Recent Ivory-billed Woodpecker Evidence Shows Never Before Seen Behavior: Courtship Mating and Sky Pointing
F. Virrazzi DRAFT
The three featured main frames and their representations show Ivory-billed Woodpecker, Campephilus principalis, behaviors previously undescribed in the literature. These long missing observations of the early reproductive activities of the Ivory-billed are found in the supporting on-line material (SOM) of the paper:
Ivory-billed Woodpecker (preprint paper 2022, Latta, et al.)
Full Title:
Multiple lines of evidence indicate survival of the Ivory-billed Woodpecker in Louisiana 2022Steven C. Latta, Mark A. Michaels, Don Scheifler, Thomas C. Michot, Peggy L. Shrum, Patricia Johnson, Jay Tischendorf, Michael Weeks, John Trochet, Bob Ford
The specie's original and first description was in the early 1700's by Catesby.
The eventual rarity of the species, minimal interest in behavior, increasing wariness of the species combined with arboreal habits and the difficulty of viewing pairs before nesting contributed to the late discovery of the behaviors described here. However the literature is extensive, published over centuries and sometimes not easily accessed; a review has been in progress for months confirming facts in this article.
These courting behaviors and actual copulation appear in the game camera stills, video compilation, but are not described in the recent preprint, 2022 paper. The exact images can be found in the paper's SOM S1 SI Video Compilation Louisiana . Because of their potential importance in relation to specie's identification and conservation implications (viable species) they must have been overlooked by the busy authors or not recognized.
Sky pointing or a similar behavior has been observed in hundreds of bird species if not more. Sky pointing is often used to refer to Booby (family Sulidae) breeding behavior. The phrase is somewhat inarticulate; with the pointing including other movements and the reason for the behavior having various functions in different species.
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| Two consecutive frame representations, of different frames, both showing Sky Pointing, notice males right wing ventral surface is showing with black central area of IB underwing showing in one frame but not the other. Ventral wing underside cannot be seen when folded. Female also shows possible white wing parts in lower body in both frames. |
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| Two Consecutive and Different Frames, both showing Sky Pointing, Notice Males Right Wing Ventral Surface is Showing with Black Central Area of IB Wing Showing in 1 Frame but not Other. Ventral Wing Impossible to be Seen if Folded. Female also Shows Possible White Wing Parts in Lower Body in Both Frames. |
Courtship rituals of some species include sky pointing which involves both the male and female erecting their bills and necks in a vertical position; this behavior can be repeated or preceded or followed by clasping, pair bonding and/or copulation.
Here we have two very large woodpeckers; upon finding this game cam scene the possible sky pointing was noticed but the chance it was predator recognition behavior rather than part of a ritualized mating sequence, was a primary possible explanation. The key frames of the compilation video start at 12:27:01 PM 11/30/19.
The female is obviously on the left; male on the right. The bull is massive and is noticeably larger than the female. There is sexual dimorphism in both large woodpecker species extant in the USA. The absolute size difference in Ivory-bills is greater than in Pileated (PIWO). The disparity between these two perched birds is excessive for Pileated; it better fits Ivory-billed, however it's difficult to confirm sizes without 3 D software or further work.
The prior frame to the pointing was odd and studying it briefly showed a wing pointing out to the right but the flight feathers produced a narrow chord which seems insufficient to involve take off or the first few feet of a flight from the nearby trunk. During flight initiation an Ivory-billed and most large birds will have flared out outer primaries and outstretched wings to maximize lift.
Wing beat frequency should also be relatively high for the respective species. There should also be a drop in altitude from the trunk lift off spot to the position of the captured mating. We see no evidence of this; there is no wing blur nor drop in altitude noted.
However the wing is captured mostly edge on so flaring is possible but not in combination with the approximate 90 degree angle of the phalanges to the humerus. During takeoff or early flight the intraskeletal angle of these respective bones should be more obtuse since the feather must be spread to increase lift. This is not seen in the subject frame.
There were also a few areas of white plumage. But the potential usual identification clues in the other 150 unseen S1 frames was more on my mind for immediate review.
