Tabla de contenidos para November 2022 en Practical Reptile Keeping

Aldabra giant tortoises (Aldabrachelys gigantea) can live for more than 100 years and weigh up to 250kg (550lb), making them one of only two gigantic members of this group alive today. Researchers at the University of Zurich (UZH) in Switzerland have now decoded their genetic blueprint or genome and their findings should now help to ensure the long-term survival of the species, which is under threat of extinction. The only surviving animals in the wild can be found on the Aldabra Atoll, northwest of Madagascar in the Indian Ocean. Thanks to their central role in the island ecosystems, these tortoises have been successfully used in rewilding projects on several Western Indian Ocean islands whose endemic giant tortoise species are now extinct. In other words, Aldabra giant tortoises act as ecosystem…

A team of researchers from NYU Abu Dhabi (NYUAD) have discovered new insights into the evolution of colour patterns in frogs and toads – collectively known as anurans. Their colour patterns can serve to provide camouflage, helping them to blend in with their surroundings and avoid detection from predators. The advantage of a stripe Many anurans have a light stripe running down their back, which, when observed from above, creates the optical illusion that the animal is split in two halves and confuses visuallyoriented predators. Although this colour pattern is widespread in frogs around the world, little is known about its evolution or genetic origins. The researchers of the Evolutionary Genomics Lab at NYUAD have now completed a broad-scale comparative analysis, which included examining over 2,700 species of anurans, to…

FEATURE | RIBBON SNAKES MY REASON for mentioning this is because when I was a kid, one of the most popular snakes you would always see in any shop that sold reptiles was the ribbon snake (Thamnophis sauritus). This was long before all of today's ball python morphs, in their dazzling array of colours and patterns. Ribbon snakes were inexpensive and proved very hardy, providing a great introduction to snake-keeping, as long as that you appreciated their rather specific dietary needs. Sadly, in an era before reptile care guides and the Internet, not everyone did, and deaths from thiaminase poisoning were the consequence. Many types of fish contain the enzyme called thiaminase, which breaks down vitamin B1 (or thiamine) in the body of animals preying on them. As a result,…

I suspect that most houses and other buildings here in Botswana, unbeknown to their owners, have at least one or more resident geckos. Apart from the small droppings they may leave here and there, you hardly ever see these useful little lizards, which provide a valuable service in keeping insects in check. I know that I would sooner have a few geckos running around, rather than cockroaches and crickets crawling about all over the place. But it is strange how many local people perceive these useful little lizards. My wife for example has a fit when she sees one! I have no idea where the belief arose, but it's widely thought that not only will geckos bite, but they are actually dangerous, although this could not be further from the…

FEATURE | COMMUNITY HABITATS While I agree that community set-ups are not suitable for everyone and that they are often destined to fail though mis-information and an incorrect understanding of what is required, I want to demonstrate that it is possible to keep vivarium occupants very successfully in this way, if you are willing to put in the work. I think that community habitats, when designed correctly, can provide enrichment both for the animals and their keeper, being a joy to own and maintain. I guess that a majority of keepers have actually thought about the appeal of setting up a community habitat at some stage. Some people may act on their ideas and set one up with lots of research, thought and experience. Others may simply wish to keep…

Greeting the gooseberry wife An amusing piece of folklore peculiar to the Isle of Wight (IOW) is that this southern English island is home to a reclusive serpentine mystery beast said to resemble a giant hairy caterpillar. It is known as the gooseberry wife, because it supposedly lurks amid gooseberry bushes waiting to devour any naughty children who try to steal the berries! Remarkably, however, there are a few reports on file from beyond this isle's boundaries that describe allegedly real unidentified creatures that bear more than a passing resemblance to this supposedly mythical bogey beast. In 2007, Neil Powney from Basildon, Essex, wrote to the UK magazine Fortean Times revealing that during the 1970s, when she was 7-8 years old and living in the Corringham area of Essex, his…

A new low-cost sensor designed to resemble a sea turtle egg enables scientists to monitor nests remotely and predict when hatchlings will emerge almost to the day, providing invaluable information for conservation efforts and turtle nest management. Sea turtle populations worldwide are in decline due to human activities, with all seven species regarded as being threatened or endangered. Sea turtle conservation efforts largely focus on protecting vulnerable hatchlings once they emerge, to ensure they head out to sea, instead of toward the bright lights of towns. Conservationists can count the days since eggs were laid to predict when they will hatch and then watch the nest, but these efforts are inaccurate and labour-intensive. Detecting hatching In the current study, researchers used the TurtleSense system to monitor loggerhead sea turtle (Caretta…

On an island located some 48km (30ml) off the coast of San Francisco, a hoard of invasive house mice are threatening an ecological disaster on a scale far larger than what their small statures would suggest. These are the conclusions of a study led by LSU Associate Professor of Oceanography and Coastal Sciences Michael Polito, along with researchers from Point Blue Conservation Science, San Jose State University and California State University Channel Islands. The scale of the problem The island in question is Southeast Farallon Island, part of the Farallon Islands National Wildlife Refuge, home to the largest seabird breeding colony in the contiguous United States and many unique native species of plants and animals. Flouse mice are not native to the island but were unintentionally introduced during the 1800s…

