Karla Bloem http://www.internationalowlcenter.org Sat, 24 Jun 2017 05:27:21 -0500 Krumkake en-gb Owl Ears http://www.internationalowlcenter.org/blog/item/20-owlears http://www.internationalowlcenter.org/blog/item/20-owlears

There are so many things you have probably learned about owls over the years:

Owls are nocturnal.

Owls fly silently.

Owls can turn their heads 270 degrees.

Owls mate for life.

Owls have asymmetrical ears.

None of these statements is true for all owl species, but it is very difficult to find out the details about each statement. That's why our staff likes to go right to the source when we can't find original literature. That means we use owls that have been found dead for various reasons so that we can learn more about owls first-hand. (N.B. We have state and federal permits to allow us to pick up and use dead specimens.)

In June we had a staff development day in which we dissected four owl species: Great Horned Owl, Barred Owl, Eastern Screech-Owl, and Long-eared Owl. One of the things we specifically wanted to compare between the species was their ears.

We knew from skulls in our collection that Northern Saw-whet Owls have one ear higher than the other. Their ears are so asymmetrical  that the skull is actually asymmetrical. But our other skulls (Barn Owl, Great Horned Owl, and Great Gray Owl) didn't show the same obvious asymmetry. 

Before we cut open our owl specimens we investigated the ears. How big were they? Could we see that one ear was noticeably different than the other ear? We saw extreme differences.


Eastern Screech Owl Ear small

The Eastern Screech-Owl's ear is large compared to many bird ears, but not compared to other owls. The bluish thing visible inside the ear is actually the owl's eyeball. Yes, the eyeball. Owls' eyes are gigantic in relation to their skulls, with their brains being about the size of one of their eyes. This owl did not seem to have one ear higher than the other.

Great Horned Owl Ear small

Great Horned Owl ears are bigger than Eastern Screech-Owl ears in actual size, but probably not in proportion to the size of their heads. Again you can see the side of the eyeball in the ear opening. Their external ears appear to be placed at about the same level on the sides of their heads.

Barred Owl Ear small

Barred Owl ears take up a good part of the side of their face. Unlike the Great Horned Owl and Eastern Screech-Owl, the Barred Owl has a flap of skin that covers their ear opening. Great for blocking out sounds you don't want to hear, and perhaps to aid in funneling sound into their ears. They use hearing more in their hunting than Great Horneds and Screech-Owls, and seemed to have some asymmetry in their ear openings.

Long eared Owl Ear small

The Long-eared Owl ears were EXTREME compared to the other owls. The ear slit in the side of its head starts down near its jaw and goes almost to the top of its head, on both sides. There doesn't seem to be much skin that holds their faces together! The blue in the photo is the eyeball, and the rest shows the skull and how the ear opening inserts into the skull. The ear openings are CLEARLY different from each other, with one inserting lower into the skull and the other higher. The also have a long, thin flap of skin, edged with feathers, that can cover the entire opening.

We saved the skulls and eye bones and are currently cleaning them to add to our collection. (Yes, bird eyes have bones in them, and they are large in owls.)

We also looked at oil glands, stomach contents, feather attachments, range of head movement possible, and more. Some of it is a bit gory, so we'll spare you the images. But if you're interested in this kind of thing, check to see when we plan to hold our next Owlology 401 class, where you get to see an owl dissection first hand in a small group setting.

As we get specimens of other species we'll take more pictures to compare, but as you can see, owl ears are not all created equal!


karla@internationalowlcenter.org (Karla Bloem) Blog Fri, 05 Aug 2016 15:41:02 -0500
How Far Can an Owl Turn Its Head? The In-Depth Answer. http://www.internationalowlcenter.org/blog/item/19-howfarcananowlturnitshead http://www.internationalowlcenter.org/blog/item/19-howfarcananowlturnitshead


Can an owl turn its head all the way around? The answer can be yes or no, depending on the starting point of the head, so some clarification is required.

If the starting point of the head is facing straight forward, then no, they cannot turn their heads all the way around. If YOU start out facing forward and turn your head as far to the side as your head will go, most people can turn their heads about 90 degrees. An owl, however, can start out facing forward, turn its bill over its shoulder, keep going until its bill is over its spine, then keep going until the bill reaches the other shoulder...a whopping 270 degrees from the front!

That being said, you will almost never see an owl turn its head more than 180 degrees from the front. They almost always stop when their bill is over their spine and rotate their head around to the other side to continue watching something if necessary. 

Now if your starting point for this whole head-turning discussion is with an owl's head over its spine, it can easily turn its head back the way it came from to the front, then all the way to the spine in the other direction, making for a nice easy 360, something they do regularly. So if your starting point is to the rear, then yes an owl can turn its head all the way around.

