Kāma'o (Myadestes myadestinus) pronounced extinct

 

M. myadestinus taxidermy specimen from the Bishop Museum, Honolulu. Retrieved via Wikimedia Commons. CC0

I usually enjoy returning to old topics with new information, but in this case I wish I wasn't. Readers will recall that I previously wrote a post on the lost solitaires of the Hawaiian islands back in 2016. At that time, the kāma'o, an endemic Hawaiian thrush, was still officially considered Critically Endangered by the IUCN. After not being spotted since at least 1989, however, the official pronouncement of its extinction was really only a formality.

I doubt that many people took note when this bird was included on the US Fish and Wildlife Service's memo on 29 September 2021, where it and 22 other organisms were proposed for de-listing from the endangered species rolls due to extinction. The ivory-billed woodpecker (Campephilus principalis) was also on that list, and predictably it got all the headlines.

I'd like to call attention not to the ivory-billed woodpecker, but to a troubling metric seen on that memo: the fact that of those 23 species, nearly half are species endemic to Guam and Hawaii. We still understand so little about the species that we're losing in these Pacific island ecosystems, and I worry that as long as people focus their time and energy chasing woodpeckers that probably aren't there, we risk losing even more of our planet's amazing species - not just birds - that might not be as large or as charismatic, but which are every bit as important. As our planet faces a climate crisis with unforeseeable consequences, I only hope that people who are passionate about the natural world and conservation will find room in their hearts for birds like the small thrushes of the Hawaiian islands, which still need all the help we can give them.

I'd hate to end my first post in a couple of years on such a gloomy note. There's a lot more in the pipeline for this blog in the near future, including a review of the amazing Apple TV series Prehistoric Planet, which should be coming along in the next couple of days. Thank you for your patience!

Oxyurin Odyssey

A selection of members of Oxyurini. Clockwise: Black-headed duck (Heteronetta atricapilla) drake and hen in Rio Grande do Sul, Brazil; Masked duck (Nomonyx dominicus) drakes in Tobago; Ruddy duck (Oxyura jamaicensis) drakes in South Dakota; Maccoa duck (O. maccoa) hen at the San Diego Zoo. All images are retrieved from Wikimedia Commons.

So, waterfowl. You might take your neighborhood mallards for granted as I often have, but waterfowl are really very cool. Yes, even the endless hordes of Canada geese blocking your commute, disgruntled American readers. The order Anseriformes contains something like 180 extant species, and just about all of them are outright fascinating. Today we'll zero in on a small clan of anatids known variously as the oxyurins, oxyurines, or the stiff-tailed ducks. Exactly which of these three names is best for this group is a little ambiguous. "Stiff-tailed ducks" may well be reserved for the members of the type genus Oxyura, and the entirely superfluous debate over whether they represent a "tribe" or a "subfamily" informs the rest. I'll be calling them oxyurins throughout this post for convenience's sake, irrespective of long-defunct Linnaean concerns.

Traits, Position and History

Oxyurins are so-named for the stiff, upward-pointing tail feathers just about all of them share. They're small, compact ducks, usually ranging between 30 and 55 cm (11.8 to 21.6 inches) in full body length; compare with the widespread mallard duck (Anas platyrhynchos) and its 65 cm (25.6 inches). Like the distantly related aythyin ducks, oxyurins are divers, and as such are built with back-set feet which force them to move awkwardly on land. In fact, this condition is more pronounced in this tribe than in any other sort of waterfowl. Ungainly though they are on land, they're all highly competent in the water, appearing almost exclusively in freshwater environments. Almost all species share distinctive blue coloration in the bill in males, bar the black-headed duck (Heteronetta atricapilla). This deviation is unsurprising, because Heteronetta is undoubtedly the basalmost member of this clade. Often included in Oyxurini but excluded here is the musk duck (Biziura lobata) of Australia. This is a little controversial, and many would still include this duck and its notably stiff tail with the oxyurins. More infrequently included is the white-headed duck (Thalassornis leuconotus), another weird Australian duck. Increasing genetic evidence has removed these two Australian species from the oxyurin fold, showing Biziura to be just a short distance outside of the oxyurins and Thalassornis at a position basal to almost the entire anatid family. Another surprise modern genetic analyses have uncovered for us is the fact that Oxyurini is part of the anserine subfamily. The fact that these "ducks" are far closer to geese and swans than they are to the more familiar anatines so common worldwide is somewhat underappreciated, I think; it's difficult to see this just based on gross morphology, so it's a small wonder that, for a very long time, oxyurins were thought to group with most other "ducks".

