Porto Santo rabbit

According to the zoologist Carlos França, the Porto Santo (‘holy harbour’) rabbit has the characteristics and appearance of the common wild rabbit of southern Europe, differing from it only in the shape and dimensions of the skull. For this zoologist, the rabbit – of which Haeckel gave a description as fanciful as it was inaccurate in his Historia da Criação Natural – is a subspecies of Oryctolagus cuniculus, O. cuniculus Huxleyi, peculiar to Porto Santo and impossible to distinguish by its external characteristics from the meridionalis form of the European rabbit.

Darwin, who had the opportunity to examine and study seven Porto Santo rabbits, two of them alive, noted that they differed from the common English rabbit in both colour and size. It was perhaps this circumstance that led Haeckel to create his Lepus Huxleyi, to which he attributed ‘a particular colour, a shape approaching that of the rat, nocturnal habits and an extraordinary wildness’.

It is not only in the colour of their fur that the Porto Santo rabbits are identical to those of the Mediterranean region; they are also identical in other easily observed external characteristics. For Miller, the rabbits of that region, those of the Madeira archipelago and those of the Azores form a single subspecies – the subspecies Haxleyi – a view we would have no hesitation in accepting, were it not for the osteological differences pointed out by Carlos França.

The Porto Santo rabbit is, as a rule, somewhat smaller than the rabbit of other countries. This may perhaps be attributed to lack of space, as Professor Delage says: that is, to the difficulty that species confined within certain limits have in strengthening their stock through crossing between varied and numerous individuals.

Professor Camilo Torrend says that on Porto Santo rabbits, like cattle and certain molluscs, present typical examples of dwarfism. We may add that certain plant species, such as mistletoe, the wild olive, cliff box (buxo da rocha), etc., also reach smaller dimensions on that island than on Madeira, owing to environmental influences.

Crosses between Porto Santo rabbits and European ones are not only possible but are in use as a means of strengthening and restoring the stock. As for wild habits, it seems to us that there is no reason to attribute them solely to the animals of that island. The rabbits of Madeira are just as shy and untameable as those of Porto Santo when caught after a certain age.

Azurara relates that a friend of Bartolomeu Perestrelo, the first donatary of Porto Santo, had given him a doe rabbit which bore young during the voyage. On reaching the island, Perestrelo released the mother and her litter, but within a short time these animals multiplied so greatly that nothing could be sown or planted without being at once devoured or spoiled by them. The first settlers tried in vain to wipe out the rabbits; the animals survived everything, so that the new colony had to be abandoned, since it brought nothing but losses to those who were settling it.

João de Barros, Gaspar Frutuoso, António Cordeiro and Cadamosto tell the story of the doe brought by Bartolomeu Perestrelo in almost identical terms, and it is from this doe, beyond dispute, that the present-day rabbits of Porto Santo descend.

In our view, the creation of the subspecies huxleyi by the Portuguese zoologist Carlos França is fully justified by the cranial characters of the animals it includes. External characters are of little importance in the case in question, all the more so as it is known that the two rabbits examined by Darwin acquired, within very few years and under the influence of new climatic conditions, the colour of the common English rabbit. The internal characters already noted, however, cannot be lightly dismissed, for they represent profound modifications undergone by the species.

The distinctive build of the Porto Santo rabbit seems, says Carlos França, to accord with the animal’s conditions of life. Living on a very small island with rather sparse vegetation, the rabbit could not thrive without well-developed sense organs, and its skull consequently underwent marked modifications, such as to characterise the subspecies huxleyi.

We set out below the characters that Dr Carlos França found in the four specimens on which he based his study of the Porto Santo rabbit:

“

Back chestnut, nape reddish, belly light grey in three specimens and dull grey in the fourth. The upper side of the tail is leaden grey, with a few rare hairs with yellowish tips; the hairs on the underside of the tail are white. The ears do not have darker tips, and the chest region is light chestnut...

The length of the four Porto Santo rabbits kept in captivity, measured from the incisors to the anus, was 32, 35.5, 36 and 37 centimetres respectively, that is, 35.5 centimetres on average. The smallest of all these rabbits was a male, which was rather poorly nourished.

The weight of these specimens, three of which were fat, was 815, 755, 745 and 650 grams, that is, an average weight of 741 grams’.

Although Haeckel visited Madeira in 1866, he neither saw nor studied the Porto Santo rabbit, and almost everything he says about this rodent is pure fantasy. It would indeed be curious if an animal carried to a small island had changed there within the space of 4 or 5 centuries to the point of producing a new species. Such facts, and others like them, are recorded only by naturalists of little seriousness, or by those who study superficially certain complex biological problems that deserve the most careful consideration.

Bibliography