Now to get the idea of the absolute extremes of which an owl is capable, if an owl starts with its head at the maxium twist of 270 degrees (from the front), then goes back to the front and does a maximum rotation in the other direction, the full range of motion is a whopping 540 degrees! (Never mind that you'll probably never see an owl do more than the 360 described in the previous paragrah.) A human's maximum range of rotation from side to side is more like a measly 180 degrees.

Here's a rare video of an owl acutally rotating its head a full 270 degrees from the front.


Below is a video that shows the adaptations owls have to allow them to turn their heads so far. (Note that the video of owl head-turning in this video doesn't show an owl turning its head 270 from the front--even the video makers didn't grasp the concept of what it means for an owl to turn its head 270 degrees from the front!)


So now you know the whole answer....


karla@internationalowlcenter.org (Karla Bloem) Blog Sun, 16 Aug 2015 10:34:54 -0500
Owl Updates http://www.internationalowlcenter.org/blog/item/18-owlupdates http://www.internationalowlcenter.org/blog/item/18-owlupdates

I always say that you learn a lot about cars if you have one that doesn't run very well. The same can be said about owl health: you learn a lot when they aren't healthy.

Rusty the Great Horned Owl is still slowly healing. After six weeks in a dog carrier, however, he had had enough. When I took him out so Hein could clean the carrier and put down a fresh astroturf mat, Rusty wriggled through my arms and out in the breeding pen. In a way it was a good thing so we could see how well HE could see. I was absolutely elated to see him fly up to a perch!! While his vision certainly isn't perfect, he can fly from perch to perch, which is FANTASTIC! He has more trouble seeing when it is very, very dark, and I have to catch him in a net to treat him now, but now he can be free and we can observe him on the live cameras again. We did close the door to the flight pen, however, so he and Iris are separated. This allows us to continue to give Rusty medicated food.

Click here to see Rusty's jail break video.

A recent checkup showed the Rusty's corneal ulcer had only healed a small amount in the past month. The medication on his food, however, hinders the healing of the ulcer so we are reducing that medication in hopes his ulcer will heal on its own. Otherwise he needs to be anesthesia and a minor surgery to help it heal. An ultrasound of his eye revealed the "gunk" in the lower portion of the back of his eye and a slight cataract in his lens. Keep heling, Rusty!

Uhu the Eurasian Eagle Owl is still undergoing treatment for her blepharitis. A culture revealed that it was being caused by a bacteria that causes pink eye in cattle, so theoretically a fly transmitted it from a cow to Uhu. (How, we're not sure, since are owls are in screened aviaries and only a random fly follows us humans in.) At any rate, we have a specially compounded ointment to apply to her eye four times per day. Her eye is responding slowly but surely, and she will begin work when it is healed.


Mitzy the fledgling Tawny Owl was an absolute puzzle. After 10 days of the top vets at the University of Minnesota Raptor Center working with her, they simply could not figure out why her kidneys or intestines were not working. After much discussion with many people, with very heavy hearts we made the decision to let her go. The gross necropsy did not give any good answers, other than we already knew her kidneys were grossly enlarged and she had no intestinal blockage. The microscopic necropsy is only partially completed and may or may not yield answers. Rest in peace, dear little Mitzy.



karla@internationalowlcenter.org (Karla Bloem) Blog Sat, 08 Aug 2015 11:59:23 -0500
Emergency Medical Care for our Owls http://www.internationalowlcenter.org/blog/item/17-emergencymedicalcareforourowls http://www.internationalowlcenter.org/blog/item/17-emergencymedicalcareforourowls

I was a basket case, nearly hysterical, in the wee hours of Sunday, July 5. Mitzy, the 8 week-old Tawny Owl that we had just gotten a week before, was completely refusing to eat. She wouldn't eat tibits, she wouldn't eat chunks, it didn't matter what kind of meat was offered, and she now reversed gears and upchucked anything we tried to force feed her. Even a liquid slurry of meat baby food and gatorade came squirting out of both ends. Her weight was dangerously low. She needed medical care immediately.


As if that wasn't bad enough, Uhu, the big female Eurasian Eagle Owl we acquired in late May, had started holding her right eye shut on Friday. Sometimes birds will have minor scratches on their eyes that will heal on their own in a few days. But this was obviously worsening, her eyelid was terribly swollen, and now she was just sitting on the ground, not going up to her perches. She ALSO needed medical care right away.


This was all on top of Rusty, the male of our breeding pair that are streamed live 24/7 on our website, was five weeks into the recovery from his own eye injury sustained when he flew straight into a post from 30 feet away when I was cleaning the fligth pen. At first I thought he would be fine, since he showed no effects the first day and only very minor issues the next few days. But when he flew to the nest platform and refused to leave, and we could see blood filling his eye with the cameras, he needed to go in.


