Sunday, April 29, 2007

Animal Encounters XIIX

The Giant Tortoise

The male giant tortoise at Bristol Zoo Gardens is currently at the centre of a very exciting debate. Previously it was thought to belong to a species called the Aldabran giant tortoise, but in the last few years, it has been suggested that it may be a survivor from a species that was thought extinct - the Seychelles giant tortoise (Dipsochelys hololissa). Their lifespan is at least 100 years, possibly up to 150. The Zoo's male is thought to be over 80 years old - a survivor from an almost extinct species. Giant tortoises grow steadily for the first 40 years of their lives and, given enough food, can weigh up to 254 kg. The head and legs are much too big to be completely withdrawn into the shells. The shell does not need to serve as protection from predators because there are no predators on the islands where they evolved.

I eat.....

Little is known about Seychelles giant tortoises in the wild, because none are believed to be alive in the wild. The Aldabran giant tortoises still survive in large numbers on their island home, largely free of predators and competitors. They graze grassy areas on the island in large numbers. There are over 100,000 on the island of Aldabra. So many graze the grass on the island that the grasses themselves have adopted a special low-growing form to avoid being killed completely by the tortoises. The tortoises start to feed early in the morning, before it is too hot, when the dew is thick on the grass. By mid-morning they are still feeding, but now with their heads faced away from the sun to keep their heads cool. By midday, they have stopped feeding and have taken refuge in the shade of the few trees on the island. By late evening they emerge once again to feed. They eventually stop feeding after the sun sets, falling asleep wherever they happened to be feeding, ready for the next day.


Tortoises are usually silent, although mating males make a hollow groaning sound that can be heard hundreds of metres away.


Giant tortoises were found on all islands in the western Indian Ocean until Mauritius was colonised in the 1600s and an increasing number of settlers and explorers visited the Seychelles islands removing and killing tortoises. It was thought that all Seychelles tortoises became extinct around 120 years ago, with the exception of the Aldabran species, until reports of oddly-shaped captive tortoises prompted a re-examination of their identity. In 1998, staff at Bristol Zoo Gardens were excited to find out that their giant tortoise may be one of these individuals in question. After examination, the experts suspected that this tortoise was a Dipsochelys hololissa, of which there may be fewer than 40 individuals left in the world. Experts are still debating. The Nature Protection Trust of the Seychelles has set up a breeding programme to ensure the survival of this rediscovered species.


Did you know that the name Dipsochelys means 'drinking tortoise' - named because they have a special flap inside their head that allow them to suck water up their noses continuously without raising their heads. Aldabra is such a dry island that drinking quickly and efficiently like this is an important survival technique.


Saturday, April 14, 2007

Easter Eggs & More .....

Well, I know its a week since easter and two weeks since my last posting, but what can I say? Time flies...especially when you've been busy. And I have been busy for the past two weeks. At work, I've just started my internal secondment to another department as part of my training. The cost management department is where I'm doing my secondment for the next 3 months. So far, I've just been tasked with the counting of light fittings :-( I hope things will get more interesting in the next couple of weeks.

For the easter weekend itself, three friends from Spain came to visit me. Hence I was a tour guide for three days. I took them around Bristol and Bath, seeing the sights, sounds and delights of the west country. And we were blessed with perfect weather for the whole weekend! David, one of my Spanish friends, told me that it was raining heavily in Spain and they were all really surprised at the sunnyness of England. It should really be the other way round! I also showed them the nightlife of Bristol, and for those two nights that they were here, we met some pretty surprising people around town......pretty twin sisters (imagine that! Twins!), a group of pirates (mostly females!), and some others. All in all, it was very enjoyable.

David, David & Juanjo

And today, I test rode the world's largest capacity motorbike, the Triumph Rocket III. It is the biggest, most bad-ass motorcycle money can buy! The specs are awesome, a 2.3-litre engine producing almost 150ft lb of torque, pistons the same size as those found in a Dodge Viper supercar, the biggest back tyre on a production bike…it’s simply an incredible experience and bravo to Triumph for making it. The engine itself is bigger than most cars on the road!

The Rocket III !

But it’s not intimidating to ride. Triumph actually softened the power delivery in the first three gears, so although acceleration is outrageous it’s never out of control. However, its still immensely powerful! I was cruising when I realised I had already hit 100mph and the engine was turning over at only 3000rpm!

It's huge!

Anyway, it was an amazing experience test riding the world's largest bike. Although it is a good bike, I feel that it doesn't really suit me. I prefer a more sportier bike and something less heavier and cumbersome. Plus it costs eleven grand! That is a lot of money for a lot of bike! Well, you get what you pay for.

It's sexy & powerful!

So, now that the weather is getting better (and warmer), I shall be doing more rides on my bike around the countryside, and will post some pics on the places that I have visited on my rides.

But not for me....

Sunday, April 01, 2007

Animal Encounters XVII

The Blue Poison Dart Frog

Poison arrow (or dart) frogs are brightly-coloured toxic amphibians in the family Dendrobatidae. Their bright colouration serves as a warning to potential predators that this frog is harmful to eat. The frogs' toxins are concentrated in its skin but these are not one of the three or four species that are thought to be dangerous to humans. They are small, rarely more than 4 cm long.

Me and my paradise!

These species live in permanently damp leaf litter on the forest floor. They are most active in mornings and evenings. Males have bright colours that they use to display with. Each male defends a small patch of the forest floor, where he will chirp and trill, while showing off his colours. If his display is good enough he will eventually attract a female into his patch.

Me & my love shack! Wanna come in?

They can breed all year round if food is plentiful, and the females will lay around six to ten eggs in a secluded area on the land or on a leaf. They are fertilised by the male, who then assumes most of the responsibility for caring for the clutch. He guards them and keeps them moist by transporting water from a pool. When the tadpoles are ready to hatch (usually three to four weeks), he allows them to wriggle onto his back and he carries them to a suitable pool of water. This may be a small pool on the forest floor or in the leaf bract of a bromeliad plant several metres off the ground. For the next month or so, the tadpoles feed on algae and dead insects in the pool until they are ready to change (or 'metamorphose').

Me and my waterfall! Wanna dive in?

They eat insects, especially ants- myrmevore. The ants supply some of the frogs' toxins. In Bristol Zoo Gardens, the frogs are fed on hatchling crickets, fruit flies and, during the summer, aphids. Poison dart (or arrow) frogs are so named because the poison from their skins is taken by Colombian Indians to smear onto the tips of their blow-pipe darts and arrows to help kill animals when hunting. In fact, only a very few species are used for this purpose, but this common name has been applied to their close relatives. Unfortunately, the blue poison dart frog is at risk in the wild due to habitat loss. This species is on a European breeding programme.

Unlike last year, this is not an April Fool's joke. They really do exist.