About Me

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Canberra-based naturalist, conservationist, educator since 1980. I’m passionate about the natural world (especially the southern hemisphere), and trying to understand it and to share such understandings. To that aim I’ve written several books (most recently 'Birds in Their Habitats' and 'Australian Bird Names; origins and meanings'), run tours all over Australia, and for the last decade to South America, done a lot of ABC radio work, chaired a government environmental advisory committee and taught many adult education classes – and of course presented this blog, since 2012. I am the recipient of the Australian Natural History Medallion, the Australian Plants Award and most recently a Medal of the Order of Australia for ‘services to conservation and the environment’. I live happily in suburban Duffy with my partner Louise surrounded by a dense native garden and lots of birds.

Thursday, 28 May 2020

Mud, Glorious Mud

Yes, I know I've pinched that title from Flanders and Swan, but I promise not to mention hippopotamuses. I've pondered this post for some years, since watching swarms of parrots coming to the wonderful Blanquillo clay lick on the banks of the Madre de Dios River in the southern Peruvian Amazonia. It was an astonishing experience, travelling before dawn by river and on foot through the forest to settle into the most commodious hide I've ever been in, and seeing the birds come in waves to eat clay from the high river banks.
Red and Green Macaws Ara chloropterus gathering on the Blanquillo wall.
(And yes, I know they've got more blue than green, but I didn't name them.)

Here we can clearly see the huge macaws chewing on the clay.
Some of these birds may have travelled up to 100km for this moment.

A small section of the sumptuous hide, which extends well to the left of this photo.
The clay banks are visible below the hide.

Southern Mealy Parrots (or Amazons) Amazona farinosa.
The 'mealy' (and the species name) means floury, and refers to the abundant dusty powder down
in the feathers, used for preening. There are also some smaller Blue-headed Parrots present - see below too.

Blue-headed Parrots Pionus menstruus and Orange-cheeked Parrots Pyrilia barrabandi.
The names enable ready identification in the photo.
So, spectacular indeed, but why do they, and many other animals, do it? It's called geophagy, and it's a topic that's occupied many good scientists (and that's not including the surprisingly large field of human geophagy, which is well beyond the remit of this blog). To cut right to the point, it seems clear that there is no one reason for the practice, and given that it's undertaken by animals as varied as primates, antelopes, tapirs and butterflies, as well as parrots and pigeons, that's hardly surprising. Chimpanzees suffering from diarrhoea were observed to eat soils containing minerals similar to those sometimes prescribed to humans with the same ailment, but this is surely not relevant to the parrots. 

It comes down to two main lines of argument, each of which often claims to be the 'right' one. One involves the selective ingestion of essential dietary minerals, and there seems little doubt that this is the basis of much dirt-eating. Termite mound soil is particularly attractive to animals from elephants and giraffes to parrots and it has been shown that the mound contains far higher levels of organic material, as well as phosphorus and potassium, than the surrounding soil. Parrots visiting sites like Blanquillo choose clays that have high sodium levels relative to surrounding soils, and much higher than their fruit diet; sodium is rapidly leached out of rainforest systems far from the sea. This need seems to peak during breeding season, when birds are stressed. However in rainforest near the sea in Central America sodium is apparently more readily available and birds seemingly don't visit clay sources.

Butterflies widely indulge in sucking nutrients from clay - indeed there's a term for it, 'mud-puddling'. With the same proboscis that they use for extracting nectar from flowers, they suck liquid from wet soil, extract sodium in particular, and excrete lots of water. Here are a few, from both Africa and South America; sadly I can't offer you names for many of them - any assistance gratefully received!
An astonishing collection, including many of family Pieridae, from along the Manu River
in Peruvian Amazonia.
The Manu River banks in fact supplied probably the most dramatic butterfly watching I've enjoyed; here are some more.
Prola Beauties Panacea prola, top and bottom views.

