Stunning Española, a Galápagos jewel; part 1

Little Española, in the far south-east of the Galápagos archipelago, is among the oldest of the islands (other than those that are already submerged, further to the east), eroding away into the sea. The whole archipelago of exposed volcanic peaks is riding the Nazca Plate towards South America; the youngest islands are the western ones, still passing over the 'hot spot' where fiercely hot magma is close to the crust's surface. Española's days (or millenia) may be numbered, but meantime it is one of the most exciting place for wildlife in the whole of the Galápagos, which is saying a very great deal! 

The location of Española is indicated by the red arrow; the volcanic 'hot spot' is currently under Isabela and Fernandina
to the west, and the whole archipelago is sailing east with the Nazca Plate.

There is so much to say about Española that I won't attempt to do so in one posting; it is probably most famous for seabirds, so let's start today with them. The Waved Albatross Phoebastria irrorata is the world's only tropical albatross and virtually the entire world population breeds on Española (there are a few breeding pairs on Isla de la Plata off the coast of central Ecuador). This is no coincidence; albatrosses rely on the wind (which is why nearly all species live in the permanently howling winds of the far southern oceans), and find it virtually impossible to take off from flat ground, because of their weight and hugely long wings. Only on Española is there flat ground for breeding alongside cliffs that face the prevailing winds for takeoff. When the winds fail in January and February they move closer to the mainland to fish.

The walking track - to which it is compulsory to keep - runs near the edge of the colony, but not close enough to nesting sites to cause problems. It is a remarkable experience to watch the great birds displaying to reinforce pair bonds, and to encounter the huge calm curious chicks, shabby as they moult into adult plumage.

Waved Albatross colony, Española.

They are a beautiful and imposing bird seen close up.

Courtship, above and below, involves exaggerated stepping, sky-pointing, mellow honking
and loud beak slapping, like children sword-fighting.

It requires some imagination to see the cheerful buffoonish chicks as the infinitely
graceful adults they will soon become.

To watch them lumber into the wind, or simply drop over the cliff edge, then soar overhead
or even below us along the cliff, is nothing less than thrilling.

And finally, if you were wondering about the 'Waved' part of the name, here's the answer,
in the delicate filigree pattern on neck, breast and flanks.

But when you can finally tear yourself away from the albatross colony there are other special seabirds to admire from close range too, including two species of booby. These lovely tropical gannets have been known as boobies in English for over 400 years; it is apparently derived from Spanish bobo, a fool, based on their trusting habits which enabled sailors to slaughter them with ease at breeding colonies. We really are shockers at times! Blue-footed Boobies are the ones most readily encountered throughout the Galápagos, though they are actually the least abundant of the three species - the other two however breed only on remote islands, so are less evident to most visitors. I can't ever imagine not stopping to admire the Blue-foots though!

Blue-footed Booby Sula nebouxii, Española.
The egg is just visible under the breast.

And fortunately Española is one of those remote islands, and supports a healthy breeding colony of Nazca Booby Sula granti. This is a primarily Galápagos species, formerly regarded as a sub-species of the more widespread Masked Booby Sula dactylatra.

Nazca Booby colony on plateau, Española.
They are bigger birds than the Blue-foots, and like the albatrosses appreciate the advantages of cliff-top takeoffs.

Nazca Booby pair.

Nazca Booby with eggs, Española. They nearly always lay two but, as in some other bird species,
the second chick is just insurance, and if its older sibling survives, it will not.

 Gulls are also present, both visitors and permanent residents.

Franklin's Gull Leucophaeus pipixcan, a non-breeding migrant from North America.
And what an excellent place to avoid the northern winter!
(Sally Lightfoot Crabs in the background.)

The exquisite Swallow-tailed Gull Creagrus furcatus on the other hand is essentially a Galápagos endemic,
with a small colony off the Colombian coast the only other breeding site.
It is also the world's only nocturnal gull; I remember my delight at looking out of the cabin window one travelling
night and seeing one flying alongside in the glow of the boat lights.

There is much more to tell you about Española however, and next time, more birds, plus mammals and reptiles!