Relationships of anatid subfamilies and tribes, as per jboyd.net.

Today there are eight (ish) oxyurin species in three genera. The aforementioned black-headed duck is the only member of its genus, as is the masked duck (Nomonyx dominicus). The remaining six species are all members of the eponymous genus Oxyura. The black-headed duck is restricted to southern South America while the masked duck ranges out of South America and into Mexico and the Caribbean. Members of Oxyura, however, can be found on every continent but Antarctica. The tribe (unsurprisingly) sports a few more among its number once you go back in time. The most recent losses to this clan are all species of Oxyura, the most notable of these being the New Zealand stiff-tailed duck (O. vantetsi). The extinction of this species some time before 1600 CE marked the extirpation of the oxyurins from New Zealand. Closely related to Australia's blue-billed duck (O. australis), the New Zealand stiff-tail was even smaller than this already quite runty waterfowl, but little else is known for sure about it.

The ranges of the various Oxyura species. Yellow: Ruddy duck (O. jamaicensis). Red: Lake duck (O. vittata). Green: Maccoa duck (O. maccoa). Dark blue: Blue-billed duck (O. australis). Light blue: White-headed duck (O. leucocephala). Retrieved from Wikimedia Commons.

A few other fossil species have been assigned to Oxyura, but only O. zapatanima of the Pleistocene of Jalisco, Mexico appears to unambiguously represent a valid example. Further back, the fossil taxon Lavadytis pyrenae from the Miocene of Nevada seems to pin the New World as a major origin point for many oxyurin species, which isn't surprising when you consider that the Americas have the greatest diversity of them. Other extinct taxa like Mionetta and Tirarinetta, which might be oxyurins, suggest that they had their genesis in the Oligocene and rapidly diversified around the time of the Miocene Thermal Optimum. (Also, the Lavadytis paper seems to recover the lake duck [Oxyura vittata] as sister to a clade including all other Oxyura species, but also Nomonyx. Anatid taxonomy is a mess.)

The Ways of the Cuckoo Duck

With the cladograms safely tucked away, we can talk a little more about the varied lifestyles of the stiff-tailed ducks. One of the most-noted talking points about oxyurins are the egg-laying habits of the black-headed duck (Heteronetta atricapilla). A small bird with a vaguely spatulate bill, the black-headed duck is, as discussed above, the basalmost member of its tribe and in many gross details more closely resembles dabbling ducks than its more specialized relatives. Thanks in part to an excellent David Attenborough documentary segment called "Nature of the cuckoo duck", the black-headed duck's status as the only obligatory brood parasite among the world's waterfowl has made it of significant biological interest. For those not tapped in on the terminology, what this means is that the black-headed duck never makes its own nests, and must seek out those of other birds in which to slip its eggs in order to propagate. This is what has earned this remarkable little duck its nickname.

A black-headed duck photographed near Trelew, Argentina by Gustavo Fernando Durán.

Rather than achieving perfect mimicry of another species in their eggs as many brood parasites do, the black-headed duck appears to have made up for it in sheer breadth. Its eggs have been discovered in the nests of many other species, including other waterfowl, coots, gulls, and even harriers! They must be fearless indeed to approach the nests of birds of prey (or, more likely, they can't tell the difference). Since oxyurin ducklings are highly precocial and are capable of wandering off on their own shortly after birth, they don't belabor their adoptive parents too long and strike out into the world in very short order. Interestingly, the literature reports some other alleged cases of brood parasitism in other oxyurins, including the blue-billed duck (Oxyura australis), but no serious research seems to have been committed to this matter. Whether the "cuckoo duck" is really unique among the oxyurins in this respect remains to be seen. In either case, it's no less charming.

The Amazing Whatsit of the Lake Duck

And now to the awkward bit. Like it or not, along with feeding, reproduction is one of the most essential biological functions in nature. If you're not keen on this special brand of scientific enlightenment, then you're welcome to skip forward to the next section. I won't judge you (but the ducks might).

A lake duck, displaying the awkward gait typical of oxyurins, at the Wuppertal Zoo in Wuppertal, North Rhine-Westphalia, Germany. Photographed by Georg Sander.

