No longer the rarest snake

Antiguan racers are endemic to the twin-island country of Antigua and Barbuda. Following the introduction of invasive mammals (rats and mongooses) in the 1800s, the species suffered a drastic decline and, by 1995, only around 50 of these snakes survived on just one offshore islet.

Happily, following work by Fauna & Flora International and partners to eradicate the alien species and reintroduce the snakes onto other offshore islands cleared of invasive predators, the population and range of the Antiguan racer has increased to over 1,100 individuals spread across four separate sites.

Antiguan racer facts

  • Not so fast! Despite their name, these racers are actually rather slow. They prey on four endemic species of lizard, which they catch by waiting in ambush.
  • The Antiguan racer is one of very few snakes in which males can be distinguished from females by their colour. Their colouration also changes dramatically with age.
  • These placid snakes are harmless to humans – their only defence is to emit a musky smell when frightened.
  • The Antiguan racer has incorrectly been declared extinct twice: the first time in 1936, and again in 2009.
  • Most of the Antiguan racers alive today have been implanted with microchip tags for security purposes and to monitor their growth and survival.
At a glance
Alsophis antiguae
Critically Endangered Critically Endangered
Antigua and Barbuda Antigua and Barbuda





Est. in the wild:

Over 1,100


Once so rare it was believed extinct, the Antiguan racer has rebounded as part of a stunning conservation success story.


FFI and partners first began work to save the Antiguan racer.

x 22

Antiguan racer numbers have increased 22-fold since 1995.

Conservation story

Dubbed the ‘world’s rarest snake’ in 1995, when only 50 individuals remained, the Antiguan racer has been making a steady comeback with help from Fauna & Flora International (FFI).

Antiguan racers used to be the top predators throughout Antigua and Barbuda until small Asian mongooses were introduced in the 1890s to control invasive black rats that were damaging European plantation sugar cane crops. The mongooses had little impact on the rats, and preyed on native species instead, wiping out most Antiguan racers. The species was declared extinct in the 1930s, but a few survived on Great Bird Island, an 8.4-hectare cay that had luckily remained mongoose free.

In partnership with other national and international organisations, FFI helped to eradicate the rats and other harmful invasive alien species from Great Bird Island and a further 14 islands around Antigua, before reintroducing  Antiguan racers to three of these: Rabbit, Green and York islands. Today, the population in the wild exceeds 1,100 individuals, a 22-fold increase since conservation efforts began.

Many other species have also benefited from this work, not least bird colonies on islands cleared of invasive predators – some of which have increased more than 30-fold! Species that have begun to thrive again include many regional rarities, such as the West Indian whistling duck and Caribbean brown pelican.

Although good progress has been made, the Antiguan racer and its habitat remain at constant risk, due to the rising numbers of visitors to the offshore islands where it lives, as well as the chronic threat from alien invasive species and coastal development.

Snakes are often difficult to conserve due to negative public perceptions, but through education campaigns and awareness-raising the Antiguan racer has become an unusual flagship species for conservation in Antigua and Barbuda, and features prominently in the national environmental education curriculum. Many Antiguans and Barbudans have become justifiably proud of their unique snake and its unique island ecosystem.

How FFI is helping to save the Antiguan racer

FFI has been integral to the Antiguan racer’s remarkable recovery, and to this day we continue to support efforts to monitor for signs of rats reinvading the islands we have cleared.

We are also applying the lessons we have learned here across the Caribbean, and hope to replicate this success with the Saint Lucia racer, which has taken on the Antiguan racer’s unwelcome mantle as the world’s rarest snake.

“The Antiguan Racer Conservation Project began in 1995, when FFI responded to a call for help from Antiguan naturalist Kevel Lindsay. Incredibly, some conservationists advised us against intervention, because the snake was too rare and unpopular. I am so glad we have proved the doubters wrong, and helped to turn the fortunes of this unique and lovely animal.”
Dr Jenny Daltry Senior Conservation Biologist