Thirteen species of freshwater fish have been recorded in Tobago, but only a handful of these have successfully conquered the Main Ridge. While we humans can easily drive along the Roxborough – Parlatuvier road to access the reserve, fish must initially colonise inland from the sea. In North East Tobago, fish in the lower reaches moving upstream soon reach one of many waterfall barriers at the edge of the Ridge. Often these are tens of metres high, much like those at Argyll. Most fish will never manage to traverse these barriers, forever restricted to the lowland rivers. Only the most intrepid make it through to dominate the uplands. Without a doubt, the king of the Main Ridge rivers is the Jumping Guabine, Aneblepsoides hartii. Ordinarily, this species reaches around 10cm from head to tail. However, the Main Ridge individuals are decidedly larger, as with fewer fish predators they can live longer. |
This piece originally appeared in the Tobago Newsday on March 16th 2017.
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Trinidad & Tobago’s rivers are filled with at more than 40 different species of fish of all shapes, sizes and habits. One of the best-known is the ‘teta’, also called the ‘Anne Marie’, and known to scientists as Hypostomus robinii.
This article originally appeared in the Newsday as part of the TTFNC's natural history series. The rivers of Trinidad are home to six very distinctive types of catfish. These include armoured catfish such as the leopard-spotted ‘teta’ (Hypostomus robinii), the enigmatic ‘cascadu’ (Hoplosternum littorale) and the popular aquarium fish ‘pui pui’ (Corydoras aeneus). All tend to be bottom-dwellers and are grouped together as ‘cat’ fish on account of their barbels, which are sensory ‘whisker-like’ structures on their faces used to locate food. In Trinidad the fish most commonly referred to by the name ‘catfish’ is Rhamdia quelen, which unlike the species listed above, is silvery, unarmoured and scale-less. Rhamdia is found throughout much of Central and South America, from Mexico to Argentina. In T&T, it is especially common in the rivers of the southern slopes of the Northern Range, but is found throughout the country, with the exception of Trinidad’s north coast and the whole of Tobago. Like many catfish species, Rhamdia possess mildly venomous spiny rays on their pectoral and dorsal fins, which are used for defence against larger predatory fish. The barbels on either side of their face help them locate food in dark or murky waters, such as their preferred prey of small fish. However, their varied omnivorous diet also includes insects, zooplankton, plant matter and crustaceans. Despite living in Trinidad for over 4 years now, there are still some hikes that I have yet to try, so I was excited when a friend suggested we attempt a new route in the north of the island – to the elusive St Cion Bay. We began in cool, breezy hills at the western end of the Northern Range – near the village of Paramin, a farming community famous for music, blue devils and cool breezes. Unfortunately the view from the ridge was non-existent as we were greeted by sheets of rain, even though March is traditionally one of the driest months here. This also meant that the downward hike was treacherous, with slippery rocks and leaves underfoot. We were forced to take a very slow pace, watching our every step – and even so, several of our party ended up on the ground at various points. Thankfully no serious injuries were sustained, and the forest in the misty rain was magical. This feature originally appeared as part of the TTFNC's weekly natural history series in the national 'Newsday' paper. If you are lucky enough to have spent any time as a child catching fish in ditches and streams, you have almost certainly encountered this particular species. It is known by several names, including the formal scientific name of Anablepsoides hartii (formerly Rivulus hartii), Hart’s rivulus, and ‘seven colours’. However, most people probably know it as the ‘jumping guabine’. At full size, these small fish are around 10cm and although dull from a distance, they have vivid horizontal coloured stripes stretching along their body. Males and females can be distinguished fairly easily by their colouration; males tend to be brighter and have distinctive pale orange edges to the tail, while the female’s tail has a darkened tip (see photo below). Jumping guabines are found throughout T&T as well as in northern Venezuela. They thrive in a variety of habitats, from muddy road-side puddles to the shallow edges of large rivers. We are now entering the final year of the 5-year biodiversity project out here in Trinidad. To mark this milestone, I have begun writing a blog for the