The reproductive equipment of oxyurins is remarkable, even among ducks. The "whatsit" in question here is the male reproductive organ, the fair and balanced term for which is, in this context, the "intromittent organ", not "penis". This is because, as far as we can tell, the intromittent organs of birds and reptiles aren't homologous with those of mammals - that is to say, they don't share a common evolutionary origin and apparently were developed separately. It's worth noting that most male birds don't have such organs; something like 97% of all avian species reproduce by way of a "cloacal kiss", where the openings of the birds are pressed together for a transfer of semen. The only birds that have retained their intromittent organs, as their closest living relatives (the crocodilians) do, are the basalmost bird clades, including galloanserans and palaeognaths. This in itself has implications for the reproductive habits of non-avian dinosaurs, but that's a post for another day.

At any rate, other ducks have particularly prominent and oversized intromittent organs, but male oxyurins take it to another level. Most famous of these is the lake duck (Oxyura vittata), the intromittent organs of which have been measured in excess of 40 cm (15.75 inches), or almost the length of its entire body (!), though they usually seem to measure in at a "mere" half of that. This gives the lake duck the honor of having the largest reproductive organ-to-body ratio of any vertebrate. That being said, it does seem to get a disproportionate amount of press for this distinction, because other oxyurins also have rather large intromittent organs. Studies have indicated that the size of these organs varies so widely in response to environmental factors, chief among which appears to be competition between males. When in an environment in which more male ducks than females can be found, their average sizes becomes far greater. Oxyurin phalluses notably sport a set of brush-like bristles at the tip, a bizarre little adaptation which seems to serve some role in removing the material of competing males from prospective mates. They also all share the same shape, that of a counterclockwise corkscrew which unfurls when in use, one which is shared by some other waterfowl.

Interestingly, female ducks of this tribe (and a few others) likewise host their own elaborate corkscrews in their internal anatomy, but these run clockwise, opposite to their male counterparts. This seems to pose a means of thwarting penetration by male ducks, a serious concern in a type of bird which practices forced copulation at an alarmingly high rate. Between these bizarre mechanisms and the seemingly ultraflexible sexual anatomy of male oxyurins, it's clear to see how the highly promiscuous habits of these little ducks are a driving force in their reproductive evolution.

The Magnificent Butterball

So, let's move on to less shocking territory and spend a moment focusing on my personal favorite of the group, the ruddy duck (Oxyura jamaicensis). In some parts of the USA, it's apparently sometimes called the "butterball", which is just so impossibly charming that I feel obliged to mention it at least twice. A handsome little duck of about 38 cm (15 inches), in the North American part of its range it's instantly recognizable when compared to conterminous waterfowl, thanks to its bright blue beak, "bumblebee" wing beat, and diminutive size. It ranges widely across North America (including the author's native Ohio, where I've spotted the funny little birds in local wetlands on a couple of occasions), and also into South America. Its populations there (including the Andean duck O. j. ferruginea) are sometimes regarded as separate, but the popular mood among ornithologists now seems to be to treat them as part of the ruddy duck assemblage rather than distinct species. Interestingly, the ruddy duck has also been introduced to Europe, whether purposefully or accidentally by bird collectors, and has caused significant concern by competing and apparently even interbreeding with the endangered white-headed duck (O. leucocephala). Once hosted in the British Isles in the thousands, recent culling efforts have reduced their number to no more than a hundred individuals, seeming to spell an end to this species' European adventure.

Ruddy duck drake in flight. Photographed at the Benton Lake National Wildlife Refuge, Montana, by Neil Mishler (USFWS).

Despite its unwelcome appearance abroad, the ruddy duck remains popular with birders in North America, thanks to its striking appearance and amusingly bold behavior in the breeding season, as well as the odd "bubbling" displays males put on when displaying. The naturalist John Charles Phillips sounds almost charmed by its idiosyncrasies when he writes of the bird in his 1926 work on waterfowl, “Its intimate habits, its stupidity, its curious nesting customs and ludicrous courtship performance place it in a niche by itself…. Everything about this bird is interesting to the naturalist, but almost nothing about it is interesting to the sportsman.” The name "butterball" apparently derives from the almost round shape of the bird when prepared to cook, which certainly lacks the cuddly connotations implied by the alias. Although it has a bad reputation among some hunters as a "trash duck" on account of its diving habits, it was regarded as a delicacy a century ago, and it still has its fans today. Less amenable to ruddy ducks are grebes, with whom they occasionally compete for living space and food; grebes have even been observed to aggressively attack ruddy ducks at some times of the year, even pursuing and pecking at them from underwater where most other animals can't touch them. It's easy to see a bit of karmic justice in this, when you consider that ruddies themselves chase other animals during the breeding season, including other ruddies, different waterfowl, and even rabbits, apparently out of pure pique (or pure testosterone). But needless to say, it's just the way of the wild. It certainly adds to their long list of idiosyncrasies and makes them all that much more likable.

