All the little bird babies

Tonight Gabby and Samson have both been on the nest looking at their little one.

Samson and Gabby looking adoringly at N24. @NEFL and AEF

Observers over the last few days have mentioned how attentive the two parents have been since it was discovered that N24 has Avian Pox. Lesions were first noticed by AEF monitors on 20 February. The lesions became more noticeable and by 27 February many citizen-birders were reporting them in FaceBook posts and videos.

I wanna be pretty like you. @NEFL and AEF

Gabby and Samson look at their baby who was born on 8 February. It is 23 days old. Little N24 is full and sleeping with ‘its egg’.

Thinking about their baby. @NEFL and AEF

Little N24 has a very good appetite. And that is such a positive thing. Yesterday, despite a late delivery of food, he ate really, really well. And today, he has another fantastic crop. The crop stores food. The eagle can do a crop drop when its stomach is empty. The crop is like a holding area for additional food.

Oh, yum. I like it when my dad feeds me. @NEFL and AEF
My mom is going to send an order for more fish! @NEFL and AEF
Fish dreamin’. @NEFL and AEF

The lesion that was on the left side of the mouth appears smaller today than it was yesterday.

Avian Pox lesions. 2 March 2021 @NEFL and AEF

I tried and tried to get a proper close up and just kept missing the opportunities. The nest has several cameras and the best one to get the left side of N24’s face has had some condensation on it. So, it is not easy to compare because of the angle, the distance, and the lighting but it does seem like the right side of N24’s mouth has made some improvement in healing. It takes 1-4 weeks for the lesions to dissipate.

Why is my head still fuzzy? @NEFL and AEF

You can still see N24’s crop at 6:48pm when he is watching some interior decorating happening in the nest. N24 is alert, moving around the nest, eating well, and growing. Let us all continue to send warm wishes to the little cutie pie with ‘its egg’ for a complete recovery.

My parents think the rails need to be a little higher on my crib. @NEFL and AEF
Oh, that fish was good! @NEFL and AEF

Flight feathers are starting to grow on N24’s wing tips. The itchy stage is coming.

Gonna get itchy soon! @NEFL and AEF

In the image below, the little cutie pie is sleeping, sitting up like Gabby, its mom, with its head tucked under its wing. They are both incubating ‘the egg’.

I Wanna Be like my beautiful mom, Gabby! @NEFL and AEF

It is impossible to keep track of everything going on in all of the nests. As Bald Eagles around North America lay eggs or eggs start to hatch, there is a lot of activity. The hawks and falcons are renovating nests and the Ospreys are migrating home. One thing for sure – there are going to be a lot of bobble heads within the next 4 to 6 weeks.

At the Duke Farms nest in Hillsborough, New Jersey, chick 2 hatched at 1:03 am on 2 March. Both of the little ones are doing fantastic. Aren’t they cute? Eaglet #1 got a chance to have eel for dinner the other day. Looks like it is fish in the pantry today. All of these fathers are great providers.

Two perfect little bobbleheads. @Duke Farms.

If you would like to keep up with these two (and maybe a future three), here is the link to the Duke Farm’s streaming cam:

The Great Horned Owl that borrowed the Bald Eagle nest near Newton, Kansas is still incubating eggs. Some are expecting there to be a pip watch in the coming days.

Bonnie in the warm late afternoon sun. @Derek the Farmer

Bonnie’s mate, Clyde, often stays on the branch above the nest to protect her and is busy at night furnishing her with ‘Mouse Take Away’. Bonnie and Clyde are fierce predators especially during nesting season. Remember that they stood their ground with the Bald Eagle and did not relinquish the nest once Bonnie had laid her egg. We still do not know how many eggs Bonnie is incubating. There could be any where from 1-5. Bonnie has not given any secrets up! Her owlets will be born with whitish-grey down with a little bit of brown. As they mature, they will become more brown.

Did you know that the tufts (they are not really horns) of hair on the Great Horned Owls are thought to break up the profile of the head to improve their camouflage abilities? Their short curved feathers mean that they are silent night fliers. Indeed, these large owls are notorious, as of late, for knocking Bald Eagles off their branches in the night. Just the other evening, a GHOW knocked Harriet off her branch at the SWFL Eagle Nest and into the nest bowl! GHOWs will hunt large raptors such as Ospreys, other owls, and Peregrine falcons for food. They are equally happy to have reptiles for dinner as well as mice, fish, insects, worms, and rats.

