Friday, 23 December 2011

The Nativity Bird

Adoration of the Shepherds by Charles LeBrun 1689

All over the Christian world at this time of year you will see Nativity scenes - Jesus, Mary and Joseph in the stable. In the background there will be horses, and perhaps sheep brought by the shepherds, but one crucial animal is missing, one that undoubtedly was flitting around the stables of Bethlehem, the sparrow.

Sparrows (Passer domesticus) originated in the Middle East, and it would have practically impossible to keep them out of a stable. They would probably roost there, and later in the year there would be sparrow nests in the eaves. Where you have one sparrow you have several, being very gregarious little birds. Even in Biblical times they were so familiar as to be taken for granted - in the Gospel of Mathew, Jesus notes how (even) the flight of a sparrow is noted by God.

So common then, and common now, probably the most widely distributed bird in history. They tied their destiny to humans many many years ago, and it's worked. They flourish wherever man does, in his cities and on his farms. But why?

Firstly because they like cereal seeds, and man grows cereals, and make bread. But beyond that they are extremely adaptable. Whilst many birds are picky about nest sites, sparrows will nest almost anywhere, although they prefer holes in trees. The eaves of buildings are common, and almost any dense tree or shrub, but even street lights, apparently attracted to the warmth.

This brings us to the sparrow's 2nd advantage. They are immensely tolerant, "a bold and cheeky bird, but very wary and difficult to approach closely" according to my copy of the Ladybird Guide to British Birds (1956)*. Unlike many birds the noise and confusion of a modern city simply doesn't seem to bother them. Add an above average intelligence, a robust immune system, high fertility and amazing longevity (up to 23 years in captivity and even 19 years in the wild for one Danish bird) and you see why there are so many of them.

And, they're cute. They're tame and friendly and nice to watch. This is more of an evolutionary advantage than you might think. Sparrows were deliberately released into the Americas, in Brooklyn in 1852 and Buenos Aires in 1870, apparently as the teeming European immigrants missed having them around - they're now found from the Northern Territories of Canada to Tierra del Fuego. They are the commonest birds, with pigeons, in many Brazilian cities, from Porto Alegre in the south to Ipatinga in Minas Gerais, and they have even reached the edge of Amazonia.
Where there is man, there are sparrows.

So when you imagine the Nativity scene, shepherds, kings and a baby gurgling in the manger, add a few little brown birds flitting around in the background.

*Brian Vesey-Fitzgerald. The third book of British birds. Ladybird

Wednesday, 21 December 2011

EVERYTHING you ever wanted to know about the plants of the Amazon

A 353 page book has just been published, Fruit Trees and Useful Plants in Amazonian Life.

A co-production of the Food and Agriculture Organization (FAO), the Center for International Forestry Research (CIFOR) and People and Plants International (PPI) it aims to describe all the commercially or medically important plants in the Amazon region, and it is amazingly comprehensive.

For example
For the Buriti Palm (Mauritia flexuosa) there is a description of it's ecology, how they can be cultivated, the average yield (up to 360 kg per tree in a year!), economics (1 litre of Buriti juice costs about $1) and a COMPLETE guide to it's possible uses, including how to make traditional toys.
There is a description of the cultural significance of the plant, the animals that eat the fruit or nest in the branches, and even a recipe for Buriti frozen creme! All illustrated with line drawings.

And, the guide is free! It can be found at...

Friday, 16 December 2011

Nasty little spiders

The prime time news on Brazilian channel Globo recently showed a report on spiders*, specifically "Aranhas marroms", or "brown spiders" (translations never sound so impressive!). These little spiders might not look much, perhaps a bit larger than a normal spider, but they are a big problem.

"Brown spiders", (mostly Loxosceles similis) are found through out Brazil, from Para down through Minas and Sao Paulo to Rio Grande de Sul, with the southern state of Parana being something of a hotbed. However, unlike many spiders, the young don't make silk parachutes to travel on the wind and they've only got little legs, so they don't travel very far - colonies tend to be very dense, but localised. They're timid animals and will generally try to hide from humans, but 5,000 people are bitten each year, leading to fevers, skin lesions, and even death. So why is such a little spider so dangerous?

Well, it's all to do with their venom, which is incredibly toxic. Unlike some snake venoms, it's not neurotoxic as such, so victims don't go into paralysis or spasms, it is necrotic, which means that cells just die. Depending on how good a bite it got in, this can cause a little lesion the size of a bottle top, to one up to 40 cm wide. If this gets infected, or the toxin is carried in the blood stream to other organs (which is rare) the consequences can be very serious. The bizarre thing about their venom is that whilst some mammals such as rabbits and humans are very susceptible, mice and rats aren't, goodness knows why.

So what to do?


Virtually all cases of bites have been from spiders forced into close contact, by someone picking them up, or they were in clothing or shoes, so shake out any clothing. Don't, what ever you do, spray them with insecticide! It causes a nervous reaction making them very aggressive and much more likely to bite!


