2013 Decorah Eagle Cam Questions

We turned on the Decorah eagle cam this morning and questions are rolling in! Here are the answers to the most commonly asked questions so far:

Where are Mom and Dad Decorah nesting?
They are nesting in the new or yonder nest, henceforth to be known as N2. N2 is about 533 feet or 162 meters east of N1, by the side of Trout Creek. It is 60-70 feet up in the center fork or crotch of a cottonwood tree. The image below shows both nests and the trout hatchery.

N1 and N2. The eagles are currently nesting in N2.
Click the image for a larger view.

What is the diameter of N2?
We didn't measure it exactly, but it is smaller than N1. I'd guess about 4 feet in diameter. This yields a circumference and area of about 12.5 feet. Neil and I were just barely both able to fit into it, and we hung all of the equipment of the side with leashes and anchors.

How deep is N2?
Another estimate. I'd say 3 to 3.5 feet. It was much easier to climb into than N1.

What types of trees did they raid for the railings?
The available kind. Primarily cottonwood, judging from the trees surrounding it. The neighborhood also contains maple and oak, but cottonwood is the predominant tree.

How would you describe the tree trunk joining where N2 is?
N1 was out on a limb, away from the central fork of the tree. N2 sits directly in the tree's center fork or crotch, where the trunk splits to form smaller branches.

How many corn husks were in it when you put up the cams?
None! We installed the cams on August 31. The eagles hadn't yet started fall courtship or nestorations.

Did you leave a food offering when you put up the cams on N2?
We didn't. Fortunately, Mom and Dad didn't mind.

Do the cams bother them? Does the IR light bother them?
The eagles are unable to see IR light. I've got a blog post explaining it here: http://raptorresource.blogspot.com/2012/03/what-is-infrared-light-and-why-cant.html. If you don't want to read the long explanation, you'll notice that the eagles' pupils don't respond to the IR light by contracting or expanding. They can't perceive it and we wouldn't either if the camera wasn't mapping the image down into the visible spectrum for us.

The cam doesn't bother the eagles either: it is fairly small, up above them, and painted drably to stop reflection and glare. The globe is highly smoked enough that I can't see through it. If the eagles can, it is no more alarming to them than anything else - leaves blowing, branches tossing, cloud shadows, squirrels and other animals, and people on the bike path. Their world is filled with movement and sound.

Did you work on N1's cams?  If so, did you see anything that would help speculate on why they left N1?
We didn't go up into the tree - those cams are still running from 2012. We don't know for sure why they left, but there are two theories.

• Theory one: That's what eagles do. In one study of 318 eagle territories in Alaska, 45% of eagles studied had more than one nest on their territory. In another study of 924 territories, eagles were found to have an average of 1.5 nests in their breeding area. N1 was built in 2007. Maybe it was simply time for them to build a new nest. We all know how much time they spend working on the nest.
• Theory two: The old nest was built farther out along the branches of the cottonwood. Its weight was causing it to tilt toward the outside. This could have caused the eagles to abandon it in favor of a new nest. 

I'm more in favor of one, myself, but I'm not ruling out two. For more speculation, check out this blog post: http://raptorresource.blogspot.com/2012/10/the-decorah-eagles-have-surprised-us.html

Coming down the tree

How did you get into the tree?
After making sure no eagles were in the area, we fired a crossbow loaded with monofilament line over our target branch. We used that to pull a four mm cord, which was used to pull an 11mm climbing line. Neil used a frog system and I used a grigri + ascender + carabiner. Neil got up into the nest in about a minute. It took me a little longer. Here are two video links that show the basic technique:

• http://youtu.be/NJHBQVkBxj0 (grigri + ascender)
• http://youtu.be/ZTai7Gd5SaY (kroll frog system)

Coming down was interesting since Neil's rope wanted to pull him away from the tree. We wrapped webbing behind him and I pulled him into the tree so he could run the cable. This worked extremely well.

How many cams are there?
Two - one PTZ and one fixed cam. The PTZ is a mini PTZ and the fixed cam is also quite small. They are painted drably.

Where are they mounted?
The nest is cradled in the center of the tree. The limb on the south side of the trunk shoots out and up. The cameras are mounted a little over where the limb turns up. I'm guessing they are about four feet above the nest.

What kind of cams?
Despite having helped install the cam, and don't know much about them. Both were purchased from KT&C and the PTZ is a mini-outdoor cam.

How long did it take to install the cams?
Bob had everything ready to go and it went very quickly. It took about three hours from the time Neil started up his rope. We got up, installed the two cams, and rappelled down, fixing the cable as we went.

Did the eagles notice or mind?
They did not. As I wrote earlier, We installed the cams on August 31. The eagles hadn't yet started fall courtship or nestorations. The cams themselves are small and painted drably to minimize reflections or anything else that might disturb the eagles.