King Swallowtail Heraclides thoas.
Iguazu Falls, especially on the Argentinian side, was pretty good for mud-puddling butterflies too.
Broad-banded Swallowtails Heraclides astyalus (top two and nearest the camera) and others.
Common Small Lemon Eurema deva, also at Iguazu.
More massed Pierids, including Small Lemons, Iguazu.

And lastly from Iguazu, this lovely Ruby-spotted Swallowtail Heraclides anchisiades.
 Ecuador is always fabulous; here are a couple of puddlers from Yasuní National Park.

Urania Moth, Urania sp.
(And the white outline looks like a bad bit of editing, but I promise I've done nothing to the image!)
And an African offering, from the wonderful Budongo Forest in Uganda.

But, back in the Amazon monkeys also chew on clay - and they don't seek out high sodium sources.
Venezuelan Red Howler Monkeys Alouatta seniculus nibbling on clay,
while putting their prehensile tails to good use.
What's going on here? This leads us to the other strand of evidence for dirt-eating. These monkeys, and many other animals, select fine-grained clays, with no interest in their nutritional values. Plants in general would rather not be eaten, and many carry some nasty toxins in the leaves to protect themselves. Fruits are intended by the plants to be eaten, so the seeds may be carried away, but only when the seeds are mature enough to germinate. Before that, not only are the fruits not luscious and sweet, but are often actively poisonous to prevent animals from getting in too early. Anyone who's gardened however knows that birds will often eat fruit before we want to or even could. One way that many animals escape these toxins is to eat fine clays which chemically bind up the nasties, particularly various alkaloids, to prevent them being taken up by the body, and perhaps to protect the gut wall from corrosive chemicals. This seems to be a widespread practice by leaf and fruit eaters.

Recently, from the marvellous viewing deck at the lodge on the lower slopes of Mount Kenya, we watched two very different herbivores availing themselves of the mud as medication.
Female Bushbuck Tragelaphus sylvaticus unambiguously eating the dried mud.
Speckled Mousebirds Colius striatus, which swarmed over the mud, picking up lumps to swallow.
Mousebirds, a wholly African Order of just six species, eat fruit and leaves almost exclusively -
as you'd expect from the mud-eating.
However you can do more with mud than just eat it. Many large mammals in particular wallow in it as an important part of their lives. The purpose is probably a combination of cooling off, getting protection from the sun (elephants, rhinos, hippos, pigs for instance have relatively little protective body hair), removal of parasites and protection from biting insects. Secondary social factors are doubtless also important.

African Buffalo bulls Syncerus caffer, known colloquially as 'dagga boys', the dagga meaning mud.
These were enjoying the wallow in Queen Elizabeth NP, Uganda.

Part of a large group of African Bush Elephants Loxodonta africana enjoying the mud after drinking
nearby in arid Buffalo Springs NR, northern Kenya.
This venerable cow in Murchison Falls NP in Uganda didn't get down into the mud, but sprayed it liberally on her back.
Galápagos Giant Tortoises Chelonoidis nigra relaxing in the mud on Santa Cruz, one of
the few places in the generally arid archipelago where a wallow can be reliably found.
And if you have the makings and the skills, mud is an excellent building material, as humans learned long ago. Some of the best exponents of this are the wasps, especially the potter wasps in the family Vespidae, but to my surprise I don't have any photos of their work! I must rectify that, but too late for this posting I'm afraid. Birds will now have to represent this aspect of mud. Members of several quite unrelated Orders have independently evolved the very specialised skill. Here are a few.
Pacific Swallow Hirundo tahitica actively collecting pellets of mud to daub into a nest,
Kuala Penya, Sabah, Malaysian Borneo.
And the handiwork of two Australian swallows, whose nests are as distinctive as the birds themselves.
The cup of  a Welcome Swallow Hirundo neoxena, familiar over most of Australia under eaves and in outbuildings,
alongside the distinctive bottle of a Fairy Martin Petrochelidon ariel.
Australian Magpie-larks Grallina cyanoleuca (male left, female on nest, with two chicks) near Canberra.
These are monarch flycatchers (quite separate from the South American monarchs) but
quite atypical in their mud nests, which are familiar in towns and around dwellings throughout
most of mainland Australia.
Some of the most impressive mud nests however belong to two Families of birds restricted to Australia and South America respectively. However while the Australian mudnesters comprise just two species, the South American ovenbirds have over 300, though most of them don't build the eponymous mud 'oven' nests.
White-winged Choughs Corcorax melanorhamphos (chick's head at left), Canberra.
Choughs and the related Apostlebirds are among the most strongly cooperative bird breeders in the world.

