Nest Followup Visits, The Raptor Center at the University of Minnesota

The Great Horned Owl Nest: Follow-up Visits
By Barb and Herb Draeger

April 23, 1995
Time: 9:15 a.m
Weather:
Temp: 42
Wind: Calm 0 to 15 MPH
Sky: Sunny
Both chicks are in the reconstructed nest, standing and exercising their wings. Have sighted the female owl four trees away. After five minutes, she flew toward the backside of old growth trees lining the field. She's nearly hidden by branches of the oak and elm trees in this stand of trees.

As the parent is near the new nest, no search for evidence of pellets is necessary. Herb and I will observe from a distance to assure their security. Contact with humans during the rescue was kept to a minimum to insure the chicks did not became imprinted during the time they were out of the nest. Other raptor chicks have been out of their nests for examination as long as 45 minutes without becoming imprinted to humans. The reasons for these exams was only for monitoring birds being reestablished and the information was vital for their survival. Young birds only become imprinted when a human provides food, water and shelter for extended periods of time.

April 28, 1995
Time: 2:30 p.m.
Weather:
Temp: 38 to 61
Wind: East 5 to 12 MPH
Sky: Partly Cloudy
Viewed the owl chicks from the road. The oldest was "branching" to the right side of the nest, the youngest was tucked into the nest. Decided to walk into the field for a photo opportunity. The chicks cooperated by not changing positions while we (my husband and I) walked in.

My husband took several good poses of the branched owlet. The youngest stayed partially hidden in the nest. The older has little or no shafting left on its feathers. At this date the chicks should be over 25 days old. They should leave the nest at about 35 to 45 days after hatching. I found several pellets below the nest, packing them carefully away, we then hiked back to the car.

April 29, 1995
Time: 10:30 a.m.
Weather:
Temp: 48
Wind: 0 to 8 MPH
Sky: Overcast, rain due
Our daughter Valerie wanted to see the baby owls before they leave the nest, all three of us hiked into the area. Upon coming over a ridge near pond one we spotted two people in a canoe powered by a small electric motor fishing in pond one. This entire area is owned by the gravel pit and unauthorized persons are not welcome. By citizens band radio I notified the crew chief about the trespassers. The three of us hid behind a low line of bushes to wait until the people in the boat were evicted as we did not wish to attract attention to the owl nest.

While we were waiting, two more persons hiked to the shore of the pond with fishing equipment. As the crew chief had not arrived, radio contact was again made informing him of the additional people here. The gravel company has many problems with trespassers. The pond is very dangerous as water from other areas is pumped into it at high pressure causing undertows and swirling eddies.

The two hikers have spotted us and are attempting to depart, but Craig, the crew chief has arrived detaining the hikers, then expelling them. The two people in the boat have refused to leave, and as Craig has no boat, there is little he can do. To avoid the boaters seeing us as we moved toward the nest by hiking deeper into the edge of the woods and will approach from behind the line of trees.

At first we saw only one chick, five blue jays noisily hinted that perhaps the parent owl was nearby. We took several photos before we decided to explore the field surrounding this area hoping to discover the reason for the jays¿ distress calls. While searching the trees with binoculars, we spotted a hawk, medium in size, slightly rounded body, long tail, colors hard to tell outlined against the sky. It may be a goshawk.

There are Indian burial mounds here and we move around them being careful to not disturb them in anyway as we explore. The area we are in was once a large Indian encampment, many burial mounds are scattered throughout the sight. Nearby, Herb has found a wide deep hole that is littered with walnut shells and other nut shells hinting that this hole is from a ground squirrel or other nut eating mammal. The strong odor of skunk drifts in the air too, making us cautious.

On returning to the nest area, we saw the second owlet as it peeked over the edge of the nest, then snuggled close to its nest-mate as it returned to the nest. Several more photos were taken of the two chicks before we left the area at 2 p.m.

May 3, 1995
Weather:
Temp: 60
Sky: Overcast
Wind: 0 to 7 MPH
Have again hiked to the area under the nest. By using the shelter of the tree, observation of the owl chicks is quite easy. They don't seem frightened by the visits as any approach to the nest is made quietly and with little disturbance.

One chick has moved to the right side of the nest. I can see this chick is fully feathered without any shafting visible on the feathers. The second chick is not within my view, possibly tucked down into the center of the nest. The adult is sitting in a nearby oak about 20 feet lower than the nest.
There is little activity from the three birds, but I can tell the chick that can be clearly seen will be ready to fly within the next week or two. The second chick is still not visible.

May 11, 1995
Walked to the nest after checking to see if the parent bird or chicks were visible. One chick was branched to the left of the nest and the second was perching less than 25 feet from the original nest. This second chick is the larger of the two young birds, it seems very healthy and somewhat prouder after its first flight to independence. The chick seems very calm and not frightened by my presence directly below his branch as I move quietly around to collect any pellets, checking for freshness and content.

One of the three pellets gathered is still damp, the contents reveal the remains of a bird. There are yellow and blue-gray feathers, along with an undigested foot, wing bones and part of a birds skull giving indication of a small bird. The color of the feathers hint the prey was a Yellow Warbler, several groups are known to frequent this area.

The other pellets seemed hours older. One contained the remains of a small rodent, with the front teeth left intact along with the front part of the rodents head, there are bits of fur, indistinct in color and some leg bones joined at the hip socket with part of the spine attached. The third pellet contained black feathers, longer wing bones than the Warbler, part of a birds lower leg and other bones indicating remains of a crow or a blackbird.

After inspecting the first three pellets, I returned to the area under the nest and found the second chick just watching as the pellets were collected. The next pellet was very large and contained parts of soft, long fur, tan-brown in color, a leg joint from a hock section or knee section, and a part of a rib cage. These parts from their large size hint that this prey was a rabbit. I stayed to observe for a while longer, deciding to return on Saturday with camera in my pack.

May 13, 1995
Weather:
Temp : in the 70s
Wind: 0-12 MPH
Sky: Partly cloudy
Both chicks are now well away from the nest. One is sitting slightly above and to the left of the first chick, the second is below and to the right . One thing of note is that just below the second chick is the leg of what appears to be the leg of a young gosling jammed into a crevice of the tree where they are perched. After looking thoroughly around the area below, my husband and I were unable to locate any other parts of the gosling, we will search below the other perching sites used by the adult to see if we can find anything.

Herb took many pictures as I searched the field and other perching sights without success. It's possible that the gosling leg was brought from another part of the gravel pit. The bat pellet I found and abandoned weeks earlier is still where I left it, but there are other pellets to be gathered today from the area to be saved for examining later.

Out of curiosity, Herb and I again explored an area around the Indian mounds just 50 feet away. Some of the mounds are flattened long ovals, others are rounded and 4 to 5 feet high. All are overgrown with local plants and vegetation. We will not disturb this sacred area and are hiking out to the road.

Postscript:
Herb and I made several more journeys into this field after the chicks moved to a different tree and were able to see them several more times over the next two weeks. After the first week in June, we were no longer able to locate either the chicks or the adult. Because we were able to watch them up to that date, and able to observe their general well being, we believe that they are well on the way to becoming good hunters.


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Last modified on Friday Jun 25, 2004

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