Day-to-day log of the 2008 search season
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10-1-07. I’ll have something new in my bag of tricks when I head south again next week. I’m as excited about
as I was about
paddle-cam last year. My friends at work, Greg and Mike, modified the mount, which is marketed as Bino-Brac by Astronomy-Shoppe, so that the camera sits lower on the binos and is more securely mounted. I will line up the camera so that it sees the same field that is seen through the binos at maximum magnification. It’s a shame that I didn’t come up with this idea a long time ago. When I got the video in the Pearl in February 2006, I kept the camera running in my right hand while trying to spot the bird through the binos using my left hand. I alternated between looking through the camera and the binos. Since the image is very small in the viewfinder, it was impossible to see the bird through the camera. When I was looking through the binos, the bird must have been hiding behind the branch on which it was perched. So I never saw the bird other than detecting motion. By aiming the camera and binos simultaneously with bino-cam, I probably would have gotten an incredible look at a perched ivorybill and much better footage. When I got the video in the Choctawhatchee in January 2007, I set paddle-cam on my lap, aimed it in the direction of the birds, and kept watch with binos. I got a good look at the dorsal side of a right wing when one of the birds flew to a different perch. I would have gotten good footage if I had been using bino-cam. I plan to continue using paddle-cam while in the kayak this search season. The intended application of bino-cam is tree-top observing. I will use the high-def camera with a 2X extender lens and the focus set to infinity. With this set-up, I won’t have to decide between reaching for the binos and reaching for the camera, and I should be able to get good footage out to at least a few hundred meters if the light is good.
10-5-07. My car is having problems, and they have to order one of the parts. So my return to the Pearl will be delayed for a week or so.
10-15-07. The part for the car arrived, but the repair shop botched the job. Before heading south, I’m going to have to get this resolved and then drive the car locally for a few days in order to make sure it’s ready for the trip. I did some additional testing with bino-cam. I put the camera on full zoom in order to check the alignment of the camera with the binoculars. The results were very promising, as illustrated by these images of
perched Mourning Doves
and a flying Blue Jay (the images are slightly blurry since the focus was set at 50 m and the birds were more distant). The images were reduced in size from the original high-def video frames.
10-16-07. The car is finally ready for the road. I’m planning to get underway tomorrow morning.
10-18-07. My car, which one of the visitors to the Pearl aptly named the Ivory-bill Bomb, just died near Mobile, Alabama. I was fortunate to be approaching an exit (it was actually Exit 13) when ominous metallic noises started coming from under the hood. Considering all the long trips that I’ve taken in old cars, it’s amazing that something like this hasn’t happened to me before. The repair shop agrees with my assessment that the engine is blown. In accordance with several of Murphy’s Laws, this had to happen after I waited around to have repairs done, installed new tires, and got nearly a thousand miles into the trip. I’m going to try to get a deal done on a new car in the morning.
10-19-07. I’m at the dealer picking up an
‘08 Honda Civic.
It’s a nice little car, but I hate to let go of my trusty old
10-20-07. I have arrived back at the Pearl. Besides getting settled in, I need to find a roof rack for carrying the kayak on the Honda. The weather is gorgeous, and the birds are very active. The Great Horned Owls, Bubba and Virginia, were calling this morning near the house in Waveland.
10-21-07. I wasn’t able to locate a roof rack this weekend. I’ll check the on-line options on Monday. I don’t want to load the kayak on a brand-new car without a proper roof rack. I’m definitely missing the Ivory-bill Bomb, which would go just about anywhere with a kayak or canoe on the roof.
10-22-07. It’s been raining all day. I have located a roof rack but won’t be able to pick it up until tomorrow.
10-23-07. I have obtained a roof rack, but another obstacle has arisen. I seem to be getting sick and have an appointment with the doctor tomorrow morning. I hate to miss another day, especially since the weather is finally clearing up, but it’s essential to watch your health when doing field work.
10-26-07. I finally made it out in the Pearl today. It was great to be back in the kayak. The weather was very nice, and there was lots of woodpecker activity. I saw an immature Red-headed Woodpecker in the interior of the Pearl. I usually only see this species on the edges of the Pearl and don’t recall any previous sightings in the interior. Since Katrina hit more than two years ago, a huge branch had been hanging precariously from the top of a tree. I always wondered how it stayed up there. I noticed this morning that it finally fell sometime since I was last out there in July.
10-27-07. I decided to stay in today since I still have a sore throat that seems to be similar to the one that put me in the ER in April 2006. While back home in Virginia, I had a lot of catching up to do and little time for exercise. I got out of shape and don’t have much stamina. The thought of paddling for several hours and then climbing a cypress seems very daunting right now. I’m going to have to gradually work myself back into field condition. If I were on a professional ivorybill searching team, I would probably be put on waivers for showing up at camp out of shape.
10-28-07. I visited an area further north in the Pearl. There’s a ridge up there that I was hoping would have trees providing good views out over the swamp. There are some pines on the ridge that look promising. Pines are pitchy and brittle according to the experts, but I might give one of them a try.
10-29-07. After the hike yesterday and the kayak ride on Friday, I feel like I’m starting to get back into shape. The thought of a trek deep into the Pearl seemed intimidating a few days ago, but I should be ready for one this week.
10-30-07. On the way out of Stennis last night, I was sad to see a
Southern Fox Squirrel
dead on the road. It was at the spot where I used to see one several months ago. This specimen was 25 inches from the tip of the nose to the tip of the tail. I spent three hours in the kayak this morning. There was a great deal of woodpecker activity. Familiar landmarks from Katrina are gradually disappearing. An M-shaped branch that appears on the bank in the through-the-gap video has broken off. I found a spruce pine in a good location that has what appear to be strong branches more than 80 feet up. This tree should provide a great view over the 2006 hot zone, but I’ll have to consult with the experts since pines aren’t as safe as cypresses.
11-1-07. I took the climbing gear out to the pines and sized them up (there are actually two of them right next to each other). There are good-sized branches fairly high up, but it’s not clear if they’re high enough to see over the surrounding forest. I took more height data and photos, which I’ll evaluate tomorrow. I’ll also post some photos tomorrow, but I’m too exhausted right now. After checking out the pines, I kayaked up beyond the area where I broke my arm and saw two huge gators. I looked for tall trees hoping that we had overlooked one in June. There’s a cypress that looks promising, but I’ll have to evaluate the data tomorrow.
11-2-07. After checking out
yesterday, I visited a
cypress that we rigged in June.
I’ve never climbed that tree, which is miles to the north of the other trees that we rigged. On the day it was rigged, I didn’t have a clinometer for measuring heights (a laser rangefinder is also required). I measured it yesterday and was surprised to find that it’s rigged at over 80 feet. The view is partially blocked by tall hardwoods in one direction, but it provides a good view in other directions. Since this tree is much easier to reach than the others, I’ll give it a try in the near future. I didn’t climb it yesterday since it was getting late when I arrived.
11-3-07. I stopped to marvel at Comet Holmes on the way out of Stennis late last night. It’s easy to see and quite an unusual comet.
11-4-07. After another long day in the office yesterday, I arrived back in Waveland about midnight and found the door wide open and gang graffiti painted on the front of the house. They smashed the front door window with a brick and rummaged through everything inside.
11-5-07. Order has been restored. I repaired the damage to the house and painted over the graffiti. I also started cutting the weeds back in the yard. The birds like a weedy yard, but it’s not good for an isolated house to appear vacant.
