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Home , Aepyornis, Elephant bird, Ostrich, Southern fiscal, Stephanoaetus

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offered for (illegal) sale as curios. A little- The Arabian Nights. The rokh, so the story known fact about the is that until as goes, was an eagle-like so enormous recently as the mid-19th century they were that it preyed on elephants. There is good used by humans to transport liquids. There reason to suspect that this fanciful tale enormous, is something distinctly surreal about the originated from that occurred on notion of a gigantic , several centuries , and elephant birds have long old, being used as a water container by a been seen as the obvious candidates. thirsty Malagasy traveller. But Steven Goodman and William enigmatic & extinct All the elephant birds were extinct by the Jungers have recently pointed out that The elephant birds of Madagascar 17th century. A French governor stationed another extinct Malagasy bird could in Madagascar during the mid-1600s men- have contributed to the origin of this n the mid-1800s three huge eggs and three , mainly in forests, since the spiny vegeta- tioned -like birds that occurred in legend. Belonging to the same and were transported from Madagas- although the actual numbers remain un- tion typical of Madagascar’s arid regions remote regions, but he did not see them Wikimedia Commons (2) approxi­mately the same size as ’s car to France, and the Western clear. This uncertainty reflects the fact generally is characterised by other, iso- at first hand. There is no way of knowing Aepyornis skull on display in the National , mahery worldI came to learn that this island had that all these species were described topically distinct, photosynthetic path- whether the birds still existed at that time Museum of Natural History, Paris. was probably a specialised hunter. once been home to giant birds. Named from the morphological traits of bones ways. It has been proposed by several or if his accounts were based on already Perhaps sailors’ tales of a large and for- Aepyornis maximus by French natural- and eggshell remains. Until molecular researchers that elephant birds were im- vanished creatures that persisted only in Another possible cause concerns natu- midable forest eagle became intertwined ist Etienne Geoffroy Saint-Hilaire, the techniques are used to analyse extracted portant seed dispersers for a number of the oral traditions of local people. ral climate change. There is evidence that with accounts of the gigantic elephant species that laid the eggs was the larg- DNA, it will be almost impossible to rule Malagasy trees, including the six species The reasons for the elephant birds’ southern Madagascar, which appears to birds and the chimera that emerged was est bird known to have existed in recent out scenarios such as two ‘species’ in re- of baobabs endemic to the island. demise are far from clear. Human pres- have been one of the strongholds of the the terrifying raptor of Arabian legend. millennia, standing three to four metres ality being the males and females of one ence in Madagascar dates back at least elephant birds, has become substantially ANDREW McKECHNIE in height and weighing about 450 kilo- sexually dimorphic species, as happened The eggs of A. maximus 2 000 years, and possibly to a significantly drier within the past thousand years. grams, more than the combined weight in the case of ’s . were truly enormous, earlier date. Elephant birds and humans Many associated with moist References of four . Madagascar in the age of the elephant each with a volume thus co-existed for at least the better part of habitats are known from sub- sites Clarke, S.J. et al. 2006. ‘The amino acid and Other species of elephant birds have birds was a very different place to Mada- two millennia and no unequivocal archae- in the area but no longer occur there. It stable isotope biogeochemistry of elephant subsequently been described. Current gascar today. The island’s forests were equivalent to about ological evidence for human predation of may well be that habitat changes driven bird (Aepyornis) eggshells from southern thinking is that there were probably four home to an incredible variety of extinct seven ostrich eggs the birds has been found. This suggests by this shift in climate contributed to the Madagascar.’ Quaternary Science Reviews, mammals, among them gorilla-sized le- that the overkill hypothesis, so often in- of the birds. 