Rufous Hornero Furnarius rufus at its very impressive next in the Pantanal, south-western Brazil.
In Spanish (from where the bird got its English name, so don't worry that this one speaks Portuguese!)
horno is an oven, and hornero the baker.
So, I hope this introduction to some of the things you can do with mud has been of interest, even if you're not tempted to try all of them! Thanks for wallowing along with me.

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Thursday, 14 May 2020

Serengeti Sublime: #2 birds

Last time I introduced this superb park, one of the highlights of my natural history life - not least because of decades of anticipation! - and some of its non-feathered fauna. Say 'East Africa' and I imagine most people immediately, and quite understandably, think of the wealth of big mammals for which it is rightly famed. But it would be a bad mistake to overlook the even greater diversity of bird life, as a result of which this is a longer than usual post. However if you're reading this you may be predisposed to feel that the bit of extra time spent in this wonderful virtual bird world is worth it - and after all most of us do have some unaccustomed extra time on our hands these days!

One limitation on birding there is that of course it must be done from a vehicle, other than in the immediate surrounds of the lodges, the admin centre at Seronera and a few guarded rest areas. (I digress briefly to remember someone I met some years ago on a tour in Uganda; she proclaimed herself a 'free spirit' and grumbled about 'bureaucracy' trying to constrain her in the same way. It did seem to me that being trodden on by an elephant or eaten by lions might be more constraining than most bureaucracies, but that's just me. I don't mind going along with COVID-19 restrictions either.)

Notwithstanding such restrictions Serengeti birding is just splendid. It began soon after we passed under the slightly kitsch archway and entered the park, with our first bird soon after right on the roadside, thanks to our excellent Tanzanian driver/guide Geitan who spotted it at about 40kph despite its impressive camouflage. An astonishing feat.
Spotted Thick-knee Burhinus capensis; closely related to our rather more euphoniously-named stone curlews.
The South African term 'dikkop' sounds better too - until you realise that it means 'thick head'!
As the huge eye suggests, the bird is a nocturnal hunter, eating insects, mice and small reptiles.

