who work and volunteer at the RMRP gather together in the warehouse to ensure there are enough minions on every shift to take care of all of us Raptors, to make announcements, hand out awards and certificates, and go over the ever-changing status of all the rehab cases in the facility. Tonight's updates had me making notes in my iPhone because, for the first time in a couple of months, there are enough birds in-house to cause information-overload while listening in. Here's the quick and dirty of some of the more interesting cases:

    • Remember the Bald Eagles I mentioned a few posts ago? The slow-but-steady spinal trauma adult, and the reckless youngin' determined to knock himself senseless by forgetting to put on the brakes? Well, the  youngin' had to take a breather from the large flight cage when his lead poisoning flared up again, but he's back in a large flight cage again...and guess who's there with him? The slow-and-steady adult! Her progress has been really positive recently, so she was moved into the large flight cage with the reckless kid in the hope that she'll help him chill out a little. They're also helping each other with physical therapy: he always wants to be next to her, and she always wants to be left alone. So when she moves to a perch and he follows her there, she moves to another perch in an effort to get away...and so they're always moving and always giving themselves physical therapy. Don't worry: even though she doesn't want to be buddy-buddy shoulder-to-shoulder with him, they're actually getting along just fine. 
    • A Great Horned Owl came in a couple of weeks ago with a fractured humerus. That can be a very bad thing, but this was the kind of break that made the Humans happy: a clean, simple, middle of the bone fracture. He has a fixator on it for support, and he's confined to a critical care cage until the bone heals. Since the fracture was an easy one to deal with, this Owl is making up for it in other ways. One, he's a chewer, and the Humans are spending a lot of energy creating chew-tabs out of tape for him to gnaw on instead of the fixator. Two, he's a handful. Now, all Great Horned Owls are angry, disagreeable handfuls (and we're very proud of this), but apparently this guy is angry above and beyond the norms. I can't wait until he moves to the outside cages and I get a chance to chat with him! 
    • A Red-Tailed Hawk, hit by a car, came in a week ago in really bad shape. Of course you expect a hawk hit by a car to be in bad shape, but this hawk was stuck in the grill of a truck. By his head. And did he give up an die in the grill of that truck? Heck no. He's a Red-Tailed Hawk. They fight. This guy has massive head trauma (no surprise there) and a fractured skull. Recently he's regained enough coordination to eat on his own (I remember how hard that was for me back when I was admitted for head trauma, and I didn't have a fractured skull!) and the vision in his left eye is slowly improving. The outlook on this hawk is still guarded, but I'm really pulling for him. What a fighter!
    • A few weeks ago a female American Kestrel was admitted with a fractured ulna. Again, this was a break that was cheerfully received by the Humans because it appeared to be fixable. When the ulna breaks, it can often be stabilized by the radius alongside it, which is exactly what happened in this case. She moved out to a small outside cage this week, and will be moving to a larger flight cage soon. The resident educational Kestrel with the Twitter account will be bummed to see her move--he's pretty smitten with his new neighbor! 
    Well, that's it for now. I'll try my best to sneak some pictures soon so you can see these birds I'm writing about! Of course, stay tuned for more updates, and I'll be sure to let you know when any of these brave birds get released.

    Friday, March 2, 2012

    Seeking new minions

    The last wave of new minions (the Humans call them "volunteers") that joined the Rocky Mountain Raptor Program in January have been progressing nicely through the Level H training. While that's great for them (now they can prep food and go into cages without supervision) it's not as fun for me as when they each entered my cage for the first time, tentative and scared, staring at me like I was going to eat them if they took their eyes off me for a second. Now they enter the cage with a sort of gentle confidence, and they can tell just by looking at my body language whether or not I'm going to fly from my perch. They're not scared any more. And where is the fun in that?

    Fortunately for me, the RMRP accepts new volunteers every other month, and this Saturday is the New Volunteer Orientation for March. It's from 10:00 to 11:30 here at the main facility at Vine Drive. Please come and learn about volunteering for us, and bring a friend, son, daughter or spouse to volunteer with you! Did you know that we allow children age 12 and up to volunteer here with a parent/guardian?

    Not only does the RMRP need the help (baby season is right around the corner), but I need the thrill of striking terror and awe into new minions entering my cage for the first time.

    Hope to see you on Saturday!

    Thursday, March 1, 2012

    Strange Humans

    While I was out for enrichment the other day, I saw some of the RMRP's minions passing around an iPhone with a picture on it and laughing over what they saw.

    Naturally, I "borrowed" the phone to see what all the fuss was, and this is what I found:


    Okay, Humans, that's not weird at all...