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| In hundreds of prior and subsequent frames there are often two or three IBWOs (Latta, et al.). Then two birds are "missing" in a frame and this unusual mass of birds, if not mating is there. The next two frames show sky pointing which is often associated with mating in various species of birds. The three frames are completely compatible with courting and mating along with the date and postion in the tree. |
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| Female body outline (pink) and male body outline (blue). Dash pink line represents position of female's body, pressed from behind, and against an ~ 7 inch branch stub. |
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| Similar to prior female and male diagram frame and but slightly different position of female |
I soon reached out to thousands of almost exclusively casual readers on these frames many without video software and received minimal feedback: "it's extinct", "it's intriguing", "we are reviewing" " I will look", "incredible", "wow" and "let's meet over a shared screen to examine it".
After reviewing the frame compilation video no overhead predator was found; attention returned to sky pointing as part of possible ritualized behavior.
The odd, previous frame was revisited in the context of the breeding implications of the sky pointing; it now made sense---it's two Ivory-bills mating in this unique frame. The hen and male had met on the branch with the impressive red-head; the bull flipped partially upside down under the female's raised torso where he is mainly unseen except for the distal half of his wings and most of the tail.
Some large woodpeckers are known to mate on horizontal branches including PIWO. Kilham noted 16 copulations; the females however "squatted cross- wise" on the branch not parallel like the subject frame.
On S1 the female is more parallel to the branch orientation than cross-wise as directly observed for Pileateds. Females will lay their head and neck prone on the branch likely to center or anchor some weight there since it must thrust its lower body up in the air to let the male transfer the sperm via a cloacal kiss. The vents in birds may only be together for a few seconds. This particular mating is over in less than 10 seconds. Frames are separated by 5 seconds in the game cam compilation video.
The male clings sideways from the ventral side of the female. It's left, far wing can be seen thrust out pointing to the right seemingly just suspended with no critical purpose but it may be acting as a counterbalance to the female's weight. The right, closer wing is under the female resting on the branch; it could be functioning as an anchor held there by the female's mass.
Notice the left wings long narrow profile with no indication of wing blur but just camera limitations. It is very unlikely this wing was flapping. The wing is very narrow and pointed; more so than a Pileated's should show. The inner chord is also comparatively narrow for a Pileated; the bird has a long aspect ratio similar to an Ivory-billed. I believe if carefully measured and studied with 3D software this left wing could further confirm this bird as an Ivory-billed.
The former paragraph seems to be the probable position in the mating frame. The right wing may also be over the neck of the female, the wing protruding down as it comes into view at its distal tip right at the bottom branch edge.
The birds are on ~ 8 inch wide, curved branch and their vents must meet; there are a limited number of possible positions.
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| Female's neck and chin likely down on the branch, pointing left. Notice white shield with suggestion of dark split in middle as in IBs. Male is ventral side up, beneath her, left wing pointing towards trunk. Wing seems to show white outer edges and black center. Right wing's dorsal surface laying on branch, ventral side of wing showing white on the leading edge, and suggestion of trailing white edge and black midwing. Vents are lined up. Mating pair; also supported by evidence in the next two frames (sky pointing) and many prior frames where they gradually approach each other over minutes with minimal or no foraging or excavating |
There are one or more observations by Kilham after several hundred hours where a Pileateds is described as pointing its bill and neck upwards even backwards. This can be called sky pointing; however neither species of large USA woodpecker may be known to exhibit it in November inclusive of thousands of hours of observations on Pileated highlighted here. The Ivory-billed is the least studied Picidae of any in the United States; it is the most likely species to have new behaviors discovered in any novel game cam sequence of thirty minutes in November. Certainly this footage took many months of hard work by D.
Pileated Woodpeckers have been observed tens of millions of times with a satisfactory collection of life history and breeding phenology literature.
Pileated pairs are known to wag their bills and dance before mating. The dance consists of one bird bowing, scraping, and stepping sideways in a circle around the other bird. Their bill's angle to the ground is infrequently or rarely more than 45 degrees. Video of Pileateds on the Ground pileateds Ivory-bills are known to bill clasp which in other species can be sequenced with sky pointing.
This long exert taken from the 570 page classic, Birds of Kentucky is just one of the hundreds of references on when Pileateds breed:
A review of Campephilus literature may shed some light on the courting behavior of congenerics.