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The Patagonia Picnic Table Effect

A week or so ago I got a phone call from an old birding mate, with the peculiar question "How many Australasian Bitterns have you seen this morning?". Very peculiar in fact - he knew as well as I that there have been no reports of this cryptic and extremely rare species in the Australian Capital Territory (ACT) for at least 70 years. In other words no living birder had seen one here. Needless to say work suddenly lost its importance and I drove across to the far side of town, to an urban wetland in the northern suburb of McKellar, to join half a dozen excited hard-core birdos watching this remarkable bird lurking, as they inevitably do, in the reeds.

Australasian Bittern Botaurus poiciloptilus, McKellar Wetlands, Canberra.
When I posted this pretty ordinary picture on the Canberra Ornithologists' Group's email line,
it was the first photo ever published of this species taken in the ACT.
There are estimated to be less than a thousand left in Australia, perhaps the same in New Zealand,
and apparently none surviving in New Caledonia.
I have had one record of this species on my life list, from about 40 years ago in the South Australian
deserts. It's worried me often though; was I good enough back then?, could it have been
an immature Nankeen Night Heron? Finally my conscience is clear!

While we were there, a White-bellied Sea-eagle drifted over. These magnificent birds appear regularly but sparsely here - not in the same category as the bittern, but certainly not an everyday sighting.

White-bellied Sea-eagle Haliaeetus leucogaster; not the McKellar Wetlands in the background,
but the Southern Ocean at Point Labatt, South Australia!

The next day, other birdos at McKellar found another bittern species, the tiny Little Bittern Ixobrychus dubius; this one is also commoner than the Australasian but is still very rarely sighted and officially described as a Rare Visitor here, though I suspect it could be resident in the ACT. Its habits and habitat make sightings very unlikely and infrequent.

This is as good a look as you're likely to get of a Little Bittern, and is also one I prepared earlier;
this time at Jerrabomberra Wetlands in Canberra a couple of years back.

So, from all this one might conclude that McKellar Wetlands is a veritable hotspot for unusual birds. Well maybe, but...

And here's where the Patagonian Picnic Table comes in. You may surprised to hear that the cold wet and windy far south of South America even has picnic tables! Well it does in fact, but we're not talking about that Patagonia, but a hamlet in Arizona, which has a roadside rest area with picnic table a little out of town. Back in the early 1970s a resting birder was delighted to come across the first Black-capped Gnatcatcher ever seen in the US (it is Mexican); in the ensuing rush, someone else recorded the first ever North American sighting of a Yellow Grosbeak (this must refer to the Southern Yellow Grosbeak), and then some other notable goodies.

So, did this mean that the picnic area formed fabulous habitat for rare species? Possibly, but almost certainly not - it's just that lots of experienced people looking for rare birds are going to turn some up from time to time, and when they do, more birders come and... well, you get the picture.  Had we not been gathered to revel in the Australasian Bittern, the sea-eagle would doubtless have drifted over without anyone noticing. Had not people been peering diligently into the reeds for hours, it is unlikely that the Little Bittern would ever have been noticed.

It happens in other fields too of course. A couple of summers back I was invited to see a very special orchid for our part of the world; the Horned Orchid Orthoceras strictum is only found in the ACT in a small area on Black Mountain near the city centre. I'd never managed to find it, so I was thrilled to finally see it for myself.

Horned Orchid, Black Mountain.
This is the only Australian member of the genus, with another in New Zealand.

Having enjoyed this for as long as we liked (once you've found them, they're easier than bitterns to keep track of!), we inevitably poked around, and of course the aura of the distant picnic table hovered over us. Firstly there was a colony of the strange Small Duck Orchid Caleana (formerly Paracaleana) minor. This is not so rare, but they're not easy to find, and I'd never before found this colony.

Small Duck Orchids, Black Mountain. Very ducky!

Finally, not far away again, another species I'd never managed to find - the Late Beard Orchid Calochilus therophilus, so called because it is the last of the genus to flower locally. This is a scarce member of a favourite genus of mine (we share an obvious adornment for a start), recorded from only three far-flung sites in the ACT.

