Fossil vertebrates from Antigua, Lesser Antilles: Evidence for late Holocene human-caused extinctions in the West Indies

Abstract

Vertebrate remains recovered from a limestone fissure filling on Antigua, Lesser Antilles, are associated with radiocarbon dates ranging from 4300 to 2500 yr B.P., contemporaneous with the earliest aboriginal human occupation of the island. Nine taxa of lizards, snakes, birds, bats, and rodents (one-third of the total number of species represented as fossils) are either completely extinct or have never been recorded historically from Antigua. These extinctions came long after any major climatic changes of the Pleistocene and are best attributed to human-caused environmental degradation in the past 3500 yr. Such unnatural influences have probably altered patterns of distribution and species diversity throughout the West Indies, thus rendering unreliable the data traditionally used in ecological and biogeographic studies that consider only the historically known fauna.

A new fossil species ofBoaLinnaeus, 1758 (Squamata, Boidae), from the Pleistocene of Marie-Galante Island (French West Indies)

“…The extinction of Boa is thus likely to be linked to a natural phenomenon. However, on account of the lack of data beyond Marie-Galante for the first half of the Holocene and the still elusive Amerindian preceramic populations (Siegel et al, 2015), the first human communities colonizing the Guadeloupe islands, we cannot rule out the role of human populations in some of these putative extinctions, as seems to have been the case on Antigua (Steadman et al, 1984;Pregill et al, 1994). The discovery of more fossil evidence of the past occurrence of Boa in the Guadeloupe islands is thus required to provide solid ground for its past occurrence and the timing and reasons of its extinction on all the Guadeloupe islands.…”

“…This hypothesis is partly confirmed by historical evidence demonstrating the past occurrence of Boa snakes on the islands of Martinique (Labat, 1724;Breuil, 2009) and Saint Vincent (Moreau de Jonn es, 1816), showing that these large snakes probably became extinct recently: during the 18th century on Martinique and during the 19th or 20th centuries on Saint Vincent. In addition, fossil evidence suggests the past occurrence of Boa snakes north of Dominica, as far as the northernmost island of Antigua, during the Holocene (Steadman et al, 1984;Pregill et al, 1988), but also on Marie-Galante Island during the Pleistocene (Stouvenot et al, 2014;Bailon et al, 2015;Bochaton et al, 2015b). This fossil evidence indicates that Boa may also have been present on all the Lesser Antillean islands separating Dominica from Antigua, including the Guadeloupe islands.…”

Living and late Holocene fossil vertebrates, and the vegetation of the cockpit country, Jamaica

“…), the extirpated Burrowing Owl (Athene cunicularia), and the extinct night jar Siphonorhis americana (Olson andSteadman, 1977, 1979). Only ten avian fossils were recovered from Marta Tick Cave.…”

Faunal Turnover in South American Fossil Avifaunas: The Insufficiencies of the Fossil Record

“…We now know that it is not even possible to reconstruct Holocene avifaunas based on "Recent" birds (Olson andJames, 1982a. 1982b;Steadman et al, 1984). The second conclusion is founded on data that are, in my opinion, too inaccurate to permit any such generalizations to be made.…”