In hindsight I should have brought Rusty in for medical care immediately, instead of waiting to verify that he was having serious issues. Because we waited so long the damage to his eye was severe. For a bird who only has one eye, this was a very, very, very grave issue.

Rusty has been confined to a dog carrier in the breeding pen so we can put drops into his eye twice a day as well as give him medication in his food. We keep his carrier in the breeding pen so he and his mate Iris can still hoot together, which they do every day. I knew he was starting to see, and he was due for a checkup on Tuesday or Wednesday, but if we had to drive 2.5 hours to go to The Raptor Center for the other two, I was hoping that it would be OK to bring Rusty along too (even if it was a Sunday.)

Mercifully my call on a Sunday, the day after the 4th of July, was answered immediately, and I was told I could bring all of the birds in...I just needed to get there ASAP. I dropped everything, told the staff where I was running off to, caught Hein, loaded birds, and we were on the road.

I need to mention here that I had only finished making Uhu's travel box on Thursday, so it was only JUST ready, thank goodness. And fitting her carrier along with Rusty's travel box and Mitzy's pet carrier (she likes to see out) was absolutely all that my 2-door Chevy Tracker could accomodate in addition to myself and Hein. It's plainly obvious that the Owl Center needs a van ASAP so we can transport all of our birds to and from work and for trips like this. (Please contact us if you or someone you know may be interested in donating a white or a black van with removable seats and air condinitioning that's in very good condition!)

At any rate, The Raptor Center was busy with patients, so we had to wait a bit before being seen. I was happy to see Dr. Galan was staffing today, as she was the doctor who had been working with Rusty already. Thankfully her assistant was working too, as normally she doesn't have an assistant on Sundays.

Mitzy, the most critical, was first. The poor girl had to be handled more like a wild raptor than a fledgling used to being around people and never being restrained. But it was necessary for the exam and X-rays. She was dehydrated, probably from not eating much at all, but otherwise her physical exam was good. Her X-rays showed slightly enlarged kidneys due to the dehydration, and her intestines were just a big white blob...difficult to tell if she might have a partial obstruction that would cause her to throw everything up. Barium X-rays might be necessary to figure out what's going on.

They gave her subcutaneous fluids to hydrate her and oral antibiotics, anti-inflammatories, something to make her intestines move, and clear fluids. Thankfully that all stayed down and she did poop before we were done with the other owls. Currently all the top doctors at The Raptor Center are consulting to best help Mitzy. She will stay there, under their expert care, in a "private" cage (for "owned" birds, separate from wild birds) until she is eating properly.

Uhu was up next. When Dr. Galan and her assistant came out of the room where they had extracted her from her box so they could properly restrain her, they said "She's VISCIOUS!" She's also huge--she makes Great Horned Owls look small.

I was shocked to hear Uhu's weight was only 2030g (4.5 lbs). Ruby even weighs a bit more than her! But Ruby is in great physical condition and might be a bit on the chunky side...and Uhu has never been able to fly before, so her breast muscles are atrophied and they are a large part of her weight. Although she can fly in her 8' x 20' aviary, we need to find ways to help her build up her flying muscles. The rest of her physical exam was fine, other than her right eye.

Her right eyelid was very swollen, and probably very painful (blepharitis). She also had a small corneal ulcer. This would have resulted from some irritation to the eye, scratch or abraison. We don't know what happened, since we do not yet have security cameras in the new aviaries. This brings to the forefront our need for cameras in those aviaries so we know what happens when we aren't there, and so we could correct anything that may have caused Uhu to injure herself, if indeed it was a tiny problem with the aviary itself.

At any rate, Uhu now needs ointment put into her eye daily, and will receive an anti-inflammatory with her food every night. I have to say the thought of putting ointment into the eye of an owl this big who I had not had on the fist before that day was pretty daunting.

Finally it was Rusty's turn. I was hopeful for his eye since he had obviously begun to see some. He could track my hand when I reached in to put his food in his carrier at night, but I didn't know how well he was seeing. His iris was its normal yellow color again, but some scar tissue at the bottom touched his pupil, so when it contracts his pupil is more oval instead of round. This isn't a problem.

Although his retina is still inflamed, the top portion is clear (yea!!!!!!). The lower portion was not visible due to more gunk from his injury that just needs to be reabsorbed. This will take quite a bit of time. Dr. Galan was ready to give the OK to try putting him into a small avairy with a camera so we could observe him to see how well he could find perches and get around, but she found an ulcer on his cornea. We now need to switch from giving him eye drops twice a day to putting ointment in his eye three times a day. Yikes! His one remaining eye is just so important to him that we can't risk it. He's due for a recheck on Thursday.

Needless to say that I was exhausted, relieved and thankful when we arrived home just before 9 PM.

