We share the planet with more than ten thousand species of birds. An attempt to see representatives of every species would be a fool’s errand. Some birds live in spots so remote, and in such low numbers, that they haven’t been seen in many years. New species are discovered quite regularly, making “all” a vanishing target. Many enthusiasts turn to the pages of field guides and handbooks, allowing the descriptions and illustrations to fuel their imagination of birds that they are unlikely ever to see.
I did just that this week. I dived into my extensive ornithological library is search of birds that I had not stumbled across before. I skipped over some rather uninspiring birds, including the Brown Tanager and the Drab Seedeater, searching for beautiful creatures with exotic names. Here is what I found.
Painting of a Merida Flowerpecker by Joseph Smit – Proceedings of the Zoological Society of London (vol. 1870, plate XLVI)
The Merida Flowerpecker was discovered in 1871. It can be found in the scrubby highlands of the Mérida region of Venezuela. A teeny songbird, it is sometimes displaced from good foraging spots by hummingbirds. Like hummingbirds, this flowerpecker feeds mainly on nectar and small insects. Both males and females are mostly black or blueish-grey on top, with reddish-brown undersides. The genus name, Diglossa implies that the bird has two tongues or has two voices, while the species name, gloriosa, is the Latin form of the word glorious. Even though we know almost nothing about the breeding biology of this species, the International Union for the Conservation of Nature considers the Merida Flowerpecker to be of least concern.
The scholarly community has known about the Red-collared Widowbird since the late 18th century. This bird has a wide, but patchy distribution across the southern half of Africa, and it is known to occupy a wide range of habitats. Roughly twice the size of a flowerpecker, female Red-collared Widowbirds are nondescript in their colouration. Males could scarcely be more impressive. Some are all black, but most have a bright red slash across their throat. Most impressive is the male’s black tail, which is longer than the rest of the bird in some subspecies. Males with the longest tails attract two or three mates, while more poorly-ornamented males remain unmated. Males and females both contribute to nest building, but incubation and feeding of nestlings are carried out by the females alone. The genus name, Euplectes, refers to their woven nest. The species name, ardens, is Latin for glowing or burning, likely a reference to the males’ bright red collar.
The Snow Mountain Mannikin was unknown to the bird world until 1939, when it was found at an elevation of more than four thousand metres in the Snow Mountains of west-central New Guinea. It is a perfectly respectable little songbird with a black face, light brown bib, darker brown back, striped sides, and a robust grey bill suitable for cracking small seeds. The genus name, Lonchura, refers to the pointed tail feathers of some members of the group. What really stands out about this bird is how little we know about it. The IUCN lists the Snow Mountain Mannikin as having a stable population, but that is something of a guess. We do not know if it resides on its breeding range year-round, or if it wanders widely. The nest is built of grass, but nothing else is known of its breeding biology.
And that is one of the most wonderful things about bird biology. Although we know a great deal about birds, much awaits our investigations.
Photo credits: Painting of a Merida Flowerpecker by Joseph Smit – Proceedings of the Zoological Society of London (vol. 1870, plate XLVI) – https://de.wikipedia.org/wiki/M%C3%A9ridahakenschnabel#/media/File:DiglossaGloriosaSmit.jpg; Birds of Congo stamp collection, including a male Red-collared Widowbird – www.ebay.com; Snow Mountain Mannikin – www.pinterest.com
New Zealand Rockwrens are tough little birds. Living in high-altitude alpine habitat of New Zealand, their nests consist of excavated cavities within vegetated ledges, and cracks on cliff faces and boulders. At forty-four days, their nesting period is surprisingly long for a bird of that size. When confronted by a snowstorm during the breeding season, a parent may tunnel down through the snow to reach its chicks. Despite being warriors, could it be that New Zealand Rockwrens are helpless in the face of invasive mammalian predators?
If a plant or animals has been moved by humans from its native lands, across a natural barrier, and has managed to establish a self-sustaining population in that new spot, then it is considered to be “introduced.” If that species goes on to have negative consequences for the wildlife or landscape of its new home, or on human health or the economy, then the creature is considered to be “invasive.” A number of invasive mammals are causing trouble in New Zealand. These include stoats, house mice, rats and possums. Numbers of the New Zealand Rockwren have declined to the point where they are considered endangered. Are invasive, predatory mammals to blame?