If you suspect you've been bitten, wash the site with soap and water, but don't try to squeeze or suck out the venom, you'll just spread it around. Go straight to a doctor, with, if possible, the spider - treatment is by anti-venom and it helps to know who bit you!

Every year, specialised (and very brave!) teams go out hunting around the southern city of Curitiba and catch thousands of spiders, which are "milked" for their poison. This is used to make the anti-venom. about 20,000 doses per year, to be distributed to hospitals all over Brazil.The actual technique used to make the anti-venom is explained nicely in the Globo piece.

Be nice to geckos

The principle predators of brown spiders are geckos, which presumably are immune to their toxin.

* The news report can be found here....

Wednesday, 26 October 2011

Little monkeys

These charming creatures are "saguis" (marmosets), in fact "Saguis de cara branca", White headed marmosets (Callithrix geoffroyi). One of the tamest wild animals, they are great favourites of tourists, eagerly taking fruit in their little hands. Without tourists, they have to fend for themselves, groups travelling up to 2 km through the forest. They eat fruit and any small creatures they can find, insects, snails or even frogs. They also eat a surprising amount of gum from trees and lianas, either gouging wounds in trees or searching for wounds made by insects. Gum apparently has a lot of carbohydrates, so it is sweet and gives lots of energy to little monkeys.

And saguis are little, which means they need lots of high energy food, but they can turn out to be food themselves. Hence the frequent nervous glances up to detect any eagles or falcons. Mothers carrying young seem to settle for fruit and gum, hunting for tasty insects takes too much attention, and they are too ungainly to bolt if needed. If predators appear there are basically two options. If they see a raptor, there is a brief cry and then they freeze still under cover. But if it is not immediately dangerous, a cat on the ground for instance, they will mob it - harassing it from above as a group and making loud "tsik" calls. Strangely, it has been shown that being part of a "mob" actually reduces rather than increases monkey stress - it is tempting to extrapolate that to humans!

One curiosity of saguis, and other new world monkeys, is that some individuals are trichomatic, and some dichromatic. What does this mean? Humans and higher apes have three different colour cells in their eyes, in combination they can distinguish up to 1 million colours. Most mammals have just two types, so can distinguish only about 10,000, kind of equivalent to colour blindness. So why are some monkeys one type, others another? Apparently trichromatic monkeys are better at finding fruit, especially when its red, but dichromatic monkeys see better in the low light of dawn and dusk, so it all balances out in the end.

Saturday, 22 October 2011

The Owl of Buenos Aires

No, this is the "other" Buenos Aires, a pretty valley in the hills above the Brazilian coastal town of Guarpari.

On a visit there I saw various birds flitting around, from finches to a circling eagle, but the one that really caught my attention was this Burrowing Owl (Athene cunicularia - say "cunicularia" and you will see how it is a good name for an owl!).

I have blogged about Burrowing owls before ( , so for now, here are just some pictures.........

... and his (her?) burrow

Friday, 14 October 2011

..... Not really

There are some creatures that live on the edge of reality, from Bigfoot to the Loch Ness monster. Brazil has it's share too.

The Mono Grande, Didi or Maricoxi

The Wild Man of the Woods. There have been reports of "ape men" in the Amazon region since the days of the conquistadors, Pedro de Cieza de Leon reporting Indian legends of them in 1533, and Francis Drake recorded similar rumours. "Sightings" have surfaced every now and again since. There was even a photo published in the Illustrated London News in 1929, and a scientific name suggested (Ameranthropoides loysi).

Reports have been remarkably consistent from 1769 onwards. The Mono Grande are apes about 5 ft tall, more or less upright and covered in short dark hair. If angry they throw sticks, or their own faeces in one report (which might be more effective). It has to be said that these reports have not been universally accepted, or at all in a serious sense. The fact that these forests are home to both Indians who are about 5ft tall, and spider monkeys who are 3ft tall but covered in short black hair, has not gone unremarked.
As an aside, one of the most popular comedians in Brazil goes by the name "Didi".

The Mapinguari, Mapinguary or Isnashi

Once upon a time Brazil was home to giant ground sloths. It really was, their fossils have been found. They were very successful and spread throughout the Americas, some weighing up to 5 tons and with a reach of up to 17ft if standing on their hind legs.

Recreation of a Giant Sloth (conveniently with red hair) at Iowa Natural History Museum

It is suggested that some of these are the mapinguari (or mapinguary or Isnashi ) a large, noisy, smelly and red haired animal supposedly found in the rainforests of Brazil & Bolivia, the "fetid beast". The mapinguani has powerful arms and long claws, and can stand on its rear legs when threatened, which is very giant sloth like. After all, radio carbon dating shows they were still around in at least 2,700 BC (on Cuba), not so long ago, or maybe the mapinguari could be a folk memory passed down from that time. One intriguing connection is that the mapinguari is supposedly bullet (or at least arrow) proof and giant sloths had hides toughened against predators with small bony plates.