25: 2343‒2356. murs and aye-ayes four times larger than The Clarke et al. paper also presented voked to explain megafaunal Elephant birds have been Goodman, S.M. and Jungers, W.L. 2014. the single extant species. Sloth- information about oxygen isotopes and that coincided with the arrival of humans, mooted as the origin of the Extinct Madagascar: picturing the island’s moved along the undersides of branches the data that emerged are relevant to probably does not explain the disappear- legend of the rokh, the giant past. University of Press, Chicago in a manner akin to their South Amer­ reconstructing the elephant birds’ ecol- ance of Madagascar’s giant . bird in Sindbad’s adventures in and London. ican namesakes. Dwarf hippopotami ogy. The stable oxygen isotope signatures wallowed in lakes and rivers, and bizarre of eggshells reveal that elephant birds creatures known as bibymalagasias, or drank regularly from groundwater-fed Madagascar aardvarks, fed on ants and ponds, wetlands and lakes in coastal are- termites. as of southern Madagascar and were thus Almost nothing is known about the probably associated with habitats in the natural history of elephant birds, but sev- vicinity of such water sources. eral inferences can be drawn from bio- One aspect of ecology chemical analyses of their remains. The that can be inferred without resorting to most significant recent study appeared biochemical analysis is that some species in 2006, when Simon Clarke and his col- nested colonially. At the southern tip of leagues reported that the stable carbon Madagascar, coastal dune sites with ex- isotope signatures of Aepyornis eggshells ceptionally high densities of A. maximus from southern Madagascar are consistent eggshell fragments reveal that these gi- Aepyornis maximus with the birds feeding on plants with C3 ants nested in large colonies, with breed- photosynthesis. This reveals that elephant ing sites possibly being used by many birds fed mainly on trees and shrubs, and generations. To this day, intact eggs are grasses and succulent plants represented occasionally found in this area. only a small part of their diet. The eggs of A. maximus were truly enor- The C3-dominated diet further sug- mous, each with a volume equivalent to gests that the elephant birds foraged about seven ostrich eggs. Many visitors to modern-day Madagascar will have en- Wikipedia/ Size comparison between the giant egg of the countered these eggs, which have been Homo sapiens Struthio camelus Houston Museum of Natural Science elephant bird and that of the Common Ostrich. pieced together from fragments and are

10 african birdlife january/february 2016 news & views 11 news & views

2nd W more than just 2nd World Confer World Seabird Conference ence : Global Ocean Sentinels October 26 – 30, 2015 C making waves ape Town, hot air nterested in how seabirds navigate at For me, one of the highlights was the Scientists have long known that birds are feeling the heat due to sea, how young seabirds learn their suite of findings from the Oxford Navi- climate change. However, a new study of a dozen affected species in trade or how an increasingly stormy gation Group. They used a clock-shift the Western Cape suggests their decline is more complex than previ- planetI is going to affect seabirds? These experiment to show that breeding Manx Hosted by African World Seabird Union Seabird ously thought – and in some cases more serious. were just some of the topics explored at Shearwaters use a sun compass to orien- Group the Second World Seabird Conference tate at sea, but also follow visual landmarks ccording to the study, published comparison of data contained in the two (WSC), which took place in Cape Town once they are in sight of land. Previous in Conservation Physiology and Bird Atlas (SABAP) sur- in October 2015 under the auspices of work on shearwaters has confirmed the their parents and many do not survive carried out by scientists from the veys conducted 15 years apart. This data the World Seabird Union. importance of scent for homing. the first few months, when they seldom PercyA FitzPatrick Institute (University was matched with climate data for the The WSC brand was established in 2010, Many studies used the latest tracking dive to more than 100 metres. Those of Cape Town) and the Nelson Mandela comparative period, as well as with physio­ when the Pacific Seabird Group hosted technology, but have moved beyond sim- that make it through this period show Metropolitan University in Port Elizabeth, logical data. A key aspect of the study is a the first meeting in Canada. It also saw ply documenting migration routes and an increase in dive depth and duration, there could be several reasons why birds comparison of climate and bird population 21 regional seabird organisations joining are now attempting to understand how reaching depths of 250 metres (but still are being negatively affected by human- data with the heat response – or ‘thermal forces to form the World Seabird Union individuals behave. The general pattern less than adults). By comparison, adult made climate change. tolerance’ – of each bird species. In this to promote seabird research, management emerging for most species is that individu- Greater Frigatebirds return to