Monday, 28 December 2009

Nature's Dustmen

Nature may be "red in tooth and claw", but it makes an awful lot of mess. Animals defaecate throughout their lives and then drop dead, plants litter the landscape with fallen leaves and great piles of dead wood. Fortunately, there are many animals, plants and fungi who specialise in the unenviable task of clearing all this up. Ants swarm everywhere and it is estimated that they form up to 20% of all animal biomass on land. The humble dung beetles are found on all the continents of the world except Antarctica, deriving all their nutrients and water from dung alone. They, at least, are recognised for the valuable public servants they are, and have been introduced into pasture land in Australia, South Africa and Europe to improve soil quality, and remove the habitat of various harmful flies who live in the dung.
But sometimes, more heavyweight refuse collectors are required.

Bird of the day

The Black Vulture

When I first came to Brazil I was surprised by widespread these birds were, soaring over the city of Belo Horizonte, or perched on street lights by the motorway in Vittoria. Throughout the states of Espirito Santo, Rio, Sao Paulo and Minas the only place I haven't seen them is the centre of Sao Paulo. They are conspicuous birds, with a 5ft wingspan and with a lazy overwatch flight, easy to see. Their close proximity to man is not, course, just chance. Just as kites infested medieval London, modern cities are a buffet for the vulture. Better yet, a buffet where the food is considerately laid out in an open air picnic, or dump. The hilly nature of the Mata Atlantica, with numerous rocky outcrops, suits the Black Vulture well, providing nesting and launching sites, but the natural forest does stifle them rather -their superb vision cannot penetrate the canopy. Some other species, such as the Turkey Vulture, cruise above the tree tops, searching for the scent of ethyl mercaptan from rotting bodies - and Black vultures follow them in and steal it.

Vultures are common, useful, and even quite majestic in flight, but they are not nice. They just.... aren't. When attacked on the ground they vomit over their attacker, thus simultaneously confusing him and lightening their flightload. In the hot tropical sun they defecates on their own naked legs, so that evaporation cools the blood. These droppings incidentally are so rancid they have been known to kill trees and other vegetation. Vultures can't even sing, lacking a syrinx, and communicate with hisses and grunts.

It is perhaps no surprise then, that in Mayan mythology the Black Vulture was associated with death. Their image is however positive in one specific area. The largest football club in Brazil, Flamengo, were long disparaged as The Urubus, or Vultures, by their enemies, presumably in reference to their black and red strip. This is now a source of perverse pride, and displayed at every opportunity!

Thursday, 24 December 2009

Night light

For someone brought up in the crowded south of England, the Mata Atlantica at night can seem incredibly dark. The distances involved, and the shielding effect of the terrain, combine to deny the familiar orange glow of distant street lights, and everything is the deep, deep indigo of night.

Well, not quite everything, there are little flickers of living light - bioluminescence.

Compared to most biological processes, bioluminescence is incredibly easy to evolve, requiring only an enzyme and substrate, the worryingly named luciferase and luciferin. Luciferase, at least in insects, appears to have evolved from a bog standard type of enzyme, the fatty acyl-CoA synthetases, whilst luciferin evolved from the substrates of these enzymes. Presumably because of the simplicity of this system it appears to have evolved on a multitude of separate occasions, in invertebrates, vertebrates, and fungi - about 90% of deep sea organisms, for instance, are believed to show some form of bioluminescence.

For those who would like a more in depth description there is an excellent review at....

Insect of the day

The brightest luminescent insect in the world, and a native of the Mata Atlantica, is Pyrophorus noctilucus. It is not a firefly, but a type of click beetle, and unlike the fireflies the light is on all the time, though it can vary the intensity. It has two luminescent areas just behind the head, and one normally hidden under it's wings, As you can see from the video, it gives the distinct impression of having headlights.

The intensity of the light is about 1/40th of that of a candle, and the peak wavelength is 540nm, conveniently the maximum sensitivity of the human eye. It has been claimed that the light is strong enough to read by (though you have to hold it VERY close to the page!).

Interestingly the related species in Jamaica, P. plagiophthalamus, has different varieties from yellow/green to orange, controlled by a single gene mutation. So not only can they find each other at night, they are colour coded!

Monday, 21 December 2009

Canaries and panettone in the hills

Imagine it's 1860, your parents are peasant farmers in the Veneto region of Italy, paying their taxes to the Austrian Emperor in Vienna.

Now, it's 1880, you are a peasant farmer in the same village, but paying taxes to Rome and the new Kingdom of Italy, except.... Romans and Tuscans have flooded your province, banning your dialect, taking the best jobs, and introducing new agricultural techniques that are putting your farm out of business. Then, salvation! You are offered huge expanses of land in the New World, subsidised travel, even subsided equipment, so you jump at the chance, and take your family for a three week cruise to the bustling port of Vitoria, Brazil. A few more weeks hiking from the coast to the hills and you are there - dense virgin forest in the middle of absolutely nowhere! Not what you expected, but you get together with your compatriots, pull up your sleeves, and set to work.