11-6-07. Early this morning, I passed by the tallows and found them loaded with fruit, which probably isn’t ripe yet. I spent the morning in Tree 6. It was my first time in that tree, which is the only one that we have rigged in the hardwood zone. I got up to about 78 feet, but the view isn’t as good as it is in Tree 5 since the trees are taller in the hardwood zone. The view is pretty good in
this direction but not as good
this direction. A Wood Duck came from
this direction and flew by within twenty feet. I could hear the wind whistling through its feathers.
11-7-07. I’ve had pain in the heal/arch area of my right foot for more than a month. It really flared up yesterday, probably as a result of lugging climbing gear. I’m going to let it rest for a day or two and will try to see a doctor to have it checked out.
11-11-07. I took a kayak ride through the area where I recently saw two huge gators. On the way up the channel, I inadvertently paddled right over one of them, which thrashed violently and gave the kayak a hard blow with its tail. The loud sound of the impact gave me the impression that gators must be very bony just beneath the hide. At about the same spot on the way back, a gator thrashed a few feet away and gave me a good splash. Those encounters really got the adrenalin flowing.
11-12-07. Yesterday I noticed that someone cut two fallen trees that were blocking the waterway that goes to Tree 6. This will make it easier to get there by kayak. I have ordered a
gear sled that will make it easier to get to Tree 5. The shortest route to that tree involves an hour walk through the swamp. When carrying the climbing gear, the extra weight causes my feet to sink much deeper into the mud, which turns the walk into a death march. I plan to spend more time in the tall trees now that it will be easier to get to them.
11-13-07. I received the gear sled and am very excited about it. It’s lightweight, durable, and just the right size for a loaded backpack and climbing gear. The low-profile design should make it stable when going over rough terrain.
11-15-07. Yesterday afternoon I visited the doctor, who diagnosed the pain in my foot as plantar fasciitis.
11-16-07. Gretchen and I spent some time in Tree 4. It was my first time up that tree, which provides excellent views.
The view from above the trees is very different now that most of the tupelo leaves have fallen.
This is what it looked like from Tree 2 back in July. A pileated flew by just as I was entering the crown.
A Great Blue Heron was perched in a cypress about 300 meters away.
A Great Egret was looking for something to eat down below. I tried out the gear sled and swamp boots, which both worked great. It sure helps to have proper gear. My right foot was feeling fine this morning, but now it’s throbbing. I might have to take a few days off to let it recover, and that would probably be a good idea independent of my foot with the deer season opening. After finishing the climb, we found that the water had gone down and the boat was partially grounded, but we managed to get it out. On the way back, we checked out some tall trees that have come into view now that the leaves are down. One of them is near where we had sightings last fall and has a huge cavity.
11-17-07. It was great to get back up in one of the tall trees yesterday. On the way up, it’s always exciting to see trees in the distance gradually coming into view. When you finally get above the surrounding canopy, it’s like popping up over the clouds and into the blue sky while flying. One of the highlights of the climb was seeing Tree 5 towering over the canopy a little over 400 meters away. It was my closest view of that spectacular tree from another tree.
11-29-07. I went for a kayak ride with a friend who is visiting from Washington and showed him the 2006 hot zone. I used the old kayak, which is still useful despite being a bit leaky.
12-2-07. I had a possible sighting in Mississippi this morning. The bird flew into an open area and then rapidly dove down and turned back into the woods. There was white in the right places on long and thin wings. This was near the edge of the Stennis buffer zone in an area with a mixture of pines, hardwoods, and cypresses.
12-6-07. I have recently been exploring this
secluded waterway, which reminds me a lot of the 2006 hot zone. Since it’s just a short flight from that area, it seems likely that the ivorybills have visited it over the years.
12-7-07. I visited the tallow trees yesterday and found them loaded with fruit, but there still aren’t any birds feeding on them. Last year, many woodpeckers and other species were seen feeding in the tallows in late December and early January, and an ivorybill was seen in the area on December 20.
12-8-07. There’s something that I love about a
foggy morning in the swamp. I was eager to get an early start this morning after looking out and seeing the fog. It was interesting to watch a pileated foraging near the top of a sweetgum.
12-9-07. I visited the 2006 hot zone with a birder from Illinois. We noticed that someone has been making trails using a chainsaw. It’s unfortunate to see such illegal activities in an area with a critically endangered species. It’s interesting how many of the trees that came down during Katrina and landed in the water look like
this one. Notice that long branches go deep into the water and prop the tree up above the water while most of the branches on the other side of the tree are small. This may be entirely due to the fact that branches tend to be longer on the open side of a tree that faces the water, but another possible factor is that a tree might tend to rotate while falling so that the side with the largest branches leads the way.
12-10-07. I decided to stay in today and let the visitors from Illinois be my eyes and ears in the field. They visited the area that I recently started watching closely, saw lots of woodpeckers, and agreed with my assessment that the habitat looks promising. A visitor from Georgia reminded me that he heard high-pitched calls in the Pearl earlier this year. You have to be careful about these calls since the Blue Jay bell call is similar, but he caught a glimpse of a large bird just before the calls started. If you hear something that sounds like bell calls and there’s no sign of a Blue Jay, I would recommend firing up the video camera and switching over to full-alert status.
12-11-07. I’m going to be tied up in the office for the next day or two. I asked the birder who heard the high-pitched calls for more details. The date was January 31, 2007. The location was a short distance from the 2006 hot zone but on a different waterway. After hearing the calls for several minutes, a large bird that appeared to be a woodpecker flew from the direction of the calls and disappeared behind trees. There were no more calls after that, and the bird was not seen again. Another birder was visiting from Idaho during that period, and he heard kents on February 5, 2007, near the area where I had my first sighting on February 2, 2006. That location, the 2006 hot zone, and the location where the birder from Georgia heard the high-pitched calls form a nearly equilateral triangle with sides a little less than a kilometer. Not far from there is an area that I have dubbed the Bermuda Triangle, where I broke my arm, capsized the kayak, had a close encounter with a gator, and nearly stepped on a water moccasin.
12-15-07. Gretchen and I rigged Tree 7, which is in the area that I recently started monitoring. After noticing several wasps, we decided to stop climbing a little lower than planned.
The view is marginal from that height, but it should be pretty good at the top. It was very windy up there, and the tree was swaying despite being a very sturdy cypress.
12-16-07. After slogging through the swamp yesterday, my foot is now throbbing again. It looks like I’m going to be restricted to the kayak for a while. I’ll have to let my foot recover for a few days before getting back out there.
12-17-07. One of my friends has a poster-sized copy of a high-quality photo of the Pearl. There’s no legend on the photo, but it’s clearly not the visible spectrum. Different tree species show up in different colors, and cypresses really stand out from other species. Individual trees are resolved, and several of the cypresses that we have climbed show up in the photo. The mother of all cypress groves is lined up in a row that runs for a few miles through the most remote part of the Wildlife Management Area. I’ve seen part of this grove from Tree 5, but I hadn’t realized the extent of it. It seems to be an ideal location for a roost, and Tree 5 provides an excellent lookout point for monitoring birds flying between that grove and the hardwoods.
12-19-07. A local birder reported seeing a female ivorybill in the pines a little over a mile to the north of where I had a possible sighting a few weeks ago. There are many stands of dead pines in that area. The sighting was in late June, which is consistent with Stoddard’s observations of ivorybills in pine forests during the summer and fall.
