Lemurs in Madagascar: Surviving on an Island of Change Transcript
Transcript Speakers: Ian Tattersall, Jonah Ratsimbazafy, Michelle Sauther, Frank Cuozzo (Rain trickling, lemur sounds: squeaking and calling) (Music playing in background)
IAN TATTERSALL: I think everybody who is involved with lemurs is concerned for the future. We’re in a finite island that cannot infinitely be exploited and ravaged. And if present trends continue, the outlook for any of the natural habitat or any of the lemurs is fairly poor. (Birds chirping) Lemurs are members of the order primates, that is to say the large group of mammals to which human beings also belong.
And they’d found they are uniquely in Madagascar and on a couple of the adjacent islands of the Comoros group. (Music playing in background) An evolutionary radiation is the diversification of different species from the same ancestor and once a new kind of organism like a primate comes into a new environment as happened in Madagascar about sixty million years ago; there are many, many different ways in which that environment can be exploited. It’s very hard to say exactly how many species of lemur there are because new species are being described all of the time.
But in general terms, there now looks to be about thirty to thirty-five species of lemurs and it shows us just what the potential of primates is to occupy an enormous range of different habitats. (Music playing in background) Habitat destruction takes place on a much shorter time scale than evolutionary change and the amount of change that is happening so rapidly in Madagascar as a result of human activities is clearly something with which no evolutionary process can cope.
JONAH RATSIMBAZAFY: Now we are here in Ranomafana National Park in the southeastern rainforest of Madagascar.
This place used to be loved by loggers but since the park was created, the forest started to be productive. Here in Ranomafana, there are twelve different species of lemurs. Seven are active during the day and five are active during the night. There are many different ways of studying lemurs. It depends on what you want to look at. (Speaking in background) I look at the behavior and how the behavior fits in the habitat. For example, if you want to know which foot and what prints they rely on because if we can continue to protect the habitat, that will help to protect them or to conserve them.
Every five minutes we take note what species of tree, who the closest neighbor is, the closest trail, because we want to know where do they go to estimate the home range and if they eat, what do they eat. Some species cope better than the others. If you are a specialist on your diet and if people cut down your food, you are gone. For example, the bamboo lemur. They exclusively eat bamboo and if people cut down those plants, they are gone. They can disappear very fast. (Music playing in background)
IAN TATTERSALL: Different lemurs are affected in different ways by the environmental destruction that is going on in Madagascar.
Some lemurs are in danger, some are critically endangered, some are vulnerable, and some are threatened. The less vulnerable ones are the ones that do well in secondary habitats, in habitats that have been altered by people.
MICHELLE SAUTHER: We’re at a site called Beza Mahafaly, and it incorporates a protective reserve as well as areas outside of the reserve and our research here focuses on the effects of fragmentation and changes in habitat on lemur biology and their behavior. We study lemur catta which is the ring-tailed lemur. It’s the type of lemur most people have seen in zoos.
They are one of the most far ranging of the lemurs. They are incredibly adaptable and one of the things that we are kind of interested in is what is the biology of adaptation or what is the biology of avoiding becoming extinct. And because ring-tailed lemurs are so widespread, and that’s not to say they’re not threatened, but they seem to be able to deal a lot behaviorally and biologically with habitat change. I think what we’re seeing in terms of the troops we were looking at today is a troop that is actually utilizing some of the anthropogenic change.
They will go out and utilize local people’s crops so they are actually exploiting some of the habitat that has been degraded and turned into crop land for their own use.
FRANK CUOZZO: In terms of the ring-tailed lemurs, because they are rather generalist, they do seem to adjust to different types of disturbance. As Michelle mentioned a few moments ago, it doesn’t mean that we don’t have to watch out or think about it and it doesn’t mean there aren’t very real threats to long-term survival, but ring-tails specifically seem to deal with things in ways that some of the more specialized lemurs don’t.
MICHELLE SAUTHER: But there is always limitations to those though. That’s what we’re trying to understand is where are you when you get to the limits of even a ring-tailed lemur in terms of being able to adapt. (Music playing in background) I used to feel depressed when I came here because, again, you see the habitat changing and a lot of fragmentation occurring. I feel a bit better now because we’re trying to really get a handle on what sort of ways you can interact with local people because that is the reality.
What you saw around here is the reality of Madagascar.
IAN TATTERSAL: I think what we ought to be looking for in terms of conservation is habitats to protect and what we need to do is to find those places where, with the least disturbance to local people or to the greatest benefit of local people, tracks of forest that support the native fauna of Madagascar can be conserved. (Lemur sound) [End of Audio]