Onward Oxyurins

And so we come to the end of our odyssey and reflect. The charm and scientific depth of these birds certainly makes them worthy of our attention, and as we've seen, some facts about them have become rather well known to general audiences, and not just the scientifically inclined. Still, in the course of doing my research on the stiff-tailed ducks, I discovered that many of the novelties with which we credit individual species are apparently shared among the other members of the group, but ignored or less well-researched. There's certainly a lot more about these ducks that's interesting, but which I just didn't have the time or space to cover here. I encourage anyone interested in waterfowl in particular, or wildlife in general, to go out and do their own reading. Many of the sources mentioned below were very illustrative and led the way to other resources on the subject. And better still, the stiff-tails are practically everywhere; if you get a chance, go out and see some for yourself.

Sources:

• All About Birds. Ruddy Duck. Retrieved on 12/12/17.
• Alvarez, Rafael. "A Pleistocene avifauna from Jalisco, Mexico". Contributions from the Museum of Paleontology, the University of Michigan 24.19 (1977): 205-220.
• Attiwill, A. R. "Possible nest-parasitism in the Australian stiff-tailed ducks (Anatidae: Oxyurini)." Emu 81.1 (1981): 41-42.
• Birkhead, Tim R., and Patricia Brennan. "Elaborate vaginas and long phalli: post-copulatory sexual selection in birds." Biologist 56.1 (2009): 34-38.
• Boyd, John H. III. "TiF Checklist, Anseriformes". Retrieved on 12/12/2017.
• Brennan, Patricia LR, et al. "Coevolution of male and female genital morphology in waterfowl." PLoS one 2.5 (2007): e418.
• Cabrera, María B., Diego Montalti, and Luciano N. Segura. "Breeding phenology and new host list of the black-headed duck (Heteronetta atricapilla) in argentina." The Wilson Journal of Ornithology 129.2 (2017): 311-316.
• Guthrie, Daniel A. "Avian material from Rancho del Oro, a Pleistocene locality in San Diego County, California." Bulletin, Southern California Academy of Sciences 109.1 (2010): 1-7.
• Johnsgard, Paul A. "Handbook of waterfowl behavior." Handbook of Waterfowl Behavior, by Paul Johnsgard (1965): 7.
• Johnsgard, Paul A., and Montserrat Carbonell. Ruddy Ducks & Other Stifftails: Their Behavior and Biology. University of Oklahoma Press, 2010.
• Johnsgard, Paul A. "Waterfowl of North America: STIFF-TAILED DUCKS Tribe Oxyurini." Waterfowl of North America, Revised Edition (2010) (2010): 14.
• Livezey, Bradley C. "Phylogeny and comparative ecology of stiff-tailed ducks (Anatidae: Oxyurini)." The Wilson Bulletin (1995): 214-234.
• Maxmen, Amy. "Sexual competition among ducks wreaks havoc on penis size." Nature 549.7673 (2017): 443-444.
• McCracken, Kevin G. "The 20-cm spiny penis of the Argentine Lake Duck (Oxyura vittata)." The Auk 117.3 (2000): 820-825.
• Shaw, Hank. "Ruddy Ducks: The Original Butterball Turkey", The Atlantic. Retrieved on 12/12/17.
• Stidham, Thomas A., and Richard P. Hilton. "New data on stiff‐tailed duck evolution and dispersal from a new species of diving duck (Anseriformes: Anatidae: cf. Oxyurinae) from the Miocene High Rock Caldera in north‐west Nevada, USA." Papers in Palaeontology 2.1 (2016): 41-58.
• Worthy, Trevor H., and Michael SY Lee. "Affinities of Miocene waterfowl (Anatidae: Manuherikia, Dunstanetta and Miotadorna) from the St Bathans Fauna, New Zealand." Palaeontology 51.3 (2008): 677-708.
• Worthy, Trevor Henry. Tertiary fossil waterfowl (Aves: anseriformes) of Australia and New Zealand. Diss. 2008.