Giant Anacondas

Ok, these actually exist. The term "anaconda" refers to a group of similar snakes, but is usually used for the Common Ananconda (Eunectes murinus) which can be up to 22ft long, which is pretty impressive,
It's really hard to actually get a good measurement for various reasons. Firstly, anacondas are aquatic and so are difficult to see, or recover if killed. And to be measured they pretty much have to be killed, as 22ft of muscle is really hard to capture and hold in a straight line. Secondly, specimens don't preserve well, and skins can stretch up to 50% in the drying process.
But the ones we are talking about are bigger - much bigger. The renowned Britsh explorer, Percy Fawcett, reported in 1907 killing one measuring 62 ft long, and he had been told by a Brazilian Boundary Commission official of one in the River Paraguai of over 80ft. Through the 1920s, 30s and 40s there were various claims to have seen snakes of 60-70ft long though no hard evidence.

Percy Fawcett and the Giant Anaconda

Two little asides. Several witnesses report that, in addition to it's great length, the snake had glowing eyes, visible when the snake was underwater. Fawcett also comments on the awful stench, which local Indians claimed had a stupefying effect.

The Minhocao

Basically "Big Earthworm" in Portuguese, and that's what it looks like, a gigantic earthworm about 1 metre thick and up to 25 m long, with small horns. It is capable of taking cattle and of ruining orchards with its burrows. During the late 19th century there were reports from as far apart as Parana, Goias and Uruguay, mostly in waterlogged ground by rivers, but little since.
Now, there are creatures called caecilians, basically carnivorous legless amphibians which burrow in damp ground, and they can be up 5ft long. A large one of these and a very active imagination could maybe produce the Minhocao.

Legendary beasts of the Guarani

The Guarani are a tribe from the interior of Brazil, to the south and west. Their pantheon of gods includes some interesting examples of, er, speculative biology, such as ...

The Mboi Tui

The "snake-parrot" is just that, a huge snake with the feathered head of a parrot. He lives in marshes like the Pantanal and lets out a terribly loud squawk if disturbed. Actually, the Mboi Tui is just one of lots of "feathered serpents" found in American legends, Aztec and Mayan temples are full of them. If you want to look at it one way, this is suggestive of a shared folk memory - or cultural drift, take your pick.

The Ao Ao

The Killer Sheep. A huge animal resembling a sheep or peccary. Unfortunately it also has a large pair of fangs and is completely carnivorous. The Ao Ao eats only man, chasing its prey with a howling "Ao Ao Ao". It is implacable, chasing its chosen prey relentlessly until caught - climb a tree and it will dig to undermine the roots until you fall. Should you be faced with an Ao Ao the only way to escape is apparently to climb a Palm tree, as it dislikes these and will go looking for other prey.

More details on the cryptozoology can be found at.... The CryptoWeb web site

Sunday, 2 October 2011

Pigeons Everywhere

If you visit Rio for the World Cup or the Olympics you will see many beautiful and exotic sites, but one very prosaic one - pigeons. Even on Copacabana you will not see the ubiquitous seagulls of Northern Europe, but pigeons picking at the remains of ice creams and sandwiches left by tourists. They seem to quite like resting on the sand.

A pigeon on Copacabana beach

Brazil has various "pigeons", for instance the little Ruddy Ground Dove, but here we are talking about the Rock Dove (Columba livia), one of the most successful species in the world. They probably evolved in South Asia, but spread rapidly, fossil evidence showing that they have been in Israel, for example, for over 3,000 years. The first recording in the Americas was in 1606, in Nova Scotia, and they were later introduced through the Americas as domesticated birds. They are now virtually ubiquitous in towns and cities in Brazil - a recent study in the southern city of Porto Alegre found them to be the 2nd commonest bird, after house sparrows.

Why so successful?

a) Tolerance
Man isn´t always tolerant of pigeons, especially when they are eating his crops, but pigeons are extremely tolerant of man. How many other birds would by happy in the noise and confusion of Trafalgar Square? This allowed their domestication early in human civilisation, but also opened up a world of opportunity for wild pigeons. It didn´t hurt that cities are, to a pigeon, very similar to the cliffs their ancestors evolved in, so there are plenty of nest sites.

Pigeons on a castle wall in Tonbridge, England

b) Adaptability
Pigeons are the dogs of the bird world, in the sense that they have a huge potential for variation. Darwin noted this, devoting a whole section in the first chapter of The Origin of Species to differences in domestic pigeons - "the variation of the breeds is something astonishing" although "I am fully convinced that the common opinion of naturalists is correct, namely, that all have descended from the Rock Pigeon (Columba livia). "

So pigeons are adaptable, especially in....
c) Food
Pigeons are basically seed eaters, but as everyone knows, they will eat more or less anything. This is one of the reasons for their success, and results from a very forgiving digestive system which can cope with high carbohydrate or high protein food.

d) Temperature
How on earth can the same species be happy on a scorching Copacabana beach at 40 C and a bitterly cold English city at 0 C?

Pigeons in Reading, England in February. Happy?