And so happy to report that the mother and eaglet at the Kisatchie National Forest Bald Eagle nest are also doing fantastic. It has been raining alot and this mother is a really good ‘mumbrella’. Both of them have figured out the feeding and the little eaglet is growing.

Oh, I love my fish dinners! @KNF Bald Eagle Nest, Central Louisiana.

And another really good news story. The ‘Old Warrior Eagle’ that had broken its leg and had its beak injured early last fall was down, emaciated, and full of lead toxins. If you are any raptor and have that many problems, the best place to be found is near A Place for Hope in Connecticut. The Old Warrior has been on Clemation Therapy to get the lead out of his system. When he came in, the levels were over 48. Look at the levels today:

This is a huge drop in the lead. This eagle is lucky. Most die. A Place Called Hope FB Page.
Old Warrior and his injuries. A Place Called Hope FB Page.

He is going to be so excited to be outside in the aviary!

Look at that face. And those beautiful big eyes of this Peregrine Falcon. He was attacked by a cat. And, lucky for him, he is there in the same clinic with the Old Warrior. Get well soon! You are adorable. I could just scoop you up and take you home. Would you like to live in Canada?

Please keep your cats inside! A Place Called Hope

Take care everyone. Thanks for dropping by and for caring about all of the wildlife.

Thank you to A Place Called Hope for the images on their FB Page. Thank you to the KNF Eagle Nest, Duke Farms, NEFL and the AEF and Derek the Farmer for their streaming Cam. Those streams provided the screen captures.

Milestones

Birds have developmental ‘milestones’ just like humans. Right now there are so many Bald Eagle nests where eaglets are already two or four weeks old. In others, the parents are incubating eggs. And there are others where the parents are only beginning to start working on the nests. You can see every stage of a Bald Eagles growth from the female laying the egg to their fledging from the nest on the many streaming eagle cameras. Every eaglet is different, just like people and their development will not happen on a single specific date.

Within the overall umbrella of bird development, you might remember Daisy the Duck (see previous blogs for more information on this remarkable little duck). This Black Pacific Duck laid her eggs in the Sea Eagles nest. We knew that the ducklings would jump from the nest 24 hours after hatching if we actually got to hatch – which, sadly, we did not. Those ducklings could see, forage, swim, and take care of themselves without help from the parent. Daisy would, still, gather them up and protect them during the night. Fully independent of their mother, those ducklings would have been ‘precocial’. In contrast, the eaglets are not fully developed, nor are they able to feed themselves, or fly down from their nest. Indeed, they are covered with fluffy down but are unable to regulate their temperature.

It takes from ten to thirteen weeks for eaglets to fledge whereas the ducklings do this at twenty-four hours. Eagles as well as all other hawks or raptors are ‘semi-altricial’. This means that they will be dependent on their parents for everything they need until fledge. Even after fledging, the parents will teach them to hunt and will provide prey supplements for them.

Until the onset of streaming cams, there was very little quantitative information on the development of Bald Eagle Nestlings. Today, there are cameras, often more than one, on nests around the world. You can, at any time of the day, watch Bald Eagles, Peregrine Falcons, Golden Eagles etc. at your leisure. The growing community of citizen birders has impacted the knowledge of avian development and behaviour considerably. We are, indeed, continuing to learn every day. Advances in satellite transmitters means that birds can now be studied after leaving the nest providing much information about foraging, distance from natal nest to establishing their own territory, etc. This blog today is general and non-scientific in its terminology.

Many look at the development of Bald Eagles through three stages: structural growth, feather growth; and behavioural growth. Others attempt to combine feather growth with behaviour and structural development into weekly goals. In fact, I have pondered over this blog and how to approach it for several days because there are different factors that impact development. One of those is gender. There are also studies that have shown that the levels of salt in the diet impact growth while others have examined the amount and quality of prey. We know from studying Red Tail Hawks that if you double the amount of prey and the eyases remain in the nest for several days beyond the average, they are better equipped to fly and hunt. Their overall condition is much stronger. For the purposes of our discussion, I have used evidence from the NEFL Bald Eagle nest in 2021 and the SWFL Bald Eagle nest in 2021 and 2017 (E9). There is one eaglet on the NE nest and two on the SW nest in 2021. The parents on the NE Florida nest are Samson and Gabrielle. Samson was born on this nest on 23 December 2013. He is a little over seven years old. We do not know the age of Gabrielle. At the SW nest, Harriet is in her mid-twenties and M15 is 11 years old. Both nests are located within close proximity to a city – Fort Myers and St Augustine. The Fort Myers nest is unique in that the D Pritchett family has a working farm on the land where the nest is located. They also stock a pond in close proximity to the nest specifically for the eagles. This means that there is always food available. Still, the parents bring in road kill as well as fish from the pond. The NE nest does not have this advantage but nest observations reveal that there is an abundance of food although the variety might not be the same as the SW nest.

