Reptile
Machete Couesse (Tobago)
Mastigodryas boddaerti dunni
The Tobago Machete Couesse is an endemic subspecies of Mastigodryas boddaerti found only on Tobago, where it is the island's largest non-venomous snake. Distinguished from the Trinidad nominate subspecies by differences in scalation and colouration, it fills the ecological role of an apex non-venomous predator of frogs, lizards, and small mammals on Tobago. Non-venomous and fully protected by law.
Description
Mastigodryas boddaerti dunni is the Tobago subspecies of a species whose nominate form (M. b. boddaerti) occurs on Trinidad. The Tobago subspecies was named for E. R. Dunn, an American herpetologist. It differs from the Trinidad population in details of scalation, body proportions, and colouration, reflecting millions of years of isolation on Tobago. In size and general ecology it closely parallels the Trinidad subspecies: a large, robust, fast-moving colubrid reaching up to 1.5 to 2 m.
Ecology
The Tobago Machete Couesse is an active diurnal predator, hunting frogs, lizards, small mammals, and other snakes through forest, secondary growth, and more open habitats across Tobago. As the most widely distributed large non-venomous snake on the island (there are no pit vipers or bushmasters on Tobago), it plays a measurable role in regulating prey populations. When threatened it exhibits the same defensive behaviour as the Trinidad subspecies: tail vibration, neck flattening, and vigorous striking, which is alarming but not dangerous.
Conservation
As an endemic subspecies of Tobago, any extinction of M. b. dunni would be a permanent genetic loss that could not be remedied by translocation from Trinidad, as the two populations are subspecifically distinct. The conservation of Tobago's forest habitats is therefore directly linked to the survival of this subspecies. It is fully protected under the Conservation of Wildlife Act.
Threats
- Persecution and road kills
- Habitat loss and forest clearance in Tobago
- Small island range; inherently vulnerable to stochastic events