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Baby Season
A Year to Endear

A story about the year 1997. This provides an
interesting insight into a year of raptor rehabilitation.
Baby season was quite
something this year -- for one thing, five of our education birds
laid eggs for the first time... ever! Including our 9 year old
great-horned owl, our 11 year old red-tailed hawk, a kestrel, screech owl,
and barn owl. With most of them, there was not a chance of their being
fertile, but having the birds go through part of the breeding cycle
provides an opportunity to use them as foster parents. Oddly enough, in
captivity, it is more often males that are good foster parents, not
females.
The leader of the pack was Burwell, a great horned owl ("GHO"). Last
year, she had made a couple of scrapes in the gravel bottom of her cage -
and I had actually put in a hollow bark ring as a potential 'nest' - but
nothing had happened. This year, I saw her starting the scrapes and just
shrugged... and then suddenly realized she had been sitting in one place
for a full 24 hours. Sure enough! When I peeked under her, there was an
egg. Four days later she laid another! (For some reason, with the four
birds that laid at least 2 eggs apiece, all of them had a period of about
4 days between the first one and the second.) I was excited! Now Burwell,
a human imprint, will not tolerate anyone but me in her enclosure at the
best of times... now I became her mate in earnest, bringing food directly
to her in the nest - and then leaving very quickly before she charged me!
S he had laid the first egg on February 26th - great horneds are notorious
for nesting very early, probably because their off-spring have a very long
post fledging dependency period, with a lot to master before they are on
their own. I let her sit on the eggs through March, well past a normal
incubation period, and just as I was thinking of removing them, I got a
call from Roseburg - fellow 'rehabbers' there had just gotten in a
nestling GHO that they were unable to return to the nest. (They also
brought up a nestling barn owl, as our male barn owl is a fantastic foster
parent every year - but that's another story!)
Now the fun begins! They brought the owl up the next day - April 5th. Not
knowing how the introduction was going to go, I fed the baby a small
amount, then put her into a carrier and moved her into Burwell's flight.
Letting them see each other for awhile, I noted that the baby was frantic
to get to what she recognized as a 'Mom' - and that Burwell, though not
leaving her eggs, was not reacting in any hostile manner. So - holding my
breath - I reached under Burwell, while she was focused on the baby, and
just as I opened the door to the carrier, I removed the eggs, without
letting Burwell see them. Still keeping the carrier door between the baby
and the adult, I watched again for hostility and then, while still
standing close by, I handed Burwell some food and let the baby have access
to the adult. Talk about love at first sight! The baby made a beeline for
Burwell, grabbing at the food in her beak. I was nearly dying with
(silent) laughter as the adult tried to do several things at once: stay
brooding on the eggs she didn't know I'd stolen, protect her eyes from the
baby's grabbing beak, and greet the baby with food. This last was the
hardest - Burwell had the instruction manual somewhere in her genes but
this was definitely her first trial run, and I had messed up the equation.
Instead of the helpless, just hatched newbies she would normally be
feeding, I'd slipped in a month-old one pound ringer who was more
experienced at this feeding business than SHE was. The baby wasn't old
enough to tear up food, but neither did she need to be fed tiny tidbits...
Finally, the two worked it out, the baby was fed, tired, and wanted to go
to sleep. She was leaning against Burwell's breast, who (still in brooding
mode) tried really hard to push down on the baby with her 'chin' while
pulling her in with a wing... trying desperately to get that way-too-large
bundle of fluff UNDER her where she was supposed to be! Again, tears of
laughter on my part. Burwell finally compromised by tucking the baby under
one wing - and both of them had a nap.
Now Burwell's cage is on public display, so we hung screens all around the
nest to keep human exposure to a minimum. I didn't want to move the pair
out of that familiar cage until the baby had 'branched' (left the nest),
which didn't happen until April 15th. By the 18th, the baby was able to
get up on a high perch - so I moved them both to a rehabilitation cage.
Shortly after, two more fledglings came in, and Burwell took them also
under her wing (this time figuratively, as they were way too old to need
brooding!) On June 2nd, after a little bit of live prey training (in which
Burwell embarrassed me no end by trying to show the babies how to catch
mice on FOOT and with her BEAK!), all three were hacked out on the
property. We knew they would stick around, because 'Mom" was there, and we
set up a feeding platform on the outside of Burwell's cage. During the
summer, they have all taken turns disappearing for days, even weeks, at a
time; currently one male has apparently truly dispersed, as he's only been
back once in the last 7 weeks; the other two take turns going off for a
week or two at a time.