their col- They suggest that, contrary to expecta- way researchers assessed to what extent dionne miles and conservation worldwide. als tend to use the same parts of the ocean ony each night for five to seven months tions, the birds’ heat tolerance – or lack birds can cope with changing temperature The study revealed that the fynbos-endemic Following the success of the first WSC, consistently whether they are breeding, to feed their fledglings, giving the young- thereof – is not necessarily the main fac- and whether this is the primary indicator Orange-breasted Sunbird showed a 10 per the African Seabird Group offered to host migrating or wintering, but there can be sters plenty of time to learn the aerial tor causing declines. Other factors, such of alterations in bird abundance. cent decrease in reporting rate in the 15 years the second WSC. The meeting attracted variation linked to age and sex. skills they will need to survive their first as changing fire and rainfall cycles and To obtain data, researchers subjected between the SABAP1 and SABAP2 surveys. 562 delegates from 52 countries, includ- Even birds as small as storm petrels year, which is spent almost entirely aloft. altered bird behaviour patterns, could also birds to a range of temperature tests to ing 173 students. Local students were well can now be tracked. Most Leach’s Storm The conference also tackled many ap- be responsible­ for the decline according determine their physiological response. conservation intervention. ‘Conservation represented and three from the University Petrels from Nova Scotia winter off West plied subjects, ranging from managing to the study, which includes some well- Considerable variation in the relation- action appears to be urgently needed for of Cape Town featured in the top 10 stu- Africa, but some reach the Cape. And conflicts with fisheries and introduced known species such as the Malachite Sun- ship between the response to temperature the Cape Rockjumper and Protea Seedeat- dent presentations. most Sabine’s Gulls breeding west of Baf- predators to the influences of offshore bird and the Familiar Chat. and rate of species’ decline prevented re- er if their declines are to be properly un- The conference was titled ‘Seabirds: fin Island in the high Canadian Arctic wind farms and plastic pollution. One Co-lead researcher Susie Cunningham searchers confirming a direct link across derstood and halted,’ the study says. ‘We Global Ocean Sentinels’, but it covered winter off Peru, although a few migrate worrying theme was how increasing says a better understanding of how climate the board between how species are faring need further research to determine the virtually all aspects of seabird biology to southern Africa; members of one pair storm frequency and severity, linked to change affects bird species could help de- under current climate change and their cause of decline of Protea Seedeaters and and conservation. In addition to show- even consistently visit different oceans. global climate change, is likely to affect velop conservation strategies to increase thermal physiology. to assess how Cape Rockjumpers may best casing the latest seabird research, it pro- Studies are increasingly addressing seabirds. chances of survival. ‘We know climate Despite this, the study showed a strong be assisted to cope in the face of continu- moted legacy projects such as the global how young seabirds learn to survive af- With so much on offer, it’s a pity that change is linked to changes in species’ correlation between temperatures within ing climate change.’ seabird colony and tracking databases ter leaving their breeding islands. Young more South African birders didn’t take numbers and distributions, but we don’t birds’ ranges and rates of decline, with Cunningham says the overall findings that were launched at the first WSC. The are left to literally sink or the opportunity to attend the meeting. always know exactly how or why,’ Cun- cool-climate species faring worse under suggest scientists should not jump to con- meeting ran for four days, with 400 oral swim – most that fail die within a week To learn more about the World Seabird ningham says. ‘We need to figure out the climate change than warmer-climate birds. clusions about bird physiology when as- presentations in four parallel sessions or so of leaving the island. Young King Union, visit www.seabirds.net factors actually driving declines before we Most notably, Cape Rockjumpers and Pro- sessing the effects of climate change. ‘The and 200 poster presentations. also obtain no assistance from PETER RYAN can develop proper conservation meas- tea Seedeaters, species that live in the cool- main findings are that physiology, though ures to halt them. est parts of fynbos, have declined the most often considered the ultimate factor limit- ‘Fynbos birds are particularly important under recent