Conservation biology Kerry Weston of New Zealand’s Department of Conservation and her colleagues studied the breeding biology of the New Zealand Rockwren, with particular emphasis on the potential impact of invasive mammals. At three high-altitude sites, Weston et al. searched for rockwren nests, and followed their progress. In some cases, nests were monitored using continuous video-recording and motion-activated cameras. Mammals were trapped and disposed of in some locales.
Weston and her crew located 146 rockwren nests, and reported on some interesting aspects of the birds’ breeding biology. For instance, both parents contributed to incubating the eggs and providing for the nestlings during the day, but females alone incubated eggs and brooded young at night. As the nestling grew in size, they received food every three or four minutes during daylight hours. Nestlings are noisy, and can sometimes be seen begging from the nest’s entrance.
The most common cause of rockwren reproductive failure was predation by stoats, rats and mice. Cameras revealed that stoats ate eggs, nestlings and brooding adults. However, in spots where predators were controlled, no predation by stoats was confirmed, and the leading cause of failure was nest abandonment, sometimes the result of extreme weather.
In their five-year study, just thirty-three stoats, ten rats and one mouse were captured. Despite the low number of mammalian predators in the landscape, it was clear that these animals had considerable negative consequences for populations of the endangered rockwren. The impact of invasive predators on insular and lowland bird populations is well established. Less well known is the effect of invasive mammals on birds breeding at high altitudes. Weston et al. wrote: “Novel predator control techniques that can be safely applied at scale above treeline are urgently required.” Let’s hope that such control will be forthcoming, and that the New Zealand Rockwren’s endanagered status will soon be changed.
Weston, K. A., C. F. J. O’Donnell, P. van Dam-Bates and J. M. Monks. 2018. Control of invasive predators improves breeding success of an endangered alpine passerine. Ibis 160:892-899.
Photo credits: New Zealand Rockwren stamp – www.pinterest.com; photograph of New Zealand Rockwren courtesy of Pete McGregor - http://stmedia.co.nz/wgl-nzac/2011/02/have-you-seen-the-alpine-rock-wren/
It is hard to imagine that the field of astronomy would have made much headway if telescopes had never been invented, or that cell biology would have advanced far without microscopes. Even though the most powerful tool in any scientific endeavor is a curious mind, the application of technology helps too.
Those techniques do not always have to be sophisticated or expensive. In a marvelous example of understatement, Sanjo Rose and Dieter Oschadleus of the University of Cape Town in South Africa recently wrote: “Bird ringing provides novel insights into the private lives of birds.” Let me be a little less restrained; without the application of numbered bands to the legs of millions of wild birds, much of the lives of birds would still be a mystery to us.
Bird ringing, known is some parts of the world as bird banding, and the subsequent recapture of some of those banded individuals, allows us to learn about where, when and how they live their lives. Ringed on its breeding territory, a bird might be recaptured on its wintering grounds, providing us with a link between the two regions. If a combination of coloured legs bands are used for individual identification, we can sometimes follow a bird as it interacts with its environment and other birds around it.
It is almost certain that some readers of this column will be engaged in bird ringing as a hobby. I have met hobbyists that have ringed tens of thousands of birds. I have ringed a far smaller number of birds for research purposes. All of this activity contributes to a better understanding of the avian world. In southern Africa, the activities of bird ringers is coordinated by the South African Bird Ringing scheme. Since 1948, more than 2.3 million birds have had numbered rings applied to their legs.
In a recent publication, Rose and Oschadleus reported on their efforts to learn about the longevity of estrildids, or waxbill finches, based on the banding and recovery of birds in southern Africa. Old World birds, estrildids can be found over large parts of Africa, southern Asia and Australasia. Within the group’s 130 species, some will be very familiar to fanciers of cage birds. These include the Australian Zebra Finch, Java Sparrow and Gouldian Finch. Rose and Oschadeleus found that more than 150,000 estrildids have been banded in southern Africa. Five species were represented by more than 10,000 ringing records each, including the Blue Waxbill and the Red-headed Finch. Many of those ringed birds have been recovered. Other species, including the Cinderella Waxbill and the Locust Finch have been ringed fewer than one hundred times, and none have been seen subsequently.