What Cameras Do You Use?

We get this question a lot - on facebook, via email, in person, and in chat. Unfortunately, the answer is fairly complicated since we've used different cameras at different times and locations. I can't recommend any one camera model, but I can provide some general information about cameras and streaming technology to aid research. In general, we use a PTZ camera and controller, microphone, and computer to capture, process, and unicast video stream to a service provider, who broadcasts it across the internet. To do this, you need to consider...

• Do you have all necessary permits and do you understand the animal you are camming? Permit issues regarding wildlife and cabling may differ from state to state. Make sure you understand your state's process so you aren't inadvertently breaking the law. Make sure you understand your subject so you know when it is and isn't safe to install camera equipment. What will your subject tolerate in terms of camera size and placement? When can you go to the nest, burrow, or what have you without scaring your subject away? 
• Does your installation have electricity and internet connectivity? If you need wireless and/or solar, talk to this company: http://www.sunsurveillance.com/. We've done one wireless installation so far, but most of our installations are wired. 
• What challenges will your camera face? Ice, rain, cold, bugs, poop, and entrails can all damage cameras and impact the view. Depending on the time of the year, you may not be able to access and fix your cameras, so they better be up to the environment and placed where your subjects can't damage them through picking at them, pooping on them, or hitting them with prey. We use weather-hardy PTZ and bullet cams certified to below-zero temperatures. We are also very careful about protecting cables and interfaces from weather, ice, insects, squirrels, and mechanical damage. 
• You've got the camera. How are you going to get your stream to the internet? We use a standard PC, capture card, and encoder to unicast our stream to Ustream, who broadcasts the stream across the internet. Research streaming-video providers and see what they recommend - some of them, like Ustream, provide lists of certified equipment and offer their own encoders. Not all video cards work with all encoders (especially older cards) so research this carefully before buying equipment. This page (from Ustream) provides some information on their platform: http://www.ustream.tv/platform. You should also consider PC versus streaming appliance if you don't already have a PC waiting in the wings. 
• How fast is your internet access? You need to know the speed of the internet connection you can get prior to making some of your decisions. If you have a fast line - say, a T1 - you have different (better) streaming options than you will with a slower line.  

As much as we love watching birds, the health and safety of our subjects is always our primary concern. That's why we decided not to cam the Yonder nest in Decorah - however we might feel about the new nest, the eagles are doing a very natural thing and we don't want to risk frightening them away. Bob has been a falconer for 46 years and has a great deal of experience with birds of prey. I think it is wonderful that so many people are interested in watching and sharing wildlife, but I can't stress the important of knowing and respecting your subjects enough. A few links to aid research:

• Ustream: our streaming video provider
• 2MCCTV: our camera provider
• Sun Surveillance: wireless and solar cameras
• Xsplit: our software encoder
• Trying to migrate an analog system to IP (network) video? Check out the EVE hardware encoder. In addition to encoding it also upscales 525 very nicely.
  

Return to the Nest 2013: Q&A Session

Social Stream moved very quickly during the interview with Bob on Tuesday, September 25th! I wanted to publish his answers to a couple of the very commonly asked questions I saw floating around in the stream, and hopefully answer a couple that he didn't get to.

Before I start with the questions, videos are here:

• http://www.ustream.tv/recorded/25724937 (Bob's interview)
• http://www.ustream.tv/recorded/25708771 (cam set-up)
• http://www.ustream.tv/recorded/25654654 (intro video)

What did you guys do when you installed the cam?

Bob Anderson directed the installation. He designed and tested the equipment, planned and oversaw the deployment, worked with Dave and Neil via the webcam to make sure everything was installed correctly, and staged on the ladder to help pass equipment.

Neil Rettig and Dave Kester climbed the tree. They cleaned the old camera dome, replaced the broken IR cam, removed an unnecessary screw, and added two new cameras: a new PTZ and a very high resolution fixed bullet cam. As Bob pointed out, we'll have new views. You will sometimes be able to see one of the cams appearing on screen.

Jim and Charlie worked on the computer and power protection systems and helped haul equipment.
Amy Ries briefly staged midway up the tree to help get the camera bag up, set anchors, and helped haul equipment.

What is new this year?

We have a new PTZ cam, a new high resolution fixed cam, new views of and from the nest, better surge suppression and electrical protection, new video cards, and a new system to switch back and forth between the cams on site or remotely.
Kudos are due John Howe for designing the switching system, and Kenny from Simms Electronics for his technical assistance and computer systems.

When is the cam turning on?

We don't have an exact date yet. We need to get a T1 line pulled in for faster service and make some changes to our computer system. It will be sometime between mid-October and mid-November.

When will chat re-open?