The entrance station carpark - where we were able to get out - was very rewarding too, including a concrete bird bath which attracted a lot of interest (among the birds, and thus us). 
Black-lored Babbler Turdoides sharpei; this is a noisy gregarious bird, like the Australian babblers,
which are nonetheless quite unrelated.
Starlings in Australia (except for one native species in tropical Queensland) are exotic and frankly depressing.
In Africa it's very different.  Here's a gathering of Superb Starlings Lamprotornis superbus, an abundant East African
bird known affectionately as 'Super Stars' and much less common Hildebrandt's Starlings Lamprotornis hildebrandti.Hildebrandt's have red eyes, while those of the Super Stars are white.
Here's another impressive Serengeti starling.
Rüppell's Starling Lamprotornis purpuroptera, a striking long-tailed starling found across
East Africa, plus across the continent in Cameroon.
But back in the entrance carpark were a couple more treats to get us started. 
Beautiful Sunbird Cinnyris pulchella; and there's a tautological name!
However even by sunbird standards this one's pretty spiffy. It's found right across tropical Africa.
Silverbird Empidornis semipartitus, a glorious little Old World flycatcher; like us it too was having lunch there.
Elsewhere in the park natural water was, unsurprisingly, a magnet for many birds. Both Greater and Lesser Flamingos were present on ponds throughout.
Greater Flamingos Phoenicopterus roseus, above and below.
Male sandgrouse famously take water to their chicks out on the hot plains via their highly absorbent breast feathers. The eminent English ornithologist, the splendidly named Edmund Gustavus Bloomfield Meade-Waldo, reported this in 1896 but despite his formidable reputation his observation was scornfully dismissed until long after his death. I find this sad. This is only one reason I'm fascinated by these birds, and one of our highlights was the time we spent watching a large nervous flock of Chestnut-bellied Sandgrouse Pterocles exustus dithering and coming down to drink in small groups at a waterhole.
The lovely soft colours and patterns of sandgrouse are for camouflage out on the open plains,
including when they're sitting on a nest.
 Other birds were also attracted to this little waterhole.
Male Greater Painted-snipe Rostratula benghalensis (the female is more brightly coloured).
Not related to true snipe, the painted-snipes comprise three species (this one across Africa and southern
Asia, one in Australia and one in South America).
The Australian one is rare and very hard to see, so this was a real treat; it is uncommon, but not Threatened.
Collared Pratincoles Glareola pratincola breed in Mediterranean Europe and western Asia,
and spend winter in tropical Africa.
Coursers, in the same family, were also present nearby.
Three-banded Coursers Rhinoptilus cinctus are present all year round.
The most memorable watering place we found however was a small muddy puddle in a management track at the back of the Seronera visitors' centre and administration centre. In the middle of the day we watched a steady stream of small birds coming to drink and bathe. At least a dozen species came in to drink (five of which were new to me), most of them seedeaters, including all the drinkers below, which need to drink regularly, with others overhead and in nearby bushes. Mesmerising. 

