Baby Owls Branching Out

I'm in the midst of my busies month.  If I'm not at the National Park Service engaged in ranger work, I'm on the road at a bird festival, birding the crap out of whatever state I'm in.  It's a horrific schedule but it's loads of fun.  And at the end of the month of May, I get a weekend off to celebrate my wedding anniversary with Non Birding Bill (we'll be on year lucky 13--boy, why did I think it would be a good idea to get married in May?). A friend of mine who is new to birding asked if I'd like to go out next week.  My first answer was that I was too busy.  But then I saw on Tuesday that it was supposed to be 80 degrees and I just couldn't say no.  So we did some birding near my apartment.  It's warbler season and they are dripping off the trees.  The few days I was home, I had a golden-winged warbler outside my bedroom window ever morning!

I showed him the owl nest and boy the two young owls were panting like crazy.  Birds don't sweat like humans and pant like dogs when their hot.  The young owls still have some of their thick down that protects them in snow storms when they hatch earlier.  Doesn't it look like it's saying, "Oh man, I'm so hot, ugh."

I didn't see either adult and figured that since the young were so large, they were tucked in a nearby conifer for shade from the warm sun.  As I looked at the nest from this angle, I realized how trashed it is.  Check out these photos from an earlier entry when the female was still incubating.  Note how the nest material was all the way to to the stick.  In the above photo, it's well below that now.  I thought to myself that these owls have to be in the brancher phase.  That's when they are still downy but their feet are very strong and they begin to venture out of the nest.  The young birds can even be blown out of the tree, yet their feet are strong enough to enable them to climb back up.

It looks like they have some feather development on their wings and back.  I got confirmation on this a few days later from another nearby resident who has been watching the nest and he confirmed that babies had crawled out and were on branches 10 feet from the nest.  Our little guys grow up so fast.

Cooper's Hawk Attacks Owl Nest

Well, Friday morning turned out to be far more exciting than I anticipated!  I had to work at the park service in the afternoon and evening and I was meeting a friend for a late breakfast.  I thought that since it was warm, I'd peek at the great horned owl nest in my neighborhood and see if the owlets were more visible...

One owlet was easily visible with the naked eye on approach.  Great horned owls do not build their own nests, they take over old squirrel, hawk or heron nests.  They don't even make any renovations before they use it, they just squat.  As the chicks grow, the nests soon shrink.  Between the dwindling nest and the larger chicks, the female no longer fits very well and perches near the chicks.

It appears that the nest contains two owlets!  When I arrived to the general nesting area, I could hear the crows heartily mobbing.  I saw the male fly over with a flock of about 20 crows in tow.  The chicks showed a bit of interest in the commotion but mostly laid low.

The female was very interested in the crow activity as she watched the crows surround the other owl.  What was interesting was that I thought the crows were chasing one owl, I later ran into a fellow birder who was close the crows and he said the crows were after two great horned owls and a third flew in.  I wonder now that as I was watching her keen interest in the crow activity, if she was responding to an intruding great horned owl into her territory rather than the corvids gathering around her mate?

She soon left the nest to try to get a better look at the mobbing crows but still would turn around to keep an eye on her chicks.  It was so strange to me to see a secretive owl perched out in the open in the middle of the morning.  Not long after I took this photo, she bolted off into the middle of the flock of crows.  The owls all went in separate directions and the crows split their murder into 2 smaller groups, diving and cawing at the owls.

With the female away, the young owlets closed their eyes and assumed an upright position.  I wondered if this was all part of a camoflauge instinct?  With the adults going after the crows, it stirred up the surrounding birds.  Robins began giving their alarm calls and then an adult Cooper's hawk flew in.  The hawk missed its intended prey...then suddenly noticed one of the owls and started diving at it and screaming its call.  If you're not familiar with a Cooper's hawk mobbing an owl, let me remind you of the video of the Cooper's hawk mobbing a plastic owl (they never work to scare birds away).