The silver lining in all of this is that I am now forced to work with Uhu. Whenever I approached with a glove before she would hiss and lunge at it with lightening speed, so I was going too slowly. Now that I HAVE to handle her, I found out that the hiss and lunge was a big bluff, and that once on the glove she LOVES to have me walk around so she can look at things. So to treat her eye this morning, I got her onto the glove, walked outside, and just squirted the ointment into her eye as she stood on my fist. I think she's going to be a really good education bird, and will start coming to work as soon as her eye is well, assuming she does well at work too.


If you'd like to help with medical expense for Rusty, Mitzy and Uhu, or donate toward other necessities like a security cameras for our new aviaries or a wrap job for the van that we hope someone will donate, click here.

If you'd like to send a check (this is especially good for larger donations, since all online donations incur processing expenses), please make it payable and mail to:


International Owl Center

PO Box 536

Houston, MN 55943


We have not received any medical bills yet for Rusty's three visits, Alice, Uhu, and Mitzy's visits, or for their medications, but it will certainly be well over $1,000. We anticipate costs to install security cameras in the new aviaries that integrate with our current system that monitors the breeding and release training pens will cost around $3,000 - $4,000. An awesome full wrap-job on a white or a black van will run around $4,000, and we'll have a fantastic "Owlmobile"!

Thanks for your support!

karla@internationalowlcenter.org (Karla Bloem) Blog Mon, 06 Jul 2015 10:25:24 -0500
Plans for 2015 http://www.internationalowlcenter.org/blog/item/16-plansfor2015 http://www.internationalowlcenter.org/blog/item/16-plansfor2015

Two nights ago I formally announced the plans for 2015. It is a big change with a lot of thought that went into the decision, so this chat dialogue explains it all. For many reasons listed below we will not be raising owlets in 2015, but will still collect data. The goal is to focus efforts on opening the International Owl Center to the public and starting to publish some research findings. 


Karlaowl : I'm pretty sure I heard a Saw-whet Owl tooting when I was feeding the kids tonight.

So of course I can't just barf up the news straight...I have to work into it.

Let's go backwards a bit. This whole project started because of Alice the Great Horned Owl, my co-worker with whom I do educational programs. She was injured when she fell out of her nest at 3 weeks of age and will always be unable to fly.She works with me doing educational programs, but because she was injured so young, she imprinted on humans.

She thinks she's one of us, although she still has all the normal owl instincts and she expects me to act like a male Great Horned Owl.No one has written a book on how to be a male GHO, so I was kind of clueless. Alice obviously got frustrated with me sometimes when I didn't respond properly to her behaviors and vocalizations. I figured I'd go to the scientific literature and look up GHO vocalizations. I was extremely surprised to find out that no one had ever studied GHO vocalizations. David Johnson, Director of the Global Owl Project, encouraged me to begin that study. I was in a unique position with Alice, and of course the wild owls came around the yard too because they could hear Alice.That study started in the fall of 2004. I recorded Alice's vocalizations and noted the behavioral context of each. I also recorded the wild owls.  I couldn't see what on earth the wild owls were doing, and I rarely knew the behavioral context.

I only could record the sounds they made, and they made some weird sounds! I realized I could identify each owl by their territorial hoot, because each was slightly different.  When you've heard literally millions of hoots from one bird, it's really easy to hear what's different about another owl's hoot.

greatful2: did you stay at home all during this time for the study, or just nites?

karlaowl: I slept with a recorder on my nightstand, and just recorded when the owls woke me up.

I was working days at the Nature Center. I knew I needed to do recordings at nests, but out here in the country the owls wouldn't let me get anywhere near a nest before they'd fly away. There was a nest in Rochester, MN on a golf course where the owls were totally habituated to people,so I spent a few nights in a sleeping bag on a posh golf course, recording owls when they woke me up.It was COLD.I got what I could, but realized I wouldn't be able to record the quiet sounds of the babies without a mike in the nest.  I simply couldn't record the courtship stuff since that didn't necessarily happen at the nest and GHOs often only use a nest one or two years because they fall apart after that time.You never know where they will nest. It's not like I could put up a nest box with a cam and mike in it and go from there.We knew that owlets do not have adult sounding hoots when they leave the nest.So for all of these reasons, I realized I would have to breed GHOs in captivity to find out these things.It took much discussion with the MN DNR and US Fish & Wildlife Service, but they granted those permits to me in 2007. For multiple reasons, my aviaries didn't get built until 2010, which is when Rusty and Iris moved in.Scarlett Owl Hara showed up that first winter and harassed them like crazy, apparently wanting Rusty for her mate (and wanting to kill Alice)   No breeding in 2011, but 2012 we got eggs that didn't hatch.