Lost Solitaires of the Hawaiian Islands

Three Hawaiian solitaires. Top to bottom: Kāma'o (Myadestes myadestinus), Oloma'o (M. lanaiensis), and Ōma'o (M. obscurus). Illustrated by John Gerrard Keulemans between 1893 and 1900. Retrieved via Wikimedia Commons.

In terms of the world's most biodiverse regions, the Hawaiian islands of the central Pacific have had a spectacularly bad run of luck over the past ten centuries. As with many of the world's oceanic islands, the Hawaiian Archipelago, some 2,500 miles (4,000 km) away from the nearest continental landmass, is home to numerous endemic species, including plants, invertebrates, and birds. With hunting and the introduced Polynesian rat (Rattus exulans) arriving on the archipelago with the first human settlement (between about 500 and 1300 CE), a number of ground-dwelling birds with vulnerable nesting sites, such as the massive moa-nalo waterbirds, disappeared. Later European exploration, conquest, and settlement on the islands brought a host of introduced Old World and New World species alike, which visited further devastation still on Hawaii's endemic species. Mammals like mongooses, pigs, and cats (and the Toxoplasma bacteria carried by the latter, which alone has devastated many native species) have wreaked untold havoc, especially on the native bird life. Only six passerine lineages seem to have made it to Hawaii in its history. Of these, one (Mohoidae, the Hawaiian honeyeaters) is now entirely extinct, the only avian family to have become so in the modern era. Another, Hawaii's sole native corvid, the Hawaiian crow or 'alalā, is currently extinct in the wild and persists only in captivity. Of Hawaii's two sylviids ("Old World warblers") one is extinct and another critically endangered. Even out of the largest of the endemic passerine groups, the Hawaiian honeycreepers (fringillid finches of the subfamily Carduelinae), a great number of species are either extinct or in danger of extinction. Hawaii's three monarch flycatcher species (Monarchidae) seem to have fared the best, by contrast, but on the whole it wouldn't be too great an exaggeration to say that all of Hawaii's native songbirds are in dire straits indeed. But more on these other groups another day - the sixth lineage is comprised of Hawaii's five thrushes, which will be the focus of today's post.

For a long time, the Hawaiian thrushes were grouped together in the unique genus Phaeornis, but closer analysis has instead borne out the conclusion that they are nested within Myadestes, the solitaires. American readers might be familiar with this genus in the form of Townsend's solitaire (M. townsendi), or Mexican readers with the brown-backed solitaire (M. occidentalis). Other members of this clade are found in the Caribbean, Central America, and into South America as far south as Bolivia. The solitaires' closest relatives are the bluebirds (Sialia) and, more distantly, West African thrushes in the genus Neocossyphus. It seems likely that Neocossyphus thrushes disseminated across the Atlantic Ocean from within the ancestral Neocossyphus-Myadestes-Sialia clade, given that the Myadestes solitaires crossed the Pacific to Hawaii in a similar fashion. Thrushes at large seem to have emerged sometime in the late Miocene epoch (most likely between 11.6 - 7.5 Ma) when they diverged from the Old World flycatchers and kin, Muscicapidae. This seems to imply that thrushes are ancestrally an Old World lineage and, if so, that they invaded the Americas on three separate occasions - the solitaires and bluebirds, Catharus and allies, and several species of Turdus and relatives. (And, further, that if the assumption about Neocossyphus crossing the Atlantic is correct, that the thrushes emerged in Afro-Eurasia, migrated to the Americas... and then migrated to Afro-Eurasia again.)

Relationships between the solitaires of Mexico, Central America, the Caribbean, and Hawaii - two interpretations. After Klicka et al. (2005).

From whichever stock they arose, the solitaires of Myadestes disseminated rapidly across the Americas, if genetic data is any indication. The various species of Myadestes diverged from one another perhaps as much as 7 Ma, not very long after the origin of Turdidae itself. The Hawaiian solitaires in particular seem to be closest to the Mesoamerican and Caribbean species, and very possibly are closest to the brown-backed solitaire (M. occidentalis). They dispersed to the Hawaiian islands, apparently by wing, at least 4 Ma. Although no phylogenetic study has been made of these five Hawaiian species together, their broad similarities and the difficulty of transit between Mexico and Hawaii for medium-sized passerines like these probably means that they are one another's closest relatives and arrived as the result of a single dispersal event. Today, three of these species are probably extinct, but all of them persisted into the historical era, leaving behind enough information to draw some conclusions about the whole group.