Here are a few of them.
Black-faced Waxbill Estrilda erythronotos. This is in the same family as the Australian grass-finches.
Blue-capped Cordonbleus Uraeginthus cyanocephalus (also waxbills) and Kenya Sparrow Passer rufocinctus.
Red-cheeked Cordonbleu pair Uraeginthus bengalus (with another Blue-capped male).
(The bengalus name was applied in error; it is only found in Africa.)
Speckle-fronted Weaver Sporopipes frontalis, one of many weavers in the park, which
specialise in building large, sometimes communal (though not this one) grass nests.
I find this one especially dapper.
White-bellied Canary Crithagra dorsostriatus, a lovely dryland canary from east Africa.
Banded Parisoma (or Warbler) Sylvia boehmi, a pretty little Old World warbler of the
tough dry thorn scrubs of north-eastern Africa.
White-browed Scrub-robin Cercotrichas leucophrys, a busy friendly little Old World flycatcher
found throughout much of Africa below the Sahara.
Usambiro Barbets Trachyphonus darnaudii usambiro. Sometimes regarded as a full species,
but usually as a subspecies of D'Arnaud's Barbet. Barbets occur in Africa, Asia and South America,
but the barbets of each continent are now put into separate families. They are active hunters
of a wide range of small prey, but also avid fruit eaters. I think that collectively they merit
their own blog post here one day.
Here are a few more small birds from the park.
Immature male Scarlet-chested Sunbird Chalcomitra senegalensis; when he grows up he'll be
even more gorgeous! He was working the flowers in the lodge garden early one morning.
Grey-backed Fiscal Lanius excubitoroides. The fiscals are a group of African shrikes (fierce little hunters
of the family Laniidae) named for their mostly black and white plumage, apparently reminiscent of
the garb of the tax man (from Dutch or Afrikaans fiskaal). The details vary somewhat
according to the source.
Grey-crested Helmetshrike Prionops poliolophus, an attractive bush-shrike with a small range.
A small busy flock popped up alongside the car after we'd given up on them; I got just
this one shot off before they scooted off again.
Holub's Golden Weaver Ploceus xanthops, another lovely weaver, who we admired
from the lodge balcony while we had lunch.
Rufous-naped Lark Mirafra africana; Africa is full of larks (unlike Australia), which can
cause some identification angst to visiting birders. This species is quite short-tailed, but I'm sure this one is moulting as well.
Both species of oxpecker, Red-billed Buphagus erythrorhynchus and Yellow-billed B. africanus,on a giraffe - you can work out which is which! I am very happy with their juxtaposition here.
Oxpeckers separated off from the line that gave rise to starlings and mockingbirds some 20 million years ago.
Yellow-billeds specialise in picking large blood-engorged ticks off large mammals, while Red-billeds prefer tick larvae.
Female Pygmy Falcon Polihierax semitorquatus; males have a grey back.
This is an exquisite little falcon, less than 20cm long, which nests in a weaver nest chamber.
It's common enough in this part of the world, but always a delight.
Needless to say, there are plenty of birds of prey in this part of the world, and most of them are much larger. The wonderful big Bateleur is a common and very distinctive sight as it glides overhead, rocking from side to side - the word is French for a tumbler or acrobat.
Adult Bateleur Terathopius ecaudatus; the startling black and white plumage, broad wings, very short tail
and red bill and legs create an unmistakeable pattern. I think this one is carrying a nestling in its bill,
but I can't quite make it out.
And one of the sad stories of much of Africa is the decline of vultures. Alarming numbers are poisoned, by poachers treating carcasses (eg of elephants) to prevent the vultures attracting attention to them, and for the sale of body parts as talismans. Here are two, probably safe in Serengeti, but in trouble more widely.
Lappet-faced Vulture Torgos tracheliotos warming in the morning sun; this is a huge vulture
with a wingspan of nearly three metres. It is listed as Endangered.
The Rüppell's Vulture Gyps rueppelli is found right across Africa in the tropics, but is in
an even more parlous state than the Lappet-faced, being listed as Critically Endangered.
They are virtually extinct anywhere outside of national parks like Serengeti.
It is a lot easier to gain public sympathy for Cheetahs and Giant Pandas than vultures,
and it's a tragic situation.
And wherever we drove, there seemed to be larger birds on or near the ground, storks, bustards, spurfowl and francolins, hornbills - a true birder's cornucopia.
Abdim's Stork Ciconia abdimii, the smallest stork, which breeds right across the African tropics
but moves south in winter. This lovely bird found itself largely ignored (except by me!)
when it had to compete for attention with a Cheetah.
White Stork Ciconia ciconia. This is the celebrated chimney-nesting, baby-bringing
stork of Europe, which makes a long journey each year to spend winter throughout Africa.
It avoids flying over the Mediterranean, and flocks funnel through either the Straits of Gibraltar
or the Middle East.
Francolins and spurfowl comprise some 40 mostly African species within the family of domestic fowl, pheasants, quails etc. They are common roadside birds in Serengeti and many other parts of Africa.
Coqui Francolin Peliperdix coqui; a pretty grassland dweller of much of the southern half of Africa.
The Grey-breasted Spurfowl Pternistis rufopictus on the other hand is found only in northern Tanzania.
Black-bellied Bustard Lissotis melanogaster; this female lacks the male's black belly -
not that we can see it from this angle anyway!
White-bellied Bustard Eupodotis senegalensis; this time we do get the very handsome male.
It has a strange discontinuous grassland range from Senegal to Djibouti and South Africa.
Von der Decken's Hornbill Tockus deckeni is a smallish hornbill, but a striking part of the landscape
in northern Tanzania and into Ethiopia. They are quite relaxed around lodges.
Karl von der Decken was a German adventurer who travelled in East Africa and Madagascar in the 1860s.
And to finish (yes, really!) another very different hornbill, the great slouching menacing Southern Ground Hornbill Bucorvus leadbeateri which stalks the grasslands in small gangs, doubtless terrorising small animals up to the size of hares.
Male Southern Ground Hornbill; the female has a blue patch in the red throat.
With a wingspan of up to 180cm and weighing over four kilograms, they are larger than any of
the 'conventional' hornbills; the two ground hornbills are now regarded as comprising their own family.
So, Serengeti Sublime indeed; I shall never forget our days there. Thank you for letting me relive them with you, and I hope you've been inspired to see it for yourself one day. You won't be sorry.

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