The Cooper's hawk then made a wider pass and went straight for the owl nest, hell bent on mobbing the chicks.  First it bounced off the nest and then started to make a second dive, by that time, the female great horned owl was back on the nest and ready to kick some serious accipiter ass if it tried it again.  I have never seen a great horned move so fast in my entire life.  I've always referred to them as the Sunday drivers of the raptor world...I got schooled--they can move very fast when they need to.  The above photo is on the Cooper's hawk's second attempt at a dive on the nest.  The blur above the nest is the female owl defending her chicks.

The angry Cooper's hawk perched nearby and shrieked out angry, "kek kek kek kek kek keks" at the great horned owl.  I suspect this bird has a nest nearby.

The great horned owl stood at her nest above her chicks and hooted back her retorts after every kek the Cooper's hawk gave her. The owl even barked a few times in warning at the hawk.  It was the weirdest argument I'd ever heard.  As the two continued, a few crows gathered nearby to continue their remarks on the two predators they detested.  Then, out of nowhere, a broad-winged hawk screamed nearby.  Three raptors all at once! An owl, a buteo and an accipiter.

The chicks nestled against the female as if to say, "Yeah, my mom is awesome."

I wondered, how long was this battle going to last?  The suspense was killing me...then I got my answer.  I heard a helicopter coming fast and approaching low.

This was not digiscoped, this helicopter was THAT low.  It was Metropolitan Mosquito Control dropping their corn pellets full of Bti and Methoprene to kill of mosquito larvae.  The helicopter skirted the tops of the trees, the owl, crows and hawk scattered.  The adult female owl apparently thought, "Cooper's hawk, yeah, I can kill that," but when the helicopter appeared her attitude shifted to, "yikes, too big for me kids, you're on your own, see ya!"

After the raptors scattered, pellets rained down and bounced off my body.  I could hear nearby woodpeckers give low warning noises to each other.  Robins were on high alert.

A couple of nearby mallards seemed to dig the pellets and tried to eat them as soon as they hit the water--they were the only birds who seemed to be unaffected by the strange aerial machine.  The city assures me that the pellets are harmless both to me and the wildlife that might consume it.  I was tempted to start running around like Cary Grant in a Hitchcock movie, but it's not so much fun with a spotting scope in tow.

The helicopter made a few more passes and a few moments later, one of the owls flew back with a few pesky crows hot on its tail.

She perched right above my head and the crows still followed.  She looked over to see her chicks were still in the nest and I think scan for the Cooper's hawk.  Most of the crows lost interest, but a few hung around to caw out their angst.  I couldn't stay, I had to get to my breakfast meeting, but things seemed to be settling down and I'm sure she went back to the tree.  After a Cooper's hawk and a helicopter, crows were merely an annoyance.

One of the chicks was scratching itself, but it almost looks like it's trying to give a high five.  Note the large gray feathers in the nest.  Looks like the owls have been eating some pigeon.  And based on an owl pellet that Non Birding Bill near the nest, some other surprising species...but that's for future blog entry...

Owl Chick, Finally!

As I was working my way around my neighborhood the other day on my bike, I made one final stop before heading home to check on the great horned owl net.  I hoped that since it was so warm that the female would be up and out of the nest and maybe I'd get a glimpse of a chick.  She did seem to be up a little higher but I couldn't see any sign of the young.  I tried scanning the trees where I usually see the male perched as a sentry over the territory, but couldn't find him.  I decided to get an establishing shot of the nest.

That's when I noticed him--he was perched right out in the open above the nest!  Do you see where the nest is in relation to the male?  The nest is in the lower right hand corner in the crotch of the tree.  You can see her little tufts stick up out of the nest.

It was interesting to me that even though he was out in the open and I had my scope on him, a few people walked past me and didn't seem to notice.  Yo, people, huge owl up here.  As I took this photo, a Cooper's hawk flew in, circled the tree to buzz the owls and then continued on its way.  It didn't vocalize but it was as if the fly by was letting the owls know, "Yeah, I see you, you're not fooling me."