Longevity is a crucial demographic if we are to understand the population dynamics of species, and so Rose and Oschadleus reported those figures for southern African birds with the largest datasets. They found, for instance, that 27,813 Red-headed Finches had been marked, and that the oldest individual had been at least 5.2 years of age. More than twenty-thousand Bronze Manakins had received rings, but the oldest had been only 3.7 years of age. The record holder was a Blue Waxbill, one of 28,037 ringed. It had first been banded on June 25, 1996 and recovered on February 21, 2009. By my calculations, this bird’s minimum age was twelve years, seven months and twenty-eight days.
If you are involved in bird ringing, well done! You are contributing to a better understanding of birds. If you are looking for a new hobby, perhaps you will consider contacting the wild bird enthusiasts’ group in your area to find out how you could become part of the program.
Rose, S. and H. D. Oschadleus. 2018. Longevity summary from 69 years of Estrildidae ringing data in southern Africa. African Zoology 53:41-46.
Smooth-billed Anis are the late-1960s, commune-dwelling hippies of the bird world. Found as far north as the southern United States, and residing over much of the Caribbean and Central and South America, as many as six females lay their eggs in a shared nest. Ani chicks are raised by the group, with the help of multiple males and non-breeding helpers. It all sounds like a synergistic, happy-go-lucky love fest.
Closer examination shows that the situation isn’t quite so lovely as it appears. Communal they may be, but members of a Smooth-billed Ani group sometimes bury eggs, or roll eggs up the side of the nest and toss them out. There are at least two functions for this ovicidal behaviour. By destroying the eggs of others, a female can reduce the competition for limited resources for her own chicks. If she buries older eggs, or tosses older eggs from the nest, she helps to ensure that her chicks will not be the youngest in the nest. In doing so, her chicks will not be at a disadvantage because of competition with older chicks.
Leanne Grieves and James Quinn of McMaster University in Canada studied the ovicidal behaviour of Smooth-billed Anis in Puerto Rico. They explained that when they are first laid, ani eggs are white because they are covered with a thin chalky layer. When that layer wears away over a period of days, the underlying blue colour of the shell is exposed. Grieves and Quinn asked whether female anis might use the blue colouration of shells to indicate that the eggs had been laid some days earlier, and use that cue to eject or bury eggs when laying their own.
The researchers scraped some eggs with a small brush to wipe away the chalky covering, leaving them blue. In order to introduce a level of control, other eggs were handled, but the chalky covering was not removed, and so the eggs remained white.
Grieves and Quinn found that blue eggs were no more likely to be buried that white eggs. Blue eggs were also no more likely to be thrown from the nest. Colour does not seem to be a cue. However, they found that females in larger communal groups were more likely to engage in both of the destructive behaviours than females in smaller groups. In larger groups with four or five females, an egg was twice as likely to be destroyed as an egg in a group with just two or three females.
Given their size, female Smooth-billed Anis lay very large eggs; nearly 18% of their body weight goes into each one. An egg is a large investment. The greater the group size, the greater the competition. In order to make her investment of energy and resources worthwhile, it seems that females in larger groups will go to great lengths to ensure that her eggs, and therefore her chicks, are the ones to survive.
Life can be tough, even in a commune.
Grieves, L. A., and J. S. Quinn. 2018. Group size, but not manipulated whole-clutch egg color, contributes to ovicide in joint-nesting Smooth-billed Anis. Wilson Journal of Ornithology 130:479-484.
Photo credits: Smooth-billed Ani – www.pinterest.com; Smooth-billed Ani stamp - http://www.birdtheme.org/showimages/antiguab/i/anb200010l.jpg.
Specialists in the field of biological conservation need to be simultaneously conservative and creative in their practices. When it comes to endangered creatures, we can rarely afford to be cavalier in using new, unproven methodologies. Even so, a technique that serve the needs of one threatened species may be entirely inappropriate for a different species. How can we be cautious and innovative at the same time?
It will be desirable to release animals to the wild after a period in captivity in several circumstances. For instance, individuals born in captivity, but released to the wild, may represent salvation for some species. Animals that have been confiscated by authorities may be used to bolster a declining wild population. It may be deemed useful to translocate individuals from a healthy wild population to an area from which the species has been eliminated.
Consider the Spix’s Macaw, native to northeastern Brazil. According to the IUCN, this Macaw is critically-endangered, and possibly extinct in the wild. With luck, the few individuals held in captivity will allow us to reestablish wild populations in the future. However, we don’t currently know the best way to ensure this. How do we obtain answers without risking the few individuals that are left?