Both E17 and E18 were born on 23 January 2021. N24 was born on 8 February.

The first week of their lives, eaglets are covered with fuzzy down. The proper term is natal down. They can sit up but it is difficult to support their heads and focus. You can see the white dot indicating the egg tooth. This will disappear later. They use the egg tooth to break through the thick shell. This is often called the ‘bobble head’ phase. Their heads are big and they do not yet have the neck strength to keep them upright at all times. Their eyes are adjusting to focus. Sibling rivalry might already have started. As the days progress, the eaglets will get the strength to hold up their head and balance it. They will also be able to focus with their eyes so they do not look like they are using their beak like a dart but with a moving target (often their sibling). While the bobble head stage is very cute, it is often a relief when the eaglets are more stable.

SWFL nest 2021. Sibling rivalry began immediately. E17 is on the right and is only two hours older than the twin, E18. This rivalry persists but has dissipated to being only occasional and directly related to feeding.
The egg tooth is clearly present on the eaglet to the left.

By week two, the eaglets will be observed crawling out of the nest bowl. They are not walking. They are crawling. N24 is using its feet and wings to help it get out of the nest cup and up to the pantry. It is five days old! Food is a great motivator! Samson has the little one ‘working’ for its dinner. This helps to strengthen its wings and legs. In the Captiva Florida Eagle nest, Peace climbed out of the nest bowl towards the food on day 2. The inclines of both nests are different. The parents present the eaglets with challenges to help them develop their strength such as stretching their necks, grabbing and holding food, working their legs and wings. It’s like having your own personal trainer!

N24 crawling out of the nest cup on 13 February 2021, 5 days old

The beak will begin to grow and the little ones should begin shooting the ‘ps’ out of the nest bowl by the end of week one or beginning of week two.

N24 doing a great pose to get that PS clear of the nest. Watch out mom!

The eaglets are more observant of their world. They will have doubled in size from the day they hatched and their eyes and beak continue to develop. You will begin to notice that pin feathers are growing in at their wing tips. They will start to stand keeping their balance with these wing tips.

N24 12 days old. Notice the feathers coming in on the wing tip (left side)

More feathers begin to appear on the shoulders and the back and the wing feathers are getting longer as the days progress. They are starting to wing flap and they will try picking up food.

N24 wing flapping, 12 days old

N24 is twelve days old in the picture above and the one below. In the one below, you can also see the pin feathers right at the tip of the wing starting to come in. N24 is also standing for several seconds, getting its balance, and flapping those wings.

N24, 12 days old. Wing flapping.

During the third and fourth week, a pattern of accelerated feedings and growth begins. Head and chest are still showing signs of some fluffy down but more dark feathers are starting to emerge.

E17, SWFL Nest, Age 31 days

The eaglets are actively preening those feathers to help condition them as well as to help stop what some say is an itching as the feathers grow in. There is more wing flapping and the eaglets stand with confidence and stability. During this time you will see attempts at standing and walking. They begin to make some effort at self feeding. They are eating much more at each feeding often lunging at the parent to take the food out of their beak. Many observers say that their crops appear like they could burst! These big feedings often result in the eaglets sleeping immediately after a feeding. This is a ‘food coma’. The enlarged crops are extra storage spaces where food is held before being ‘dropped’ to the stomach. Sometimes people call this accelerated growth period the ‘clown feet’ era because the feet seem to grow way out of proportion to the rest of their body. They will also cast pellets. Pellets are food that is undigested such as fur and bones. Pellets are compressed into a hard shape and regurgitated. This often involves coughing and sometimes the eaglets appear not to want to eat the day the pellet is cast. This level of peak energy demands appears to begin to wane after about five to six weeks.

E18 has its wings dropped while sitting (eaglet on left). Crop is full. 23 February 2021.

Beginning around week five to eight, the eaglets often sit with their wings drooping (getting heavy). Hopping and flapping wings occurs more often. They are very interested in what is happening outside the nest. By the end of this period, they will begin to have more of their juvenile plumage colouration. They will be able to hold food and tear bits. They will begin to mantle food. Mantling is the covering of food with the wings in order to have the prey item to themselves. They will stand for longer periods of time and are able to walk easily by the end of the period.

