Let it fly…

Observation date: 23 April 2015

peregrine on Chimney Rock

A favorite place the peregrines bring prey to eat                                    Photo by Bob Isenberg

Soon after I arrived at the rock this morning, within minutes the tiercel careened into the nest site carrying prey. I could hear squealing coming from inside the hole where he landed. They should be six days old today and becoming ravenous. He had brought in three prey items in 4  1/2 hours. Sometime after the first hour of observation, I was watching him as he launched off a high perch then across the bay at speed towards where the south jetty meets the sand spit. As he stooped to a flock of shore birds, I lost sight of him in the dark background of vegetation, then caught sight of him again as he swooped up into the grey sky.

I had my back to the nest site overlooking the bay when someone yells, “There goes the female.”

I look up to see her going over my head out to meet the tiercel as he is incoming. A food exchange takes place 300 yards out over the bay. I thought she might eat it herself, but instead went straight to the nest site for a second feeding.

On the tiercel’s third foray, he made it all the way back to the nest site with no exchange. Within seven to ten days we should see one or more chicks make their debut at the edge of the eyrie to defecate. This first sighting never ceases to amaze me, as they are totally fearless, just inches away from death, teetering on the lip of a hole with nothing below, but a sheer rock face 200 feet down.  They then turn around, bend over and let it fly! If we were to try this, most of us would be experiencing the “pucker factor.”

Happy trails, Bob

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Timing is everything…

Observation date: 16 April 2015

Bob Isenberg, listening device, Morro Rock

Bob  Isenberg using the listening device to catch the sounds of chicks                     Photo by Heather O’Connor

And because timing is everything, for the last three days I have spent 23 hours trying to observe food going into the nest site, but with no success. I have seen other indications which you would consider consistent with live chicks in the nest, (i.e., where the tiercel has been very aggressive towards gulls and vultures venturing anywhere near the nest.) This behavior is normally seen during courtship and breeding, such as “showing off” for the female or when young are present.

According to my calculations, today would be the 34th day of incubation. If I was close, they should have hatched within the last couple days. But seeing that I have only been right once in fourteen years, I’m right on track.

Today we did have a nice surprise for visitors and friends of PCPW in the form of a single Black Vulture (Coragyps atratus). These we observe in Morro Bay every couple of years.  Although the peregrine didn’t chase him, he had tangled with at least six Turkey Vultures (Cathartes aura) in three days and many Western Gulls (Larus occidentalis) to the cheers of the many onlookers as the feathers float down from above.

Tomorrow I will set up a listening device to see if I can hear anything in the nest.

“Til then.”… (Decca 1944)     😉

Happy trails, Bob

Item:
Visitor: “Well, Bob, it’s past the fifteenth of April.  Where are the chicks you said would hatch?”
Bob: “You want to see chicks?  Come back in May!” Sometimes I think that is what I should do.

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Patience, please…

Observation date: 8 April 2015

Morro Rock falcons, Bob Isenberg, Morro Bay, CA

Visitors to see the nest site at Morro Rock                             Photo by Heather O’Connor

As of today, we are in the 26th day of incubation and all is well. Two years ago, she abandoned her first nesting after 18 days of incubation and the second nesting after 16 days. I don’t know the exact time the parent can feel movement of life in the egg, but she will discard one or more if broken, cracked or infertile. Let’s hope what ever she has under her is doing well so far.

Incubation exchanges occur every two to four hours. The eggs are only uncovered for a minute at most on any normal day. However, twice I have seen both parents off the eggs while chasing another falcon and a Red-tailed Hawk. The duration lasted two minutes 40 seconds for the falcon and one minute twenty seconds for the hawk. For the last week observations have been very tough due to high winds and blowing sand. By noon, I’m ready to pack it in. Gusts above 35 mph are treacherous on equipment.

Only a week or more left before the excitement begins then I will have something interesting to write about.

Those of you who follow the falcons with me can see the times of boredom and the times of sheer excitement by how often I post these little updates.

Happy trails, Bob

Item: The .33 inch of rain yesterday has had no adverse effect on the birds. Incubation continues.