JudyRameior  Sad time, March 2012

Karlaowl: 2013 gave us the 3 P's, Pandora, Patrick, and Patience. They were reared as wild birds by their parents with minimal human contact. They were trained on live rats and released to the wild from the flight pen in November 2013.They were each wearing a transmitter on their tail so we could track them (thanks to Bob Anderson and Amy Ries for getting them put on!) We lost Pandora's signal after 5 days. Patrick's stopped moving on the bluff behind our house after a month and we found his transmitter, still attached to his tail feathers which weren't attached to him, on the ground. He either bit his tail feathers to lose the transmitter or the attachment created a weak point that caused the feathers to break. Patience we tracked until she naturally molted her tail feathers in May 2014. The 3 P's taught us that owlets can do "proper" hoots, albeit in their tiny little voices, at just over 2 weeks of age. Then they went through the teenage "voice changing" phase and sounded like a rubber duck trying to imitate and owl at 5 months of age. Around 7 months of age they sounded like adults. But would owlets reared by humans have the same vocal development? Enter Ruby and Rupert in March 2014. We took them away from Rusty and Iris when they were 2 weeks old. We felt yucky for doing it, but Ruby and Rupert were happy little owlets and readily adapted to being with people. Being raised by humans would mean that they would not be able to be released to the wild. I was rearing them to be education birds, which meant they should get lots of human attention. So they came to live in the house with us. I very quickly realized that raising owlets for a vocal study and raising owlets as educational birds have two different sets of needs. For the vocal study I needed them on live cams, with audio, 24/7 so people could help with observations and every part of their development could be recorded. But having owlets in the house with lots of human contact and having live streaming video/audio at the same time, well, that didn't work so well. We simply couldn't stream the audio for privacy reasons and without getting a new expensive cam with night vision, you couldn't even see them at night. Not good for the vocal study, but it's what we had to do since we were committed to rearing them as education birds this year. I could, however, do playback of owl vocalizations with them to see how they responded, that was helpful but I think we missed a lot, and they didn't have the same natural stimulations that parent-reared owlets do. Owls don't call just to hear themselves call. They are communicating, either sending a message or responding to a message.

Peggyrausch: did they respond to recordings?

Karlaowl: Without certain stimuli, they wouldn't vocalize. They did, Peggy, respond to some of the recordings. Playing Iris' feeding calls REALLY got them excited to eat when they were little. But with Ruby and Rupert as education birds, we'll be able to look at their vocalizations for their whole lifetimes. One question is if their territorial hoots will sound the same their whole lives. We have them recorded starting around 2 weeks. Initially I thought I would keep Rupert and place Ruby elsewhere once they got their adult hoots. Now however, I think it's best to keep them both, so I can look at one male and one female over their lifetimes.

JudyRameior: YAY!!!

Karlaowl: Plus they love/hate each other just like siblings. So right now I'm in the process of moving them onto my education permits. They'll take over the GHO education part of the program when Alice goes on maternity leave, which starts in January.  Alice, Ruby, and Rupert can share the workload throughout the year.

Sammyloufalany: so they will soon be off cam?

Peggyrausch: it will really be interesting to hear how their voices change

Karlaowl: Ruby and Rupert will move into the new aviaries when they are complete. I will get new security cameras for the new aviaries, but I'm not sure how the new cams will mesh with our existing cams and streaming. I hope to still be able to stream them, at least sometimes. So this fall I have had to start planning for the 2015 season.

maxi23: What about streaming Timber sometimes?

Karlaowl: I was working on a new research proposal, reviewing the literature, etc. Timber's cam is a "cab cam", so not really streamable without some major work. Plus the audio is terrible and the video gets lots of interference since it's wireless. As I was working on the plans, figuring out what I needed to do next, I realized that I was REALLY feeling time pressure right now. It's time to dive into Owl Festival planning, and I'm working really, really hard to get the Owl Center open before the Owl Festival.

greatful2: Karla do you have to come up a new study each year? so that you can continue to keep I&R?

karlaowl: I'm fundraising, handling money, working on interpretive displays (or should be), getting the building ready to go, trying to figure out how to hire staff because I REALLY need to. I do have to do a new research proposal each year, yes and I realized that I seriously have to start watching my time commitments better.

Peggyrausch: sounds like you're stretched pretty thin.

Karlaowl: I also realized in the literature searches that there are several things that I could publish now and part of my permits is that I need to publish in peer-reviewed journals. In the world of science, if it isn't published, it didn't happen. I kind of sat with all of these thoughts a few days until I finally came to a conclusion that felt right for me for this year. I decided that I need to take 2015 to get the Owl Center up and running as well as analyze data and submit some things for publication. I need to take this year off from raising owlets. I know many of you will be disappointed, but I realized that I have to watch out for my own health and well-being, and I was really, really pushing it as it is.

