Tuesday, July 12, 2011

Decline in species shows climate change warnings not exaggerated

Forest frogs are temperature sensitive.
One in 10 species could face extinction by the year 2100 if current climate change impacts continue. This is the result of University of Exeter research, examining studies on the effects of recent climate change on plant and animal species and comparing this with predictions of future declines.

Published in leading journal Proceedings of the National Academy of Sciences (PNAS), the study uses the well-established IUCN Red List for linking population declines to extinction risk. The research examines nearly 200 predictions of the future effects of climate change from studies conducted around the world, as well as 130 reports of changes which have already occurred.

The research shows that on average the declines that have already happened match predictions in terms of the relative risk to different species across the world.

Many studies have predicted that future climate change will threaten a range of plants and animals with extinction. Some of these studies have been treated with caution because of uncertainty about how species will respond to climate change. But widely published research showing how animals and plants are already responding to climate change gave the Exeter team the opportunity to check whether the predictions were wide of the mark. By producing the largest review ever of such studies, they show that predictions have, on average, been accurate, or even slightly too cautious.

Lead author Dr Ilya Maclean of the University of Exeter said: "Our study is a wake-up call for action. The many species that are already declining could become extinct if things continue as they are. It is time to stop using the uncertainties as an excuse for not acting. Our research shows that the harmful effects of climate change are already happening and, if anything, exceed predictions."

The study covered a wide range of species in all types of habitat across the globe. The findings confirm that human-induced climate change is now a threat to global biodiversity.

Co-author Dr Robert Wilson, also of the University of Exeter, said: "By looking at such a range of studies from around the world, we found that the impacts of climate change can be felt everywhere, and among all groups of animals and plants. From birds to worms to marine mammals, from high mountain ranges to jungles and to the oceans, scientists seem to have been right that climate change is a real threat to species.

"We need to act now to prevent threatened species from becoming extinct. This means cutting carbon emissions and protecting species from the other threats they face, such as habitat loss and pollution."

Examples of existing responses to climate change:

Decreased ice cover in the Bering Sea reduced the abundance of bivalve molluscs from about 12 to three per square metre over a very short period of time (1999-2001). These shells are the main food source for species higher up the food chain, such as Spectacled Eider.

Climatic warming and droughts are causing severe declines in once-common amphibian species native to Yellowstone National Park in the United States of America. Between 1992-1993 and 2006- 2008, the number of blotched tiger salamander populations fell by nearly half, the number of spotted frog populations by 68 per cent, and the number of chorus frog populations by 75 per cent.

In Antarctica, few animals exist on land, but one of the most abundant, a nematode worm living in the soil in dry, cold valleys experienced a 65 per cent decline between 1993 and 2005 as a result of climate change.

Examples of predicted responses to climate change:

On Tenerife, an endemic plant, the Caňadas rockrose has a 74 to 83 per cent chance of going extinct in the next 100 years as a result of climate change related droughts.

In Madagascar, climate warming is predicted to cause endemic reptiles and amphibians, often found in mountain ranges, to retreat towards the summit of the mounts. With a warming of just two degrees Celsius, well within current projections, three species are predicted to lose all of their habitat.

Birds living in northern Boreal Forests in Europe are expected to decline as a result of global warming. Species such as Dotterel are predicted to decline by 97 per cent by 2100 and species such as Two-barred Crossbill and Pine Grosbeak could lose their entire range within Fenno-Scandia.


Citation
Ilya M. D. Maclean and Robert J. Wilson. 2011. Recent ecological responses to climate change support predictions of high extinction risk. PNAS 10.1073/pnas.101735

Reproductive Isolation and the Monterey Ensatina

Ensatina eschscholtzii. Photo Credit Chris Brown
Lungless salamanders (Ensatina eschscholtzii) live in a horseshoe-shape region in California (a 'ring') which circles around the central valley. The species is an example of evolution in action because, while neighboring populations may be able to breed, the two populations at the ends of the arms of the horseshoe are effectively unable to reproduce.

