On January 19, 2007, I had an extended encounter with a pair of
Ivory-billed Woodpeckers in the Choctawhatchee River in Florida and obtained video footage of
several events that can only be explained in terms of that species.
I was following up on a report of a pair the previous day along with several members of Geoff Hill’s search team.
The encounter began at 7:25 a.m. as I kayaked
around a bend in a small bayou and saw two large birds repeatedly
making spectacular swooping flights in the distant treetops. This behavior is consistent with historical accounts of
the Ivory-billed Woodpecker. A high-definition video camera was
mounted on the kayak paddles. Due to blockage in the bayou,
it was not possible to move closer in the kayak. I decided to remain in the kayak rather than risk
flushing the birds (as happened when the observer attempted to approach the birds the previous day). I laid the paddle-cam
setup in my lap with the camera aimed in the direction of
the birds while watching the movements of the birds. During one of the flights, I had a good view through
binoculars of the dorsal surface of the right wing. The wing was fixed during the swoop, and a white trailing
edge that extended nearly to the tip of the wing was clearly seen. Ivory-billed Woodpecker is the only candidate species
with this pattern on the wings. The camera captured several events involving highly unusual flights and other behaviors
that are consistent with the
Ivory-billed Woodpecker but do not seem to be consistent with any other candidate species. Field marks consistent with the
Ivory-billed Woodpecker appear in some of the events. The 2007 video is discussed below and in this lecture.
The encounter lasted for more than 25 minutes, and the camera captured the following events
within a nearly continuous stream of video (a brief interruption to report the sighting by radio preceded the final event)
while it was kept aimed in the same general direction:
The events from the video are presented in temporal order below. The
context version of the video (which contains the first 13 minutes in reduced resolution) documents me
repeatedly maneuvering the kayak to remain in an observation position and then
deliberately aiming the camera after getting out of the kayak. I was observing with binoculars, and the camera
occasionally rotated forward and pointed down into the kayak. At 5:21 in the context movie, I can be heard whispering
to three deer in an attempt to prevent them from getting
spooked and scaring off the birds. After 7:20, they can be seen moving toward the area where the
birds had been swooping around in the treetops. There were two Pileated Woodpeckers in the area that
morning. One of them can be heard calling at 8:20. The camera captured dialogue with Bob O’Brien, one of several
members of the search team in the Choctawhatchee that fanned out around the area of the report from the previous day.
He kayaked along the same bayou and arrived 16:22 into the video. In these
verbal field notes, I told Bob about the swooping behavior, the white trailing edge,
and the fact that there was more than one bird (two birds appear simultaneously in part of the video).
- Flights beginning with swooping takeoffs occurred at 2:02, 3:18, and 24:37. During the first event, the mostly white
underwings are consistent with Ivory-billed Woodpecker, and the combination of a swooping takeoff followed by a long
horizontal glide is not consistent with any other candidate species but matches the following account by Audubon: “The
transit from one
tree to another, even should the distance be as much as a
hundred yards, is performed by a single sweep, and the bird appears as if merely swinging from the top of the one tree
to that of the other, forming an elegantly curved
After the takeoff at 24:37, there was a change in the flight path that could have been a reaction to a noise, and the
landing was also captured in the video. The takeoff at 3:18 was immediately preceded by an upward swooping landing.
- Swooping landings in which the bird ascends nearly vertically occurred at 3:18, 5:10, 5:44, 15:21, and 24:37. The
landing at 5:10 was captured in its entirety, starting before the bird began to ascend. The highly unusual long vertical
ascent is not consistent with any other candidate species, but Audubon may have had such a maneuver in mind when he mentioned
that “the flight of this bird is graceful in the extreme.” In multiple frames during the ascent, it is clear that
the body (including the belly) is black and the right underwing is mostly white. These markings rule out all candidate
species except the two large woodpeckers, but the maneuver and the amount of white that appears earlier on the dorsal
surface of the right wing are inconsistent with Pileated Woodpecker. The landing at 5:44 could be the bird that appears
in another event less than 10 seconds earlier. During the landing at 15:21, the underwings appear mostly white, and the
bird apparently rotated about 90 degress about its main axis while ascending. Woodpeckers typically swoop upward a short
distance and then land on the side of a tree that faces the direction of approach. Making a long vertical ascent opens up
the possibility of rotating about the main axis and landing on a surface that faces in any direction. During the landing
at 24:37, there was apparently a similar rotation, and the dark belly, light-colored underwings, and shapes of the tail
and wings are consistent with Ivory-billed Woodpecker. While the bird is climbing after the landing, there are several
prominent flashes of white that are consistent with the white triangular patch on the folded wings of an Ivory-billed
- The deep and rapid flaps during a level takeoff at 5:36 are not consistent with any other candidate species, but
they are consistent with historical accounts of the Ivory-billed
to Tanner, the Ivory-billed Woodpecker has “particularly hard”
flaps at takeoff that are louder than the flaps of any other species he had heard of that size besides a grouse. According
to Christy, the wings are flapped at takeoff with “deep and rapid strokes after the manner of a crow or duck.”