12-20-07. I visited the area of the June sighting. The habitat is poor in that area, but the bird was flying from a direction where there are lots of dead trees. One of these days, I need to take a flight over the pines in and around Stennis and look for large stands of dead trees. Searching in the pines doesn’t seem promising, but a look from the air might provide some ideas. I got the idea for climbing cypresses while crossing the I-10 bridge at the Louisiana-Mississippi border. At first, I wished that I could stop on the bridge and watch from there, but then I saw several cypresses towering over the surrounding trees.
12-22-07. I visited the tallow trees this afternoon. They’re loaded with food, but I still haven’t seen any birds in them. They must be late this year.
12-24-07. I visited the pine forest near the northeast corner of Stennis. People rarely visit that area, which often has lots of birds. There were lots of sparrows and robins, but the only woodpecker was a pileated. I went for a walk on even terrain, and my foot held up fairly well.
12-26-07. I took a long kayak ride this morning and visited the 2006 hot zone and the Bermuda Triangle (the area where I’ve had several mishaps). I heard loud pounding noises in the woods, but it seemed to be someone using a hammer. Right after that, I heard something with loud wingbeats fly across behind me. I have obtained a precision compass that will allow me to pin down the locations of tall trees and also to measure distances in situations when there is no line of sight (e.g., the distance between where the ivorybill flushed and the fork deep in the woods where it appears in the video).
12-29-07. I visited the 2006 hot zone to take some measurements. I love the new Suunto KB-14 compass. It gives precise readings, which I double checked for consistency. I used the compass and the laser rangefinder to determine that the distance between the snag from which the bird flushed and the fork in which it appeared near the end of the video is 218 m. I also determined that the fork is about 77 m deep in the woods and that the bird initially flew about 60 m to the position where it appeared through a gap in the vegetation. The distance between the position where I obtained the video and the fork is 128 m. I previously estimated some of these distances by GPS, which didn’t provide the accuracy that I expected (perhaps due to tree cover).
12-31-07. I visited the pines south of Stennis this morning. There wasn’t the slightest ripple on
this pond, which is near the spot where a biologist saw an ivorybill in 2002. The photo may seem confusing unless studied carefully.
1-1-08. I visited the tallows. A few passerines were feeding in them, but there are still no woodpeckers.
1-2-08. I visited the tallows twice today, but there still wasn’t any activity.
1-3-08. I did some exploring in pine forest at Stennis that borders on the swamp near one of the trees that we have rigged. That area seems promising since it’s closed to the public, isolated from human activities, and not too far from the 2006 hot zone.
1-4-08. I visited the Honey Island Swamp to check out an area where a local birder heard something similar to the sequence of taps in the Singer Tract recording. What made this report really intriguing is that a pileated flew in during the tapping and gave territorial calls. Pileateds here in the Pearl are a lot smarter than many humans in that they know that ivorybills exist, and they can get feisty when ivorybills encroach on their territories. On February 16, 2006, I heard three kents that were immediately followed by stern territorial calls from a pileated. I saw a Red-headed Woodpecker, which is rarely seen in the interior of the Pearl. The weather is finally warming up after the bitter cold spell.
1-5-08. I spent the morning in the kayak. It was warm enough to go without a jacket. I thought about going up one of the trees, but it was too windy.
1-6-08. I did some exploring near the Mississippi coast this morning and noticed birds (including woodpeckers) feeding on the tallows there.
1-7-08. I only had time for a short visit to the area south of Stennis today. I took a photo that explains the photo that I posted on December 31. The explanation is posted
1-9-8. I took a nice kayak ride into the 2006 hot zone this morning. There was lots of bird activity, including an unusual number of swallows.
1-11-08. This afternoon, I visited the tallows near where there was a sighting a little over a year ago, but there’s still no feeding activity in those trees. Later on, I found a pileated feasting in a tallow at Stennis.
1-12-08. Gretchen and Tasha joined me for a
gorgeous morning in the swamp. We climbed Tree 2, which is back in
this bayou. Lots of birds flew by this morning, including vultures, a kestrel, a flock of blackbirds, a heron, and cormorants. We heard lots of woodpeckers and a Barred Owl from the top of the tree. An Osprey can be seen in the foreground of
this photo of Tree 5. I used the precision compass from up in a tree for the first time and got the bearings of several trees and landmarks. We discovered a convenient practical use for the compass; after I determined the bearing of Tree 5, it was easy for Gretchen and Tasha to use the compass to make sure they were looking at the right tree. Now that the leaves have fallen from trees in the foreground, many trees in the large grove of cypresses can be seen from Tree 2, and some of them appear to be over 90 feet tall. The compass was useful for pinning down some tall pines near the 2006 hot zone. During previous climbs, I thought I had the right trees. Now I know for sure. I got the bearing of what I thought might be Tree 3, and it checks out.
This panorama shows part of the big grove several hundred meters in the distance. Some of the trees appear to be much taller than the 73 foot vantage point in Tree 2 where the photo was taken.
1-14-08. I spent the afternoon out in the kayak and got back just as it was getting dark. It was nice to experience dusk out in the swamp for a change. I heard a loud single rap near the 2006 hot zone just after sunset. The Barred Owls have become very vocal and were calling throughout the afternoon.
1-15-08. I spent another afternoon out in the kayak. The past few days have been absolutely bayoutiful. A Bald Eagle was soaring high over the Pearl. It was entertaining to watch several waves of Black Vultures returning to their roost.
1-17-08. I took a long kayak ride this morning and went all the way past the Bermuda Triangle (there were no unfortunate incidents in that area this time). I found some fresh foraging sign that looks very interesting. There was quite a bit of it, and it looks like it was done all at once. This isn’t far from where a birder recently heard double knocks.
1-18-08. Going over the I-10 bridge as a passenger, I used the precision compass to get the bearings of one of the largest trees and a thick clump of trees in the big grove of cypresses. I went by the tallows again, but there was still no feeding activity. I also spent some time in the Honey Island Swamp.
1-20-08. I visited the 2006 hot zone and was planning to also visit the Bermuda Triangle, but the water was a bit low. It was a nice day despite being a bit cold and windy.
1-22-08. Since the water was high, I paddled out to the Bermuda Triangle this morning. I’m planning to drive to the Choctawhatchee this evening and might not be able to post updates for a day or two.
1-23-08. I spent the morning paddling to the site where I obtained video clips a little over a year ago in the Choctawhatchee. I wanted to inspect the tree from which the bird flew in the video, take measurements, and get photos. I tried to do this in April, but the tree was hidden by leaves. Although high water prevented me from getting the job done on the second attempt, I heard a nice double knock on the way out there. I took along two photos and the coordinates of the site, but it turned out that this information wasn’t sufficient. The water was so high that the entire forest was flooded. It was tricky getting back there with the current flowing through the forest as shown in
this paddle-cam image. I used the GPS to navigate to the site, but the key landmarks in the photo were submerged. Having studied the video extensively, I recognized a few landmarks higher in the scene, but they weren’t sufficient to find the tree (which I fear may have fallen by now). I tried moving around in the kayak and looking to the east in hopes of spotting the tree, but this was difficult in the strong current. On the way back, I was surprised to cross paths with Brian Rolek way out there. He said the water was as high as he’s ever seen it. Shortly after talking to Brian, I came face to face with a Water Moccasin that was coiled around a tree branch (very much like the medical symbol). Back at the landing, I had a nice chat with Rob Tymstra and two other ibwologists. I would advise any birders venturing into the Choctawhatchee to be very careful during high water. This river is always dangerous due to the strong currents. When the water is this high, it’s easy to get lost out there. Despite having spent some time in the area, I was anxious about finding my way back. I’ll give it another try when the water goes back down. This was my first time on the highway with the kayak on the Honda, which has two convenient places to hook lines under the front bumper. It rode very nicely up there.