The first of Hawaii's solitaires to vanish from the islands was a cryptic bird known as the 'āmaui, a shortening of the Hawaiian manu a Māui, "bird of Māui", after a Hawaiian folk hero. In fact, all the thrushes which ranged onto Oahu, Maui, Moloka'i, and Lāna'i (those latter three originally one island, 'Maui Nui', which was partially submerged in recent geological history) were originally known by this same name, but only this bird, M. woahensis, seems to have retained it. Known only from a single holotype, collected by Andrew Bloxam in 1825, as well as some subfossilized bones, what little we know about this species is owed to guesswork based on other solitaires. Abundant in the early 19th Century, it vanished without trace or record by about 1860, thus marking the disappearance of Myadestes from the island of Oahu.

The remaining species have had the fortune to persist for much longer, with two vanishing late in the 20th Century and two more remaining extant to the present day. Each of these shares a common predilection for fruit, feasting occasionally on insects instead during the breeding season, and can be recognized by their calls, which are said to resemble a policeman's whistle. The oloma'o (M. lanaiensis) of Maui, Moloka'i, and Lāna'i, though still officially listed as Critically Endangered, was last definitively spotted in 1980 and is feared to be extinct. A reclusive bird, it was often seen to sit motionless, hunched in the underbrush in between bursts of song.

Illustration of the kāma'o (Myadestes myadestinus) by Frederick William Frohawk from between 1890 and 1899. Retrieved via Wikimedia Commons.

The kāma'o (M. myadestinus) similarly disappeared during the course of the 1980s, last being seen in the Alaka'i Swamp in 1989. The largest of the Hawaiian solitaires at 20 cm (7.8 inches) in length, it was endemic to the island of Kaua'i. It was noted for its habit of suddenly bursting into the air from the underbrush and singing a few notes, and then falling back into cover, a behavior unknown in other solitaires. As early as the 1960s the kāma'o had become very uncommon, retreating into higher altitudes, and was often seen with lesions around its mouth and feet. These are a telltale sign of avian malaria, introduced by mosquitoes breeding in the sties of invasive pigs. This disease must have devastated the kāma'o's population, and has taken its toll on countless other endemic bird species as well. Alaka'i was hit by a succession of hurricanes in the 1980s and 1990s which must have had a terrible effect on the small range of these birds, With no sightings in the last 25 years, even in the face of detailed surveys of Alaka'i and its avian life, it has to be assumed that the kāma'o is extinct.

Puaiohi (Myadestes palmeri). Taken by Eike Wulfmayer at an avian conservation center in Volcano, HI, 2002. Retrieved via Wikimedia Commons.

Another Kaua'i solitaire, however, has happily avoided the kāma'o's fate. The puaiohi (M. palmeri) currently resides in craggy areas above 1,000 meters or so in altitude (3,280 feet) in Alaka'i Wilderness Preserve, in the same area as the kāma'o's last haunts. Unlike its only living relative amongst the Hawaiian solitaires, the 'ōma'o, the puaiohi typically nests in cliff faces. This is a bit odd for a thrush, since most species prefer to nest in branches, cavities, or in a few cases, on the ground. Its particular environmental needs doubtless put additional pressure on this species, which seems to number at most at only 200 individuals in the wild.

'Ōma'o (Myadestes obscurus) as portrayed by Joseph Smit, 1869. Retrieved via Wikimedia Commons.

The 'ōma'o (M. obscurus) of the big island, Hawai'i, seems to be doing somewhat better, with perhaps as many as 200,000 individuals living in the wild on the eastern and southern slopes of Mauna Kea. Efforts to maintain its shrinking habitat on the island are underway in the form of aggressive reduction of the range of feral pigs and other invasive mammals. The puaiohi is under the careful watch of conservationists as well, with captive breeding programs seeing considerable success in reintroducing birds to the wild. The future is brighter for these two birds than for their vanished kin, but introduced mammals which predate upon the solitaires, invasive birds like laughingthrushes which compete with them for food and space, and foreign plants which threaten to reshape what little habitat they have left, continue to endanger the 'ōma'o and puaiohi. In addition, climatic events such as El Niño imperil the species by shortening their breeding seasons with the droughts they often bring to the islands. As we enter another El Niño period in early 2016, it can only be hoped that man-made climate change doesn't doom this unique lineage of thrushes to permanent extinction like the Hawaiian honeyeaters before them.