warming. SABAP report- ing species distributions, may not be the gordon sprigg Scholarships in at the University of Cape Town in this regard because they live in an area ing rates of these two species dropped by factor responsible for warming-related de- that has been extremely stable, climato- 31 per cent and 32 per cent respectively clines in most fynbos birds,’ she explains. GORDON SPRIGG SCHOLARSHIPS are Applications must include a full Curriculum Vitae, logically speaking, for a very long time. So during the period under review. In the SCIENCEDAILY available to students pursuing postgraduate degrees certified academic transcripts and the names and changes in climate are not something they Cape Rockjumper, these declines occurred in Ornithology (MSc or PhD) at UCT. contact details of three referees. A copy of the research proposal, a letter of support from the UCT are used to. Furthermore, six of the species specifically in areas of its range that have Reference ELIGIBILITY Graduate students of any South African research supervisor and a detailed statement of we studied are endemic to fynbos, so if we warmed most rapidly in recent decades. Milne, R., Cunningham, S.J., Lee, A.T.K. and university who are in need of financial assistance. financial need must also be submitted. Scholarships lose them from this biome, we lose them In addition, the Cape Rockjumper is the Smit, B. ‘The role of thermal physiology in APPLICATION PROCEDURE are awarded for one year, with the possibility of altogether,’ she explains. only species whose decline is clearly linked recent declines of birds in a biodiversity hot- Applications must be made in writing to: The Director, renewal for a second year. spot.’ Conservation Physiology, November The new study profiles the well-being to a low physiological tolerance of heat, Percy FitzPatrick Institute of African Ornithology, Closing date for applications of 12 fynbos bird species based on a prompting the study authors to call for 2015 DOI: 10.1093/conphys/cov048 University of Cape Town, Private Bag X3, Rondebosch 7701 1 february 2016

12 african birdlife january/february 2016 news & views 13 news & views

Michelle Thompson from the University of Pretoria describes seeing a Southern Fiscal kill an adult African Pipit: ‘The dead pipit was too heavy for the fiscal to OUT ON lift, so it flew-hopped and dragged the display bird over to a barbed wire fence to eat’. I studied Southern Fiscals for two sum- White-browed Sparrow-weaver BIRDS IN killer mers in the Kalahari and several times ABUNDANCE saw my study birds labouring to fly out his and drooped his wings while carrying freshly killed full-grown slightly. The female remained in the same striped field mice. spot and also drooped her wings slightly. As South Africans we are blessed with an Despite their ferocity (or perhaps be- When the male eventually reached the abundance of beautiful birdlife. Whether you find moves yourself in a nature reserve, next to a river, in a cause of it), Southern Fiscals are not al- female, he half circled her until they were forest, camping or hiking; having a binocular ready Southern Fiscal ways successful in their more ambitious facing each other and again both raised is a must. The NIKON ACULON A211 is your ideal hunting endeavours and sometimes bite their heads. They swung their heads from birding companion with its comfortable grip and off more than they can chew. I once saw side to side for a while. The male then multi-coated lenses ensuring brighter images. a Southern Fiscal significantly misjudge moved behind the female, again held his the size of its target and crash - and tail and head vertically, and started to call feet-first into a Namaqua softly to her. The female lowered her body HERE ARE SOME OF OUR half-hidden in the long Kalahari grass. in response and this was apparently the TOP BIRDING SPOTS: The result was feathers flying and a very signal the male was waiting for, because iSimangaliso Wetland Park, KwaZulu-Natal, is startled sandgrouse bolting into the air, he immediately mounted her. The actual home to more than 530 species of birds. Declared while the chagrined beat a rapid copulation lasted only a second or two, af- as a World Heritage Site in 1999, it has the retreat in the opposite direction. ter which the pair flew away together. highest concentration of breeding birds in South The bird in this image was observed for At the start of their display, the White- The display of these White-browed Africa and sustains many coastal forest species. a couple of days by FitzPatrick Institute browed Sparrow-weavers both raised their Sparrow-weavers was sweet and gentle. Wakkerstroom, Mpumalanga, provides a large PhD student Davide Gaglio in De Hoop heads and tails. By comparison, that of the male Pin-tailed unobstructed field of vision and holds a variety Nature Reserve in September 2015. It