The male kept a hairy ball in the direction of the Cooper's hawk.  He never looked at me again after that, but watched the fast little hawk. A few other birds came in to mob them as well.

This flicker was my favorite.  She slowly worked the branches for food and then suddenly noticed the owl (that photo is right when she noticed the male) and started giving a warning call.  She even dove at the male a few times.  I wondered if she hadn't seen the nest because all the mobbing in the world by a flicker is not going to get that owl to move.  And let's face it flickers can't even drive out a starling.

The female wasn't too worried.  She seemed to be snoozing in the sun, paying no attention to me or the flicker.

I started to leave and I turned to take one last look and then I saw the female adjust herself.  I aimed the scope and up popped a baby owly head!  So cute and fluffy!  It shook its head a few times and then disappeared under the female again.  Nice to know that there's at least one chick in the nest.

Check out the baby, see the little white dot on the tip of its bill?  That's an egg tooth.  Something birds have in the egg that helps them chip out of the shell.  It usually sheds not long after hatching.  I checked over at Cornell's Birds of North America Online and looked up owl tooth development on great horned owls: "Young show remnants of yolk sac and retain egg tooth for 4–6 days (Turner and McClanahan 1981) or traces of both egg tooth and yolk sac for up to 2 weeks (Hoffmeister and Setzer 1947). Eyes remain closed until 9-11 days of age"

Young owls don't always hatch at the same time, there can be a day or two difference.  I wonder if this is the youngest owlet in the nest?  It's a safe bet that these birds are less than 9 days old or hatched early last week sometime.  Exciting!

Oh and I found this empty wrapper not too far from the nest tree.  I wonder what kind of shenanigans the owls witness at night?

 

 

 

Hidden Owl

Here's the male owl that's nesting near my apartment.  Look at how well those feathers blend with that bark. I've said it before and I'll say it again, "How many owls do I walk under in a year and never notice?  30?"

 

Uptown Great Horneds Still Around

The Crossley Birds and Beers was a blast. He was a fun interview and a blast after his talk--I think we closed the bar. If you would like to find out if Richard Crossley is coming to your town, check his site.

The great horneds near my home continue to incubate. It had been awhile since I took my scope and camera to the owls so I took them out yesterday. Even for a week day, several people passed beneath.  The keep an eye on the passers by but otherwise stay still.

Once again, the male was right over the main walkway. In this photo he's looking down  on a dad and his toddler son who had no idea they were walking right under a very large owl. This also leads me to wonder yet again--how many owls do I walk past on a regular basis.  I'm willing to bet that the number is very high.

What's An Uptown Owl Eating?

I mentioned earlier that there's a great horned owl pair nesting near my apartment in the Uptown area of Minneapolis. I love that we have such a large bird that is able to hide really well in such an urban area. Also, the distance that this owl is from my home, makes for a nice walk and a good incentive to get out and keep exercising in freezing weather so my biking muscles don't completely atrophy. I digiscoped this photo from the first day I saw the pair nesting, I don't always take my scope and camera.  One, walking through urban neighborhoods with that equipment makes home owners uneasy and can lead to police calls.  Two, I don't want to aim my scope every day at the owls and the nest to draw further attention and make them uneasy.

As I neared the area for the nest, I scanned the trees for the male. Some crows found him, they were cawing like crazy, but I didn't see him. When the crows saw me, the they took off. I got to point where I found an area in the snow covered in owl poop and pellets (I took the above photo with my phone since I didn't have my camera). Owls (like many predatory birds) cannot digest everything they eat and will regurgitate a pellet of fur and bones of what they couldn't digest from their prey. Owl pellets are fun to dissect because the bones give clues to what they've been eating. You generally do not find bones in hawk pellets because they tend to rip meat off of bones rather than swallow it whole and they have stronger digestive acids and the bones can break down.