From week nine to fledging. The feathers will become more defined over their entire body and they will stand for longer periods of time upright. They can stand easily on one leg. The hopping, jumping, and flapping of wings accelerates. They are self-feeding but the parents will also continue to feed them. They will now spend their nights sleeping upright like their parents with their head tucked under their wing. They can easily perch on the edge or rim of the nest and will be branching, hopping up to a branch and back down into the nest. Branching tends to occur from seven to ten days before fledging, generally.

Juvenile feathers are not all in. E9, 2017.
E9 Branching, 2017.
E9 trying out a thinner branch, 2017.

It is always exciting to see the eaglet hatch and sad when they fledge. Unless there is a transmitter or bands, they fledge and there whereabouts often goes unknown. Once they are wholly independent of their parents, the juveniles need to find their own territory and source of prey. Sadly, fifty percent of all first year eaglets perish while ninety percent of all year two eaglets tend to survive. The average age of maturity for Bald Eagles is five to six years although there is a young sub-adult male who is incubating his first eggs with his mate in Minnesota right now.

Thank you so much for joining me today. Stay safe. Be well.

Thank you to the Eagle streaming cams at NEFL and SWFL as well as the D Pritchett family. The scaps came from their streams.

Fun with Bonnie and Clyde

Great Horned Owls (GHOW) are found all across North America – literally, they exist everywhere from the hot swampy areas of Florida to the deserts of the Southwest to the prairies and mountains of Canada. There is currently no concern for them in terms of declining populations. Just because there is no decline does not mean that the owls should not be monitored. Monitoring means that researchers can see when a decline does happen and they can ask why.

The setting sun on Bonnie.

In the 1970s many bird populations were wiped out due to the use of DDT. DDT was a pesticide and it was banned in 1972 after Rachel Carson wrote Silent Spring in 1962 exposing the issues. It took a decade for change to happen but it did happen.

So the question then is, why in 2014 were birds dying in Michigan with levels of DDT poison so high in their brains that no one could believe the readings? Songbirds such as Robins, European Starlings, and bluebirds were dropping dead in people’s yards. DDT was not only found in the brains of the dead birds in enormous concentrations but it was also found in the worms that the birds ate. A professor at the University of Michigan looking into the phenomena found that the concentrations ranged from 155 to 1043 parts per million with the average being 552. The threshold for death is 30 parts per million. DDT persists in the soil and in the rivers. It thins the eggs of birds so that they break and cannot be incubated. It makes the birds sick and it is not a quick death but a slow painful one. The authorities in Michigan found that the Velsicol Chemical Corporation was responsible. Under their old name, Michigan Chemical, they manufactured pesticides. It is the area around their old plant where the soil, in 2014, was still saturated with the poison.

Today, the raptors – not the seed eating birds – have issues with various types of designer poisons for mice and rats. They are commonly called Rodenticides. In the United States, the name of one of the biggest companies manufacturing this poison is deConn. And, like when we want a tissue for a runny nose, many will ask for a ‘Kleenex’. Owls eat a lot of mice and rats. In fact, they are the absolute best and cheapest way to rid an area of these rodents. Someone could start a company, ‘Hire an Owl’.

And speaking of owls and mice, I have some great shots of Bonnie and Clyde for you tonight. And I have the answer to two questions sent to me by e-mail. I will incorporate those in the text. Thank you to those who wrote and asked – always happy to answer if I can or to help find the answer.

First of all, owls are noctural but like all other raptors they actually do a lot of hunting right at dusk and dawn. Owls do not see colour very well because nature provided them with sensitive dark-light rod cells instead of ones for differentiating colour. During the day, Clyde will sleep just like Bonnie, if she can. Clyde will not bring food to Bonnie during the bright light of day. But you might expect him to come, if prey is plentiful, right after dusk. Let us hope that none of the mice or rats that Clyde brings Bonnie have eaten any pesticides.

Dusk was at 6:39 pm in Newton, Kansas where the Bald Eagle Nest that Bonnie and Clyde are using is located. Between 6:55 and 8:04 pm, Bonnie made three trips off the nest. The first was at 6:55. She raises her head. Did she hear Clyde? She leaves the nest and returns at 7:03. That was eight minutes. She might have needed a bathroom break and she might have had something to eat.