The wonderful adaptability of pigeons spreads to thermoregulation, so that they can adapt themselves to temperatures even up to 60 C.
"Normal" birds will pant to lose heat, but adapted ones evaporate water from their skin. It´s not sweating as such, but they actually change the structure of their skin so that it has a much greater blood supply and is more hydrated. On the other hand, in the cold pigeons form an extra layer on their skin to stop evaporation, as well as eating even more than normal. Actually, pigeons prefer it warm as they can spend less time brooding baby pigeons and more time feeding (and so make more baby pigeons).

Flying rats?

It has to be said that communal nesting and a lack of delicacy over food does come at a price. Concerns have been raised over the hygiene, of pigeons, given that guano tends to be a prominent feature of their local environment. For example, 10 out of 33 pigeon droppings studied in in the city of Vitoria had Cryptococcus neoformans, a cause of fungal meningitis. On the other, these were old, dry, droppings, and the birds themselves when examined, er, intimately, they did not have the fungus, nor did other ones in Fortaleza. In other words, the guano had not been cleaned away and was just somewhere for the fungus to grow. So it could be argued (perhaps not very convincingly) that this is a lack of human rather than pigeon hygiene.

Pigeons probably do itch quite a lot. A study of 14 nests in the city of Manaus in the Amazon collected over 10,000 arthropods over 12 days, mostly mites. This was actually less than would be found in other parts of the world, probably because the local parasites have not quite adapted to pigeons yet.

How to have less pigeons

A pigeon having a drink on Copacabana

Various raptors will take pigeons. They form a large part of the diet of the Black chested buzzard (Buteo melanoleucus) and are taken by the Stygian owl (Asio stygius) and other hunters, but this is not exactly a control strategy. Spikes or wires to prevent perching work well locally, but just shifts the problems. The fashionable solution at the moment is bait treated with a contraceptive, and this is now being used around the world. A study in Ljubljana, Slovenia, found a 24% reduction in numbers over 3 years. Interestingly, the pigeons that remained were healthier, with fewer parasites.

But the problems of urban life not withstanding, pigeons have been valued by the Egyptians, the Romans, and rulers of ancient India and Iran through history, and they are one of the most successful species on the planet. Perhaps we should pay them a little more respect.

Saturday, 20 August 2011

How not to get eaten by sharks

A recent Ecoratorio twitter directed me towards a BBC article on sharks and how to avoid them ( As a public service I thought I would pass on the highlights.

Sharks prefer some places to others
Places where the shelf drops suddenly, river mouths for example. Just don't go there.

Don't look like food
Sharks generally won't attack humans except by mistake, once they realise their mistake they'll back off, which is why most people are only bitten once. Of course it's a bit late then.
Don't swim in murky water - they won't realise their mistake until too late. Equally avoid dawn and dusk.
Don't splash about a lot, to a shark that signals a wounded (and therefore vulnerable) animal.
On the same subject, don't wear bright or shiny objects, it attracts them.
Swim as a pair or group, it's more intimidating.

Mind games
You can generally tell a shark's mood by it's body language, aggressive or languid. If it's in a bad mood, leave.
Don't do anything to annoy them (obviously)
You can, sometimes, face them down. Keep eye contact. Never turn your back on a shark.

Last resort
There are documented cases of sharks being dissuaded by a punch on the nose, even when they have an arm or leg in their mouth. Some authors recommend the eyes or gills. Probably best not to rely on this though.

Sharks in Brazil

The Pernambuco coast near Recife. What lies beneath?

There are various sharks along the Brazilian coast, but only three considered dangerous to humans, the Bull shark (Carcharhinus leucas), Tiger shark (Galeocerdo cuvier) and Blacktip shark (Carcharhinus limbatus). The first two are sometimes found off the Espirito Santo coast, but shark attacks there are virtually unknown. Actually, it is technically possible to encounter a Great White, but you would have to be so incredibly unlucky that either this or a falling meteorite would get you.

The situation in the north of Brazil, around Recife, is different, Tiger and Bull sharks flourish in the warm water. Even this did not use to be a problem, but in the last few decades shark attacks on humans have increased, probably due to disturbance to their traditional habitats along the coast by over fishing and the building of a new port complex.

"I went to Recife and I returned!" "I'll get you next time!"

It´s still pretty rare to become shark food though, with only 47 attacks between 1992 and 2006, although admittedly that did involve 17 fatalities. The bad news is that sharks don´t use toothpaste, wound infections are common. Over 80 different human pathogens have been isolated from shark mouths. Whether the sharks get food poisoning from us is unrecorded.

Saturday, 6 August 2011

Old Man's Beard

The Vila Velha state park in Parana is well worth a visit, with it's spectacular sandstone rock formations. Matching the bizarre geology are tumbles of grey vegetation hanging from the trees - this is "Barba de velho" / Spanish moss (Tillandsia usneoides). It is not actually a moss, but, perhaps strangely, a type of bromeliad, and grows on trees from where it can absorb nutrients and water from the air or from rainfall.

Tilandsia has long thin stems with thin, curved leaves up to 6 cm long, the whole plant hanging down for up to 6m in a tangled mass. It does produce seeds from tiny inconspicuous flowers, but it can also spread from stem fragments that blow in the wind or are carried by birds onto convenient tress.