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Semi-educated guess…

Observation date: 23 March 2015

Today was the tenth day in the new nest site. It is very strange to see them in this new eyrie they have never used before, although they have used it as a perch and a napping site in previous times.

Incubation has been very regular with only a few glitches. The tiercel after bringing in prey for the female has neglected to immediately return to sitting on the eggs. He has been sternly reprimanded by the female.  Once after a mid-air food exchange, he landed in the grassy hole.  This was a big mistake!  The female while still carrying the prey item dove on him, screaming vociferously and drove him back to the nest site for his turn on the eggs.  Maybe he was a bit forgetful flying on this crisp spring day.  Because he does all the hunting at this time, incubation duties are about 65% female and 35% male. By my calculations (and these are only from my daily observations) the young should hatch around April 15th. We will know for sure that the chicks have hatched when we see food go into the nest site. The parents never eat inside the eyrie, but only when they are feeding their young chicks.

peregrine, prey

Bringing in prey for the female                                            Photo by Cleve Nash

Happy trails, Bob

Item: Incubation time 31-33 days. The first sign of incubation was March 13th. Approximate fledging time is 44 days from hatching, around May 31st. Just a guess… what’s your guess?

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Switcheroo…

South side face of Morro Rock   Photo by Heather O'Connor

South side face of Morro Rock                                  Photo by Heather O’Connor

Observation date: 6 March 2015

You watch and observe for hours and hours, day after day. Just when you think you have it nailed down, everything changes. This is the case for the south side pair of falcons in nesting and choosing a nest site.

Everyone asks me “Where are they nesting this year?”

My patent reply is always, “You won’t know until she does it.”

For the previous two weeks they have been in and out of the diving board eyrie a million times. The female twice staying in the hole over an hour each time. This is what is normally seen as egg laying activity. This being the right time and an eyrie she has used nine times out of thirteen seasons. You would think…”Yeah.” Wrong again, for the last three days she has been going through the same ritual in a new eyrie, one she has never used before.  The hole is the one seen second from the right in the series of five holes in what we call the “upper five.”  Some years ago, she used the “lower five” and fledged three chicks.  That was 2011. So until I see hard incubation, my lips are sealed as to where they are nesting.

Happy trails, Bob

Item: An additional “thank you” to all who used “Amazon Smile” for holiday shopping. We received a donation of  $7.04. Every little bit counts! Remember to use the button on the right side of our website.

Item:  In the photo above, the green lines denote previous nest sites.

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On schedule…

Male and female peregrines, Morro Rock, Morro Bay, CA

Female and male peregrines                                  Photo*  by Heather O’Connor

Observation date: 25 February 2015

Breeding of the peregrine falcons continues at Morro Rock with copulations occurring every forty to fifty minutes. Occasionally, longer or shorter depending on the day’s activities, i.e. eating, hunting or chasing of other predators. Such was the case today. A large bold juvenile female made the mistake of following the tiercel back to the “rock” while he was carrying prey.  She was abruptly met by the resident female with a full-on thrust to the chest, stopping the young bird in full flight. This I had never witnessed before… a frontal attack.

Many of the observers have commented to me on how full she looks, especially in the girth. After depositing the prey, the tiercel joined in the fray. The resident female and interloper were locked talon to talon spiraling down from 75 feet above then breaking apart a few feet above water’s edge. Forty plus people watched in awe and listened to the screams as the tiercel finished off the encounter with a long chase with multiple stoops heading across the bay taking a few feathers from the young one.

The female has ceased hunting which is normal and occurs a couple weeks before egg laying begins. Other than the encounter today, her flight seems a little slower and more labored. She also perches for longer periods of time. By all the things that I observe, everything seems to be on schedule.

The next thing we will be looking for will be soiling around the vent area. This will tell us egg laying has begun.

Happy trails, Bob

Item:
She will be picking a nest site soon. When she stays in one of these holes for more than an hour or so, this is another sign that egg laying has begun. Stay tuned!

*Photo – This photo was taken with an iPhone 5 with adaptor which attaches to the Swarovski spotting scope.