1-24-08. Water, water, water. Yesterday, it was flooded in the Choctawhatchee. Today, there’s a steady rain in the Pearl. It was disappointing to fail to get the job done yesterday, but the tree that I wanted to find appeared to be more than 100 meters from the observation position, and it was only visible from a certain position between the trees in the foreground (the tree only shows up at certain times in the video as the kayak drifts around). Making sure you have the right tree is like peeking through a keyhole. Everything needs to be lined up just right. When I tried in April, the leaves were in the way. With the water flowing rapidly and key landmarks submerged during the latest attempt, I wasn’t able to maneuver the kayak into the position of the keyhole. I’ll give it another try soon. It’s always interesting to visit the Choctawhatchee, and it’s only about 250 miles from the Pearl. There’s a huge cypress right next to the observation position. Since the sighting was shortly after dawn, that tree is a good candidate for a roost site. According to a
NOAA web site
that posts water levels for the Choctawhatchee, the water was right about at the level corresponding to “extensive lowland flooding” during my visit.
1-25-08. The air was a bit icy today, and I began to feel it after sitting at a stakeout near the Bermuda Triangle and getting caught in a light rain.
1-27-08. This morning, I made the rounds at Stennis, which I hadn’t done for a while, and discovered an overgrown trail that leads to the vicinity of Tree 7. I visited the overgrown canal where I heard kents eight years ago at about this time of year. My first thoughts of climbing something to get a view out over the Pearl involved
this tower. The walkway is 137 feet above the ground. While visiting the tower, I took a GPS reading that is consistent with a bearing measurement that I took from 5.3 km away in Tree 2.
1-30-08. Two other searchers joined me in a visit to the big cypress grove. Video footage of some of the habitat that we waded through is available
here. We found several trees that are comparable to Tree 5 as well as several large cavities, including a fresh one. I computed the heights of several of the cypresses. Seven of them are taller than Tree 5, and one of them exceeds 100 feet. All of them have “bomber” branches near the top that would make them excellent for climbing. There are even taller trees that can be seen from the I-10 bridge, but we didn’t find them this time. I had a bad fall and caught myself with the arm that I broke last year. It was a severe jolt to the arm, but it held up. I dropped my watch in ankle-deep water, but we weren’t able to find it in the mud. I can barely walk on my bad foot, which was throbbing toward the end of the hike. I’ll be restricted to kayak duty for a while.
1-31-08. I have prepared vertical panoramas of trees that are
96 feet tall. These trees appear to be very healthy, and they’re mixed in with other tall trees.
This cavity is approximately four inches in diameter (the diameters of the red circles are four and five inches). The vertical diameter appears to be less than four inches in part due to the viewing angle. It’s interesting how
this branch fell on a fallen tree and broke in half.
2-1-08. A violent storm last night was followed by a gorgeous day in the Pearl. Some of the resident birds have started singing. I visited the 2006 hot zone and saw lots of woodpeckers, including
2-2-08. I produced
this clip of a pileated from footage that I obtained in the Pearl last year.
2-3-08. I visited the 2006 hot zone and discovered who’s been using a chainsaw up there. A hog hunter has opened up a long stretch of a waterway that used to be isolated from boat traffic by fallen trees. The motive for this senseless (and illegal) act was to get to an area that can easily be reached on foot from the other direction. This isn’t the only threat to the Pearl ivorybills. A few days ago, I heard machine gun fire coming from the live-fire range for the first time. When I photographed a nice looking cavity a few days ago, I measured the distance with the laser rangefinder (as usual) but also measured the inclination angle (since we were interested in the height). From my vantage point, the cavity was 34.5 degrees above the horizontal, which reduces its apparent vertical size by about 18 percent. Using the range information to scale the image and using the angle information to stretch it in the vertical direction, I obtained
this comparison, in which the red circles are four and five inches in diameter. This is the most impressive cavity I have seen. It looks like it was recently made with woodworking tools in a live cypress that isn’t hollow.
2-5-08. Since the water was high, I decided to take a kayak ride out to the Bermuda Triangle. Strong gusts of wind started up just after I arrived in that area, and I turned back in order to beat the storms that are predicted for this afternoon. There was a good deal of pileated activity this morning. I saw or heard eight of them on the way out. I sat near the bank and listened for a while shortly before turning back, and a Barred Owl flushed from nearby. It moved a short distance away and didn’t seem to mind my presence. I kept hearing a high-pitched call that resembled the alarm call of a chipmunk. I don’t know what was making it, but it might have been reacting to the owl.
2-6-08. It was a spring-like day. Leaves and flowers are already starting to come out, and the birdsong has really picked up. I visited the 2006 hot zone and had a nice drift back with the current.
2-7-08. This afternoon, I finished preparing a talk that I’ll be giving in Sarasota at the end of the month. For the talk, I took photos of some of the
gear that I’ve been using in the Pearl. The gadgets include the GPS, laser rangefinder, clinometer, and precision compass. A GPS is essential for marking locations, navigating to specific points, and avoiding getting lost. The rangefinder has many uses, including measuring the heights of trees and distances to objects. The clinometer (which was donated by the finder of the world’s tallest tree) is used to measure the elevation angle of an object above the horizon. This device is essential for measuring tree heights. The precision compass makes it possible to measure the bearing of an object to a fraction of a degree. This device is useful for estimating the coordinates of objects (such as trees) and can also be used along with the rangefinder for measuring distances by trigonometry when there isn’t an unobstructed line of sight between two objects. The climbing gear (which was donated by an anonymous biologist) includes a harness that is worn around the waist, ascenders that only slide in one direction along the climbing rope, leg straps attached to one of the ascenders (the legs do most of the work when climbing), a grillon (the long red line) for safely tying yourself in at the top of the climb, a gri-gri (the small device in the lower right) for safely descending, climbing rope and rope bag, and a foldable cube that is very useful when reeling in or out lines and ropes.
2-8-08. It was another bayoutiful morning in the Pearl. I saw my first otter of the season. The water levels and currents are both decreasing. If the same is happening in the Choctawhatchee, I will soon be going over there for another visit.
2-9-08. I paddled out to the 2006 hot zone and spent a few hours hanging out and enjoying a gorgeous day. It was interesting to watch a pair of Red-bellied Woodpeckers make repeated trips to an American Holly tree for berries. The Barred Owls have been very active lately. This morning, I noticed that activity has suddenly picked up in the Yaupon Holly trees.
2-10-08. One of the visitors went out with me to climb two cypresses in the big grove. After getting about 60 feet up the first tree, I noticed a spectacular tree a few hundred meters to the west. That tree is about 110 feet, and I climbed up to 94 feet. It was my highest climb by far and the tallest cypress that I have found in the Pearl. It might end up being my last climb. The device that I use for descending is called a gri-gri. It securely attaches you to the rope, and there’s a lever to pull to gradually (supposedly) belay yourself down. When I first started climbing, the gri-gri seemed to work very smoothly, but then it started having problems with the rope getting jammed. I ordered a new gri-gri and tried it out today, but it was even worse. The rope got jammed when I was still way up there. Then it suddenly gave way, and I went into an alarming free fall for about three feet. When this happened, I instinctively grabbed the rope with my right hand and suffered nasty rope burns. I had several of these hair-raising events on the way down. I’ll try to figure out what’s causing this problem, but I’m not sure about doing any more serious climbing after this experience. While up in the tree, I took
this photo looking down,
this photo of some of the big trees nearby, and
this photo that shows many of the cypresses in the big grove as well as the rocket towers about six miles in the distance at Stennis.