Chat will re-open in February. We will announce an exact date as it gets closer.

How did Mom and Dad react to the camera installation?

Mom and Dad weren't at the nest when we got there.  They did fly by in the early afternoon and vocalize two or three times before leaving. We saw them briefly soaring over the bluff later in the day, which was warm, windy, and perfect for flying.

Are Mom and Dad already working on the nest?

Yes, they are! They have begun adding crib rails to the side in preparation for next year's brood.

Were you able to get permission to lighten the nest? Who would you get permission from?  

The US Fish and Wildlife Service oversees permits and other issues related to the Migratory Bird Treaty Act, including falconry, raptor propagation, scientific collecting, special purposes (rehabilitation, educational, migratory game bird propagation, and salvage), take of depredating birds, taxidermy, and waterfowl sale and disposal.  We have permits to go into the nest and install cameras, and we have permits to band and attach transmitters to eagles, but we did not get permission to lighten the nest this year.

Bob pointed out that Neil, Dave, and all the gear weighed more than the eagles were likely to bring in this year, so we think the nest will be fine. We'll probably ask again next year.

Did you leave a treat for the eagles?

We usually do, but we did not this year. Fortunately, they didn't seem to hold it against us.

Is the crossbow dangerous to the eagles?

We use a dull bolt, but we also don't shoot the crossbow when the eagles are in or near the nest. We don't want to take any risks with them.

Will Mom and Dad migrate?

Probably not - they have a history of staying through the winter. Eagles are partial migrators - that is, some eagles migrate and others don't. For eagles to be non-migratory, there must be sufficient food during the winter.  The Decorah eagles have a nest in a relatively sheltered location, with ample access to food year round. The adults are not migratory.

Are D13 and D14 still around?

Yes, for D14, although we haven't seen D14 at the nest. D14 spends a lot of time NW of Decorah, near the Upper Iowa river. He has been seen in the company of other adult and hatch year eagles, but we don't know whether those eagles are family members. It is certainly possible, although there are other eagle families in the area. You can follow his adventures at: http://www.raptorresource.org/maps/D14_latest.php

Probably for D13 - D13 was believed to be spotted recently, but we don't know for sure.

Why do these eagles always lay three eggs?

They don't - in 2008, her first year at this nest, Mom laid a two-egg clutch. She has, however, laid three egg clutches every year since. Three egg clutches are not common in Bald eagles.  According to Gary Stahlmaster:

• 79% of clutches have two eggs
• 17% of clutches have one egg
• 4% of clutches have three eggs
• Less than 1% have four eggs.

Food availability impacts Bald eagles in a number of ways, although there is a lot of debate about whether or not it impacts clutch size.  Some studies say 'No', while others hint at a link. Our nests don't make it any clearer either way: one nest (the Decorah nest) has a reliable high-quality food supply in a relatively sheltered area, while the other nest (the Fort St. Vrain nest)  is at the foot of the Rockies in an area with harsh weather and a more limited food supply.  Yet the eagles at both nests have a tendancy to lay three egg clutches. We don't know why.

Are you going to turn the nightlight off this year?

No: the nightlight is infrared light, which the eagles can't see. Click here for more information on the IR cam.

Are you going to have cameras in the kestrel nests?

We don't have any plans to do so right now. The kestrel project is a pilot that explores using county right-of-ways along gravel roads to expand the kestrel population. We don't easily have a way to get power or connectivity out to the boxes, which are located in remote areas. If you would like to learn more about that project, click here.

What was that about Philippine Eagles?

The Raptor Resource Project will be working with the Philippine Eagle Foundation to raise awareness of the highly endangered Philippine Eagle. From the foundation:  The Philippine Eagle Foundation firmly believes that the fate of our vanishing Philippine Eagle, the health of our environment, and the quality of Philippine life are inextricably linked. We are therefore committed to promote the survival of the Philippine Eagle, the biodiversity it represents, and the sustainable use of our forest resources for future generations to enjoy.

We plan to add a Philippine Eagle cam and help sow the seeds for a recovery effort for and by the Philippine Eagle. We will post more about that as it gets underway.

Thank you for watching!

What is infrared light, and why can't eagles see it?

We are starting to get a lot of questions about the night-time illumination of the nest, so I thought I would write a little bit about visible light, invisible light, and our IR illuminators. What we see - the world of visible light - is just a tiny fraction of all the types of light that exist. Infrared light, gamma rays, X-rays, ultraviolet light, microwaves and radio waves are all types of invisible light. Like visible light, they are different because the length of their waves is different.