You would have to be pretty desperate to try and eat it, the leaves are wiry and covered in tiny scales, but it does have its uses. Traditionally it was used to stuff mattresses, and even form cloth. In modern times it has found a role as a bioindicator of air pollution. Plants are transplanted from clean to test areas where they absorb heavy metals from the air (but, crucially, not from the soil) for later analysis. You can even get an idea of what type of air pollution is the problem, for instance Zinc, Barium and Calcium are indicators of traffic pollution (it used to be Lead, but not any more), whilst Cobalt and Mercury can come from metal processing plants.

Figueiredo et al 2007. Assessment of atmospheric metallic pollution in the metropolitan region of Sao Paulo, Brazil, employing Tillandsia usneoides L. as biomonitor. Environmental Pollution 145 279 - 292

Tuesday, 26 July 2011


The bay of Sao Francisco do Sul in Santa Catarina, southern Brazil, is a calm and tranquil place, but when we visited on Sunday there were one or two dangers to be aware of. About 30 jellyfish had washed up on the beach.

A study in 1999-2002 found that 76% of jellyfish stings in Santa Catarina* occured at times of high southerly winds, when they are driven inshore from the deep sea. Jellyfish are known locally as "agua vivas" or "living water" and you can see why, these extraordinary creatures are virtually transparent and don't resemble any other creature.

But scattered around the beach these foot wide disks were also rather reminescent of land mines, and that too has some sense, they pack a powerful punch. Stinging cells known as nematocysts inject powerful toxins and they can cause intense pain, as anyone who has been stung can testify. This is how they kill their prey. Several jellyfish on the beach had dead crabs attached, but whether they had been caught out at sea, or killed trying to feed on the beach, it was hard to say.
If you are stung you should wash the wound, but not with fresh water, this will burst any nematocysts still in the wound. Vinegar works, but yes, the urban myth of using urine will also work too at a punch. Better is go to a hospital and get an injection of dexamethosome.

Which species these are I cannot say, but the commonest on the beaches of Santa Catarina is reported to be Olindias sambaquiensis* - hopefully so as it only causes relatively mild, local, symptoms. Unless you are a crab.

*The occurrence of jellyfish stings on the Santa Catarina coast, southern Brazil
Resgalla et al 2005. Brazilian Journal of Oceanography, 53, 183-186.

Saturday, 9 July 2011

Strawberries from the hills

When you think of Brazilian fruit you maybe think of oranges (they are the world's largest producers) or pineapples. But there are also more European fruits, especially in the south or up in the hills. When immigrants came from Germany, Pomerania or north Italy they bought their tastes, and their farming skills, with them, so there are apples, grapes, and strawberries. So much so that the town of Domingo Martins actually has a Strawberry Festival each August.

It has to be said though that Brazil is not a major player in the world of strawberries ("morangos"), producing 40,000 tonnes in 2005, which sounds a lot until you consider that Spain produced 320,000 in the same year, and the US 1,050,000. Still, theres a big domestic market, and strawberries are regarded as a high value crop.

Strawberries are not annual plants and will flower for several years, but yield goes down each year so thats not what is usually done. Runners, little plants on the end of stalks, are cut off and replanted each year. You can grow strawberries from seeds, but again it's not very commercial.

There are lots of varieties of strawberries, bred for flavour, or different conditions. The main difference though is if they are destined to be eaten fresh, or used as food flavouring. In Brazil, half of all strawberries are destined to be eaten directly, half to be used industrially. Here's a breakdown of some of the commonest varieties.

To be eaten fresh

Campinas – named after a city in Sao Paulo state and a major growing area. Good size and flavour and tolerant of angular leaf spot, but vulnerable to antracnose and verticillium wilt

Vila nova – early maturing and very productive with an intense flavour, that allows them to be used industrially as well. Resistant to many things but vulnerable to grey mould (Botrytis cineria).

Tangi – vigorous and resistant to spider mites, but late maturing and only averagely productive. The fruit are more pink than red and with a slightly acid flavour

Oso grande – highly adaptive vigorous plants with large leaves. Large fruit, at least at the start of the flowering season.

Selva – not the best, irregular fruit and it's susceptible to many common Brazilian diseases

For flavouring food

Santa Clara – very vigorous with a good flavour, but the fruit are of uneven size and shape. Quite disease tolerant.

Burkley – vigorous, matures early and very productive, but the fruit have a sour taste if eaten fresh and susceptible to mildew.

Mangrove mayhem

For much of the weekend the Brazilian town of Vila velha will be without water. The culprit is a burst pipe which has to be replaced, necessitating the closure of much of the town's water supply.

Now, the pipe runs through an old mangrove swamp. Mangrove mud is stuffed full of bacteria. Mangrove trees produce about a kilo of litter per metre per year, which has to be broken down, not to mention debris from fish, crabs and shrimp which make a rich organic soup. In fact, there are so many bacteria that the available oxygen is used up and anaerobic bacteria (which can survive without oxygen) flourish, including those called “sulphate reducing bacteria” - these are the ones that produce hydrogen sulphide, the “rotten egg” smell. Unfortunately, the smell is not the only problem.