Alice Lopes of the Instituto de Pesquisa e Conservaçăo in Brazil and her colleagues studied Blue-fronted Amazons that had been released to the wild after a period in captivity. The IUCN lists this parrot as of least concern. Lessons learned from releases of this reasonably common parrot might be applied to other, more-threatened species. The goals of Lopes and her colleagues was to “evaluate techniques of management and monitoring employed in the translocation of a group of captive-raised Blue-fronted Amazons.”
Thirty-one Blue-fronted Amazons were obtained from the Wild Animal Triage Centres (CETAS) in Brazil. Each had been in captivity for at least three years. These birds were studied at a site at a private farm in southeastern Brazil. Before release, the birds were trained to recognize predators. They were held in large aviaries that allowed them to practice the skills they would need to survive in the wild. After ten months of training, the parrots were permitted to leave, although they were permitted to return to the aviaries, and were provided with food to supplement what they found in the wild.
The thirty-one parrots released had a range of fates. Three were known to have perished. The whereabouts of five others could not be determined. Ten others showed behaviours that suggested they were adapting to life in the wild. The remaining thirteen individuals continued to behave in a way that better suited captive life, such as remaining near the aviary, and interacting with humans. It appeared that some members of the final group were captured by people in the area.
The study of Lopes et al. showed that “confiscated ex-pet Blue-fronted Amazon Parrots can be good candidates for translocation, but a training program should be applied to them prior to their release.” For instance, subjects need to learn to stay away from humans in order to avoid being recaptured.
Wild populations of the Blue-fronted Amazon range from Bolivia to northern Argentina. Even though it is considered to be of least concern, its numbers in the wild are in decline. According to the IUCN, between 1981 and 2005, 413,000 wild-caught individuals are known to have been sold internationally. Between 2008 and 2010, the CETAS of Brazil received 3,395 individual Blue-fronted Amazons, of which 2145 were seized. A quick search of YouTube will reveal why the Blue-fronted Amazon is so popular as a cage bird. It is to be hoped that will remain sufficiently common in the wild so as to continue to serve as a model for studies of conservation practices.
Lopes, A. R. S., et al. 2018. Translocation and post-release monitoring of captive-raised Blue-fronted Amazons Amazona aestiva. Acta Ornithologica 53:37-46.
The Wilson Journal of Ornithology is a highly respected repository of information related to bird science. The most recent issue of the journal includes sixteen long articles and twelve briefer communiques. Readers of that issue can learn about research on the effects of flooding of the Missouri River on Least Tern reproduction, the nesting behaviour of Gray Tinamous in Ecuador, and parental behaviour of Costa Rican Clay-coloured Thrushes.
The journal began one-hundred and thirty years ago under the name The Ornithologists’ and Oologists’ Semi-annual. That title lasted only a year, being replaced by the more ponderous Semi-annual, Agassiz Association, Department of the Wilson Chapter. The name was changed to The Wilson Quarterly in 1892, and then The Journal of the Wilson Ornithological Chapter of the Agassiz Association in 1893. Things settled down after that, and the journal was called The Wilson Bulletin from 1894 to 2005.
In the early years, most subscribers to the journal were dedicated laypeople, rather than professional ornithologists. Articles from more than a century ago reflected the naive state of the field at the time. An account of birds seen while on a cruise might have been followed by an description of the timing of nesting of birds in a local cemetery. Even so those old issues can for interesting reading.
The second issue of the fifth volume of the journal was just eight pages long. On the second page of that issue was a statement short on details but rich in inuendo. It read: “Charges of sufficient seriousness have been preferred against Messrs. J. W. P. Smithwick and F. T. Pember to warrant their expulsion from the Chapter. A majority of the Executive Council have voted to remove their names from our roll. Their crime is fraudulent methods in Oology.”
It seems that J. W. P. Smithwick of San Souci, NC, and F. T. Pember of Granville, NY, had been active members of the group to that point, including writing articles with titles like: “Collecting in the Gila Valley” and “The Burrowing Owl: Speotyto cunicularia hypogaea.” Despite being on the membership list in Volume 5, issue 1, their names were missing from that list in issue 2.
I have not discovered what crimes against oology had Smithwick and Pember dismissed from the society, but I have found a few additional details about their comings and goings. Franklin Tanner Pember was born in 1841 and died in 1924. A businessman with interests in oil and oranges, his boyhood fascination with nature led to a substantial collection of artifacts, including bird nests and eggs. He and his wife, Ellen Wood Pember, established the Pember Library and Museum in 1909. That facility still serves the people of eastern New York state.