(Editor's Note: Burwell died in 2004 at the age of 16.)
We didn't get any young red-tails in time to try Tomahawk with an orphan.
I came back from teaching a class in Idaho, walked into her cage on March
26th and found a broken egg on the ground. I admit it took me a minute to
figure out that it had to have come from the hawk... but when I did, I
grabbed a heron nest I had lying around and placed it on her feeding
platform. She immediately took up housekeeping; I cut her some evergreen
bows, which she carefully arranged. She laid her second egg in the nest on
March 30th, but didn't start incubating until she laid the 3rd on April
2nd. I finally pulled her eggs May 13th, after about 40 days - much to her
relief, I believe! I had been feeding her on the nest and she would get up
and stretch (I think I was supposed to take over for awhile, but what do I
know?) At any rate, she had been leaving the nest for longer and longer.
We got one young red-tail nestling in on the 25th of May and were able to
return that to the nest, thanks to help from Longbranch Tree Service. We
got another, older nestling in on the 7th of June and tried to introduce
it to Tomahawk, but she was no longer in the mood! That one and one other
we had to raise ourselves! This was a strange year for red-tails. We were
getting a number of calls about screaming youngsters in the nest, or
fledged and on the ground, but with parents still around. One of these
situations was really a mystery.
We'd been called by a concerned person about persistent screaming from a
nest that she'd been watching from the time the parents built it before
the tree had leafed out; the caller hadn't seen an adult in several days.
Another call to Longbranch, and as they and I pulled in the driveway, here
comes an adult! Relief all around! (Longbranch really hadn't wanted to
climb that huge old cottonwood!) However, a few days later, we get called
again by other residents of that same apartment complex - a screaming
youngster on the ground, unable to fly; another one on the roof-top. We
pick up the one that isn't flying: extremely emaciated and weak, despite
the presence of his parents.
This bird was fully and perfectly feathered; whatever malnourishment had
occurred, had happened after feather development, as there was not a mark
on his feathers. He was extremely anemic (9% red blood cells, where 35-50%
is normal) and his serum protein indicated that he had not eaten for days.
I have always believed that our best option in these cases is a blood
transfusion, though sometimes, as was the case with this one, not even
that can save them. He died shortly after we returned from the vet. Five
days later, after a few unsuccessful attempts, we got hold of his sibling.
Again, a parent was flying overhead, but the bird was on the ground,
screaming, extremely emaciated and weak; this one, being down even longer,
had 7% red blood cells in circulation and essentially no total solids in
his blood at all.
Since a transfusion had not worked for his nestmate, this time I tried a
protocol used by a long-time friend in Wisconsin. I started with very
dilute solution of meat baby food and Pedialyte, gradually increasing the
proportion of meat. Although he lost weight initially, his blood values
improved steadily. Within four days I was hand-feeding him chopped up
whole food; within 2 weeks he had gained almost a pound. We were able to
release him at the end of July. I have no idea if the parents were just
not able to find food; if they had been gone for awhile, if one of them
had been killed.
What was odd was that I was hearing similar stories of screaming
fledglings from many different parts of the country; no explanation, but
one theory was that the spring floods may have destroyed the first nest
attempts of prey species. Though the adult rodents survived, their
off-spring, who would have been having young of their own to coincide with
young raptors leaving the nests, did not. So though there was no shortage
in the early nesting period, there was a shortage of food later. Just a
theory.
We also had a record year for Coopers hawks! One nest came in when a large
branch broke off a tree; the babies were just hatchlings. So young, in
fact, that we could not definitively identify them - beyond the fact that
we knew they were diurnal raptors, too small for eagles, definitely not
falcons... not ground nesting, so not harriers. The accipiter foot was not
apparent for several days, by which time they were growing so fast, we
entertained a brief flurry of concern that they might be goshawks. But
Coopers they were - despite an early identity crisis while they were being
fed with a red-tailed hawk puppet...! We could not return them to even a
substitute nest because we did not know where the nest tree had been -
despite several messages, the finders did not call us back.
We can do the best job a human can do raising orphans - in effect, feeding
them well and teaching them how to hunt rodents, perhaps, but we still
can't come close to what their natural parents can teach them. We were
able to find a falconer in Corvallis to take over their tutelage at
fledging age - the best option, since Coopers hawks are designed for
bird-hunting through dense cover, which is not a situation easily
duplicated in a flight cage! We were able to return another nest-full of
Coopers hawks to the tree from which it came - and have both parents in
full attendance almost immediately. Another Coopers nestling came to us
from eastern Oregon, in the aftermath of a wildfire. This one we placed in
a hack box on our property as a nestling; fed her there for some time;
then opened the box to coincide with her fledging. She returned to the box
for food as she learned to hunt on her own. We spotted her at the bird
feeders (!) and the hack box for some time. Other older fledglings came in
- all in all, we received and released 11 Coopers hawks so far this year,
a quarter of all those we've seen in the last 10 years!