At 7:21, we can see Clyde’s eyes. Clyde lands on a branch. Bonnie hears him.

Bonnie gets up. Clyde has brought her a mouse!

They do a quick exchange.

And Bonnie is back on the nest. It took a whole two minutes.

Bonnie takes another very short break from 7:57 to 8:04. Just like the first time she left this evening, the camera is fixed on the next so we cannot see what happens outside the frame. The temperature has really warmed up from the frigid minus degrees. It is 29 degrees F. The hunting might be a lot better because the mice will not be hunkered down with the cold. They will also be out looking for food while Clyde is looking for them!

Those beautiful big owl eyes are the reason that Clyde will be his busiest hunting within two hours of dusk and two hours of dawn. It is quite possible then that all three of Bonnie’s departures after dusk had to do with food deliveries and bathroom breaks together.

It is dawn, 6:27 am at the nest and Clyde has brought in his last mouse for the night. He arrives on his ‘regular’ branch. You should be able to see the mouse hanging out of his beak.

The pair have this all worked out. Bonnie and Clyde do some hoots and she flies up to the upper branch on the left.

Bonnie then flies up to grab the mouse from Clyde and within a blink that mouse becomes owl and she is back on her nest in two minutes. This couple is extremely efficient!

Besides hunting, Clyde’s other duty is to protect the territory of the nest and Bonnie. He will not be far away!

__________________________________________________________________

Just a couple of quick observations for today and then something special at the end.

The little eaglets on the Southwest Florida nest at Fort Myers, E17 and E18 are itchy. E18 was preening 17 and then they both wake up in the night and start preening. You will see that their flight feathers are just starting to come in. (Note: The dark object is a piece of an armoured fish). Here are a few images of these two itchy characters:

E17 is preening E18
Flight and pin feathers make eagles itchy.

Over at the other eagle nest in NE Florida at St Augustine, little NE24 is getting its pin feathers, too. Sometimes these are called ‘blood’ feathers because they are filled with blood while they are growing. Some of you might remember that Hope, the oldest eaglet on Connie and Joe’s nest at Captiva, Florida died because she broke a blood feather and bled out. That was because of the rodenticide in the prey she had been fed. So blood feathers. Our new words for the day!

I am absolutely in love with this little eaglet. Maybe because it is all alone on that big nest without any siblings. But, at the same time, that is such a plus. There is no anxiety watching this nest. Gabby and Samson do a fine job taking care of this little one. And its eyes cleared up all on its own.

The soft glow of dusk is filtering through the trees in the swamp. NE24 has a nice crop before bed. You can see that the feathers are changing colour from white to grey. You can also see the pin feathers just starting to come in. Poor thing. It will not only have to deal with all those mosquitoes but now these things coming in!

Now for something just a little special. Most Bald Eagles do not start breeding until they are much older than five years even though they can at four to five years. In a nest in Minnesota supervised by the Department of Natural Resources, a four year old Bald Eagle male (called a sub adult) is going to get to see his first egg for the very first time. His beak is still a brown or amber colour instead of the bright yellow and he still retains some of the brown feathers mixed with the white on his head. It is thirteen minutes long – and no, he is not dirty. He is just a youngster. His eyes have not gotten light yet either. Enjoy!

Thank you again for joining with me to learn about the birds we all love so much. It is my pleasure to share them with you. Tomorrow we best check in on some Royal Albatross and what their satellite trackers are showing and we will also try and find Solly ——- and, of course, see what Bonnie and Clyde are up to. The weather patterns are shifting again and I am sad to say that the Bald Eagle Nest in New Jersey is once again covered with snow. This mom with three eggs under her never seems to catch a break.

Thank you to the streaming cams of Derek the Farmer, Duke Farms, SWFL Eagle Cam and D Pritchett Real Estate, NEFL Eagle Cam, and to Lady Hawk for making that great video of our young eagle dad.

Feathers and Preening

You have probably never thought much about feathers unless you raise chickens and wind up plucking them yourself. Or your duvet is full of down and feathers and you find them all over the place if there is a small hole. But, maybe, like many of us, you wish you had wings and could fly – like Icarus – but not with the same consequences. I wish I had feathers and wings because then I would soar into the sky as high as I could go!

Before I begin, this posting is not the definitive answer to everything about feathers or preening. But I hope to give you a glimpse into the importance of both to Red-tail hawks. Sort of a nutshell version. If you are really interested in feathers and believe me, there is a lot to learn, I have included the name of a good book later in this blog.