Tampabayrabbit: couldn't rusty and iris raise them on their own?

Karlaowl: Tampa, there still has to be research proposals, data has to be gathered and reviewed, etc. I can't just let them breed without the research part.

JudyRameior: Burnout not recommended!

Karlaowl: Yes Judy, and I'm too close to burnout. Thankfully I realized it before it was too late and I made a mess of things.

iamsoon2b: so, where does this leave R&I?

karlaowl: I will let Rusty and Iris do their thing as usual. I will let them lay eggs, but once the clutch is complete I'll remove the eggs and replace them with fake eggs.

JudyRameior: Oh, kinda Alice-ish?

Karlaowl: So we'll be able to see how long Iris will sit before she abandons (which isn't fun, but it's important data). Yes, Judy, except Alice gets to sit on her own (infertile) eggs. So in the literature searches I found there are some research priorities that are REALLY simple to get data on here online.Believe it or not, some of the research priorities, from 16 years ago as well as the updated Birds of North America account this year are: The length of time the female is off the eggs; The time of day of egg laying; If eggshells are removed, eaten, or trampled; Hatching intervals between owlets. All of you can easily help gather that data, and it won't take my time to review your notes. Also, rose and jonnetje are taking fantastic notes every night, throughout the whole night, on behaviors and vocalizations. After they finish up doing this for a year (which I think will be this spring?), then we can analyze their data to look at hooting behavior throughout the year. This was another research priority, and has big implications for all the citizen science owl surveys that use passive listening.They need to know when to have their volunteers do surveys to get the best results. What time of year do they hoot most? What weather conditions are best? Etc. Since rose and jonnetje have put so much time into this (essentially a full-time job), I will list them as co-authors on that paper.

Greatful: just a ?? Karla, can they be incubated without Iris' help? just curious

Peggyrausch: so what happens to the real eggs

Tampabayrabbt: could you have a volunteer person that needs the credits to do the research and information on the owlets instead of yourself?

Karlaowl: So back to some questions. I can't really have a volunteer come in and do my part of the research since it requires really, really extensive experience in this project, and it has to be done in our house (the video/audio analysis). I have reviewed my decision for 2015 with the permit authorities, and as a result do not have permission to raise owlets in 2015. So we can't incubate the eggs. Plus what would we do with them? I mean what would we do with incubator-hatched owlets? I don't want to be in the business of raising lots of owlets only as education birds

Maxi23: Could some sanctuary or other place foster the eggs? I mean an owl at another sanctuary, etc.

Karlaow: If the eggs are raised by anyone else, the result would be the same: they would be education birds. I would suspect no one is interested in doing that.They wouldn't have authorization to release them to the wild.

Birder23: so they couldn't be trained with minimal human contact & let free (more expense & would have to get another)

Karlaowl: No, birder, the release to the wild is a very special permission that is almost never granted. There are a LOT of laws that pertain to birds, what kinds of permits there are, and what you can and can't do.

JudyRameior: So the 3 Ps were more special than we realized!

Peggyrausch: It sounds like rusty and iris might need to be placed somewhere

Karlaowl: Rusty and Iris are allowed to stay here this year. They are actually being put on my education permit. Normally education permits are only for birds used on the fist in programs or in display aviaries where people can see them. Rusty & Iris would NOT be OK with either, but the DNR determined there is educational value on our website that relates to streaming them online.

Paula2473: sad that its so complicated to take the eggs and just let another owl have them to raise×

Karlaowl: Paula, the permit stuff is really complicated for me because I'm doing something that's really "not normal" and requires a LOT of discussion of all the permit folks and supervisors. I would like to allow R & I to lay eggs, since that what their hormones are telling them to do. Plus we can still get data on time of day of egg laying, time off the nest, etc.

JudyRameior: They will just think eggs weren't viable. Happens in nature.

Tampabayrabbit: what about the outside owls, couldn't they take care of the eggs that are laid??

Karlaowl: Tampa, I would again need special permission to mess around in a wild owl nest.

Paula2473: so where are the kidz going? does it remain the same?

Karlaowl: Ruby and Rupert will stay put until we finish the new aviaries, then they'll move in there (on the back side of our garage). I'll try to stream Ruby and Rupert still, but we'll see what magic I can work with integrating new technology of a different type.

Tampabayrabbit: so in 2016 then will rusty and iris raise their eggs again?

Karlaowl: Tampa, I will have to do a new research proposal for 2016 and get permission. Actually what I want to do next is to have R & I rear some foster kids, unrelated to them, to see if they sound less like R & I than their own kids, looking for inheritance of hoot characteristics. Having foster owlets is not as easy as I would like it to be. To just get owlets from a rehabber I would technically need to be a master class rehabber, which takes 8 years of working with other species. That was part of my decision too: this is going to be complicated to figure out how to get unrelated owlets for them.