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Just showing off…

Observation date: 6 February 2015

Visitors to Morro Rock today were treated with a spectacular aerial performance from the south side tiercel. Oooohs and ahhhhhs followed all his high speed acrobatics. When you think he’s about out of gas, he swerves in at great speed hitting the airbrakes to land on top of the female for seven seconds of copulation then returning to the air again. With all systems charged, he returns to speed with stiff winds blowing. In one forty three minute exercise, he copulated four times and sortied at least sixty times in front of the female, stopping twelve times for no more than thirty seconds each,  just to catch his breath. I have no idea how old this male is, but on days like this he looks to be in his prime. In previous postings, I have written about his short comings, made fun of him and called him Caspar Milquetoast, which were true, but today in gale force winds he was Caspar Studmuffin.

Happy trails, Bob

Item:
The only way for me to capture this awesome display is with words. Video and photography are extremely difficult due to the high speed of the falcon and the distance, 75 to 100 yards, and with the rock in the background. It is hard for the camera to know what to focus on. Most of the spectators see him stoop* in the blue sky and lose sight as he passes in front of the rock at tremendous speed. They then pick him up again as he clears the face to swoop up into the blue sky to make another run. These displays of speed and high “G force” turns will continue until egg laying sometime within the first two weeks of March. If you are lucky enough to see this on a windy day, I’m sure it will be etched in your mind forever.

*stoop – near vertical dive

Posted in Morro Rock, peregrine | Tagged , , , , , | 4 Comments

Questions and answers…

Occasionally our posts don’t make it through to everyone. I have changed the title and am reposting the very informative most recent post. I know that you will find it very educational. It’s just basic biology. Feel free to ask more questions anytime. ~Heather

Observation date: 22 January 2015

In the 6 hours that I observe them, breeding continues daily at about two to three times a day.  It will continue becoming more frequent as we approach the first two weeks of March.

While we’re on the subject of breeding, I receive a lot of questions, in person at the “rock,” and on the website. Here are, but a few of the most asked questions and my answers to them.

Question: Do they breed in the air?

Answer: No, they don’t. What you see in the air is normally courtship. They breed just like chickens and birds on the ground, in a tree, on a rock or in the water such as ducks. Some birds try aerial copulation such as swifts and swallows, but it is more foreplay until they get to a stable position.

Q: How do they breed? I don’t see a phallus.

A: It is called a cloacal kiss.*  The male mounts the female who is in a chin down, butt up position with both vents touching in a kiss. The male ejaculates into the female. It takes just seconds. However, ducks, geese and most water fowl have a phallus because of breeding in the water.

peregrines, cloacal kiss

A breeding pair of peregrines                                               Photo by Cleve Nash

Q: Why do falcons breed so often and for so long?

A: My understanding is that for the previous nine months, there is no sexual activity and the testes lie dormant and stay small. With all the activity they become larger and more potent.

Q: When does he know when to breed her?

A: She will usually land on one of her preferred breeding rocks and go into a submissive pose as he flies by.  If he does not get the message she will sometimes knock him off his perch and make him come to her. What a gal!

After breeding for three months, the female senses when she is heavy with eggs and she will cease all hunting activities. Within the next couple of weeks she will start laying egg and begin brooding.

Q: Does the male sit on the eggs also?

A: Yes, he does, but he is doing all the hunting to feed everyone including all the chicks. Until they are a couple of weeks old, he will brood the chicks about 35% of the time.  She will brood about 65%. At this time, the female will begin to hunt again.

I hope this might answer some of the questions that a few of you might have been too embarrassed to ask me in person.

Happy trails, Bob

Item: For the shy: Shortest copulation 2 seconds, longest copulation 19 seconds observed.

Note: I love to try to answer your questions, if I can. The answers that I have given to them are from 20 years of pure observations and have been consistent year after year. ~Bob

Sub-note: Considering the time that I have seen Bob at the “rock” over the past 4 years, his observations are very accurate and consistent. Numerous visitors to the “rock” see Bob’s dedication to precise observations of avian behavior. ~Heather

* cloacal kiss – the contact which occurs during insemination in birds when the vent of the female is everted exposing the cloacal mucosa against which the phallus of the male is pressed.  – Saunders Comprehensive Veterinary Dictionary, 3 ed.. (2007).