The action of anaerobic bacteria causes corrosion on the surface of metal objects. Additionally, the waterlogged soil of a mangrove swamp is high in iron pyrites, and when exposed to oxygen this forms sulphuric acid. As the water level in coastal mangrove swamps goes up and down with the tide and through the seasons, sometimes aerobic, sometimes anaerobic, metal there gets attacked from both sides.

The pipe in this case was made of 1 cm thick cast iron, and laid about 30 years ago. Gradual corrosion and water pressure inside the pipe eventually caused it to burst so it had to be replaced, but as it was now 6m below ground (due to a landfill project) that was easier said than done. Hence the chaos!

Saturday, 2 July 2011


It has just been announced that the small Brazilian state of Espirito Santo, part of the Mata Atlantica region, is the 4th largest rubber producing state in Brazil, with 14,000 hectares of “seringueiras”, or rubber trees. Most of the rubber latex produced is bought up by two cooperatives and sent to Michelin, who process it and turn it into tyres. There is a state plan to expand to 75,000 hectares by 2025.

What does this mean for the countryside? Well the rubber tree, Hevea brasiliensis, is native, sort of. Actually it comes from the Amazon rain forest, but grows well further south, as long as it is below 800m and with less than 1,000 mm of rain per year. It is very vulnerable to frost so needs north facing slopes (this is the southern hemisphere remember) and tends to be susceptible to fungi, though there are resistant varieties.

It is a tall tree, up to 144ft if given it's head, but normally kept to 80ft to encourage latex production. This means that it doesn't start producing rubber until about 5-6 years old – only 8,000 hectares of the 14,000 in Espirito santo are actually producing. Because of this young plantations are usually combined with cash crops such as pineapple or papaya, or animals such as goats. Even perennial crops such as coffee or pepper.

When the tree has reached the end of it's useful life you can of course use the wood. But, frankly, it's main advantage is that it is very cheap. It warps easily, and is very liable to rot, so cannot be used out doors. If you see something made from “parawood” or “Malaysian oak”, beware!

Saturday, 28 May 2011

Life, a little further away

This is stretching the definition of "natureza" somewhat, but it is kind of interesting.

Just recently an international* group announced the first "possible" life supporting planet, Gliese 581d**. Not that it DOES have life, just that it could. Gliese 581 is in the constellation of Libra, about 2 degrees north of the brightest star there, Beta librae - look high in the sky, more or less due East from Vitoria, Brazil at 9 o'clock at night at the moment.

At first sight Gliese 581d, orbiting the red dwarf Gliese 581, doesn´t look very much like home. For a start it is about 5-7 times bigger, but more importantly it receives only about 1/3 as much sunlight as Mars, let alone us, so any water there should be frozen solid. It also probably orbits with one side always facing the sun, so has a permanent dark side. However, computer modelling shows that it might be a little more complicated.

A computer simulation of Gliese 581d

A dense atmosphere heavy in CO2, which would match planets in our solar system, would act like a blanket - the famous greenhouse effect. This would raise surface temperatures above the melting point of water, so you would have liquid water, which is essential for life (as we know it).

So what would it be like there? Well, pretty dark at the best of times, and maybe completely dark in some places, with what little light there is being red from the red dwarf star. Lots of CO2 in the air so we probably couldn't breath without masks, and we would feel very heavy, gravity being about twice what we are used to.

Another simulation - we just don't know what it looks like yet

All this is speculation, but it might not be much longer before we know more. Gliese 581d is not that far away - well, it is, 20 light years, but relatively not that far. So probably before long telescopes will be good enough to get at least a light spectrum which would tell us a lot about the atmosphere, especially if it's green!

And... there might be another way. In October 2008 a group in Ukraine beamed a message directly to Gliese 581 using a high powered radio telescope, it should arrive in 2029. An answer would arrive in 2049.

* A French/ English group led by a Swiss using a telescope in Chile. Wordsworth et al 2011, Astrophysical Journal Letters

** It doesn't have a proper name yet, nor does the star. Any suggestions?

Thursday, 19 May 2011


This is taboa (Typha dominguensis), a common perennial reed. Very very common! Actually, it has spread to tropical and temperate regions all over the world, in marshes and wetlands, even mangrove swamps. It shoots up to about 2 metres tall and releases millions of seeds, so it quickly takes over any area where it becomes established and can be something of a nuisance.

A coastal Restinga marsh near Vitoria, Brazil

Has it's uses though. The fibre is tough and durable and can be used to make baskets and handicrafts, even paper. In Turkey the flower stalk is applied to burns and wounds and apparently works quite well.