An online article by David Cecelski suggests that John Washington Pearce Smithwick was born in North Carolina in 1870, and was an avid collector of bird eggs by 1888. Shortly after being drummed out of the Wilson Society, Smithwick donated his collection of eggs to the state’s natural history museum. He then became a physician. I have not seen Cecelski’s reference material, and so cannot comment on his assertion that Smithwick was a hate-mongering racist.
Birds are angelic. Birds biologists will be judged by time.
Photo credits: reprint of The Ornithologists’ and Oologists’ Semi-annual Volume 1 (1889) – www.empik.com; image from page 61 of “The Ornithologists’ and oologists’ semi-annual” (1889) - https://www.flickr.com/photos/internetarchivebookimages/14750528982/
Birds that migrate to far-northern latitudes for breeding may arrive to find a wealth of opportunity. Grazing geese are likely to find endless fields of fresh grass. Insect-eating pipits and wagtails may find their protein-rich quarry to be a non-depletable resource.
Bird biologists have found that the first individuals to return from their wintering areas to their northern breeding grounds generally have greater reproductive success. The causes of this success are many. The first birds back may have the greatest opportunity to recover from the challenges of migration, and could find access to the best breeding territories. If the first breeding attempt fails, early breeders have a greater opportunity to try again. Perhaps earlier males can increase their reproductive success by mating with females who are not their social mate. By breeding earlier, their chicks may have a longer period to grow and acquire the reserves necessary for successful southward migration.
It is possible, of course, that some birds will migrate northward too early, and will arrive to find their breeding grounds in the grip late-Winter weather. Even so, on the whole, earlier seems to be better.
However, as with so many aspects of bird biology, this phenomenon has been reasonably-well studied in species living in temperate zones, with far less information available for tropical species. Vanessa Bejarano and Alex Jahn of the Universidade Estadual Paulista in São Paulo, Brazil, sought to address that gap in our knowledge.
Between 2013 and 2016, Bejarano and Jahn studied a population of Fork-tailed Flycatchers in the Estação Ecologica de Itirapina in southern Brazil. Described as intra-tropical migrants, these flycatchers come to their breeding grounds from their off-season homes in northern South America. The birds were colour-banded for individual identification. The researchers monitored flycatchers on the study site, noting when they first arrived, and followed their breeding activities.
Life in the tropics can be challenging for birds, and Bejarano and Jahn found that only ten percent of nesting attempts were successful. On average, male flycatchers were seen on the breeding grounds earlier than females, a phenomenon known as protandry. Males that arrived first attracted females that laid eggs earlier. Nest success was higher when egg laying was earlier. In summary – earlier is better. Although this relationship between dates of arrival on the breeding ground and breeding success has been established for a number of birds in temperate regions, this seems to be the first study to show the association for birds that live within the tropics.
Further study will be needed to determine how male Fork-tailed Flycatchers manage to arrive to breed before females do, and why earlier arrival translates into greater success. The authors suggested that: “further research on the subject would benefit from a multi-disciplinary, comparative approach among migratory systems.” In an era of global climate change, the results of such research is likely to prove valuable.
Bejarano, V., and A. E. Jahn. 2018. Relationship between arrival timing and breeding success of intra-tropical migratory Fork-tailed Flycatchers (Tyrannus savana). Journal of Field Ornithology 89:109-116.
Photo credits: Brasilian stamp – www.pinterest.com; painting of a Fork-tailed Flycatcher by John James Audubon – www.amazon.com
As recently as 2009, the IUCN considered Africa’s Hooded Vulture sufficiently abundant as to be of “least concern.” Its status was downgraded to “endangered” in 2011, and dropped again in 2015 to “critically endangered,” and that is where this vulture sits today. It isn’t that Hooded Vultures are particularly hard to find; there are thought to be as many as 197,000 of them. All told, they have a comparatively large range in Africa, including many countries from Angola to Zimbabwe. Instead, the Hooded Vulture is considered to be critically endangered because of an extremely rapid decline in its abundance. According to the IUCN, this decline is the result of “indiscriminate poisoning, trade for traditional medicine, hunting, persecution and electrocution, as well as habitat loss and degradation.”
