Monday, February 10th, first breeding observed today at 11:30 AM on a sunlight rock. After a month of watching and waiting, I wasn’t sure they were ever going to have young this year. In all the years I have observed these birds, they have always started breeding the first week of January without fail. Last year the 7th of January, the year before that the 4th of January. The north side pair have been spending a lot of time around the “bowling ball” eyrie she had nested there three years ago. And this is my guess for this year, but you never know.
I have no answer for the late breeding only that wildlife knows something that we don’t. I’ll keep you informed.
I know our last posting had some dismal news regarding our Peregrine Falcons at Morro Rock. We were getting concerned that we would be making a lot of excuses at the 2025 Morro Bay Winter Bird Festival, January 16th through the 20th. However, on January 15th, we had a very good day sighting both male and female falcons flying and perching for extended periods. That lifted our spirits.
Our site at the Festival was a “Stop and Scope” affair. We set up four scopes and lots of chairs for people to stay and view as long as they wished. Our birds did not disappoint. Both of them showing up multiple times each day.
At times , we had as many as six scopes and two cameras set up. We welcomed as many as five tour groups each of the four days as well as the general public which totaled 100-150 viewers per day.
As you might imagine, between setting up, tearing down, setting and re-setting scopes as the birds changed perches throughout the day and talking to so many people, we were exhausted by the end of the Festival.
We are now back to our regular schedule, ten to two o’clock, with both falcons gracing us with their presence daily. What we have not seen yet is the breeding, which at this point is about two weeks later than in past years. They could be breeding somewhere else out of our visual field. We are seeing them for extended periods and would likely see some “action.”
Jerry Pyle and Bob Isenberg on normal duty
That’s it for now. Observations contributed by Jerry Pyle.
For the last couple of months nothing has been going right in many ways as in years past.
We have been skunked five out of seven days every week. Only an occasional fly-by and no landings. The tiercel has been AWOL for the last ten days. Normally, we would have seen bonding, courtship by this time of the year. We have seen reports of sightings around the Morro Bay estuary, but not the Rock. Very slim. Jerry and I are still here every day! We pass the time with our spotting scopes on sea otters, birds on the sand spit south of us, birds perched on the three stacks, etc.
Sorry I don’t have more. Sad! But we do have a celebration of Morro Bay holidays in the local style with our decorative, nautical Christmas tree of crab pots and buoy markers.
After a week of egg laying, today we saw the first signs of hard incubation. As we arrived on the south side of Morro Rock, 10 AM and only the male falcon was visible, high up on the edge of an arrowhead shaped hole about 10 yards from the nest site. Around 11AM we heard chupping from the nest site. The female then came out of the eyrie and flew to a rock about 100 yards east where the male quickly copulated with her and then flew into the nest site. All of this in about 45 seconds.
He remained in the nest site for an hour and ten minutes. This continued on for the rest of the day. The female staying in for two hours or more at a time. He sits on the nest for half as long as she does. This is normal behavior since the female does not hunt. He must find food and bring prey to her.
Watching the activities of north and South side falcons, egg laying is underway for the last few days. The female stays in the “diving board” hole for an hour or two then out for the rest of the day. The Northside female visits both the “cathedral and “bowling ball” holes, so we won’t know until all eggs are laid and she starts incubating. If our observations are close, hatching should occur around the third week of April.
Below is a map of the south side frequently used holes for nesting, perching and stashes.
This past week we met with our most recent CalPoly Scholarship student, Eva Moylan. We’d like to introduce her to you. All of your donations made this possible!THANK YOU!
Eva Moylan with male American Kestrel
Eva told us this bit of information:
“I am currently going into my fourth year in Biological Science at Cal Poly and for the past few years I have been part of the Francis Ecology Lab, which focuses on evolutionary ecology, community ecology and conservation. Since 2021, I have been involved in the Black Oystercatcher Monitoring Project in SLO County. This project was originally a 10-year, Audubon funded, citizen science study with the goal of collecting nest monitoring data on Black Oystercatcher reproductive success along the West Coast. Locally, the project was taken over from California State Parks by Cal Poly in 2022, and we are continuing breeding season monitoring efforts. Additionally, we have begun incorporating telephoto imaging of Black Oystercatcher eyes to discern if pupil irregularities can be used to identify individuals since our local population isn’t banded.
Another ongoing project in this lab involves visiting museum skeleton collections to take orbital, sclerotic ring, and tarsus measurements to calculate light-gathering ability of the eye. These data are used to determine how different species may be evolving over time in response to increasing light pollution. Two other students and I visited Berkeley’s Museum of Invertebrate Zoology this August to get measurements for species not currently in the dataset and we are looking forward to visiting the Museum of Natural History in Los Angeles later next week.
This summer through the Frost Summer Undergraduate Research Program, I’ve had the opportunity to work on a project using MAPS banding station data with Dr. Clinton Francis and Dr. Sarah Jennings. This dataset currently includes North American bird capture data spanning from 1989-2018 and our goal is to determine if species-specific productivity and abundance trends can be connected to environmental change across the continent. I’m excited to continue working on this project as a senior project! Additionally, this summer I was able to volunteer the Powell II MAPS banding station in Los Osos. I gained experience using mist nets and handling birds as well as learning what and how data are taken during this process. I loved being involved in a bird banding station and will definitely be looking into internships in this field after graduation to gain more experience!