Maxi23: Would Marge Gibson have time to help?

Karlaowl: Marge would help, but we're in different states with different laws. If she were in MN it would be much more doable. She could designate me as an out shelter and no problem.Just to go to WI with my owls (which were hatch in WI, by the way), we have to get health certificates from a vet, a temporary wildlife exhibition permit from the WI DNR, and a circus, rodeo and menagerie permit from the WI Dept of Ag. Not kidding! The laws are there for good reason. And it's impossible to predict every situation that will arise.

Tampabayrabbit: but patience went there on her own with no permits lol!!!

Karlaowl: I know tampa, I thought it was awesome that Patience went to WI with no permits! Ha!

Donnadolittle: It's likely Ruby and Rupert will mate and lay eggs. What's your plan then?

Karlaowl: If Ruby and Rupert lay eggs I will replace them with fake eggs. I don't want inbreeding, but I do want Ruby and Rupert to be comfortable, and I think their companionship is good for them.

Tampabayrabbit: Karla when rusty and alice hoot at each other do you think its territorial or are they talking with each other???

Karlaowl: I think Alice is mostly hooting for attention from me, but Rusty hears it and has to hoot back to advertise his territory. At least that's my take on it.There are some rehabbers that swear by "companion birds", that each bird should be house with another of the same species or another compatible one. Sometimes a bird does dramatically better in captivity if housed with a "pal"

Tampabayrabbit: Karla will you be getting any more owls down the road?

Karlaowl: Yes, tampa, I will get more education birds for the Owl Center.

Maxi23: I assume at some point you'll get a barn owl?

Karlaowl: Yes, Barnies will be on the docket at some point in time. Probably from a breeder, since my understanding is that unless they come into captivity very young they usually don't adapt to captivity well. Great Grays would be tough, since they usually don't adapt to captivity as an ed bird unless they come in very young.If you cam watchers read the Birds of North America account on Great Horned Owls, you will realize that you know more than what is in the published literature about the intricacies of breeding and vocalizations.Thank you all for being understanding about 2015. I know this isn't what you wanted to hear, but I needed to explain what went into the decision so it would be easier to accept.OK, so to summarize, this is the information you all can help to gather from this site AND FROM OTHER GHO SITES:

Time of day of egg laying (watch our youtube video of egg laying to see what it looks like)

Time between eggs being laid (to the hour)

Time between owlets hatching (to the hour)

What happens to the eggshells after hatching

How often and how long the female is off the nest during incubation (like a daily log of leave the nest, return to the nest times)

And at OKC (or any other site where the mike is very close and good enough) VERY ESPECIALLY any hoots by owlets

So the more cams we can get data from, the better.It's best to ask permission, so I'll talk to Jeff Click.Let me know who else I should get in touch with to use data from their cams.

JudyRameior: How to report, Karla? Obs form here? e-mail?

Karlaowl: The observation form would be good, but I'll need to modify it.

karla@internationalowlcenter.org (Karla Bloem) Blog Fri, 19 Dec 2014 15:38:02 -0600
Ruby Makes Alarm Calls at 9 Weeks http://www.internationalowlcenter.org/blog/item/15-rubyalarmcalls http://www.internationalowlcenter.org/blog/item/15-rubyalarmcalls

Adult females have a reputation for making a "wac-wac" call when alarmed around the nest (a type of double squawk that is also described as "barking.")  We only observed it a precious few times last year in the owlets, and honestly, the first time I heard it I was certain it was something other than an owl.  I had no idea an owlet could or would make this vocalization.

Ruby made the same call today at about 12:40 PM, so we have good color video of her doing it.  Perhaps the owlets make more different types of vocalizations when there aren't adults around to make them instead.


karla@internationalowlcenter.org (Karla Bloem) Blog Sun, 11 May 2014 13:27:04 -0500
Ruby Hoots at Rhett http://www.internationalowlcenter.org/blog/item/14-rubyhootsatrhett http://www.internationalowlcenter.org/blog/item/14-rubyhootsatrhett

Last night Victor, the wild bachelor male to the east of us, paid a visit.  Later Rhett, the mated resident male paid a visit.

The owlets did begging calls, but when Rhett got close enough for them to see him, the owlets switched to bill clacking and Ruby hooted several times!


karla@internationalowlcenter.org (Karla Bloem) Blog Sat, 10 May 2014 07:21:21 -0500
Owlets move to flight pen and begin training http://www.internationalowlcenter.org/blog/item/13-owletsmovetoflightpenandbegintraining http://www.internationalowlcenter.org/blog/item/13-owletsmovetoflightpenandbegintraining




karla@internationalowlcenter.org (Karla Bloem) Blog Mon, 28 Apr 2014 15:05:44 -0500
Moving the Owlets Inside http://www.internationalowlcenter.org/blog/item/12-movingtheowletsinside http://www.internationalowlcenter.org/blog/item/12-movingtheowletsinside

Today it was time to band the owlets with closed bands to show they were raised in captivity.  It was also the time to move them inside so they will be well socialized with humans so they will be comfortable in their future lives as educational ambassadors for their species.