Releasing seeds

Perhaps it's most beneficial property though is as a sponge. As it grows, taboa absorbs vast amounts of material from the water around it, most of which accumulates in it's tissues. So taboa beds can absorb Phosphorous from agricultural runoff which would otherwise cause algal blooms, or even heavy metals like Zinc from mining pollution. You just wait and then cut and take away the reeds. There are several studies around the world deliberately making lagoons of Typha dominguensis as a low cost way of cleaning waste water.

It's hard to say whether taboa is such a benefit environmentally. It swamps (as it were) native species in clean water, but cleans polluted water so that other creatures can survive, as well as providing cover for insects and small fish. Anyway, it can be very useful for us humans.

Saturday, 7 May 2011


It´s autumn in the southern hemisphere, but it feels like spring with the appearance of flowers and suddenly quite a few butterflies ("borboletas"), the most common of which seems to be this one...

I managed to identify it as the Mangrove Buckeye (Junonia evarete) thanks to the excellent field guides from fieldmuseum org ( ). As its name suggests, the Mangrove Buckeye rather likes mangroves, in fact from Florida to southern Brazil it is a bane of attempts to reforest coasts with these trees, the caterpillars stripping young seedlings. It's not just mangroves though, caterpillars eat Gervao (Stachytarpheta cayennensis), also know as "Brazil tea", and Sempre viva (Paepalanthus polyanthus) as well as others.

With this diverse food range it can be found far from the coast and mangroves, from Belo Horizonte in the inland mountainous state of Minas Gerais, to Brasilia, over 700 miles from the sea.

Adult females and males can be easily told apart as the males have blue patches (top) whilst the females are more discrete (above). Both have a fast and fairly erratic flight and reportedly prefer the small flowers found in grassland by roads or recently neglected land, certainly I saw these on flowers amongst long grass.

Sunday, 17 April 2011

Hunter in the Night Sky

Look to the south and you will see the Southern Cross and Alpha Centauri, but look away from there from November to February and the most conspicuous constellation you will see is Orion, possibly the best known constellation on the planet! Conspicuous and visible from all over the Earth, everyone, from the ancient Egyptians to the Aztecs to the Aboriginal Australians has Orion in their mythology

As everyone knows, Orion is basically four stars, the arms and legs of the Hunter, surrounding his "belt".

A screenshot from Stellarium, 8pm 15th April

The bright red star is Betelgeuse, the strange name coming from the Arabic al-jauza (the name of the constellation) and abet, meaning centre or armpit, so Betelgeuse means "Orion's armpit". Be that as it may, Betelgeuse is huge, if it were placed in the centre of our solar system its surface would extend out to Jupiter. Huge, but not long for this universe being a decaying super giant - when it finally explodes it should be visible from Earth during daylight.

Opposite Betelgeuse is the blue star Rigel, the brightest star in the constellation. Again named from the Arabic, Rigel is a shortened form of Riǧl Ǧawza al-Yusra, which means basically "Orion's left foot". Actually Rigel is two stars, a binary system, which is why it's so bright.

The Belt, three stars together in a straight line, has many names. In Latin America it's known as the Three Marys, a reference to the three biblical Marys who came to the sepulchre of Jesus in the Gospels and were companions of a 4th Mary, the mother of Jesus. Mary Magdalene, Mary of Cleopas and Mary, mother of James. Of course the three stars of the belt are nowhere near each other, they just look that way from here. The star in the middle, Alnilam, is actually 375,000 brighter than the sun, but perhaps fortunately, is 1340 light years away.

The other two stars are Saiph and Bellatrix. Saiph again has an Arabic name, a corruption of saif al jabbar or "Sword of the Giant". It looks faint to us but that's because us humans cannot see UV light, in fact it's as bright as Rigel, but much hotter and most of it's light is ultra violet.

And lastly Bellatrix, the "Amazon star". Bellatrix is "Female Warrior" in Latin, and technically the star is an "eruptive variable" - thus this is perhaps a fitting name for the extremely dangerous, though barking mad, adversary of Harry Potter.

Tuesday, 12 April 2011

A New Rat

The world always needs more rats (doesn´t it?) and so you will pleased to know that a new one has been discovered! Drymoreomys albimaculatus is orange, hairy and lives in trees.

Actually, Drymoreomys albimaculatus are very, very, rare, even one of the authors of the paper describing them had never seen a live one. They live on the eastern slopes of the Serra do Mar, in the coastal Brazilian Atlantic rainforest from São Paulo down to Santa Catarina, at altitudes of 650 to 1200m. Which means cold damp forest with winter temperatures down to below 0 C, which is probably why they have unusually long thick fur. Although all the ones that have been caught were on the ground, they probably climb trees as they have long prehensile tails and special pads on the palms of their paws for climbing.

Drymoreomys means forest mountain rat, and albimaculatus refers to the white spots they have in their orange pelt. And that's about it. Their life cycle, predators, place in the ecosystem is a mystery. Goodness knows what they eat, probably everything, rats aren´t usually fussy.

Sunday, 10 April 2011

The Sky at Night

The night sky of the Mata Atlantica can be as impressive as it's wildlife, and as difficult to see. Of course it depends where you are. By the coast, the tropical heat and humidity tends to cause clouds at night, even after after a day of burning blue sky, whereas in the mountains the clean air and lack of ambient light can open up a vista of millions of stars, or valleys silvered by a brilliant moon.