Late Beard Orchid, Black Mountain.

Had we not been attracted to this site by the Horned Orchid, and probably had I not been with a couple of other skilled pairs of eyes, I'd never have seen the other two.

Perhaps too the reverse side of this phenomenon is displayed by the use of Where to Find... guides, and web sites. How often have we driven past rare and exciting animals or plants, because we're heading determinedly for the place to find them?

Anyway, it all got me thinking, and if you're reading this line it's probably triggered some interest in you too. Thanks for taking the trouble.

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On This Day, 21 June; William Paterson Died

Lieutenant-Colonel William Paterson is not much remembered these days in Australia, compared with some of his apparently less admirable contemporaries in the early days of the colony. I think that's unfortunate; while he was undeniably the wrong man for the job he was actually doing - he seems to have been most amiable and averse to conflict - his passion for natural history, and botany in particular, will always endear him to me. I'm happy to play my small part in refreshing our memories of him, to mark the 204th anniversary of his death.

Colonel William Paterson, 1799; artist William Owen.
Courtesy Art Gallery of New South Wales.

He was a Scot, born in 1755, who was always interested in botany from his boyhood, a passion apparently imbued in him by his father, a professional gardener. In 1777 Lady Strathmore from a neighbouring estate, who shared his love of botany, was instrumental in sending him to South Africa for three years to collect plants for her. Sadly for all concerned, during this period Lady Strathmore's husband died and she entered into an unfortunate remarriage to a man who not only disapproved of his new wife's botanical interests but took over her money and cut off Paterson's cash supply, leaving him grievously in debt. 

He enlisted into the army in 1781, probably to help alleviate his financial woes, but also to take him to new places and new plants. Based on his South African experiences he wrote the snappily titled Narrative of four journeys into the country of the Hottentots of Caffraria, which he shrewdly dedicated to Sir Joseph Banks, for whom he later collected plants in Madras. It seems in fact as though a major purpose in his life was to find favour with the great botanical patron. 

In 1789 he was made a Captain in the New South Wales Corps and given the task of both recruiting and commanding a company which he was to take to the New South Wales colony, where he arrived in 1791 and was immediately made commander of troops on that most brutal of convict outposts, Norfolk Island. His determination at this time was to collect a specimen of every Norfolk Island plant, as well as rock specimens and insects, during his 16 months of service there. Back in Sydney in 1793 he made one of the first attempts to enter the Blue Mountains by boat along the Grose River; with the knowledge of the time it wasn’t a silly idea at all, but he found that the waterfalls somewhat restricted navigation to the boat. He did of course make plant collections here including some hitherto unknown species.

Twining Fringe-lily Thysanotus patersonii Family Anthericaceae, Canberra.
This is one of my favourite spring flowers around here, named for Paterson in 1810,
the year of his death, by fellow Scot, the great botanist Robert Brown.

By now he was second in command of the Corps and for much of 1795 acted as colony administrator during the interregnum  before Governor Hunter arrived. While always apparently scrupulous and ethical himself - he later died in poverty - he notably failed to rein in the corrupt practices of those under his command, who were widely and publicly trading in spirits. 

In 1796 he went home on sick leave with an eye infection, taking plants for Banks and advising him on trees to be planted in the colony. He was elected a Fellow of the Royal Society, made Lieutenant-Colonel and sent back here as Lieutenant-Governor to Governor King in 1799. Of these honours I suspect that he most prized the fellowship as he had previously sought it but been advised by Banks to wait until he had proved himself further. 

When the arrogant and ambitious disgraced soldier John McArthur tried to embroil Paterson into his personal dispute with the governor over his rights to make money however he chose, Paterson was offended and fought a duel with him, in which Paterson was wounded in the neck. McArthur was arrested and sent back to England. Paterson recovered and collected new palms, hibiscus and ferns on the north coast. He took a personal interest in the collections of Matthew Flinders’ botanist Robert Brown when they visited Sydney in 1803 and accompanied the French zoologist Peron in the field when the mighty Baudin expedition dropped in.

