Where the wild things are

Pierson Hill shares his photos of some of Trinidad’s rarest and most fascinating creatures

Bird-eating snake. Photograph by Pierson HillDragonfly. Photograph by Pierson HillFer-de-lance. Photograph by Pierson HillGladiator tree frogs. Photograph by Pierson HillGuppy. Photograph by Pierson HillLiana snake. Photograph by Pierson HillLora or parrot snake. Photograph by Pierson HillSouth American wood turtle. Photograph by Pierson HillTurnip-tail gecko. Photograph by Pierson HillWall lizard. Photograph by Pierson Hill

Growing up in north Florida, Pierson Hill developed a passion for the outdoors and living things – with a special emphasis on the slithery, slippery, crawling creatures that most people dislike or would prefer to ignore. Currently studying for a PhD in ecology and evolutionary biology at Florida State University, he combines his love of photography with his biological research work – not an easy task, owing to the logistics of the kind of research he does. He’s determined to catalogue all of the species he is lucky enough to come into contact with.

Hill comes to Trinidad for a few weeks at a time to work on the Guppy FIBR project (see below). During that time he works in the Northern Range, assisting with the marking and recapturing of the Hart’s rivulus or “jumping guabine” (Rivulus hartii), which is the only other fish that lives with guppies at high elevations. Because Rivulus are most active at night, that is when the research is done, allowing Hill to digitally capture many nocturnal animals that most of us would have little or no chance of seeing if we ventured into those areas during the day.

You can see more of Pierson Hill’s photography online at www.flickr.com/photos/nclarkii

As pretty as it is strange, the liana snake (Siphlophis compressus) hunts low vegetation at night for lizards. They are considered rare in Trinidad, but Hill has had the good luck to see this species on several occasions in the streams of the upper Guanapo Valley

On dry nights, male gladiator tree frogs (Hypsiboas boans) descend from the treetops and signal to females with a repeated, “Werrk, werrk, werrk”. The pair will dig and lay eggs in a shallow bowl-like nest in soft sediment at the edge of a stream. Gladiator tree frogs are one of the largest species of tree frog on the planet, with females nearing the size of an open hand. Because of their weight, moving among small branches and vines can be awkward

Turnip-tail geckos (Thecadactylus rapicauda) are excellent for pest control. They patrol walls and ceilings at night, snacking on roaches and spiders

Fer-de-lances (aka mapipire balsain, Bothrops asper) are feared and loathed across Trinidad. They are certainly venomous and can deliver life-threatening bites, but their villainous reputation is much exaggerated! The Trinidad variety seems to be far more easy-going than its Central American brothers. This baby fer-de-lance uses its yellow tail-tip as a lure to attract small frogs and lizards

The South American wood turtle lives in shallow streams and swamps in Trinidad’s lowland forests. It’s a small species that eats a variety of aquatic insects, snails, and fish. This species will readily travel over land during dry periods and to lay eggs – which puts it at risk of being killed by vehicles

The lora or parrot snake (Leptophis ahaetulla) cruises the edges of forests and low trees for lizards and frogs. Although not dangerous to humans, this species has large rear teeth, which it uses to deliver a mild venom into its prey. This snake was photographed in the narrow gorges of the upper Guanapo River

Wall lizards (Tropidurus plica) inhabit large tree trunks and rural buildings in Trinidad’s rainforests, and are active during the day. They rely on their coloration to remain unseen by predators, but have impressive speed when their camouflage fails them. This individual lived on the walls of Simla, a biological research station in the Northern Range’s Arima Valley

Trinidad has an impressive array of colourful dragonflies. Small, stagnant ponds often harbour quite a variety of these efficient mosquito-eaters. A patient photographer can snap a quick photo as they briefly perch on low bushes

Bird-eating snakes are a common, harmless species around rural settlements, as they seem to like forest edges, where rats and nesting birds abound. They put on an impressive display when threatened – inflating their necks, gaping, and biting – but their small teeth and weak jaws can’t do much damage

 

A good look at guppies

The Guppy FIBR project is a five-year study of the dynamic interplay between evolution and ecology, centred in the mountain streams of Trinidad’s Northern Range. FIBR stands for Frontiers in Integrative Biological Research, a programme run by the US National Science Foundation.

Their website explains that the Trinidadian guppy (Poecilia reticulata) is an excellent species for the purposes of the study because it matures rapidly (one generation is three to four months), and it inhabits different ecological environments that can be easily manipulated.

Researchers are tracking experimentally introduced populations of the guppy as natural selection pushes them between a high-predation lifestyle (which leads to fish with drab coloration, which produce lots of small babies) and a low-predation lifestyle (colourful, with a few, big babies).

During this process, other teams of researchers monitor the resulting effects on other facets of the ecosystems of the streams. The results of this groundbreaking work will provide an initial look at how an evolving population can actually affect the environment in which it is evolving.

For more information visit http://cnas.ucr.edu/guppy