2-11-08. Having too many aches and pains to go out today, I limited myself to putting together panoramas from Tree 0 (the 110 foot cypress)
looking toward Stennis and
in the opposite direction. Since the camera was held at 94 feet, the trees that break the plane of the horizon are over 90 feet. Some of the trees nearby are over 100 feet.
This photo shows the view looking straight down from 94 feet.
2-14-08. I went for a nice kayak ride this morning, but my right arm was snapping and popping while paddling (similar to when scar tissue was breaking away in my left arm last year). This might have something to do with grabbing the rope during the free fall the other day. I saw a kestrel and a creeper, which I don’t see very often in the Pearl.
2-15-08. It was nice to spend two days in the field with the university searchers, who have completed their work in the Pearl. Both days were very productive, and they were my first explorations in the big grove of cypresses. We found some very interesting cavities, a surprising number of cypresses over 90 feet, and one incredible cypress that is about 110 feet. One of the searchers saw a White-tailed Kite a little to the north of where I saw one last year on January 6. I’m not aware of any other sightings of that species in the Pearl during the past few years. Although there’s no way of knowing the number of days that species has been present during the past two years, this is a good example of how a rare species can go undetected for long periods in a large river basin. One group of visitors has departed, but another group has arrived, and we have lots of plans for the next several days.
2-16-08. There were five of us in the field today. Late in the afternoon, three of us had an interesting sighting near a large cavity that I found in a sweetgum last year. I picked up the bird first and got my binoculars on it. It was black with lots of white on the wings. I noticed a large white patch on the trailing edge of the dorsal surface of the right wing. The other observers didn’t see field marks, but we all noticed a rapid gliding flight. I noticed the bird rock from side to side as it maneuvered to land. One of the observers fired off a high-resolution photo but missed the bird. I regard this as a definite sighting on the basis of the large size, markings that were observed on the right wing, the way it was gliding, the way it rapidly disappeared in cover, and a subsequent
definite sighting a short distance to the south.
2-17-08. We returned to the area of the sighting and got caught in a severe thunderstorm. After dodging lightning bolts and hail stones on the way back, we reached the shelter of the cars just as it stopped.
2-18-08. Four of us split up into two teams and covered about 25 miles today by water and foot. We’re tired and going to head to Waveland for BBQ.
2-19-08. In the same general area as the possible sighting, we heard a series of kent-like calls, and Richard Martin recorded some of them (my camera was inoperable due to moisture condensation at the time). The calls don’t have a strong metallic quality, but the source was far enough away (perhaps a few hundred feet) for the higher frequencies to be attenuated by vegetation. The sonograms of these calls have similarities to the sonograms of known and putative kents. We returned to the “warm zone” this afternoon, and I heard two distant kent-like calls.
2-20-08. I returned to the warm zone and heard three more calls from the same area. I didn’t stay long because I’ve gotten sick and was making too much noise by coughing. This has been such a busy week that I hadn’t gotten around to taking GPS readings until this morning. It was interesting to find that the locations of the sighting and the calls are only 240 meters apart, and they’re along the same waterway. This wasn’t obvious before consulting the map because we approached these areas from different directions. It’s difficult getting around out there because of
blackberry patches that are thick enough to secure the perimeter of a P.O.W. camp.
2-21-08. I’ve got a cold and it’s a rainy day. I’ll stake out the warm zone later if there’s a break in the weather. I was going through some high-definition video that I took while driving over the I-10 bridge last year and noticed
this image that shows a cypress (on the horizon and about three quarters of the way across the image) that appears to be about 120 feet tall. I’ve made two trips out to that area but have not yet managed to find that tree. The rain let up late in the afternoon, and I visited the area of the recent sighting. I stayed until dusk and noticed bats for the first time this season.
2-22-08. I visited the site where the calls were recorded but didn’t have any luck. It was muggy and the skeeters were out in force. When we heard the calls the other day, my camera wasn’t functioning due to moisture condensation.
2-23-08. The visitors kept me on the go this week, and I got sick after getting caught in a downpour. With a long drive to Sarasota coming up next week, I decided to take it easy today. Although the two calls that I heard late on February 19 were weak, one of them shows up fairly well in a sonogram and has a similar signature to the calls that were recorded that morning. I heard three similar calls in the same area the next morning, but there hasn’t been anything since then. I wanted to clarify some details of the sighting on February 16. The bird glided in at high speed on fixed wings. I got binoculars on it and noticed that it tilted from side to side as if adjusting for a landing. I noticed a large white patch on the trailing edge of the top of the wing just before losing it in the trees. The bird came in from an angle such that it probably didn’t see us at first, and the lighting was excellent. It might have been a spectacular sighting if I had been a little faster with the binoculars. I’m encouraged by the locations of the sighting and the calls relative to each other and to the 2006 hot zone. We have a tree rigged not too far from this area.
2-24-08. This morning, I recorded the two calls in the top sonogram in
this image. It was clear that these were Blue Jay calls, and in fact I saw the bird that was making them. The lower sonogram corresponds to the calls that Richard Martin recorded on February 19, which have a Blue Jay quality as well as kent-like characteristics. The calls that were recorded today lack variations in pitch (like kents), but the frequencies turn on and off at different times (unlike kents and the kent-like calls that were recorded on February 19). Since the frequencies match in the two sonograms, it’s now clear that the February 19 calls must have been made by a Blue Jay.
2-25-08. I’m making final preparations for the trip to Florida this morning but hope to make it out this afternoon. During a recent visit, Richard Martin obtained
this photo of a pileated flying near the forked tree in the Pearl video (Richard believes the pileated was just on this side of the tree). It would be very interesting to get a photo of a pileated perched in that tree. I went for a walk in the Pearl this afternoon and came upon a cottonmouth on the trail. I’m leaving for Florida tomorrow and should be back to the Pearl in less than a week.
2-26-08. I spent the day driving to Tampa. It’s always interesting to cross the Choctawhatchee, Chipola, Apalachicola, and Suwanee. It’s depressing to see all the development that has occurred in Florida since I moved here in 1965. A friend is going to take me in his boat to an area where his father saw an ivorybill in the 1950s. I’m also planning to visit the Hillsborough River, where we always went to escape the heat of summer many years ago. I’m eager to see “The High Cypress,” which had a nice fork 50 feet up for jumping into the river. I sure hope it’s still standing.
2-27-08. I went to check on
“The High Cypress,”
which we used to jump out of many years ago. The water is higher and the scene has changed, but I’m pretty sure that I found the right tree. Part of the top has broken off, but I recognize the curvature, the stub of a broken branch, and the large fork, which was 48 feet above the water when I measured it in 1974. We would also jump from a branch to the right that was 52 feet up but is now gone. It was a thrill to hear the air rushing by when jumping from that height. I waded through
this swamp to get to the edge of
the Hillsborough River near our old house.