But to a northern European, the sky is strangely unfamiliar. Orion is still there, but the other stars are rearranged in new patterns. How to identify them? One way is the excellent Stellarium program I have been playing with recently, a free download from The beauty of it is that it's completely customisable. Open the menu by passing your cursor to the left hand side and under [location] input your coordinates and a 360 view of your night sky at that moment will appear (you can find your coordinates in various ways, but the easiest is probably to just put your town/village's name in wikipedia). Find the star you are interested in and click on it to give a name and some basic info. You can also set it up to show the planets automatically, arrange the stars in constellations, increase or decrease the level of background light pollution, and many more things.

So what did I see? The first thing I tried was to ID a constellation I've seen many times from my south facing balcony, but never found in any books. That was because it is in fact 2 constellations, one of which is the most famous of the southern hemisphere.

The Southern Cross is part of the culture of Brazil, on the flag and even the name of a major football team, Cruzeiro. Trace a line from Gacrux, the red one, across to Acrux and extend it about 4.5 times and you are looking, more or less, due South.

Of course the constellations are an optical illusion, Beta crux is 350 million light years away whilst Gacrux is "only" 88. The red colour of Gacrux comes from it being a red giant, a huge, but dying, star, the colour giving it the local name of Rubidia, or "ruby like". In contrast Delta crucis is known as "Palida" or the "pale one". The two pointers, Alpha and Beta Centauri, are technically part of the constellation Centaurus, but on a hazy night, or with lots of ambient light, they seem much more part of a tail to the "Y" of the Cross. Alpha Centauri is very bright, and for two reasons, it's actually three stars, two of which orbit around each other, and one is the closest star to Earth, at 4.2 light years away. Because it is so close Alpha Centauri is found in all sorts of science fiction, from Lost in Space, via Babylon 5 to Avatar, but of course these stars are also found in local mythology, showing local priorities. For the Xingu indians, the Southern Cross is the Curossow bird, whilst Alpha and Beta Centauri are a bird trap.

Saturday, 26 March 2011

A life on the ocean waves

Fly to Brazil from Europe or Africa and you will pass over thousands of miles of ocean. As you look down on the endless waves you might reflect on life below - perhaps you imagine you see a whale spouting, or a fishing boat trawling for cod. If you've already experienced Brazil and it's teeming millions of insects, you might wonder if there are any of those down there too. In fact, in all the world there are only 5 species of ocean going insects, all from the same genus, Halobates, and only one of these H. micans, is found in the South Atlantic.

Dias & Lopes 2009. Occurrence, distribution and abundance of Halobates micans Eschscholtz, 1822 (Heteroptera, Gerridae) along the southeastern Brazilian coast. Braz. J. Biol. vol 69.

Halobates micans, the Sea Skater, is in the same family as the pond skaters, and you can see why, with it's long legs and antennae. They live in a purely 2 dimensional world, they can't fly and die if immersed under water for long, though they cover themselves with water repellent and are covered with tiny hairs which trap air, so they are very buoyant. Instead of flying or diving they skate across the sea surface at up to 1m per second, hunting for prey. Well, very small prey, as their bodies are only about 5mm long, so plankton, or perhaps fish larvae trapped on the water surface. The weak link is egg laying, for which they need a solid object. This can be hard to find in the open ocean and they will use anything, really anything, seaweed, dead jelly fish, lumps of petroleum. A plastic gallon jug was found to have 70,000 eggs attached!

Zoologische Staatssammlung München Halobates micans; Eschscholtz, 1822; Meerwasserläufer, Wikicommons

Sea skaters seems to be fairly common, though not near the coast, or too far south where the water is cold. But why does he have the whole south Atlantic to himself? After all there are plenty of insects living in fresh water. Well, salinity is a problem, although the salt marsh mosquito, for example, can tolerate 3x this level. Worse maybe is the problem of breathing. Insects need access to air, at least occasionally, and the rough and tumble of the ocean may drive their little bodies too deep into the ocean for them to return. This is maybe why the only insects there are restricted by super-buoyancy to the surface.

The ocean can, from above, appear like a desert, but for Halobates it's actually worse. Most desert animals can burrow into the sand to escape the heat of midday, or predators, but Sea Skaters are stuck on the surface with nowhere to hide. The sun burns down, with levels of UV that would fry most creatures, but Halobates is shielded by a layer of very dark UV protection in it's upper cuticle, which blocks pretty much all UV light. Then there are fish and sea birds attacking from below and above, which Sea Skaters avoid by jumping several centimetres into the air, away from the water surface.

Put all this together and you start to see why, of over 1,000,000 insect species, there is only one in the vastness of the South Atlantic, the little known Sea Skater, Halobates micans.

If you can lay your hands on Antenna, the journal of the Royal Entomological Society, there is an excellent article on Halobates there. Alternatively, there is a good web resource at