Two Azores shipwrecks and insect biological invasions during the Age of Discovery

Abstract

Insect faunas from a Spanish and a Dutch shipwreck, Angra D and Angra C, recovered from a bay on Terceira island, Angra do Heroísmo, in the Azores, and dated to c. 1650 CE, provide information about the onboard ecology of seventeenth century shipping vessels and the role of these ships and of contemporary maritime routes in biological invasions. In addition to evidence for foul conditions, there is evidence for similar insect faunas on both these ships. The assemblages include the earliest records of the now cosmopolitan synanthropic scuttle fly Dohrniphora cornuta (Bigot) which was probably introduced through trade from southeast Asia to Europe. The presence of the American cockroach, Periplaneta americana (L.) from Angra D, in the context of other sixteenth and seventeenth century records from shipwrecks, gives information about its spread to North America and Europe through transatlantic and transpacific trade, hitching a ride with traded commodities. The insect data point to the importance of introduced taxa on traded commodities and ballast, transported from port to port, and the role of ports of call like Angra in the Azores, as hot spots for biological invasions.