2-28-08. I had a wonderful visit at the
in Sarasota, where I met
Margaret “Canopy Meg” Lowman
and her students and gave a talk on my work in the Pearl to an enthusiastic audience. Meg has done pioneering research in tree canopies around the world and has really been an inspiration for my work in the Pearl. When my little ventures into the swamp start feeling arduous and dangerous, all I have to do is think about some of the things that Meg has done, and that puts things in perspective. I would highly recommend her books,
“Life in the Treetops” and
“It’s a Jungle Up There.”
2-29-08. Before the talk last night, Meg’s students gave a tree climbing demonstration in a spectacular kapok tree, and Bryson Voirin
explained why I’ve been having problems when descending using a
It turns out that this device sometimes has problems for users over 180 pounds, and I’m about 225 pounds. One solution is to switch to a
Stop Descender. Meg and her students are interested in visiting the Pearl and spending some time in the trees watching for ivorybills flying over the canopy. Having such a sighting is by far my most important remaining goal.
3-1-08. Mark Cowart took me for a ride up the Hillsborough River in his motorboat. We were planning to go up to a relatively remote area to search for good habitat. Since the boat seemed to be having a fuel problem, we only made it up to the vicinity of “The High Cypress,” but it was nice to go right over to that beloved tree and actually touch it. I took
this photo from just beneath,
this photo that shows the bend out over the water that made it a great diving platform, and the series of photos in
this composite. In 1974, Mark and I free climbed this tree before installing steps. I was pleased to see that the steps have long since rotted away and didn’t seem to do any permanent damage to the tree. We also used to jump from
this cypress, which had a large branch about halfway up that stuck out over the water. I didn’t hear any parulas during my visit to the river a few days ago, but they have now arrived, and the timing is the same as it has been in the Pearl the past two years. The Hillsborough has more of a tropical flavor than the Pearl, but the area that we visited today is surrounded by development. In small patches of good habitat, we saw this
Limpkin, a good-sized
gator, and many
Osprey. During the summer, we usually went swimming in
this area, where we would jump out of two towering oaks that fell into the river years ago.
3-2-08. I drove back to the Pearl today. I saw a Swallow-tailed Kite soaring above I-75 in Florida, and they should be arriving in the Pearl soon if they’re not here already.
3-3-08. I was worn out after the trip to Florida and didn’t make it out in the Pearl, but a visitor (who also spent some time here last year) was my eyes and ears in the field today. He reports unusually high water levels and the arrival of yellow-throated and parula warblers right on time with the past two years.
3-5-08. I received a
Petzl STOP and found that it lets the rope out very smoothly during descents. Since the rope burns are nearly healed, I’m now ready to get back up in the tall cypresses. But first I’m going to make another attempt to take some measurements in the Choctawhatchee where I obtained the video last year. I’ll be driving there today and should be back to the Pearl late tomorrow.
3-6-08. I heard a nice double rap early this morning in the Choctawhatchee. I stopped to keep watch for ten minutes, and there was no sign of anyone else in the area. I had the paddle-cam running, but the double rap was lost in the noise of paddling, which radiates along the paddles directly to the camera. I returned to the location where I saw two ivorybills and obtained video on January 19, 2007.
In part of the video, one of the birds flew from behind a broken-off tree far in the distance. During two previous return visits, foliage and high water prevented me from getting the same view and identifying this tree. This morning, I found a tree that appears to be in the right direction and about 120 meters from where the video was obtained. A little over 20 seconds before the bird flew, it dived behind the tree in a way that was suggestive of a squirrel. Besides the fact that a squirrel and a large bird wouldn’t coexist in the same spot behind that tree for more than 20 seconds, the top of a barren tree in a flooded forest is no place for a squirrel. It was a beautiful morning, with
early signs of spring. When I got back to the boat ramp, a noticeable amount of new leaves seemed to have popped open during the five hours that I spent in the kayak. I noticed a few cypresses that appear to be favorable observation platforms, but I probably won’t have time to return to the Choctawhatchee and give them a try.
3-7-08. I turned 50 today. It was a nice change from last year, when I woke up in the hospital on my birthday.
3-8-08. I gave the new descent device a full test this afternoon. It lets the line out very smoothly.
3-10-08. I just learned that someone was doing double rap simulations near where I heard one during a visit to the Choctawhatchee last week. Both the time and the location are consistent with my observation (although the location is a bit further than I would expect a double rap to carry). It certainly was a good simulation.
3-12-08. I visited the 2006 hot zone this morning. It had been a while since my last trip up there. It was nice to see that Swallow-tailed Kites and other migrants have returned. The water is still high and the currents are still strong. Paddling downstream through fallen trees is really treacherous under these conditions. Although I’ve been through that area many times, it’s hard to know where debris lurks just beneath the surface when the water level changes. Richard Martin sent me another photo of a pileated flying near the fork tree in the Pearl video. Since he was sitting in the spot where I obtained the video, I was able to scale the images and obtain
these comparisons. Although the ivorybill (20 inches) isn’t that much longer than the pileated (17 inches), the ivorybill is a much more massive bird, and the pileated looks puny by comparison in these images.
3-14-08. I made the rounds on the Mississippi side this morning. The most interesting sighting was a pair of pileateds that appeared to be in the type of long distance flight that would be expected of ivorybills. I saw them coming from far off to the right and tracked them until they nearly vanished to the left, but they eventually veered around back toward their starting point. It wasn’t the first time that I’ve seen such a flight by a pileated in pine forest, where it is conceivable that they would need relatively large territories.
3-16-08. Since I have to return to our Washington office in a few weeks, I’m spending this weekend catching up on things that need to be completed before leaving our Stennis office. I heard a nice double rap in the Choctawhatchee on March 6 and reported it to Geoff Hill. In the same area in January, Geoff heard two double raps and two birders had a sighting. Although Geoff didn’t think anyone would have been simulating double raps in that area, Brian Rolek later informed me that his assistant had been simulating double raps at the top of each hour that morning (he thought the location of the simulations might have been within earshot of my position, but he would have to check on it). I didn’t see anyone else in the area, but the time of the double rap was nearly on the hour at 7:01 a.m. After checking the records, Brian has determined that I was more than a mile from the simulations. Since the double rap seemed to come from a nearby source, the timing was apparently just a coincidence. Hopefully, the birds are still spending time in that area and the Auburn folks will soon get a photo.
3-18-08. It was a gorgeous morning in the Honey Island Swamp. Prothonotary Warblers and Yellow-throated Vireos have arrived since my last trip over there. The leaves are really starting to come out, and we’re getting into the time of year that I suspect is the most favorable for watching for ivorybills flying over the canopy. I have plans to do some treetop observing this weekend.
3-22-08. I’m not going to do any searching this weekend, but I have some tree climbing plans for the coming week. I’m planning to start back to Virginia on March 29. I need to return early this year due to a new project that is starting up.
3-24-08. I made up for the inactivity over the weekend with one of my most grueling days in the field. Gretchen gave me a one-way boat ride to
Tree 5, and I made it to the top right at
sunrise. It was my first serious climb since the incident on February 10. It’s hard to get back on the horse after being thrown, and I had to do it in less than ideal conditions. Tree 5 is about 90 feet tall, the climb is about 80 feet, it’s way out in the middle of the swamp, there are lots of ominous looking dead branches near the top, there were high winds, and I had to do the climb alone. It was an exhilarating climb despite the wind and cold. As
this photo and
this video footage
show, the swamp is beautiful at this early stage of spring, when only about half the leaves are out. Most of the biggest cypresses (including Trees 3 and 5) still don’t have their leaves out. The highlight of the climb was a pair of Yellow-throated Warblers that appear to have a nest near the top of Tree 5. These birds showed absolutely no fear of me and approached
very closely. After what happened on the last climb, I was most nervous about the descent, but the new Petzl STOP worked smoothly on the way down. The climb and the trip back were like a triathlon. After the climb, I had to transport all the gear (including the kayak) several hundred meters through the
semi-flooded forest. This was the most exhausting part of the triathlon, but the kayak ride back was the marathon, taking about three hours due to the strong winds (which always seemed to be in my face).