Bob Isenberg and Eva Moylan at Morro Rock
From a young age, scientific illustration has played a large role in my interest in birds so I hope to incorporate it into my future career as well. When I began my undergraduate degree in 2020, I was interested in pursuing scientific illustration after graduating with a B.S. in biology. As I have become involved in ornithological research within the past couple of years, I have developed a love for scientific inquiry and the process of investigating new questions so my main goal for the future is to pursue a research career in avian behavior and conservation. However, I am inspired by the connection between science and art and I would love to find a way to incorporate research, illustration and science communication where I can also continuously learn from others. I am so grateful for the opportunities I have been given through Cal Poly and the Francis Ecology Lab to discover my interests and gain experience in this field, and also to organizations that support biological science students like the Pacific Coast Peregrine Watch!”
Come see us out at Morro Rock, Morro Bay, CA , USA. Bob is there between 10AM and 2PM every day.
A while back I contacted our five CalPoly Scholarship students to hear how they were doing. They all replied despite their very busy lives. I’m sure you are curious so I’ll catch you up on two of them.
Waverly Davis wrote that she was about to board a plane for South America in about an hour. She traveled with her sister for a few weeks in Ecuador and Peru and excitedly packed her binoculars hoping to see some of the “awesome South American birds!” She “worked on various research projects and seasonally monitored watersheds in Colorado, Utah and Arizona.” Her enthusiasm was clear that she “wanted to see those areas restored to their former glory one day.” In 2021 she went back to a previous job working with the CalPoly Sensory Ecology lab on a project in New Mexico. That year she “was in a managerial position and enjoyed seeing the project she’d worked on as a field technician from a different perspective.” She also “had so much fun measuring and banding birds as well as nest searching.”
Alon Averbuj wrote in 2021 that he “just finished up a year of work in Hawaii studying endangered birds.” He was an AmeriCorp Service Member at the Kauai Forest Bird Recovery Project where we studied and conserved two species of Hawaiian honeycreepers, and one species of thrush. It was a wonderful year of intense field work, amazing friends, and beautiful birds. He is “now back on the mainland applying for ecology PhD programs.”
I can tell I’d better get in touch with our CalPoly Scholarship Students again to get the latest news! It’s been a while. Life moves so quickly and goals are accomplished! Onward to the next goal.
Your DONATIONS have made this and more possible! THANK YOU to all of you who donated!
Alon Averbuj working on his Kauai Forest Bird Recovery Project.
Arriving at Morro Rock this morning, the one single chick on the north side the Rock was already airborne. Flying low and slow, we thought it might just be another bird.We had not expected the chick to fly for another week. When he landed we found him in a long strip of green brush with gull nests above and below him.
The magnified chick can be found in the lower right corner. Photo by Jim Twentyman
The adult female kept flying over and diving on him trying to get him to fly. With no luck, she then brought a bird to eat, which he did. Tomorrow we will be further to the south end of the north face of Morro Rock where all the chicks from the past seem to gather . It’s called the nursery.
Bob Isenberg in the light blue jacket, Jerry Pyle in the dark blue jacket at Morro Rock, Morro Bay, California.
Here are just a few updates on the falcons we have been watching on the north side of Morro Rock. We have moved our location and set-up of spotting scopes and chairs over to the surfer side of the parking lot to better observe the nest site. It is called the “bowling ball” nest. There are three holes that look like a grip with two holes below and a thumb hole above. By our observations, the chicks hatched about three days ago, the 14th of April 2023. We believe this because that was the day we first saw food go into the nest site.
Today, the male brought in two birds both within two hours. These were both mid-air transfers, male to female. Nothing is visible at the nest site. However we should see young chicks in about two weeks or so. If our calculations are close, the chicks should fledge around the week of the 27th of May. It’s an exciting time to watch the young and it’s free!
Happy trails, Bob
Item: Most everyone at the Rock placed their bets on “four” chicks. I’ll be safe and say “three.”
Pacific Coast Peregrine Watch has experienced a temporary set back due to the absence of Bob Isenberg.
I have undergone back surgery and am recuperating doing lots of rehabilitation at Bayside Care Center in Morro Bay, CA. Not to fear the Peregrine Falcons are in good hands with my buddy, Jerry Pyle, who is providing the spotting scopes and information.
The birds are beginning to nest now. Both pairs north and south have begun selecting nest sites in the last two weeks. Normal progression for this time of year is egg laying in the middle of April. Hatching will be thirty one to thirty three days later. Forty four days to fledging from day of hatching. In other words by the first of June, you should see young falcons flying.
Look for Jerry and the spotting scopes. On windy days you might not see Jerry or may find him on the south side of Morro Rock.
South side of Morro Rock-During breeding season through fledging: Late December-July. (Sometimes the CA State Parks closes the gate and makes it impossible to take Bob's truck out to set up during the winter. Call first.)
If you wish to find Bob Isenberg check the north side of Morro Rock, where he photographs surfers many mornings.
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