 

Patersonia glabrata, Ulladulla, New South Wales.
In 1807 Robert Brown (see previous caption too), named this lovely and
widespread iris genus for Paterson.

Although ill-health forced him to relinquish most of his duties, when London wanted to set up a colony in northern Tasmania to thwart any intentions that the French may have had, they selected Paterson to command the colony. With him were his wife, 66 soldiers (including two drummers) and 74 convicts. He changed sites a couple of times until he finally settled on the current Launceston site – Australian historical doyen Manning Clark refers to him as an ‘amiable procrastinator’. This was probably not the best personal characteristic for a man in his senior position, especially with the catastrophic events occurring in Sydney in early 1807, where Governor Bligh seemed to have lost the plot entirely. It wasn’t that his priorities – of banning rum as a trading medium and concentrating on self-sufficiency in agriculture in preference to relying on wool and other trade – were bad in themselves. Rather it was the powerful enemies this made, and his arrogance, obscene tirades against all who opposed him and brutality to those in his power. 

Bligh was arrested and deposed, and it was a reluctant Paterson who as Lieutenant-Governor finally had to return from Launceston to take over. This was after all, going to interfere rather severely with his plant collecting! Himself a target of Bligh’s abuse, he took the mutineers’ side, and ordered Bligh to leave the colony. His year of command while waiting for Governor Macquarie was frankly disastrous. Ill and drinking to cope with the unwanted pressures, he gave away land to anyone who requested it, and left effective control to the officers who'd deposed Bligh. When the time came for him to go back to England to participate in the trial of the mutineers, he was cheered aboard by a huge crowd of citizens as a ‘benevolent and likeable man’ in Manning Clark’s words. Sadly he died soon after while rounding Cape Horn.

 

Patersonia occidentalis, Bee-keepers Nature Reserve, Western Australia.
This is the only western member of the genus.

I suspect that if Paterson had not joined the military he could have had a happy life as a plant collector, with Banks' patronage, but life sent him on a much less happy path. Nonetheless he made the most of his opportunities to contribute to our knowledge of Australian botany and natural history in general, though well out of his depth in his day job. I wish things had worked out better for him, but life's not like that - and at least he lived to see his name perpetuated in a flower genus that he would have known well.

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Featuring the Fabulous Figs

This is another in a sporadic series on my favourite tree groups, triggered perhaps by seeing the beautiful  Desert Figs growing on rock faces in the central desert ranges recently.

Desert, or Rock Fig Ficus brachypoda (formerly known as F. platypoda), John Hayes Rockhole, East MacDonnell Ranges, central Australia.
This species also grows in wetter tropical areas to the north, but survives in the relatively humid situations
of the desert ranges.

Desert Figs often grow in apparently impossible situations, sending roots down for metres
from where the seed lodged to find soil and eventually a water table. This distorted tree
is at Ellery Creek Big Hole, West MacDonnell Ranges.

This stunted specimen has sent roots out, mostly in vain, searching for sustenance.
Kings Canyon Rim Walk, George Gill Range.

And this one is in an even more exposed situation, surviving somehow in sand on top of the plateau
above Palm Valley.

This is just one species - and in terms of habitat an atypical one - among some 900 Ficus species, found throughout the world's tropics. This makes it one of the largest plant genera in the world and it is an ancient one, hence its very wide distribution. One characteristic is the milky latex, which in Ficus elastica produces a rubber (though this is not the Rubber Tree Hevea brasiliensis, from Brazil).

Another is the fruit, which apparently led figs (specifically Ficus carica) to be the first cultivated plant, known from sub-fossils of sterile figs (which could only have been produced by cultivation) from 11,000 years ago in what is now Palestine. 

Desert Fig fruits, Kings Canyon, George Gill Range, central Australia.

These fruits are not what they seem; in fact they are a cluster of numerous tiny fruits, enclosed, like the flowers from which they form, on the inside of the 'fruit'.

Fallen fig 'fruit' - the actual tiny fruits and flowers are visible on the inside of the casing,
which is comprised of the fused stems of the fruit.