3-25-08. In some ways, I’m starting to feel my 50 years. Dragging a loaded kayak through a flooded forest nearly kills me. If it’s flooded the whole way, you can just get in the kayak and paddle, but this doesn’t work when there are areas that are dry or shallow or obstructed by fallen vegetation. The factor that makes it so hard to transport a heavy weight through such habitat is that your feet sink in the mud with every step. Just before the end of the drag, I nearly fell in a deep hole and came within inches of getting my waders full of water. I saved myself by grabbing the kayak. One of the things that worries me out in the swamp is getting pulled under by flooded waders. After the drag, I had a long kayak ride back and paddled like a well-oiled machine for three hours, but then the wind started blowing hard in my face. I got to the boat ramp just south of Stennis and was spent. My friends at Stennis, Bob Brown and Steve Stanic, came to the rescue and picked me up. I was staggering out of the kayak with severe cramps in my right thigh as they pulled up.
Here is another frame from the video of the Yellow-throated Warbler that shows its feathers being ruffled by the wind. I’ve always wanted to get a photo
like this of a flicker, which shows the brilliant yellow feathers underneath in ideal light, but the quality is poor since I was panning the video camera.
3-26-08. I had a possible sighting this morning not far from the probable sighting last month.
I noticed the bird as it flew through the far side of
this flooded area. It was a large dark bird with lots of white on the wings, including what appeared at that distance to be a completely white underwing. I spoke to a biologist who has been doing research in the Pearl for several years and who confirmed reports that I had been hearing about logging further north in the Pearl. They have not only logged the area but have made a mess of it with logging roads. It’s a disgrace that such things are happening in a river basin that contains a critically endangered species. Indigo Buntings and Hooded Warblers have arrived.
3-27-08. This morning, I began the process of moving out of the house in Waveland and getting my stuff packed up and stored away. I have decided to stay for an extra day and plan to spend some time in the field during the next few days, but then I must head back to Virginia.
3-28-08. I took my final kayak ride of the season and visited the 2006 hot zone. The most interesting experience was a Barred Owl that flew right over and stared down at me. I tried to get it on the paddle-cam but missed. While in Tree 5 a few days ago, I saw lots of birds flying above the canopy. Based on video footage that I got during that climb, it now seems clear that birds use the tallest cypresses as landmarks to navigate through the Pearl. I noticed birds that seemed to be navigating using Tree 5 and two other tall cypresses that are well within camera range. It sure would be exciting to see an ivorybill flying directly towards me from a distance.
3-29-08. I hiked out to Tree 6 before dawn and spent several hours up there this morning. I intended to run the high-def camera, but a problem with moisture condensation forced me to revert to the standard camera. After about an hour, I noticed a large bird approaching from down the bayou and assumed it was a Wood Duck based on the fast flight. I nonchalantly tracked it with the video camera, thinking it would be interesting to get some footage of a Wood Duck from above. Just before the bird passed directly below, I saw two bold white dorsal stripes. I saw white trailing edges on the wings as the bird continued up the bayou beyond the observation tree. I didn’t have a chance to download and inspect the video today since I had to finish getting ready for the trip back to Virginia. I extended this search season to the very limit and must leave tomorrow. A discussion of the video footage that was obtained is available
3-30-08. Before packing up my computer for the trip back to Virginia, I took a quick look at the video from Tree 6. The video quality is poor since the camera focused on tree branches in the foreground, but
these frames are interesting. The top frame shows the underside of the bird reflected off the water (the bird itself was hidden behind vegetation at that point). The bottom frame (and other frames in that part of the video) appears to show a white trailing edge. The arrows indicate the direction of flight. The flap rate is about ten flaps per second. I hate to have to depart immediately after a sighting, but I extended the visit to the absolute limit. I have obligations in the D.C. office and need to get back to Virginia to renew my drivers license, which expires at the end of the month.
4-7-08. Dalcio Dacol has pointed out similarities between the bird in the new video and ivorybills in two Tanner photos. Several frames from the new video and images cropped from the Tanner photos are compared
The images in the left column are of the bird as it approached the tree. The first two images in the right column are of the reflection of the bird off the water just before the bird passed beneath the tree. The other two images in the right column are from the Tanner photos. Unlike the flight of a duck, the wings are brought in close to the body in the new video and in one of the Tanner photos. The tips of the wings appear to be swept back in the second and fourth images in the right column. The bird flew with about ten flaps per second and showed lots of white on the trailing edges of the wings. Although it passed beneath the tree very rapidly, I saw what appeared to be dorsal stripes. Tree 6 is within a kilometer of the 2006 hot zone, and the probable sighting on February 16 was only a short distance up the same waterway.
4-8-08. It has occurred to me that the bird in the new video was flying up the channel from the area where I found extensive foraging sign on January 17. It’s fortunate that the bird and its reflection off the water are both visible. The flap style is well resolved in a series of reflected images. The wings appear to be fully extended and very long in a few of these images. Images of the bird itself show the flap style and white trailing edges on the dorsal surfaces of the wings. There seems to be something amiss about the historical accounts of a duck-like flight by ivorybills. What I understand to be duck-like flaps doesn’t involve nearly closing the wings during each flap. Since nobody ever had the opportunity to study the details of the flaps of a cruising ivorybill in slow motion, it’s possible that the cruising flight wasn’t fully understood.
This clip (which is sampled at 120 frames per second and plays at quarter speed) shows the rowing flap style. The underside of the bird, which is visible as a reflection off the water, appears very dark just like the reflections of trees in
this image from the video. I’m now convinced that the bird in the video must be an ivorybill. What other species has white trailing edges, such a high flap rate, and a distinctive flap style that is consistent with the Tanner photo? I should have trusted my eyes when I saw the dorsal stripes, but it’s hard to be certain about something that happens so fast. When the raw video is viewed at full speed, it’s amazing how fast the bird flies below Tree 6.
4-9-08. An exciting aspect of the new video is that there are points of reference (such as tree branches) that should make it possible to return to the scene and determine the flight speed. This quantity has never been measured since the historical footage doesn’t show the cruising flight.
4-10-08. These images
show the white trailing edges through three frames that are spaced by 1/60 of a second. After the trip back to the Pearl, I’ll have some analysis to finish up on the new video. I’ll try to get the measurements that are required for computing the speed of the bird. I will also get better estimates of the flap rate, which varies throughout the flight.
4-11-08. I’ve come down with a bad cough but will try to get on the road to Louisiana this evening. Here are some images from the March 29 video that show the views
down the bayou,
nearly directly below, and
up the bayou.
4-12-08. I didn’t get started on the trip until this morning but made it well into Alabama.
4-13-08. I have arrived back in the Pearl.
4-14-08. I returned to Tree 6 and determined that the bird in the video flew approximately 81 meters in 5.5 seconds. This corresponds to a speed of about 33 mph, which is much slower than I would have guessed. I obtained this value from the ground. I plan to obtain a better estimate by taking images from the video up the tree.