For another extinct island-endemic bird:

• Red Rail

Sources:

• BirdLife International (2016) Species factsheet: Myadestes lanaiensis. Downloaded from BirdLife on 25/01/2016.
• BirdLife International (2016) Species factsheet: Myadestes myadestinus. Downloaded from BirdLife on 25/01/2016.
• BirdLife International (2016) Species factsheet: Myadestes obscurus. Downloaded from BirdLife on 24/01/2016.
• BirdLife International (2016) Species factsheet: Myadestes palmeri. Downloaded from BirdLife on 25/01/2016.
• BirdLife International (2016) Species factsheet: Myadestes woahensis. Downloaded from BirdLife on 24/01/2016.
• Klicka, John, Gary Voelker, and Garth M. Spellman. "A molecular analysis of the 'true thrushes' (Aves: Turdidae)." Molecular Phylogenetics and Evolution 34. 2005.
• Miller, Matthew J., Eldredge Bermingham, and Robert E. Ricklefs. "Historical biogeography of the New World solitaires (Myadestes spp)." The Auk 124. 2007.
• United States Fish and Wildlife Service: "Draft Revised Recovery Plan For Hawaiian Forest Birds." 2003.

Red Rail (Aphanapteryx bonasia) - A Lost Rail From Mauritius

Above: a plate by Frederick William Frohawk (1861 - 1946), wildlife artist; retrieved via Wikimedia Commons. Below: sketch of a hunted specimen ca. 1601, attributed to one Joris Joostensz Laerle; retrieved via Wikimedia Commons.

Modified from the original posted on the Archosaurophilia Tumblr on January 1, 2016.

The red rail (Aphanapteryx bonasia) was the largest of Mauritius’ rails and certainly the strangest in appearance. Similarly to the dodo and many other birds native to the Mascarene islands, it was completely flightless, and its small wings would have been concealed in life beneath its shaggy, reddish-brown plumage. The only physical remains known from this species are its pelvis and leg bones, which makes it difficult to gauge its full size in life, but contemporary accounts compare it in size to a large hen. Within the rail family, its closest relative seems to be the Rodrigues rail (Erythromachus leguati), also extinct. More distantly, it is allied with the white-throated rail (Dryolimnas cuvieri) of Madagascar, the Seychelles, and Comoros, which today appears to be the only endemic flightless bird remaining on the Indian Ocean’s islands.

Its slender, vaguely ibis-like bill suggests a cursorial foraging lifestyle, preying on small invertebrates. The now-extinct land snail Tropidophora carinata, also endemic to Mauritius, appears to have been one such prey item, as some subfossilized shells belonging to this species carry blunt damage marks consistent with this bird’s beak.

Sadly, very little is known for sure about the red rail, since like many other flightless birds of the world’s oceanic islands, it became extinct a short time after humans colonized its home. The tropical forests of Mauritius began to shrink after the island was claimed by the Dutch East India Company in the 17th Century, spelling doom for this rail, the dodo, and many others, as overhunting and deforestation disrupted their habitat. By 1700, the Red rail had disappeared forever.

Puzzling over this flightless rail and the dodo, centuries before Darwin’s On the Origin of Species, English adventurer Peter Mundy observed:

“Of these 2 sorts off fowl afforementionede, For oughtt wee yett know, Not any to bee Found out of this Iland, which lyeth aboutt 100 leagues From St. Lawrence. A question may bee demaunded how they should bee here and Not elcewhere, beeing soe Farer From other land and can Neither fly or swymme; whither by Mixture off kindes producing straunge and Monstrous formes, or the Nature of the Climate, ayer and earth in alltring the First shapes in long tyme, or how.”

Imperial Woodpecker (Campephilus imperialis) - A Forgotten Giant

Video clip from the Macaulay Library, Cornell Lab of Ornithology.

Modified from the original posted on the Archosaurophilia Tumblr on April 9, 2015.

Although the sad tale of its cousin the Ivory-billed Woodpecker is well-known, the existence of another giant woodpecker which once resided on the same continent, spanning the Sierra Madre ranges of Mexico, is less well remembered. The Imperial Woodpecker (Campephilus imperialis) is, or at least was, the largest woodpecker in the world, a huge and stately bird of the mountains with a prominent crest. Habitat degradation of the forests in which it lived doomed this uncommon species to decline, and ultimately to disappear entirely. The dangerous situation involving cartel violence in the parts of that country which the woodpecker called home have prevented any large-scale investigations into its last haunts, leaving the possibility of its extinction ultimately a mystery.