The bird might be rare elsewhere, but in recent years it seemed to be doing quite well in Ghana, where it was seen commonly in landfill sites, food markets, urban dumpsters and around slaughterhouses. In Ghana’s capital city, Accra, flocks of five hundred vultures might be seen. Then, at least according to anecdotal evidence, Hooded Vultures started rapidly decreasing in number.
Francis Gbogbo of the University of Ghana, Japheth Roberts of the Ghana Wildlife Society, and Vincent Awotwe-Pratt of the Conservation Alliance saw the need for a critical examination of the Hooded Vulture’s abundance in its urban stronghold in Ghana, and an investigation of its principle sources of mortality.
The study was conducted in Accra. From just 377,000 residents in 1960, the human population of the city has grown to as many as 4,000,000 in the greater metropolitan area. Weekly counts of Hooded Vultures were made on the Legon Campus of the University of Ghana. As many as 220 vultures were seen between November 2010 and January 2011, but this number plummeted to just five individuals in 2015 and 2016. The numbers seemed to represent an actual decline, and not just a relocation. Some of the decline in vulture numbers may have been a result of competition with Pied Crows which increase in number on the university campus over the same period. The introduction of covered waste bins on campus may also have decreased the opportunity for scavenging by vultures.
Similarly, in an attempt to decrease the risk of collisions between airplanes and vultures, efforts were made to decrease the attractiveness of the region around Kotoka International Airport. For instance, refuse dumps in the area were closed or covered. The recent closure of unhygienic slaughterhouses in Accra likely also had an affect on Hooded Vulture numbers.
The researchers examined the published literature for details of the vulture’s abundance. Gbogbo et al. also spoke with vulture researchers, as well as those who had experience with the habitats frequented by Hooded Vultures, including waste managers, scrap dealers and refuse scavengers. It seems that the capture and sale of Hooded Vulture carcasses for use in traditional medicines and black magic is not insubstantial. The researchers found that the value of the head of a vulture in a market in Tamale was 200 Ghana cedis. That is about two-months’ wages for a middle-income earner in Ghana. Many dead vultures and vulture parts are apparently exported to Nigeria. Some vultures are being captured and sold as food, sometimes to an unsuspecting public.
Nothing about conservation of the Hooded Vulture is likely to be simple in Ghana. Clearly it is not appropriate to reopen refuse dumps in order to provide foraging opportunities. Gbogbo and his coworkers identified “the need for an intensive education of the Ghanaian populace on the significant status and need for the protection of the species.”
Gbogbo, F., J. S. T. Roberts and V. Awotwe-Pratt. 2016. Some important observations on the populations of Hooded Vultures Necrosyrtes monachus in urban Ghana.
Wild birds are better understood that any other group of animals. Consequently, the development of many general concepts in taxonomy, ecology, anatomy, physiology and evolution has been based on our accumulated knowledge of birds. Fortunately, there are many mysteries yet to be solved, even in the best-studied species of birds. The discipline of ornithology has many generations of study ahead.
Remarkably, some bird species are so enigmatic as to be represented by only one stuffed specimen each. This group includes the Spotted Green Pigeon (Caloenas maculata), the Mysterious Starling (Aplonis mavornata), the Makira Woodhen (Pareudiastes silvestris), Vaurie’s Nightjar (Caprimulgus centralasicus), the Cayenne Nightjar (Setopagis maculosa), and the Black-browed Babbler (Malacocincla perspicillata). We have even less material to examine in the case of the Nechisar Nightjar (Caprimulgus solala), known from only a single preserved wing, and the Double-banded Argus (Argusianus bipunctatus), a pheasant from which we have only a single feather. Not surprisingly, some of these birds are considered to be critically-endangered or even extinct, but the IUCN considers others to be “data deficient,” awaiting further study.
Might an expedition designed to find and study one or other of these birds be a fool’s errand? Are we certain that these birds even exist as proper species, or could the stuffed specimens represent single peculiar representatives of other reasonably common species? Alexander Kirschel, Emmanuel Nwankwo and Juan Carlos Gonzalez of the University of Cypress and the University of Oxford set out to answer those questions for the White-chested Tinkerbird, Pogoniulus makawai.