The deep and rapid flaps are also consistent with the sound of rapid flaps at takeoff in the historical film of an
Ivory-billed Woodpecker and with the deep and rapid flaps at takeoff of the closely-related Imperial Woodpecker. According
to all of the existing evidence, the Ivory-billed Woodpecker takes
off with a much higher flap rate than the Pileated Woodpecker. In this regard, the difference between these species is
similar to the difference between another pair of superficially similar species, the Loggerhead
Shrike and Northern Mockingbird.
- Starting at 17:37, the camera captured a continuous series of events involving a woodpecker that has markings consistent
with Ivory-billed Woodpecker and multiple behaviors that would each be difficult to explain in terms of any other candidate
species. After taking a short flight, the bird climbs upward, moves to the right, moves back to the left, perches, delivers
a blow, takes off with deep and rapid flaps, and swoops upward. A loud knock can be heard just after the blow (the slight
delay is apparently due to the distance to the bird). According to Tanner, the Ivory-billed Woodpecker uses single and
double knocks as signals, but this behavior does not seem to be consistent with any other candidate species.
Other woodpeckers are known to give isolated knocks during drumming, but there was no drumming either before or after the
knock. Woodpeckers typically listen for a response after drumming, but the bird took off
immediately after delivering the blow. At two points during the event, the bird perched on its tail and rotated its body
from side to side. Multiple occurrences of this behavior at two locations within about 20 seconds does not seem to be
consistent with other woodpeckers, but Ivory-billed Woodpeckers in the historical film make these motions nearly constantly,
with about the same angle and speed of rotation as in the video. The bird flailed its wings several times just before the
double knock. Multiple occurrences of this behavior within about 5 seconds would seem to be unusual for other woodpeckers,
but it would make sense for a massive woodpecker that is trying to keep its balance, and it occurs in the only known
footage of the closely-related Imperial Woodpecker.
At 2:02, there was a
swooping takeoff (movie plays at half speed).
The beginning of the takeoff
appears in the upper right of the picture. The bird is hidden behind vegetation during part of the swoop,
but it comes back into view in the lower left of the picture. When the bird briefly comes back into view
further to the left (movie plays at half speed), it is still moving at high
speed and the underwings appear white in the reflection from the water, which is consistent with
Ivory-billed Woodpecker. The swooping takeoff and long horizontal glide are consistent with
Audubon’s account. The image above is a full
frame of the video from which these clips were cropped. This image shows the blockage
in the bayou that prevented me from moving closer in the kayak. The birds were far behind the trees along the
bayou in the foreground. The black dots show points at which the bird was visible in the video during the swoop.
At 3:18, there were
two successive swoops (movie plays at half speed). The image above is a full frame of the
video from which this clip was cropped. As indicated in the image, an upswoop from the right side of the picture is followed
by a downslope to the left side of the picture. The bird is far in the background and only appears at a few points
along each path,
but it is clear that there are two swooping events.
Between 5:10 and 5:36, events that involved two birds
appeared in the red boxes in the image above. At 5:10, there was a
swooping landing in which the bird ascends nearly vertically. As discussed
here, the body is black (including the belly) and the underside of the right wing is mostly white.
The long vertical ascent is not consistent with any other candidate species.
When the bird flies to the right (movie plays at half speed) at 5:35, it appears to have a
black body and lots of white on the wings.