Like Indiana Jones at an artifact, I carefully dislodged the large pellets from the snow. It suddenly occurred to me that where you see owl pellets and poop, the owl is generally overhead--at least, that's what I often tell people and have only found that to be true a couple of times.  I looked up and was so mad I didn't have my camera.  There was the male, directly over my head, about 20 feet up.  He stared down at me and was totally giving me the hairy eyeball...or would that be the feathery eyeball in a bird's case?  I quickly gathered the pellets and went on my way.  The owl never moved and is clearly accustomed to human activity.

Here are the pellets that I picked up.  I set a lime beside them to give an idea of size.  Two pellets were very dark and one was light gray.  I suspected right away that the pellet with the light gray fur was from a gray squirrel, since most of the mammal tracks in the snow around the nest are squirrel...and the female owl appears to be using an old squirrel nest for her nest.

The bones in these pellets are considerably larger than what you find from a pellet that you purchase.  Those are usually from zoos and wildlife rehab centers where the birds pretty much eat mice all day. This particular prey item was so large that the great horned owl couldn't swallow it hole and broke apart bones.  I think that's a rib bone up there and compared to the lime, that's a good size animal.

There were several pieces of vertebrae in the darker pellets.  I circled it in the above photo.  I puzzled over how to tell a rabbit spine from a squirrel spine.  I tried to crowd source that information on Twitter and got the following gems from the following Twitter users:

@ADruglis suggested: "Use a mass spectrometer to measure the ratio of calcium to disapproval in the bone."

Nice Disapproving Rabbits ref!

@ODN_Editor offered: "Any Easter egg shells mixed in? That's a dead giveaway."

Thanks.

@UppieSand said: "easy. Squirrels actually have them. Jk ;)"

Since Twitter was proving humorous rather than helpful, I went back to study the pellets.  I determined already that the lighter gray pellet was gray squirrel, I took to examining the fur of the dark pellet.

The fur was multicolored, dark, then brownish, then dark.  That was familiar...where have I seen that fur before?  Then it hit me: eastern cottontail.  I puzzled for a moment that it might be gray squirrel, the tail can have that color, but a raptor isn't really interested in eating squirrel tail.  It's mostly fur and bone--very little meat, why bother?

What was most interesting to me about all three pellets was that there were no small mammal remains in there, no mice, no voles, it was all big stuff.  I'll be curious to see if we can find other prey items in future pellets.  In the meantime, Uptown rabbits and squirrels, beware.

 

Great Horned Owl Nest In My Hood

I debated about whether or not to blog this, it's an owl nest and some people can get their undies in a bunch when someone talks about them publicly. Some birds seem to attain a cult status and people get particularly prickly about them. Owls are definitely a cult status bird, even garnering their own set of fan boys and fan girls (and owls are cool, I can see why).

I have a great horned owl nesting within walking distance from my home. I have mixed feelings about blogging it. On the one hand, I get the wisdom of keeping nests on the down lo. On the other hand, I live in a very urban area and these birds have chosen to nest in a particularly high traffic spot. I think they knew what they were getting into. There are all sorts of people well aware of the nest and happy to walk up to any stranger and say, "Hey, there's owl right there!"

I'm not going to reveal the exact location, but that still won't stop some complainers. Last winter, a birding organization received an email asking that something be done about me because I had revealed a northern hawk owl perching location in my blog, it wasn't even nesting. I thought it was funny that an organization that I'm not associated with got such an email (what are they gonna do, fire me). It's no secret you can find northern hawk owls at Sax Zim Bog and I had gotten the location from a website promoting where to find the owls.  Ah well, haters gotta hate, as the young kids say these days.

Here's the male keeping watch near the nest, even though it looks like his eyes are closed, those little slits are open and he's keeping an eye on me with my scope.