In 1964, Jali Makawa and Michael Irwin were collecting bird specimens in the forests of northwestern Zambia. On September 6 of that year, Makawa and Irwin collected a bird that was similar to Yellow-rumped Tinkerbirds (P. bilineatus), common and widespread, but with sufficient differences in plumage for it to be described as a unique species. That single stuffed specimen of the White-chested Tinkerbird resides in a drawer at the Natural History Museum in Tring, UK, with the catalogue number NHM 1964.33.1
But where are its buddies? Why have repeated surveys of the area not reported the White-chested Tinkerbird? As Kirschel et al. asked: “is this a valid taxon and does it still endure an extremely rare and localized existence?” Alternatively, could NHM 1964.33.1 be nothing more than an odd presentation of something else?
Kirschel and his colleagues collected a small sample of tissue from the foot of the single White-chested Tinkerbird specimen. Genetic material was extracted from the sample, and amplified using well-established laboratory procedures. The resulting DNA sequences were then compared to those of other types of tinkerbirds found in the same part of Africa.
The results of the study were not ambiguous. The specimen previously thought of as the White-chested Tinkerbird is just a peculiar presentation of the Yellow-rumped Tinkerbird. The latter species has several subspecies; the work of Kirschel et al. was able to place the White-chested Tinkerbird specimen within a small group of subspecies known as the leucolaimus complex. Results rarely get much more specific than that. Peculiarities of the plumage of the single White-chested Tinkerbird specimen might be the result of a mutation, or a response to some aspect of its environment. However it is unlikely that precious time and resources need to be spent to conserve this tinkerbird in the wild.
Kirschel, A. N. G., E. C. Nwankwo and J. C. T. Gonzalez. 2018. Investigation of the status of the enigmatic White-chested Tinkerbird Pogoniulus makawai using molecular analysis of the type specimen. Ibis 160:673-680.
In the previous installment of A Traveller’s Guide to Feathers, I described recent research on the natural history of the Okinawa Rail. Dr. Shun Kobayashi and his colleagues discovered, among other things, that this endangered rail is omnivorous, exploiting a wide range of plant and animal foods, and that they forage in more than one habitat.
Wanting to know more about the Okinawa Rail and other threatened wildlife in the area, I contacted Shun Kobayashi, a post-doctoral researcher at the University of the Ryukyus. He responded immediately with great energy and enthusiasm. He pointed out that the Okinawa Rail has become a symbol of Okinawan animal life. Consequently many people in the region are aware of the bird, but many of those are unaware of its plight. Predation by introduced mongooses and cats is likely the most serious source of rail mortality, but habitat loss and collisions with automobiles also contribute. The population fell through 2007, before beginning to recover.
Shun Kobayashi told me that the Ministry of the Environment became involved, creating a breeding program, and attempting to remove mongooses from northern parts of the island where their impact on native wildlife is greatest. Consequently, rails are becoming more numerous, although some threats remain.
Under the guidance of Professor Masako Izawa, university students continue to consider the natural history of Okinawa Rails. One student tracks individuals in the wild, and another studies captive individuals. The professor’s website describes other work that her group is engaged in. “We conduct research on mammal home ranges, environmental utilization, social structure, breeding behavior, feeding habits… Animals that students have researched… include the Iriomote wild cat, the Tsushina leopard cat, the flying-fox, Cervus nippon keramae, different types of mice, the blue rock thrush, and more.” The University of the Ryukyus has a very navigable website: http://www.u-ryukyu.ac.jp/en/.
Shun Kobayashi pointed out that Dr. Kiyoaki Ozaki, a researcher at the Yamashina Institute for Ornithology, has been studying Okinawa Rails for more than thirty years. You can learn more about the Yamashina Institute at: http://www.yamashina.or.jp/hp/english/index.html.
Shun Kobayashi explained that his interests were not just for our avian friends, but also for plant pollination systems that depend on mammals, and the ecology of animals that are found only in the Ryukyu Islands. He is, for instance, currently studying the impact of dogs and cats on the native animals of Okinawa-jima Island. I was told that the support of non-governmental organizations, such as the Conservation and Animal Welfare Trust, Okinawa, are key elements in the study of wildlife in the area. “I could not do the research without their support,” wrote Shun.
Despair only occurs when no hope remains. I see no need for despair for our natural world as long as people such as Dr. Shun Kobayashi, Professor Masako Izawa, and Dr. Kiyoaki Ozaki believe that there is a future.
Photo credits: Okinawa Rail safely crossing a road – www.pinterest.com; world map showing the location of Okinawa Rails – Yamashina Institute of Ornithology (http://www.yamashina.or.jp/hp/english/okinawarail/about_or.html)