Nature seems to have an inexhaustible supply of inspiration when it comes to butterflies. With over 18,000 species, each with a unique geometry and colour combination, butterflies look as though they're trying their best to imitate a sunbeam that crossed paths with a prism. Now a new study helps to put this incredible variation into a more focused perspective. The results align with a growing body of evidence that suggests butterfly-wing diversity really comes down to just a few simple ingredients in an ancient recipe that's stood the test of time. Experimenting to find what works “Evolution does not just mean change,” explains Andrei Sourakov, collections coordinator at the Florida Museum of Natural History's McGuire Center for Lepidoptera and Biodiversity, who led the research. “When it stumbles upon successful designs,…

FEATURE | PARASITES This group of reptiles can be affected by a range of internal parasites that localise within their gastrointestinal tract. In a recent study on seemingly healthy pet tortoises carried out in the UK, almost 50% of the animals were found to be shedding some parasites in their faeces without any obvious clinical signs of illness. Pinworms In the case of those tortoises that are most commonly kept as pets, oxyurids (pinworms) are the most frequently occurring parasite identified, especially in young Hermann's (Testudo hermanni) and Horsfield's (Agrionemys horsfieldii) tortoises. These are small worms measuring less than 7mm (0.25in) in length, and rarely cause any problems in low numbers. In fact, they have even been suggested to have a beneficial effect in churning up faecal matter and preventing…

The colourful species, which can grow up to 20cm (8in) long, originates from Yunnan province in China, where it inhabits ponds and slow-moving stretches of water. Up until 1995, it was considered to belong to the same species as the Himalayan crocodile newt (T. verrucosus), although it is much more brightly coloured and less aquatic in its habits. As with many amphibians, its conspicuous appearance serves as a warning, with regard to its toxic skin secretions, which protect it from predators. Nevertheless, large numbers of emperor crocodile newts are being caught and dried on a regular basis, to be used in traditional medicines, and increasingly, this species is coming under threat from habitat destruction as well. Breeding in the wild takes place between May and August. Outside this period, these…

FEATURE | BOSC'S MONITOR The two species of monitor lizard that are most commonly to be found in the hands of reptile enthusiasts are the Nile monitor (Varanus niloticus) and Bosc's monitor (Varanus exanthematicus) – otherwise known as the savannah monitor. Bosc's monitor is generally a dull greyish hue in terms of its overall coloration, while sometimes displaying occasional spots of burnt orange and dark green. Both sexes are similar in appearance, with the shape of the head being somewhat blunt around the snout, but becoming broader further back. The undersides of the body are normally white, sometimes with greyish coloured lines forming an irregular pattern here. This species has a particularly long, forked tongue, which is bluish in colour, becoming pinker at the tip. Like other related species, a…

The phrase “to swallow one's tongue” has been around since at least the 1880s and has been repurposed in several languages to mean everything from falling silent to a general feeling of fear. While it's anatomically impossible for a human to swallow their tongue, a new study shows that cane toads (Rhinella marina) achieve this feat each time they eat. This has now been confirmed by X-ray videography, which was used to study the toads'feeding behaviour, and provided the first glimpse of what this group of amphibians do with food once it is safely in the mouth. According to the results, cane toads swallow prey using a complex pulley system of cartilage and muscle that travels so far down their throat that it butts up against the heart. Too fast…

A new study by University of Maryland entomologists has revealed that the lifespan for individual honey bees kept in a controlled, laboratory environment is 50% shorter than it was in the 1970s. When scientists modelled the effect of today's shorter lifespans, the results corresponded with the increased colony loss and reduced honey production trends seen by U.S. beekeepers in recent decades. A new approach Colony turnover is an accepted factor in the beekeeping business, as bee colonies naturally age and die off. But over the past decade, U.S. beekeepers have reported high loss rates, which has meant having to replace more colonies to keep operations viable. In an effort to understand why, researchers have focused on environmental stressors, diseases, parasites, pesticide exposure and nutrition. This is the first study to…

FEATURE | SCENT MATTERS Communication between members of the same species, or even between animals of different species, is essential for many aspects of the individual's life. For those that live in groups, so the need to communicate is obvious, but even solitary species need to interact with others of their kind every now and then, particularly for mating purposes. Communication with same-sex rivals can also become much more significant at this stage too. Reptiles and amphibians have many different ways with which to communicate with one another. Sounds and visual displays are the most obvious and recognisable to the human observer. However, this does not mean that they are always the most conspicuous to the animals themselves. Scent output and recognition Many reptiles and amphibians use chemical cues to…

Q&A I have recently been researching full spectrum lighting for use in my yearling boa's new vivarium. I am particularly interested in the benefits of exposing him to UVA and UVB, and the associated health benefits. This snake is a Hog Island boa from the Cayos Cochinos, off the northern coast of Honduras. After browsing some weather websites, it appears that the UV levels in that area are fairly high on average, having a rating of 10 when I looked earlier today, but I am not sure how this will translate to a percentage from the bulb. The vivarium is fairly small. You are quite right that in the summer/hotter period, so an index of 8-10 is quite normal in this area. Long periods are averaging around 5-8 and there is…