BioTIME website, which will be updated regularly to document fieldwork adventures over these last months. I hope to offer insights into what it's like doing fieldwork here on a day-to-day basis, and from time to time it will also feature species' profiles of some of the most interesting inhabitants of the Northern Range streams... You can visit the blog here. It's all very well being told not to eat popular seafood such as shark and shrimp - but what are the alternatives? In the UK and USA there are already comprehensive guides to help people choose more sustainable options when dining on seafood. In this guide, published in the Caribbean Beat magazine last month, Robin Ramdeen (of Papa Bois Conservation) and I set out to provide Caribbean consumers with the information they need to make informed and more sustainable choices... We all know that fish is an excellent source of lean protein, and some species provide us with a healthy dose of fish oils and vitamins. That’s why we’ve been eating seafood for aeons. But times have changed, and so have the oceans. The sad reality today is that not all our seafood choices are harmless. Many species are in trouble due to over-fishing, and are now endangered globally. Plus, many commercial fishing methods are destructive to marine habitats. For instance, shrimp trawling is one of the most damaging and wasteful fishing methods ever invented. As a result, trawler-caught shrimp isn’t a wise choice for any ocean-lover. Further, there’s your health to consider: many large-bodied fish like shark, tuna, marlin, and swordfish can contain harmful contaminants such as mercury. In case you didn’t already know, if it accumulates in large enough quantities, mercury can negatively affect brain development and the nervous system. So the next time you’re dining at your favourite restaurant, think twice before ordering that mouth-watering basket of succulent shrimp, or that delicious bake and shark. Your thought process should go something like this: 1. Is it okay to eat this (in terms of population sustainability and human health)? 2. Is the method used to catch this okay for the environment? This article was written by Amy Deacon and Kris Sookdeo, and originally appeared in the TTFNC's Newsday column. Ask any Trinidadian what a zangee is and you are likely to get a range of responses. Some will tell you it is a “swamp eel,” others insist on calling it a “water snake.” More still will reveal that they are not sure what a zangee is exactly, but they are terrified of them nonetheless; perhaps they have heard the rumours about this mysterious creature, which is said to suck on your toes should you happen to tread barefooted into the water. The truth is that the zangee, more formally known as Synbranchus marmoratus, is actually a type of fish. With their slippery, elongated body (up to 1.5 metres long), the confusion is completely understandable. Adding to the mystery is the fact that they lack well developed fins and their bodies are essentially scaleless. Indeed, it is surprising to discover that they are not closely related to the true eels at all (which may also be found occasionally in Trinidadian waters), and their resemblance to a snake is entirely superficial. Sometimes spelt janjii or zangie, the origin of the name is actually “les anguilles” which is French for eel. Like many local French-derived names that begin with the letter “a,” Trinidadians added a “z” and, over time, the word morphed into the zangee that we know today. Outside of Trinidad, the zangee is found throughout Mexico, Central and South America and on a few islands of the Caribbean. Within T&T, it is one of the most widespread fish in the islands’ waterways, inhabiting a wide range of habitats from muddy swamps and drainage ditches to clear, pristine mountain streams. It is primarily found on the southern slopes of the Northern Range, but has on occasion been found along the north coast at Sans Souci and Yarra. Shark conservation is a hot topic here in T&T at the moment. I have written a piece on the campaign for my research group's website. You can read it here or below. I never turn down a chance to promote my favourite fish, so when the Trinidad and Tobago Field Naturalists’ Club invited me to contribute to their new weekly column in the local newspaper, I accepted immediately! The print version was accompanied by some colourful photos, but you can read the article itself here. Other contributions have included a piece I co-authored on two of Trinidad’s most charismatic garden birds, and a lovely column by another club member about the beautiful immortelle trees that brighten up the forests here during dry season. |
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