As I begin my expedition on Fernando de Noronha it becomes increasingly clear how the biological history of the island and the introduced species I am here to study are tightly intertwined with the human history of the island.
Fernando de Noronha is an oceanic island of volcanic origin, never connected to any continent, nor inhabited by people.
It was first discovered in 1503 by Amerigo Vespucci who noted in a letter home the presence of “very large rats.” On a National Geographic grant in 1973, Smithsonian curator Storrs Olson confirmed the fossil presence of such a giant rat which he named Vespucci’s rat (Noronhomys vespuccii), and which went extinct rapidly following human colonization.
The island subsequently passed hands between the Dutch and French and finally back to the Portuguese where it remained until Brazil’s independence. Remains of forts from throughout this era are found across the island.
For much of its history the island was a dreaded penal colony, and it was at this time that the forest across the entire island was regularly burnt off. The plants present today include a mix of regenerating natives but also invasive plants such as Leucaena leucocephala and Lantana camara.
The first proper biological studies were not conducted until much later in the late 19th century by Brammer (1876) and Ridley (1887). By this time the presence of cats, mice, and non-native rats, and the decline in seabirds, were all noted.
In the early 20th century the island became the base of a Brazilian military garrison and the U.S. military were briefly stationed here from 1942-1945, at which time they built much of the modern infrastructure including the current runway and hangars.
It wasn’t until the 1960s that tegu lizards and mocó rodents, which we are here to study, were introduced to the island.
In 1988 governance of the island was devolved to Pernambuco state and the island was divided into 70 percent national marine park and 30 percent environmental protection area, the latter allowing habitation and sustainable development along with tourism. In 2001 the archipelago was given UNESCO World Heritage status.
Today the population is around 2000 residents, 300 semi-resident workers, and a maximum of 1000 tourists at any one time, effectively limited by the number of daily flights and a tourist tax. All these people tenuously co-exist with the introduced and native species on the island which I am here to investigate.