New research published in BioMed Central's open access journal BMC Evolutionary Biology showed that this reproductive isolation was driven by genetic divergence rather than adaption to different ecological habitats.

Researchers used genetic variation to determine 20 distinct populations of salamanders and focused in detail at 13 zones where the populations were able to cross breed. Results showed that the diversification of salamander populations was associated with significant genetic divergence, both nuclear and mitochondrial, and also with strong ecological divergence, in the plants and climate within their habitats.

However the ability to cross-breed was only associated with nuclear divergence. At contact zones around the ring up to 75% of the salamanders were hybrids, including second generation and back crosses to the parental populations but at the ends of the ring only 5.7% were hybrids and all of these were first generation F1 hybrids which rarely reproduced.

Dr Pereira said, "Evidence from E. eschscholtzii shows that the ecological environment, which may drive species formation, does not necessarily drive reproductive isolation. Instead, reproductive isolation of this 'ring' species of salamanders appears to be due to processes such as length of time in geographic isolation which are related to overall genetic divergence." Full article available on-line.

Citation
Ricardo J Pereira, William B Monahan and David B Wake. 2011. Predictors for reproductive isolation in a ring species complex following genetic and ecological divergence. BMC Evolutionary Biology doi:10.1186/1471-2148-11-194

Monday, July 11, 2011

The Herpetofauna of Trinidad and Tobago Website

The website Herpetofauna of Trinidad and Tobago and associated blog are now functional. However, the website is a work in progress and needs photos and text. If you can help with that please contact us. JCM

Smooth Green Snake Release in Libertyville, Illinois

The Buffalo-GrovePatch is reporting the introduction/release of the smooth green snake (Liochlorophis vernalis ) in into the Old School Forest Preserve in Libertyville, Illinois

Half were sent directly into the wild (so-called “hard release”), while half were released into pre-release enclosures within the preserve (so-called “soft release”) where they will spend some time getting accustomed to being wild while still being contained in a controlled, managed environment designed to limit predators of the snake. Over the course of the summer about a dozen more snakes will be released – some of which will have very tiny radio transmitters affixed to them so the biologists are better able to track their movements and keep tabs on their survival success rates.

An exceptionally small insectivore, these snakes are difficult to spot in their grassland prairie habitat. They are also difficult to find because they have become so rare in Illinois. A collaborative conservation effort between Lincoln Park Zoo and Lake County Forest Preserves aims to boost their population numbers through scientific study, breeding, monitoring and reintroduction efforts.

Lake County Forest Preserves Wildlife Biologist Gary Glowacki explained that for more than a decade the District has purchased and/or restored a significant amount of lands containing suitable smooth green snake habitat. “Despite this, the snake is still found only in a handful of isolated areas in Lake County that contain remnant grassland habitat,” he said. “The remaining populations may not be viable in the long-term due to small numbers and because habitat fragmentation, primarily due to roads and other physical barriers, makes re-colonization of restored sites improbable.”

According to the Illinois Comprehensive Wildlife Action Plan and Strategy, the smooth green snake is identified as a Species in Greatest Need of Conservation. Populations of this species are declining due to habitat loss, conversion of grasslands into agriculture, urbanization, and the widespread use of pesticides. “Currently, Illinois only has less than 1 percent of its pre-settlement prairie acreage remaining, so species that depend on grasslands are in need of conservation,” said Lincoln Park Zoo Reintroduction Biologist, Allison Sacerdote.

With little chance of natural recovery, the Lake County Forest Preserves and the zoo established a partnership in 2010 to aid the recovery process through population supplementation, translocation, and reintroduction into suitable habitat.

The partnership’s first challenge was to locate the snakes last summer – not an easy proposition with such a small population of tiny snakes that blend in so well with the grasses. But hard work paid off when a few adult snakes were located and brought to the zoo for breeding, and a large communal nest of more than 80 smooth green snake eggs was discovered in an undesirable location that is slated for development. The eggs were taken to the zoo for incubation and 83 neonates hatched in mid-summer 2010.