The pollinating wasps hatch inside the infructescence - to give it its formal name - and feed on special infertile flowers before mating. The males die, never seeing the world outside their fig. As the females leave they collect pollen from the male flowers near the entrance, and take it to another fig which they pollinate while laying their eggs. It's up to you if you want to think about that when you next bite into one...

Many fig plants, including the Desert Fig, belong to a fig group called Banyans, or Strangler Figs. Stranglers are mostly rainforest figs which start life when a fruit is deposited by bird or fruit bat on a tree branch or rock face high above the ground, then sends down roots to find ground. They are not parasites, but will eventually kill the host tree, not by 'strangling' but by shading out its canopy, denying it essential sunlight. 

This Small-leafed Strangler Fig Ficus obliqua still contains the trunk of its host tree,
clearly visible through the root network.
Chichester State Forest, New South Wales.

More Small-leafed Stranglers from Chichester State Forest (above and below).
They have become huge dominant trees in their own right, with their own massive crown and load of epiphytes, especially (in the photo above) Birds Nest Ferns Asplenium sp.

Eventually all trace of the doomed host tree disappears, as its trunk rots and the fig 'fills in' the gap.

Small-leafed Strangler Fig buttresses, enclosed now so that the host is completely gone.

These aerial roots can become massive if they simply descend vertically without following the host's trunk. One of the most famous such trees is the Curtain Fig Ficus virens near Yungaburra on the Atherton Tableland, tropical Queensland.

Curtain Fig; the remarkable curtain formed when the host tree toppled sideways to lean against a neighbouring tree.
The fig went with it, putting down roots to the ground from all along its angled trunk
and eventually taking over the new host.

In some banyans these aerial roots provide props which allow the tree to spread out to cover vast areas. One specimen of the Indian Banyan Tree Ficus benghalensis was recorded as growing on a palm tree in the Kolkata Botanic Gardens in 1786. By 1911 the palm had long gone and the banyan covered nearly a hectare, supported by over 500 trunks.

Roots becoming supporting trunks, Moreton Bay Figs or Banyans Ficus macrophylla, Lord Howe Island.

So far all the illustrations are of Australian figs, but as I mentioned there are species throughout the tropics.

Figs and Euphorbias dominating woodland east of Masindi, Uganda.

Fig fruit, Inca Track above Machu Picchu, Peru.

Almost wherever you are reading this there are likely to be figs, either natural or cultivated. They deserve our unreserved appreciation.

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Naturally Green

It's been a while now since I offered one of my intermittent series on colour in nature. The last two series were on yellow and blue. I mention these specifically because both are essential to understanding green in animals. Among vertebrates in particular, green pigments are almost unknown (like blue), and what looks green to our eyes is a clever sleight of hand (or eye), almost universally formed by a combination of yellow pigments (especially carotenoids which, as mentioned in the earlier article, must be obtained from plant material) and structural blue. In very brief, this involves light scattering by appropriately sized 'bubbles' in feathers or skin which reflect only blue light - there's a lot more detail in the earlier posting, linked above.

Musk Lorikeet Glossopsitta concinna, Coles Bay, Tasmania.
The lorikeets are little nomadic blossom specialists, all basically green.
(They are also shameless with regards to colour coordination!)

Like virtually all green birds, the lorikeets' feathers are really yellow, with blue light reflecting through them, which our eyes interpret as green. Presumably green confers camouflage protection in foliage - though in the case of the parrots, the contrasting other colours (mostly pigments) might seem to defeat that purpose! Here are some more examples - enjoy!

Mulga Parrot male Psephotus varius, inland Western Australia.
These stunning little parrots are found throughout much of the Australian inland -
not just in Mulga, woodlands dominated by Acacia aneura.

Yellow-crowned Parrots (or Amazons) Amazona ochrocephala and Mealy Parrots A. farinosa,
Blanquillo clay lick, Peru.

 

Spotted Catbird Ailuroedus melanotis, Atherton Tablelands, tropical Queensland.
An apparently 'primitive' bowerbird which  doesn't build display bowers.

