Estrilda astrild - is the only introduced bird of the isle. It is one species of Passeres from Reunion Island and it was brought in to Amsterdam in 1977. A hundred or so of these birds nest in the vicinity of the base on the Isle of Amsterdam.

All the mammals introduced on the isle are terrestrial ones.

Those surviving on the island are as follows:

Mice - Mus musculus - They seem to have adopted an exclusively vegeterian diet.

Rats - Rattus norvegicus - They eat eggs and chicks in summer but adopt a vegeterian diet in winter.

Cats - Felis catus - They mainly feed on birds, mice and rats. Some of them can regularly be watched on the base and are sometimes fed by the staff.

Cattle - Bos taurus - They are descended from the five animals left by Heurtin after his stay on the isle in 1871. The herd has turned wild now. There were between 1,000 and 1,500 of them in 1983 and more than 2,000 in 1987.

 Many consequences over the island flora and fauna have resulted from the presence of this cattle for more than a century.

As far as the flora is concerned, the confining of the Phylicas in inaccessible areas to the cattle suggests that they exert an improtant predation on the trees. Moreover the soil of the grazing zone is so highly damaged that rock shows on the surface at places.

Antonelli Crater is located in the grazing zone.

Some Phylicas are naturally sheltered from the cattle there.

 

Close to Antonelli Crater, the only remainning Phylica is a relic from the big belt. It is a rather tall tree - 5 to 6 metres high - but protected from the cattle by barbed-wire.

As for the fauna, the numerous sub-fossil deposits of bones of Amsterdam albatrosses - found in the present grazing zone - suggests that the disturbances caused by cattle (treading of lived-in areas, nests, etc.) has compelled the albatross to confine higher up to the "Plateau des Tourbieres", which is less accessible to the cattle.

A rehabilitation program of Amsterdam Island has been started since 1987.