The illustration below shows the electromagnetic spectrum in its entirety.  The IR portion hangs just off the red end of the visible spectrum.  It spans the frequency range from 780 nm to 300,000 nm (.78 to 300 um) and has a longer wavelength and lower frequency than visible light (click the image to embiggen it):

Illustration courtesy Wikipedia: 
http://en.wikipedia.org/wiki/File:EM_spectrum.svg

Birds have very different eyes than we do. They have four color cones instead of three, more cones and rods to see color and light with, a higher proportion of cones to rods (at least in diurnal birds), and different peak sensitivities to light. As the graph below illustrates, we have narrower spectral sensitivity than birds and are much less sensitive to certain wavelengths of light. However, like humans, birds do not see above about 700 nanometers. While some birds range into UV, IR light is as invisible to them as it is to us.

Illustration courtesy of "Color Vision in Birds": http://www.webexhibits.org/causesofcolor/17B.html

So how can we use an IR illuminator to see the birds if we can't see IR light?
Researching and writing about this stuff makes me want to read a trashy romance novel, but I'll put that aside for now and forge ahead. Here is how it works. The IR spectrum starts at about 780 nm. The LED IR illuminators used on our camera emit 'invisible' light at a wavelength of 850 nm:  well above the 700 nm visibility limit we share with birds, but well below the high-energy 'hot' end of the spectrum.  LED illuminators are also smaller and have lower requirements and range than bulb-type illuminators.

The camera and illuminators are located roughly five feet from the eagles. The illuminators shine IR light on the nest. The IR sensor detects the light and focuses it onto a CCD (Charge Coupled Device) imager chip, which has a spectral response of up to roughly  1,000nm. The chip maps IR wavelengths of light down into the visible spectrum via tiny electric charges generated by IR light falling on to an array of tiny sensor cells. Since the photo-sensitive cells don't distinguish between colors, the camera generates a monochrome image. I suspect it is really a LAB color space, but that is far outside the scope of this discussion. If you feel really nerdy, follow this link to learn more about LAB color spaces. There is a lot more to color than RGB, even for us trichromates! http://en.wikipedia.org/wiki/Lab_color_space.

Can the eagles hear or see the PTZ camera?
The cameras use servo motors to drive the camera along a 360 degree path, which minimizes the amount of time and work it takes to arrive at any given destination. These motors are very quiet - the camera was designed for surveillance - and encased in hard plastic. I suspect that the eagles can't hear the servos; certainly, we don't hear the servos and the microphone is much closer to the camera than to the eagles. If the eagles can hear the servos, the sound is not any more alarming to them than the other noises that make up their sonic landscape - traffic on the nearby road, people at the fish hatchery, wind, tree branches, the brook, the horses, and so on.

Although the young eaglets went through a period last year of seeming quite fascinated by the camera - we wondered if they were interested in their reflections - the eagles ignore it generally. Since it rotates around a 360 degree axis, there does not appear to be much movement (think of a spinning top) and the camera is behind a dome, which helps conceal it. If the eagles can detect movement, it isn't bothering them. Again, a lot of things around them move. Since the camera isn't trying to eat or threaten them, it doesn't really concern them.

In short...
Mammals and birds can't see IR light - to the eagles, the nest is dark at night - but our camera can. We use low power IR illumination devices that are roughly five feet from the eagles. They are not hot and do not emit dangerous radiation or noises. A chip inside the camera does the work of converting the IR image into visible light via tiny electric charges. However, because the chip does not detect color, the image is monochrome.

Experimenting with IR light
To see IR light for yourself, take a television remote, which works via IR. Press a button and look at the LED on the end. You won't be able to see anything. Now, take a digital camera or phone camera (I used an Android HTC), point it at the remote to take a photo, and press a button on the TV remote. You should now, through a digital device with a higher spectral sensitivity than either we or the eagles have, be able to see the infrared light. Like our camera, your camera uses a CCD chip that maps IR down into visible light for humans. But neither we nor the eagles can see IR without technological assistance. Again, the nest is dark at night.

What about the cameras?
A lot of people are interested in knowing more about our cameras. Read this blog post for more information: http://raptorresource.blogspot.com/2013/01/what-cameras-do-you-use.html

The following sources helped me understand all this:

• Personal communication with Travis from 2mcctv, aka our camera salesman. Thanks, Travis!
• http://www.dptips-central.com/infrared-light.html (cameras and infrared)
• http://miguelpedroso.com/Articles/article_nightvision.pdf (light and IR illuminators)
• http://www.onceinnovations.com/downloads/spl.pdf (The Science of Poultry Lighting)
• http://en.wikipedia.org/wiki/Bird_vision#Light_perception (bird vision)
• http://www.jaycar.com.au/images_uploaded/ccdcams.pdf
• (CCD camera explanation)
• Color Vision in Birds": http://www.webexhibits.org/causesofcolor/17B.html
  color vision, birds, and much more
• My husband Ken, who came up with the real-world experiment.