Millions of Italians emigrated to Brazil, especially to the southern states. By 1897, for example, there were twice as many Italians in Sao Paulo city as there were Brazilians! Today, over 13 million people here claim Italian descent in Sao Paulo state alone, and 65% of the state of Santa Catarina. Although the language of Brazil is still Portuguese, Italians have made a huge impact on the country, both economically and culturally. Three presidents have been of Italian descent, pizza and panettone are part of the national cuisine and "tchau" is the universal form of "goodbye".

In my area most of the Italians came from the Italian Veneto, seeking a new life. Many settled in the hills, establishing farms and forming towns like Santa Teresa, whilst in the next valleys Germans and Pomeranians were doing the same thing. This established a patchwork of forested hills and farmed valleys that is still found today.

Bird of the day
Possibly the nicest bird in Brazil, the Saffron Finch (Sicalis flaveola). Common and extremely tame it is perhaps the characteristic
garden bird in the hills around Santa Teresa, though relatively rare in towns and by the coast.
It even has a nice little song.

The landscape photo is courtesy of Heliana Pacheco

Saturday, 19 December 2009

Terror birding

If you fancy coming to see the wonderful wildlife of Brazil I have good and bad news. Firstly, there are many wonderful colourful and exotic creatures for you to see. The bad news is that the coolest are long extinct. Giant armadillos the size and weight of VW beetles, ground sloths the size of bull elephants that could rear up their hind legs, and the dominant predators, the superbly named "terror birds".

The Terror birds, or Phorusrhacids, were roaming the local hills from 60-2 million years ago. From 3ft to a massive 10ft high, with huge, strong beaks that could be deliver a blow with the force of a sledge hammer, and a kick that could break your leg, these were very potent predators. They couldn't actually fly, but when you can run 30 mph that's not such a problem!

It is tempting to let my imagination fly and populate the forests here with giant carnivorous birds, but actually my imagination doesn't have to work that hard, as anyone who has seem 10,000 BC will know. Ok, they didn't actually make survive long enough to be hunted by cavemen, AND they were never on the same continent as mammoths, BUT it is supposed to be quite accurate otherwise, and it's kinda exciting.
Perhaps slightly more authentic is this Discovery channel documentary.

Bird of the day

The closest living relatives of the Terror Birds are the seriemas, and one species still roams the neighbouring hills, the Red legged Seriema. Frankly, though, it's not actually that frightening, being only 30 inches tall. It's even less imposing when relaxing, as it sinks down to rest on it's knees and looks a little bit silly.
It can can fly, but would rather not, and will run up to 15mph when chased before it reluctantly takes to the air. It doesn't even nest in trees, and if it does nest in a large bush will jump rather than fly to get in it. How the mighty have fallen!

Thursday, 17 December 2009

Setting the scene

Well, welcome to my new blog! The plan for this is to make a record of the wildlife and flora I see around me, general impressions and interesting/ weird things that appear.

So first, I should set the scene. This is Brazil, but not the Amazon. Brazil is immense and has many ecosystems - rainforests, desert, marshlands and mountains. My home town, Vitoria, is on the Atlantic coast, and the native vegetation of my locale is Mata Atlantica, or Atlantic forest, with granite outcrops, the same as the states of Rio de Janeiro and Sao Paulo to the south. The weather is slightly seasonal, an average maximum monthly temperature and rainfall of 30.4°C/ 17.5cm in January and 24°C/ 4.4cm in July. This compares to 30°C/ 21.1cm and 33°/C 4.9cm in Manaus, capital of the Amazon region. and 8 °C/7.1cm and 23 °C/ 3.2cm for London (although of course the seasons in London are the other way round!).

So at it's coldest, it is like a summer day in England, at it's hottest, as Manaus is all year! There are also mangrove swamps, and some spectacular beaches on the coast.

Bird of the day

I wasn't sure whether to start with the very familiar sparrow, or the esoteric jacu, but I thought I would plump for the typical - the Bem-te-vi, or Greater Kiskadee. The Bem-te-vi ("nice to see you") is found all over the Mata Atlantica region, except the most highly urbanised areas such as central Sao Paulo - if you can't see one you will almost certainly hear it's loud, slightly mournful, "bem te vi" call. But sightings should not be a problem, they are highly tolerant of humans, and in fact seem to ignore us. They will fly in and out of restatements for food, and one pair I know has raised their brood in a nest perched just above a busy bustop by the university.
The Bem-te-vi is ominvorous and will eat fruit, but they don't seem to scavenge and prefer live prey. This can be of practically any sort, insects on the wing, small mammals, they will even dive for fish in shallow water. If it's small and it moves, they eat it. If it's bigger and moves, they mob it - Btv's will agressively attack raptors in a type of mobbing behavior if they feel threatened. Indeed it has been suggested that the similar colouring of a number of other South Smerican birds is a result of minicry, as BTVs are so scary, or alternatively, they just don't taste very nice!

The photo of the juvenille is from Ernest Bergmann.