Red-tail hawk chicks begin to jump and flap in the nest, according to my observations, approximately 2-3 weeks after they hatch. They are building the muscles in their wings when they flap and flap. Flight feathers not only help birds fly and soar but they are contoured and offer protection from the weather. In the first photo below, there is a snow and ice storm in Ithaca on May 8. Big Red’s feathers are keeping her dry and also protecting the chicks. Look carefully at the one under her beautiful red tail feathers.

Feathers keep birds warm and dry – in ice, rain, and snow. The chicks have not yet developed feathers to do this so Big Red covers them.

Several times this spring, the rain has just been torrential in Ithaca. Again, the feathers kept Big Red, no matter how drenched she looked, dry and in turn, she spreads her wings to keep the chicks dry and warm.

For us newbies, we were worried about Big Red in all the rainy weather. Here she is covering the chicks. They get so warm that they often stick their heads out just to get cool. And just a note. Both Big Red and Arthur have brood patches where their feathers have worn down from incubating the eggs and then protecting the chicks.

When it is really hot and humid as it is in both Ithaca and Syracuse the last few days, rain can be very welcome to hot hawks. Below is an image from the Syracuse University Hawk cam showing two of their newly fledged red-tails dancing in the rain to cool off. It reminds me of being in India in the late 1980s and 1990s. You would beg for the rains to come to cool off and would run out into the rain ever so thankful!

So remember. Flight feathers are not just for flying but they are also for protection from the weather. The water resistance from the feathers comes from hydrostatic pressure. Hydrostatic pressure is the tension between the structure of the feather versus the pressure of the water. Water droplets bead on the feathers.

Arthur leaving to get prey for the chicks with Big Red giving him directions. Notice his legs tucked up and the slight curve of his wings at the end and, of course, that beautiful red tail.

Wing feathers are the longest and the most useful for flying. Below is a closeup of one of the chicks with their wing feathers starting to grow. Also notice the tail feathers that are beginning on the chick and the recognizable “red tail” of the Red Tail Hawk on Big Red. The chicks will not get their beautiful red tails until they are in their second year. Tail feathers are like the rudder on a boat. They help the birds manoeuvre. About a month after they have fledged, the chicks should be able to soar into the sky.

Approximately 18% of the weight of a Red-tail Hawk comes from feathers. By the time the chicks are 29-31 days old, their dorsal wings should be 90% feathered. Their legs will begin to feather and they will get the characteristic “pantaloons”. The ear openings should be covered and the upper tail coverts should be well developed. By the time they are 35 days old (about a week from a possible fledging or first flight off the nest), the head will be at least 50% feathered, the dorsal body will be 95% feathered, and the breast should be 90% feathered. Their tail feathers should be five to six bands long, preferably. The more bands the more successful the first flight will be.

This chick is J3, the youngest. He is 31 days old. Note the distinctive “peach” on the breast, the lovely dark feathers marking the “apron” below the crop. The downy head is beginning to gets its feathers and the feathers covering the legs are there.

At the time these chicks fledge, their wing and tail feathers will be longer than their parents. With their first molt, they will return to normal. Molting is the falling out and gradual replacement of the feathers.

There is a really good book on feathers. It is Feathers: the evolution of a modern miracle by Thor Hansen. There is so much to learn including every part and its function! Apparently humans have the DNA to grow feathers but we don’t have the “switch” to turn it on and off. Feathers are much more efficient than their hair. Hawks also use their feathers like a sharpening tool to keep their beaks in perfect condition.

The simple definition of preening is that it is cleaning and maintaining the feathers. Preening reinforces and conditions the surface of the feathers with gland oils. These gland oils contain vitamin D. When the feathers are exposed to sunlight after preening, the oil works as a protective conditioner. The oil in the glands change composition during the year just like you will, if you live in a cold climate in the winter, change the weight of your oil in your car. Red-tail hawks spend approximately 77% of their time preening.

This is an example of a warble. This is when the head of the bird is folded all the way back and down and they are preening their wings
The chicks learn quickly how to balance themselves on branches or metal railings and preen at the same time!

One of the things that I found most interesting about the feathers is that because they are hollow, some researchers understand that birds can feel the changes in barometric pressure and will know what weather conditions are approaching. They are more likely to know the precise weather approaching than the local weather station. They have to. They live outside in the trees, roost on the ledges of buildings, and depend on millions of years of evolution to give them clues to nature’s mysteries so they can survive.