Removing the owlets from the aviaries went well...Iris didn't try to attack.  I do have to say they are WAY bigger than they look on cam!  Little chunks for sure.  I put each of them into their own cloth bag and brought them inside. First we weighed them. The younger one was 1.0 lbs and the older 1.3 lbs.  Whoa!!



The next step was to put the bands on their legs.  Um, yeah.  The band seemed too small to go onto the foot of the older owl.  DRAT!  But with a little finesse it went onto the foot of the younger owl.  (Later we tried the oldest owlet again.  Hein gently but firmly tucked the front three toes through the band and eased it over the ankle, then gingerly tucked the hallux (hind toe) back through the band.  Hallelujah!)

The owlets were nervous at first and shivering due to their nervousness.  Hearing Rusty and Iris hoot on the monitoring equipment seemed to calm them down and they went to sleep flat out on their stomachs.

A few hours later Rusty woke the owlets up with his hooting and they sat up.  Seemed like a good time to try to feed them, so I cut up the back half of a rat.  I used a long forceps to rub a piece of food up against their bills.  The younger owlet happily accepted, but the older owlet just hissed a bit and gave me a dirty look.  So I played a recording of Iris clucking and feeding the owlets, and that did the trick.  Both ate, and they chittered back to the recording of Iris each time.  Cool that I can test their reactions to recordings now!



Later when Rusty was hooting one of the owlets did a couple of "peep hoots" in response.  I should be able to get some good recordings.  This works well to have them hear their parents normally for natural acoustic stimulation!

They had a bit of active time, preening and looking around, and it seems they are already used to their situation.  Iris and Rusty seemed to adjust within 1-2 hours also, thank goodness.


Now we will learn to work with the technology and expose the owlets to all kinds of people and places so they are comfortable, well-adjusted education birds in the future.

karla@internationalowlcenter.org (Karla Bloem) Blog Sun, 23 Mar 2014 18:40:53 -0500
The Plan for 2014 http://www.internationalowlcenter.org/blog/item/11-planfor2014 http://www.internationalowlcenter.org/blog/item/11-planfor2014

I updated the website a while back and intended to do a live chat session specifically about the topic of the 2014 owlets, but time slipped away from me as I was working on the International Festival of Owls plans and I just plain needed some down time.

The 2014 owlets will be raised different from how Pandora, Patrick, and Patience were reared last year.  This year's owlets will be hand-reared to compare their vocal development with wild parent-reared owlets (the 3 P's) to see if it is the same or different.  It will also allow me to test theories about the meaning of vocalizations by testing the owlets' repsonse to recorded vocalizations.

I will remove the owlets from the aviaries when they are 2-3 weeks old.  They will be reared together in the house, coming to work with me at the Houston Nature Center during the daytime.  I will be working on another more portable cam setup so they can be streamed live from home and work (although we may not include audio at work, and will likely only stream them at home after we have gone to bed for privacy reasons.)  

Once the owlets are starting to fly they will be moved back into the flight pen so they can be watched on the cams out there again.  We will modify the flight pen to lower the ceiling and make their space smaller so that I am able to get them off perches to continue to bring them to work so they can begin their training for their eventual placement as education birds.

Placing the owlets in long-term captive situations as education birds will allow me to track their territorial hoots over their lifetime to see if they stay the same or change.  The value is that if their territorial hoots remain constant, and we can show that individual hoots work like fingerprints to identify individual owls, birds may not need to be captured and marked in future research projects, reducing stress on birds and eliminating the problem of failed batteries in transmitters.

I have chosen this rearing method because I believe it will produce the best possible education birds, meaning they will be very comfortable with their role in life, and they will be easy for handlers to work with.  They should imprint on each other rather than humans, so they should be less likely to be aggressive with their handlers than human imprinted birds.  They will be well socialized with humans so they are not stressed being in front of crowds.

Rusty and Iris will certainly not be happy about their owlets being removed, just as they were upset when I removed their unhatched eggs two years ago.  There is a small chance they may lay another clutch of eggs, but it is likely a little too late in the season for that.

What we find out from these owlets this year will help determine the best course of action for future data collection in this breeding project and determine how future owlets are reared.

karla@internationalowlcenter.org (Karla Bloem) Blog Mon, 10 Mar 2014 09:53:17 -0500