So, what should you do if you find an owl nest? I think keeping the exact location hidden from the local birding listservs, Twitter, Facebook and FourSquare is a good idea.  But when you find something so cool, there can be a huge temptation to share it.  Be cautious with how many people you tell.   Locations should be shared to some groups--say for instance a place like The Raptor Center. If orphaned great horned owl chicks end up in their clinic, they try to find surrogate nests for the chicks. You could also submit it to Nestwatch a website trying to document bird nesting throughout the US. If someone is keeping track of breeding birds for an overall study or atlas, that would be a good idea too.  These could be safe ways of documenting the nesting process, a fun project for you, but won't bring hoards of people to the nest site.

I'm sure I'll be walking by and checking these birds out throughout the spring. I have an idea of when incubation started so hopefully some owl chick photos will come along.  I'll be curious to note the number of people, especially those walking their dogs who will walk past it without realizing it's there.

I'll also be curious to see how the nest holds up.  Great horned owls do not build a nest, but take over old hawk, crow or squirrel nests.  I'm pretty sure that meatball of leaves the female owl is hunkered on is an old squirrel nest. She had lots of squirrel nests to choose from, some more secluded than others. It's interesting she chose one in a well traveled. Here's hoping that this turns out to be a big win for urban great horned owl nesting this spring.

 

Unexpected Afternoon Owls

I am terrible with people names--bird names are generally not a problem.  However, if I've met someone at a bird festival in Texas and see in them in winter in Minnesota, I have a tough time remembering them.  Same with meeting one of Non Birding Bill's friends at the grocery store--totally clueless.  Sometimes that happens with birds too.

Saturday, NBB and I met up with some friends who live along the St. Croix River and were gracious enough to take us out on their boat.  It was the perfect low key way to spend the summer day.  What was especially fun for me was cruising through this area for fun, not work.  I've been on this stretch when we've banded bald eagles and as we coasted along, I recognized nests.

The area was chock full of herons, egrets and osprey--we even had fly by of a family group of sandhill cranes.  Above is a great blue heron perched on top of a snag.  We marveled at how peaceful an area so close to the Twin Cities can be.  The back waters were still with lush patches of arrowhead and cottonwoods.  Green frogs sounding like a bunch of musicians trying in vain to tune up for a 21 banjo salute called from the vegetation.  Taking in all the sounds of summer, I heard a familiar screech. I knew instantly that the screech sound was a raptor...but what kind...the little hamster wheel in my head churned...I'd heard it before...but where...it was a begging call...it was daytime...but I knew it wasn't a hawk...owl...it was an owl...daytime...late afternoon and time of year could be barred owl...but barred owl doesn't sound like that...it sounded...like...a great horned owl.

Our friends eased their boat into a small channel and one owl flushed but then we found another perched on the side of the tree--it was a total great horned owl (all the way).  Since we were in a pontoon boat, I thought I would give digiscoping the owl a try.

Getting the great horned owl in the scope was a challenge because any slight movement on the boat moved the scope view and then the darned bird was looking way.  As I lined up my camera, I whispered to Non Birding Bill to sound like an injured mouse.  He helpfully said in a less than enthused manner, "Ow."

But that did the trick and the owl turned to look at us.  There are plenty of times when I suspect an owl is nearby or I can hear a sound and know what bird is there, but I don't always get the opportunity to show friends that what I saw is actually there in the trees.

There were at least three different owls in the area based on the screeching calls and the directions the vocalizations came from.  Great horned owls make several sounds besides the expected hooting.  They screech, they twitter, they bark, heck, they even snap and hiss.  I realized that the screech I heard was the same sound  I have heard imprinted great horned owls give at The Raptor Center when they beg for food--I generally don't hear it in the wild, especially in the afternoon.  I thought it odd that great horneds would have begging chicks right now, that seems late for Minnesota.  But if there first nest failed, the adults could have tried a second clutch.

I thought this was interesting too because we were near one of the bald eagle nests that in 2009 was used by great horned owls.  I wondered if the parents of this group of owls had been the ones to use the eagle nest last year?

Always appreciate an unexpected owl.