Refine
Year of publication
- 2014 (2) (remove)
Document Type
- Article (2) (remove)
Language
- English (2)
Has Fulltext
- yes (2)
Is part of the Bibliography
- no (2)
Keywords
- invasive alien species (2) (remove)
The mature palm forest of the Vallée de Mai, a UNESCO World Heritage Site, on the Seychelles island of Praslin, is a unique ecosystem containing many endemic species, including the iconic coco de mer palm Lodoicea maldivica. In 2009, the invasive yellow crazy ant Anoplolepis gracilipes was recorded for the first time within the palm forest, raising concern about its potential impacts on the endemic fauna. This research aimed to: (1) assess the current distribution and spread of A. gracilipes within the palm forest; (2) identify environmental variables that are linked to A. gracilipes distribution; and (3) compare endemic species richness and abundance in A. gracilipes invaded and uninvaded areas. Anoplolepis gracilipes was confined to the north-east of the site and remained almost stationary between April 2010 and December 2012, with isolated outbreaks into the forest. Infested areas had significantly higher temperature and humidity and lower canopy cover. Abundance and species richness of the endemic arboreal fauna were lower in the A. gracilipes invaded area. Molluscs were absent from the invaded area. The current restricted distribution of A. gracilipes in this ecosystem, combined with lower abundance of endemic fauna in the invaded area, highlight the need for further research to assess control measures and the possible role of biotic resistance to the invasion of the palm forest by A. gracilipes.
The historical account of Aztec Emperor Auitztol's introduction of the great-tailed grackle Quiscalus mexicanus into the Valley of Mexico (1486–1502) is significant because it documents human translocation of wild birds in Mexico over 500 years ago, before the Spanish Conquest of that land. In the present paper, which defends the account from writings that dispute it, I first review the evidence of how the account was obtained and show that its many details are consistent with what is known from other sources about both the great-tailed grackle and the Aztecs (Nahuas). I then review and examine all published criticisms of the account and explain in detail why they are wrong. The critics have to date presented no persuasive evidence to support their speculation that the Aztecs confused, or might have confused, a natural invasion for an introduction. In contrast to these critics, Bernardino de Sahagún’s research group in the 1500s presented a highly credible, peer-reviewed historical account that documented Aztec introduction of the great-tailed grackle. The pioneering work of these Renaissance Mexican scholars continues to stand as one of the most important records of invasive alien species introduction in ancient times.