Note that bird mating normally requires several seconds to complete and the hen is sedentary; this proved to be an unusual "opportunity" for the camera to catch still birds, unlike many other frames where birds are moving to various degrees in this fantastic work by the Louisiana team of ten. The white shield and even the suggestion of the center black "wing gap" is seen. The upper shield and upper body of the female is likely occluded by a raised area or vertical knot of the tree branch. The branch anomaly coincidentally looks like a bill and neck. The females head and neck are on the far side of this knot and likely would appear like the above female-male representation. In large woodpecker species the female on the branch agrees with Picidae literature that notes they lay their neck and bill on a branch.
This is a complex behavior involving two birds hypothetically providing the opportunity to see more field marks than a one bird frame would. And this frame delivers. There is no other frame like this in the preprint and it contains two birds; the two birds were on the tree trunk, arrived on the close branch, morphed into a tangle of birds inches from where the male and female sky point ~ 5 and 10 sec after the mating.
Although the birds are poorly resolved they spatially match where the birds' relative position of the bodies would be, must be, to copulate. After they break apart the smaller female moves to the left and with the male, both sky pointing for two consecutive frames.
For the 60 frames, 5 minutes, before the mating the two birds slowly get closer to each other on the left side of the tree trunk approaching to within 2 feet of each other before they move to the nuptial branch. During these 5 minutes the birds often have their head away from the trunk; foraging is not prevalent. They are interacting with each other; it is assumed that at least the latter part of this 5 mins the birds are somehow communicating with each other their desire to mate.
To get a complex behavior like this portrayed and argue it is produced by artifacts or is poorly resolved will require explanations. The other hypotheses have been examined and for them to look like mating but are in fact not be mating of large woodpeckers relies on implausible and unreasonable assertions.
The other frames of S1 clearly show there are three very large woodpeckers in the tree. The literature for IBWO indicates that three Ivory-bills is the most common group number one should encounter for undisturbed, foraging Ivory-bills captured by a game cam in late November.
Pileateds are territorial, unlike the Ivory-billed, and a mated pair almost always chases away the year's young by October, S1 was captured in late November, 2019. PIWO Disperse September
Next the date of the sky pointing and mating is to my knowledge unprecedented or at least early for Pileated and indeed must be explained without the usual highly improbable to impossible explanations that seem to crop up.
Of course a simple explanation could be that Pileateds do occasionally mate in November. If true it must have been observed for this common and well studied species. This has been examined. Pileated Courtship Feb to April . Mating occurs in April according to some references PIWO April Mating . In this reference nesting is in June Pileated nesting in June This reputable source says mating can begin in late March PIWO Mate Late March
Early egg dates in the southern U.S. for PIWO is in early March; late egg dates, from northern areas, are in mid-June.
30 November 2019 fits the Ivory-billed breeding phenology much better, which is known to lay eggs as early as January. Since it only takes 2 days for birds to form eggs this mating behavior strongly infers that females have the ability to store viable sperm for at least 30 days.
Perhaps there has been some microevolution driven by the decreased selection of unrelated mates per time unit. Sperm storage tubules may have expanded their annual circadian activity resulting in an earlier start of the breeding phenology. Resultant could be a more viable genome as these tubules are know to select fitter sperm in other species.
Any hypothetical sperm storage tubule expansion in temporal activity may incrementally help explain the utterly surprising, and totally impossible to some, tenacity and existence of this species.
The camera capture of a copulation is a seminal event; it shows some level of fitness.
The 2022 Ivory-billed evidence from Louisiana does not support the hypothesis that species is extinct; the frames highlighted here support the species has a level of fitness although not quantified. It's well past the time to accept that one of our greatest natural resources persists.
Acknowledgments: NBP wishes to thank all the Ivory-billed field researchers and Emile DeVito PhD, ecologist. Ms. Tara Dattoli our biologist and artist, Mr. Chuck Hunter, biologist, Mark Graham, GIS specialist, Ms, Tammy Kempf, Mr. Jeff Jotz, administrator and Fred Virrazzi, zoologist for their selfless contributions towards this research.
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