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May contain explicit facts of a sexual nature…

Observation date: 22 January 2015

In the 6 hours that I observe them, breeding continues daily at about two to three times a day.  It will continue becoming more frequent as we approach the first two weeks of March.

While we’re on the subject of breeding, I receive a lot of questions, in person at the “rock,” and on the website. Here are, but a few of the most asked questions and my answers to them.

Question: Do they breed in the air?

Answer: No, they don’t. What you see in the air is normally courtship. They breed just like chickens and birds on the ground, in a tree, on a rock or in the water such as ducks. Some birds try aerial copulation such as swifts and swallows, but it is more foreplay until they get to a stable position.

Q: How do they breed? I don’t see a phallus.

A: It is called a cloacal kiss.*  The male mounts the female who is in a chin down, butt up position with both vents touching in a kiss. The male ejaculates into the female. It takes just seconds. However, ducks, geese and most water fowl have a phallus because of breeding in the water.

peregrines, cloacal kiss

A breeding pair of peregrines                                               Photo by Cleve Nash

Q: Why do falcons breed so often and for so long?

A: My understanding is that for the previous nine months, there is no sexual activity and the testes lie dormant and stay small. With all the activity they become larger and more potent.

Q: When does he know when to breed her?

A: She will usually land on one of her preferred breeding rocks and go into a submissive pose as he flies by.  If he does not get the message she will sometimes knock him off his perch and make him come to her. What a gal!

After breeding for three months, the female senses when she is heavy with eggs and she will cease all hunting activities. Within the next couple of weeks she will start laying egg and begin brooding.

Q: Does the male sit on the eggs also?

A: Yes, he does, but he is doing all the hunting to feed everyone including all the chicks. Until they are a couple of weeks old, he will brood the chicks about 35% of the time.  She will brood about 65%. At this time, the female will begin to hunt again.

I hope this might answer some of the questions that a few of you might have been too embarrassed to ask me in person.

Happy trails, Bob

Item: For the shy: Shortest copulation 2 seconds, longest copulation 19 seconds observed.

Note: I love to try to answer your questions, if I can. The answers that I have given to them are from 20 years of pure observations and have been consistent year after year. ~Bob

Sub-note: Considering the time that I have seen Bob at the “rock” over the past 4 years, his observations are very accurate and consistent. Numerous visitors to the “rock” see Bob’s dedication to precise observations of avian behavior. ~Heather

* cloacal kiss – the contact which occurs during insemination in birds when the vent of the female is everted exposing the cloacal mucosa against which the phallus of the male is pressed.  – Saunders Comprehensive Veterinary Dictionary, 3 ed.. (2007).

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2015: Breeding season begins…

Observation date: 7 January 2015

This is the 9th, an hour after proof reading the January 7th Pacific Coast Peregrine Watch posting this morning. I left for the “rock.” At 9:05AM arriving at the “rock” I’m setting up my gear, meanwhile one of my cronies pulls up and says, “I see you have the female on the “chimney.”

I answered, “I haven’t had a chance to look. I’m still setting up.”

At 9:23 AM, I hear my crony, Gordon, voice again, “She’s getting bred.”

Sure enough right on top of the chimney and I don’t have my camera set up. I stayed until 4:45PM with 400mm lens and camera set for video, prefocused on the current boudoir, but to no avail. Seven hours and no second breeding.

Tomorrow I’ll set up once again without the chin whiskers, but knowing at least they have started the breeding season for 2015.

Bob Isenberg, Pacific Coast Peregrine Watch

Bob Isenberg                         Photo By Heather O’Connor

Happy trails, Bob

Item: Copulation 9:23AM, duration 9 seconds. (and retires to the diving board for a cigarette for a smoke.)

Posted in falcon, Morro Rock, peregrine | Tagged , , , | 4 Comments