The limitations of captive-rearing of raptors were never more evident than
when we were presented with a nestling osprey in late July! This had been
an osprey summer - we'd received 8, when we usually see only 1 or 2 a
year - but this one was really a challenge! The Forest Service quickly
found the nest from which he'd taken a dive - the baby had been found in
the middle of the road, having fallen probably 165 feet. He must have
bounced off just about every branch on the way down, since he didn't break
anything, despite not having enough feathers to even slow him down!
Unfortunately, this was a very big (6' diameter at breast height) tree,
with the top 40' very dead and unclimbable; Tim Brown, master tree climber
from Seattle, generously made an attempt to put up a substitute nest on a
lower branch - an questionable proposition, anyway, as we didn't now if
the parents would tend two nests. But the bark was dying and just
splintering as Tim tried to find footholds. There were no other nests that
we heard of, despite emails throughout the Forest Service network - all
the other nests that anyone had been monitoring had already fledged their
young.
This nest - obviously a second attempt, given the late date - still had
two other nestlings in it, judged to be about 4 or 5 days older than the
one that fell. We considered putting the baby in an unused osprey nest at
Fern Ridge Reservoir as a hack site, but we would have needed to feed him
probably twice a day (and would have needed a lift-truck to get to the
nest each time!), and he'd have no parent to protect him from hot, wet, or
cold weather or crows, ravens, GHO's, or whatever else might be attracted
to him. After discussions with osprey folks around the country, we decided
our best option was to wait until his two siblings fledged, then put this
one up in a nearby tree. At that point, the parents are more programmed to
feed any calling youngsters, and are not necessarily so focused on the
nest site itself.
The Oakridge Forest Service biologists (who were incredibly caring and
helpful throughout - in fact, we could not have done any of this without
them!) monitored the nest, picked a nearby tree to put a nest platform in,
and built a platform to Tim's specifications. Tim and USFS biologists felt
the original tree's seasons were numbered, given its condition, and that
by putting up a substitute platform now, the osprey pair would have an
alternative nest site. The osprey siblings fledged, of course, when Tim
was tied up, but within two days, he drove down again from Seattle,
climbed the tree, established the platform, hauled up the baby, took lots
of pictures, and came down again.
We could only cross our fingers and pray, as the nestling we had was now
at fledging age himself and thus not guaranteed to stay on the platform
for any length of time. The main drawback was that he had not had the
hours of practice on the edge of the nest that his siblings had (next time
I'll build an elevated platform, as he had shown no inclination to flap
while I had him) and I was concerned that he wouldn't be able to maneuvre
those incredibly heavy, long wings well enough to get up and over to the
original nest, where the adults were still serving meals to their fledged
youngsters. The baby definitely started his flight practice the minute he
was on the nest... nothing like being 120' up in the air to give you room
to FLAP!
The adult ospreys were definitely in attendance and started to hover
between the two nests as soon as Tim was down the tree. By the next day,
the baby was gone, but the biologist monitoring the nest was sure he had
heard three youngsters calling each time he went to the site - though the
two he saw at the original nest the day he brought his spotting scope were
not banded. I hate these cliff-hangers, but I can truly say that this was
his best option for this bird. I mean, how was I going to teach this guy
how to snag fish? Much better that he get the chance to observe experts -
his own parents! - who were also programmed to feed him while he was
learning. We can only hope that we get a postcard from Baja California
some winter... or eventually find a banded adult nesting in the area! It
was definitely a delight to hear him calling to the adults, despite his
more than 3 weeks in captive care.
This doesn't mention the kestrel babies, the screech owls, or the
green-backed herons we got to host... but we had a particularly busy baby
season this year. Getting in something like two birds a day throughout
June, rather than our average one every two days, was definitely a
challenge. But we love a challenge... and it was never so obvious as, just
as we released the last of the screech owls which had come in as orphans,
we started to get in the fledgling screeches that were injured in their
first foray into independence. Definitely a year to remember! My sincere
thanks to our outstanding crew of volunteers who helped me keep everybody
straight and shared all the responsibilities so graciously.
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