4-15-08. Sitting at a stakeout isn’t my preferred approach for searching, especially while sick on a chilly and damp morning. Since the cough got worse, I spent the afternoon in bed.
4-16-08. I spent the morning at the stakeout. I found a place where I’m well hidden, the view down the channel is good, and I can sit comfortably for several hours.
4-17-08. This image shows the view looking down the channel from which the bird came on March 29.
This image shows the dark mud over which the bird flew on March 29. The dark leading edges of the wings would have been difficult to resolve against this background.
4-18-08. I spent another morning at the stakeout. There were a few Wood Duck flybys along the channel. I didn’t get an exact timing, but they seemed to cover the 81 meters between the two reference points in the March 29 video in less than 5.5 seconds (see April 14 comments), and the flaps weren’t at all like those of the bird in the March 29 video.
4-19-08. I spent another morning at the stakeout. It has been interesting to see the different birds that show up there everyday. There were lots of herons the first few days. This morning, I saw a pileated in that area for the first time. It seems likely that the ivorybill will pass through there again, but I’m running out of time. I’m planning to climb Tree 6 in order to get some measurements tomorrow.
4-20-08. A visitor hiked to the stakeout with me in order to help take measurements. Since the area is now flooded, it wasn’t possible to get the reference object in position without a kayak, but we did find lots of unusual woodpecker work on Tree 6 and other living cypresses, including
these examples. There are also several large cavities in the area. My allergies were bad, but it was a bayoutiful day.
4-21-08. After spending one last morning at the stakeout, I drove nearly halfway home this afternoon and evening.
4-23-08. On the 1042 mile drive back to Virginia, the Honda used only 26 gallons of gas (40.1 mpg).
4-25-08. Based on the flight speed of the bird in the March 29 video, it only takes two minutes for an ivorybill to fly a mile. Due to all the fallen trees, thick vegetation, and muddy sloughs in the Pearl, it can easily take five hours for a two-way “death march” over such a distance. This gives an idea of the advantage these birds have over a hapless human trying to find them.
5-1-08. A leading expert on the flight mechanics of birds is analyzing the March 29 video. He is “confident that it is a large woodpecker” The expert also noted “considerable white (or light gray) visible on the upper surface of the wings” and mentioned that “those patches of light-colored feathers would seem to be consistent with an IBWO.” The expert also noticed “pauses in mid-upstroke during which the bird holds its wings flexed in a bound posture.” This wing-tucking behavior is well known in other woodpeckers but had never been reported for IBWO. The expert pointed out that “observers of a live bird in the field (e.g. Tanner) would likely miss” this aspect of ivorybill flight since the flaps are so rapid and the tucking is much briefer than in other species.
5-22-08. At an applied mathematics conference this week,
I gave a talk on “Physics of an Avian Controversy” in a session on mathematical biology and presented the expert’s comments on the
March 29 video. In such a setting, it wouldn’t have been appropriate to mention comments from an anonymous expert, but Bret Tobalske gave me permission to disclose the fact that he has analyzed the data.
6-1-08. I have used GPS coordinates to determine that Tree 6 is 600 meters from the 2006 hot zone, 840 meters from the tree in which the bird appears
perched in the 2006 video, and 300 meters from the area where I found extensive foraging sign earlier this year (the bird in the 2008 video was flying from that direction).
6-14-08. I have returned to the Pearl for a brief visit. As of the first gas stop during the drive from Virginia, the non-hybrid Honda was getting 42.8 mpg (424 miles on 9.91 gallons).
6-15-08. After dragging a pirogue loaded with climbing gear more than a mile to Tree 6, I barely had enough energy left for the climb. Using images from the video, I guided Gretchen to various positions on the water, where she drove marker stakes into the mud. It turns out that the flight speed (which we measured over two segments) is a little greater than the crude estimate that I obtained from the ground in April. We used the laser rangefinder to determine that the camera was about 80 feet above the water; we double checked this measurement using a line loaded with a lead weight.
6-17-08. Two visitors joined me for some exploring in the general area of the recent sightings. Before the visitors arrived, I came upon at least twenty Swallow-tailed Kites, including
this group. Later on, we encountered other cooperative subjects, such as this Mississippi Kite and
6-18-08. Dave from Michigan and Mac from Alabama joined me for a visit to Tree 6, where we took some additional measurements. While up top, I got a photo of a
Mississippi Kite that flew by at close range.
On the way down, I got a photo of
this unfinished cavity (there are several others like it in the area).
6-20-08. Dave from Michigan joined me on a long hike, and we saw a velvet ant, which is actually a wingless wasp with a potent sting.
6-21-08. I spent the morning down near Tree 6. I saw two adult Swallow-tailed Kites dive bomb a juvenile. One of them swooped so aggressively that there was a loud sound from the wings. On the way out, I saw a huge wild hog and heard a Swainson’s Warbler singing.
6-22-08. While at Tree 6 yesterday, I took photos looking
downstream and upstream. Tree 6 is the cypress with a low branch extending out over the water. Two stakes that mark positions of the bird are visible in the upstream photo.
6-23-08. It was a beautiful morning in the swamp. On the way in, I flushed a turkey less than ten feet away. It was quite impressive to see and hear it explode into flight. On the way out, I saw a bobcat. I had previously seen jaguar and mountain lion tracks, but this was my first sighting of a cat in the wild. It was in an area with a large population of rabbits.
6-24-08. Mark from New York is in for a visit. I showed him around the 2006 and 2008 hot zones. We covered about eight miles on foot and four miles on the water. It was my first time in the kayak since the end of March. Mark found some interesting foraging sign near where I had my first sighting in 2006. I found what appear to be bobcat tracks far from the location of the sighting yesterday. There has been a lot of pileated drumming the past few days.
6-25-08. Mark and I covered a lot of ground again this morning. We did some exploring on a trail that I had never tried and found that the habitat is degraded. We tried to do some exploring in another area, but the vegetation was too thick. During the hike yesterday, I obtained photos of this
buttonbush and this paw print.
6-26-08. It was a nice morning out in the swamp. Since my legs were a little sore from the recent hiking, I decided to do a stakeout at Tree 6, where I saw this butterfly, which Jonny Kemp identified as a female Spicebush Swallowtail. Lots of rotten wood has been falling recently. On the way to Tree 6, a medium-sized tree came crashing down just up the trail. This recent fall contains an old cavity.
6-27-08. It was a grueling day in the Pearl. This morning, I did a stakeout at Tree 6. This afternoon, Gretchen and I waded nearly a kilometer into the swamp to Tree 0. There are so many big trees in that grove that it took a while to find the right one after we had navigated to within 100 meters. Since the previous visit on February 10, vines grew about 25 feet up both sides of the rigging line. Gretchen climbed to the top, while I took it easy down below.
In this panorama of Tree 0, Gretchen is barely visible about 100 feet up. Although the view was limited by the surrounding trees, I got the laser on one of the branches near the top, and it was over 100 feet. We encountered several snakes on the way back.
6-28-08. The time has come to return to Virginia. It was a successful visit since I was able to pin down the wingspan and flight speed of the bird in the March 29 video. I thank Gretchen and Dave for the help in taking those measurements. It was also nice to have Mac and Mark in for visits during this trip to the Pearl.
6-29-08. I have arrived back home in Virginia. The Honda got 41.5 mpg despite several major traffic jams.
A day-to-day log of the 2009 search season is posted here.