The poster can be download at the end of the article.It was prepare for the Conférence Internationale Biodiversité : science et gouvernance, Paris 24 - 28 janvier 2001.

S. Grouard et J.-D. Vigne; MNHN USM 303 - CNRS UMR 5197; "Archéozoologie", Dept E.G.B.; CP 56, 75231 Paris; grouard@mnhn.fr et vigne@mnhn.fr.

The poster to download

Archaeozoological studies bring information on the history of the vertebrate faunas during the last 10,000 years, and on their relationships with human activities. In the islands, this information allows to study the mechanisms of the human impact on the biodiversity at the scale of centuries or decades. Here, we compare the results of two different island systems, the Caribbean and the Mediterranean.

1. Case studies: mammals of Guadeloupe and Corsica

The early Pre-Columbian and the Modern European waves of colonisation, and also perhaps the recent Pre-Columbian one, provoked introductions of mammal species. Only the last wave of human immigration provoked extinction.

• The biodiversity of the archipelago increased from 4 to 15
• All species initially present on the island got extinct
• All the present day species result from introductions due to human being, voluntarily or not:
  • domestic animals (dog, sheep, pig, cattle, horse...)
  • local populations resulting from the feralisation of the domestic species (feral cat, mangoose)
  • commensal species introduced as stowaways (mouse, rats)
  • small or large game (agouti, red brocket deer, rabbit...)
  • species with special symbolic or social value (racoon, opossum, armadillo, squirrel...)

Large native mammals get extinct because of the Holocene warming. The Mesolithic colonisation did not bring any change in the biodiversity. However, the Neolithic wave initiated a continue phenomenon of invasion. The native small mammals got extinct during historical times because of the agricultural area extension.

• The biodiversity of the island increased from 6 to 26
• All species initially present on the island got extinct
• All the present day species result from introductions due to human being:
  • domestic animals (dog, sheep, pig, cattle, horse...)
  • local populations resulting from the feralisation of the domestic species (mouflon, boar, feral cat...)
  • anthropophylous or commensal species introduced as stowaways (garden dormouse, field mouse... ; mouse, rats, weasel...)
  • small or large game (hare, rabbit, fox, red deer...)
  • species with special symbolic or social value (headgehog, feral bear).

2. Mammals: broadening to other islands

The pattern of the mammal species turnover is the same for all the studied islands.

Differences between islands are:

• the native extinct species were specific to each island
• timing of the first human impact is shifted toward more recent dates from the South to the North for the Caribbean, and from the East to the West for the Mediterranean, according to the human waves of colonisation

However, invasive species are the same inside each of the two insular systems and even between them.

Though it increased the biodiversity of each island, human being drastically decreased the global biodiversity of both the Caribbean area and the Mediterranean basin.

3. Mammals, birds, reptiles and amphibians

Back to the two case study, it appears that the impact of human beings has been much stronger for mammals than for birds, reptiles and amphibians. Only 0-5% (Corsica) to 30% (Guadeloupe) of non mammal vertebrates got extinct. In Guadeloupe, most of them lived in narrow biotope in the forests, and have been over-hunted for meat (Lesser Antilles iguana), feather (parrot) or defence (snakes). Among the non mammal invasive species, there are game (partridge) or cage birds (African waxbills, new species of parrots...), stowaways (gekkos, frogs) and open field birds which took advantage from deforestation (cattle egret in the Guadeloupe, numerous species of sparrow in Corsica).

These archaeozoological approaches must be developed in the future because they allow:

• to detect the unknown species which became historically extinct,
• to evidence the different components of the human impact, according to different kinds of societies, ecosystems and species,
• to assess the increase of present day extinctions/invasions with reference to the past.

References

 GROUARD S., 2001.- Subsistance, systèmes techniques et gestion territoriale en milieu insulaire antillais précolombien - Exploitation des vertébrés et des crustacés aux époques saladoïdes et troumassoïdes de Guadeloupe. Mém. Doc. Univ. Paris X.

 VIGNE J.-D., 1999.- The large "true" Mediterranean islands as a model for the Holocene human impact on the European vertebrate fauna ? Recent data and new reflections. In : N. Benecke éd., The Holocene history of the European vertebrate fauna. Modern aspects of research (Workshop, 6th-9th April 1998, Berlin). Berlin : Deutsches Archäologisches Institut, Eurasien-Abteilung, p. 295-322 (Archäologie in Eurasien, 6).

 VIGNE J.-D., BAILON S. et CUISIN J., 1997.- Biostratigraphy of Amphibians, Reptiles, Birds and Mammals in Corsica and the role of man in the Holocene turnover. Anthropozoologica, 25-26 : 587-604.