At 5:36, there was a level takeoff from behind a tree. It is clearly a large bird on the
basis of its size relative to
the substantial, broken-off tree. The deep and rapid flaps are very unusual for a large bird and are not consistent with
any other candidate species, but they
are consistent with historical accounts of takeoffs of the Ivory-billed Woodpecker and with the deep and rapid flaps of
the closely-related Imperial Woodpecker at takeoff.
In this movie (brightness adjusted to make the wings easier to see), the takeoff in the
video is compared with takeoffs of Pileated Woodpeckers and an Imperial Woodpecker (shown here with
permission from the Cornell Laboratory of Ornithology). The deep and rapid flaps of the bird in the video are quite
different from the flaps of the Pileated Woodpeckers, which take off with a much lower flap rate in non-escape flights,
but remarkably similar to the deep and rapid flaps of the Imperial Woodpecker. At 5:44, there was a
vertically ascending landing that could be the bird that took off with deep and rapid flaps.
a bird hopped behind (or into) the tree
where the takeoff occurred 23 seconds later. The way the bird raised its head just before the hop (perhaps to judge distance)
and the hop itself suggest that it may have entered a cavity. In this part of the video,
both birds (movie plays at half speed) appear simultaneously, one in the lower right and the
other in the upper left.
At about 13:00, I got out of the kayak and set the paddle-cam down but kept it aimed in the direction of the birds. The
camera picked up events in the red boxes in the image above.
At 15:21, there was a vertically ascending landing in which
the underwings appear mostly white near the end. As discussed here, the
bird appears to rotate
about 90 degrees about its main axis during the ascent. Starting at 17:37, the camera captured
this footage of
a woodpecker flying across an opening in the vegetation, climbing upward, moving to the right,
moving back to the left, delivering a blow, taking off, and swooping upward. The audio contains a loud knock
that is slightly out of synch with the blow, apparently due to the distance to the bird. During
the flight across the opening, the body appears to be dark black and the dorsal surfaces of the
wings show a lot of white.
The Ivory-billed Woodpecker has a habit of repeatedly rotating its body from side to side as can be
seen in historical footage in this excerpt from
a presentation by John Fitzpatrick (shown here with
permission from the Cornell Laboratory of Ornithology). As discussed here,
the bird in the video makes
similar motions just after moving to the right. Just before delivering the blow,
the bird flails its wings several times (apparently for balance) similarly to how the
Woodpecker flails its wings in the 1956 film. There is a red glow about the head when the bird is
climbing and after it
moves to the right (movies play at half speed). The red is visible in the raw footage, but the
color has been enhanced to make it easier to see.
This feature does not increase the strength of the evidence, but it is interesting that it appears to be a male
Ivory-billed Woodpecker. In this movie, the bird delivers the blow, takes off into an
upward swooping flight (yet another remarkable flight maneuver), and shows lots of white on the dorsal surfaces of the
wings (consistent with Ivory-billed Woodpecker). Based on the delay between when the blow is visible and audible, the
distance to the bird appears to be on the order of 100 meters. The loud knock is easy to hear with good speakers at
high volume in a quiet room, and it was apparently a powerful blow. There appears to be white on the belly when the bird
delivers the blow, but it can be seen that this is light-colored vegetation in the foreground by noting how the dark body
emerges from behind the vegetation when the bird starts moving to the right just after the climb.
At about 20:20, I got back in the kayak. At 24:37 into the video (not counting a brief interval after 24:34, when the
camera was turned off while the sighting was reported by radio), there was a swooping
flight in the red box in the image above. The
takeoff (movie plays at half speed) is similar to the takeoff at 2:02. The bird appears to
change direction just after a noise (something apparently hit the kayak). The flight path extends below the field of view,
but the bird reappears in the lower left of the red box in a vertically ascending landing
that is similar to the landings at 3:18, 5:10, 5:44, and 15:21. As in the landing at 15:21, the bird apparently rotated
about its main axis while ascending. It is difficult to resolve details against the bright background, but there are several
ventral features consistent with Ivory-billed Woodpecker, including the color of the belly
and underwings, the shape of the wings, and the length of the tail. When the bird appears
after the landing (movie plays at quarter speed), there are several flashes of white that are
consistent with the white triangular patch on the
folded wings of an Ivory-billed Woodpecker.