The footage here was filmed by a Dr. William Rhein in Durango in 1956, and represents the last documented sighting of this species, and the only footage or photographic evidence. It shows a female crawling slowly up the trunk of a pine tree before flying away, never to be seen again.

House Sparrow (Passer domesticus) - The Globetrotter

"Wróbel zwyczajny - Passer domesticus - samiec", a house sparrow in Poland, taken by Alina Zienowicz. Retrieved via Wikimedia Commons.

Modified from the original posted on the Archosaurophilia Tumblr on November 21, 2014.

The house sparrow (Passer domesticus) is a ubiquitous passerid Old World sparrow, native to Eurasia and North Africa, but also found in introduced populations across three other continents, including the Americas, Sub-Saharan Africa, and Australasia. It owes its phenomenal success in part to its ability to adapt to areas of human habitation in wildly varying habitats and climate zones. The house sparrow was among the first species granted a binomial name by Carl Linnaeus, owing to its ubiquity in the European gardens which that scholar so often saw, and it is consequently sometimes treated as the archetypical bird (and perhaps, by extension, the archetypical dinosaur).

House sparrows will feed happily on seeds and grains from plants such as corn or wheat, as well as wild grasses and feed left out by humans. They will also hunt insects on occasion. They can be seen hopping around in gardens, on trees, or on rooftops in inhabited areas, almost never occurring in the wilderness in their introduced range. They commonly congregate in flocks in which males keep a firm hierarchy over the female birds through the winter and fall months, but it is more poorly crystallized in the spring and summer when the females seem to be more assertive. They are naked and helpless upon hatching from a clutch of anywhere between one and eight eggs, and will live for as much as almost sixteen years.

Due to their cosmopolitan distribution and adaptability, the House sparrow is ranked as a Least Concern species by the IUCN, though sub-populations in certain areas, such as the Indian subcontinent, are threatened.

Demoiselle Crane (Anthropoides virgo) - The Little Goliath

"Demoiselle Cranes at Tal Chappar" by Sumeet Moghe, taken on February 1, 2014. Retrieved via Wikimedia Commons.

Modified from the original posted on the Archosaurophilia Tumblr on October 5, 2014.

Demoiselle cranes (Anthropoides virgo) are avian migrants par excellence. The smallest crane in the world, standing at a mere 76 cm (30 inches), the Demoiselle still achieves the most goliath task in the avian world every year. In August and September, tens of thousands of the birds take wing to avoid the icy winters of Central Asia, passing over the Himalayas on their way to the warmer climes of India. The way is arduous, with intense attrition rates from inclement weather and predation by eagles. All the same, they are resilient fliers, capable of traveling hundreds or thousands of miles without needing to land or to eat, and most of the birds surmount this monumental obstacle for years on end.

While some western populations winter in northern Africa instead, it is in India that the demoiselle is best known. In fact, the people of Rajasthan, who call the Demoiselle the koonj, revere the crane for its historic place in Indian literature and mythology. Demoiselles typically mate for life in monogamous pairs, and care for hatchlings for about two months until they fledge. Unlike most cranes, the demoiselle is not a bird of the wetlands, instead preferring upland regions, where it feeds upon a wide array of both plant and animal matter.

Kagu (Rhynochetos jubatus) - New Caledonia's Avian Mystery

Taken at the Walsrode Bird Park, Germany, by Wikimedia Commons user Quartl.

Modified from the original posted on the Archosaurophilia Tumblr on August 7, 2014.

The Kagu (Rhynochetos jubatus) is a curious bird native to the montane forests of the the island of New Caledonia, a French overseas collectivity in the southwest Pacific Ocean. Its placement among the avian family tree has been complicated since the time of its discovery. Once thought to be an ardeid like egrets and herons, it was considered in more recent times to be a gruiform. Of late, it's usually been allied to the sunbittern of Central and South America, suggesting that the two species may be part of an ancient bird lineage distantly related to the tropicbirds (Phaethontiformes).

It's average-sized so far as ground-dwelling birds go, averaging at around 55 cm long. Strictly carnivorous, its diet consists mostly of invertebrates and small reptiles from the forest floor. Its generic name ('rhyno' = nose and 'chetos' = corn) stems from the 'nasal corns', a pair of flaps over the nostrils unique to the Kagu among all birds. It is the heraldic bird of New Caledonia, and despite pressure from introduced mammals which has reduced its range on the island, it is the focus of a number of dedicated conservation efforts which have seen considerable success.