Western Violaceous (White-tailed) Trogon Trogon chionurus, Cerro Blanco Reserve, Ecuador.
For non-Americans, trogons are one of the most delightful surprises in the neo-tropics.

Crimson-rumped Toucanet Aulacorhynchus haematopygus, Paz de las Aves, Ecuador.
An exquisite tiny toucan, sometimes seen at fruit feeders.

The principle applies not just to birds however. Frogs, despite famously being green (though most aren't!), have no green pigments either. Their skin structure is very complex; blue frogs have a layer of dark melanophores, overlaid by iridophores that reflect blue light. Green frogs have a layer of yellow pigmented xanthophores on top of that - extraordinary! But clearly to those frogs that possess it, green is an important colour to be.

Litoria moorei, Margaret River, south-west Western Australia.
This beauty is known as the Motor Bike Frog for its remarkable call.

unidentified tree frog, Bwindi Impenetrable National Park, Uganda.

I believe that green reptiles get their colour thus too, though I'm not sure that much work has been done here.

Amazonian Racerunner Ameiva ameiva, Manu National Park, Peru.
Widespread in the neotropics, and introduced into North America.

Green tree snake Thrasops batesii, Limbe Botanic Gardens, Cameroon.

Many green butterflies too rely on yellow pigments and reflected light to achieve the effect; the microstructure of butterfly and moth scales is extraordinary.

butterflies, Manu River, Peru.
Million of butterflies congregate on the river banks, where their coiled proboscises
are as useful for taking up water as nectar.

Splendid Ghost Moth Aenetus ligniveren, Namadgi National Park, above Canberra.
This moth astonishes me - both wings and fur are green, both achieved by bending light to suit its needs.

beetle, perhaps a cockchafer, subfamily Melolonthinae, on Acacia, Leeuwin Naturaliste NP,
south-western Western Australia.
I am confident that this too relies on light diffraction.

What I am uncertain of with regard to the beetle is whether pigment is also involved, or whether a different wave-length is being reflected, so that it is green, rather than blue light being bounced to our eyes. Certainly several bird groups use this more direct approach to produce green. Here are some examples.

Rainbow Bee-eater Merops ornatus, Fraser Island, Queensland.
Australia's only bee-eater, but a pretty nifty one!

Dollarbird Eurystomus orientalis, a roller, and also our only species; they are closely related to bee-eaters.

Rufous-tailed Hummingbird Amazilia tzacatl, Ecuador.

Broad-billed Motmot Electron platyrhynchum, southern Ecuador.
Motmots are also in the same order as bee-eaters and rollers, probably not a coincidence that they
share this green-producing mechanism.

Emerald Dove Chalcophaps indica, Lord Howe Island.
Many fruit doves share this characteristic too; this one is found from India to Australia.

A very few birds however do produce their own green pigments; best known are the wonderful African turacos, which manufacture turacoverdin, a copper-based porphyrin, from fruit. The turaco reds, turacins, are derived similarly; it has been calculated that the feathers of a red and green turaco contain some 20mg of copper, to derive which some 20kg of fruit must have been eaten, which would take two to three months! Clearly he is making a statement.

Touraco page from Birds of Western Africa, Borrow and Demey, Helm Guides.

It has recently been recognised that a few other birds - some jacanas and pheasants, and the Indonesian Crested Wood-partridge - also produce turacoverdins.

Another class of chemicals, biliverdins, are also utilised by some animals as green pigments - mostly these are invertebrates, but they are used in some fish bones that are green (!) and oddly, in emu and cassowary eggs!

Emu eggs, south-western Queensland.

Grasshoppers and mantids also employ biliverdins.

unidentified grasshoppers:
Currawinya NP, south-west Queensland (above),
and Mt Kupé, Cameroon (below).

Praying Mantis, subalpine Namadgi National Park, above Canberra.

And finally, for today at least, some of the many green caterpillars take their pigments from the degradation products of photosynthesis that they eat - a useful camouflage tool.

Hawkmoth (?) caterpillar, Uluru National Park, central Australia.

It may or may not be easy being green, but it's certainly a complex process becoming so!

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