Whydah, which regularly entertains us in of grasslands and wetland species. The area was using a hover-pounce technique to recent sighting made us realise that our garden with his energetic and jerky provides well-developed facilities such as bird hunt more conventional prey: large bee- we are sometimes far more famil- hovering display while trying to DAVIDE GAGLIO clubs, several bird hides and is home to many tles and grubs. The smooth white flanks iar with the courtship displays of impress his harem, is almost boisterous. globally threatened birds. iscal Shrike, Common Fiscal, branch or an overhead line. They only of the bird, with no sign of any chestnut exoticA birds, such as birds-of-paradise and Martin & Melanie Potgieter Southern Fiscal. This familiar bird hunt from cover when it’s really windy or feathers, identify it as a male. the moonwalking Red-capped Manakin, Bethlehem, Free State Ongoye Forest Reserve, KwaZulu-Natal, shelters has changed its name several times hot, because it is harder for them to spot Davide says: ‘I noticed this Southern than we are with some of our local, rather a spectacular 605 different bird species, many of inF recent years. Fiscals are widespread in food when on a perch surrounded by Fiscal hunting every day over a grassy more common species. I hasten to add that them rare and indigenous. Take your time in the diverse terrain admiring birds amid the lush forest, Africa south of the Sahara, and the lat- foliage. In fact, in the Kalahari, moving lawn kept short by grazing bontebok our familiarity with the courtship displays above the tree canopy and in the grasslands. est name change reflects new informa- into the shade to beat the heat can cut a and eland, at De Hoop Nature Reserve. of such exotic birds unfortunately does not tion about this complex group of species. Southern Fiscal’s hunting success by half. He was a creature of habit, always using come from first-hand experience, but rath- Klipriviersberg Nature Reserve, Gauteng, In 2011, FitzPatrick Institute researcher If the only available perches are low or the same tree branches to hunt from, er from watching numerous natural history boasts 215 species of birds and offers a network Jerome Fuchs discovered that all of the sparse, Southern Fiscals will sometimes and even repeatedly hovering in the documentaries. of hiking trails and guided walks through the ‘Southern Fiscals’ in South Africa were hunt while in the air. They hover and same place when he wanted to search for On 19 September 2015, after a day spent open veld and koppies. Spotting a beautiful bird the same species ( collaris) and then dramatically drop down onto their prey over the open grass. After watching birding at the Biddulphsberg Mountain while enjoying the scenery might just be what genetically distinct from fiscals found unsuspecting victims, many of which him for several days, one evening I tried Resort (near Senekal in the Free State), you need to fight your fatigue. north of about 15° south of the equator will never know what hit them. Other crawling carefully over to his favourite we were about to leave when we noticed (‘Northern Fiscals’). So the Jackie Hang- birds that hover and pounce in this way hovering spot on the lawn, hiding my- a White-browed Sparrow-weaver Ploce- man from the back garden in Cape Town include Rock Kestrels, Jackal Buzzards self by lying flat on the ground. Sure passer mahali, perched in a strange posi- or Pretoria is the same as the Southern and Black-shouldered Kites. Although enough, within two minutes of my ar- tion on a low sandstone wall. It took us a Fiscal with the white eyebrow from the diminutive by comparison, South- rival he was back hunting in the same moment to realise that there were in fact Kalahari – only with a little less make-up! ern Fiscals are easily as ferocious as place as always and I was able to take two birds and that a courtship display was Southern Fiscals hunt a wide variety of these raptors. Fiscals sometimes attack some intimate close-ups.’ in progress. small creatures from beetles and grubs to prey as large as themselves, or larger. SUSIE CUNNINGHAM They were about a half a metre apart mice, small reptiles and birds, with the and both were holding their heads and well-known caching behaviour of impal- tails straight up. The male then began CONGRATULATIONS! ing them on thorns to eat later. They like to sway from side to side and ‘dance’ his The ritualised courtship display ended in a The lucky-draw winner of the subscriber competition of a Wilderness Safaris to watch for prey from a high, open perch way very slowly towards the female (with holiday to Hwange, Zimbabwe, is Natasha Venter of Parktown North, Gauteng. brief mating, after which the birds flew away with a good view, such as an exposed lighter bill). While doing this he fluffed together.

14 african birdlife january/february 2016