The biologists and animal care staff at the zoo are breaking new ground with the care and study of this species. Very little is known about it as there are no published accounts of any other accredited zoo ever caring for this species, and very few scientific studies related to the species. As such, the team is employing a number of different rearing and reintroduction techniques for the neonates to determine which methods garner the highest success rate.

“We hope that this recovery program will not only restore a more robust population of this species in Illinois, but our work may also be a model for other organizations and regions seeking to help this species recover,” Sacerdote said.

Sunday, July 10, 2011

Death From Python Case Set for Jury Selection

A story by Stephen Hudak, at the Orlando Sentinel (Follow the link to find the complete story) is reporting that the court case against Charles "Jason" Darnell, 34, and Jaren Hare, 21 is ready to start jury selection on Monday July 11. The couple is accused of failing to keep the 8-foot-6-inch albino Burmese python from slithering out of a terrarium in July 2009 and into bed with the toddler, Shaianna Hare. The python constricted the 2-year-old in her crib. Darnell and Hare will stand trial for manslaughter and child neglect. The couple will be tried together and could receive a sentence of 35 years in prison if convicted of all charges.

Animal rights groups and animal-law experts across the U.S. will be monitoring the criminal case, thought to be the first instance of a nonvenomous constrictor killing a child in Florida, where the thriving but invasive "reptile of concern" spurred state-sponsored python hunts in the Everglades in 2009.

According to investigative documents reviewed by the Sentinel, the yellowish constrictor, bought at a flea market for $200, hadn't eaten in a month and was kept in a glass terrarium with a quilt for a lid. The snake weighed in at a sickly 13.5 pounds after the attack.

Since 1980, the Humane Society of the United States, which opposes ownership of constrictor snakes, has documented more than 200 incidents of snake attacks, escapes, abandonments and cruelty cases in 43 states. The reptiles have been linked to the deaths of 16 people in the U.S., including seven children. A similar trial resulted in a misdemeanor conviction for a father in 2002. In that case, a Pennsylvania judge decided that snake keeper was guilty of misdemeanor child endangerment but not guilty of involuntary manslaughter and reckless endangerment in the death of his 8-year-old daughter. The girl was constricted by the father's 11-foot-long pet python.


The Rise and Rise of the Flying Reptiles

Extremes in pterosaur morphology.
The giant and probably flightless
 Quetzalcoatlus from the Late
Cretaceous of Texas was as tall a
s a giraffe. The small insectivorous
Anurognathus from the Late Jurassic
of Germany is seen flying above
 the artist’s head. Drawings by
Mark Witton.

University of Bristol Press release issued 6 July 2011
Pterosaurs, flying reptiles from the time of the dinosaurs, were not driven to extinction by the birds, but in fact they continued to diversify and innovate for millions of years afterwards.

A new study by Katy Prentice, done as part of her undergraduate degree (MSci in Paleontology and Evolution) at the University of Bristol, shows that the pterosaurs evolved in a most unusual way, becoming more and more specialized through their 160 million years on Earth. The work is published today in the Journal of Systematic Paleontology.
‘Usually, when a new group of animals or plants evolves, they quickly try out all the options.  When we did this study, we thought pterosaurs would be the same,’ said Katy.  ‘Pterosaurs were the first flying animals – they appeared on Earth 50 million years before Archaeopteryx, the first bird – and they were good at what they did.  But the amazing thing is that they didn’t really begin to evolve until after the birds had appeared.’
Katy’s study was done in conjunction with her supervisors, Dr Marcello Ruta and Professor Michael Benton. They looked at 50 different pterosaurs that ranged in size from a blackbird to the largest of all, Quetzalcoatlus, with a wingspan of 12 metres, four times the size of the largest flying bird today, the albatross. They tracked how all the pterosaur groups came and went through their history and recorded in detail their body shapes and adaptations.

The new work shows that pterosaurs remained conservative for 70 million years, and then started to experiment with all kinds of new modes of life. After birds emerged and became successful, the pterosaurs were not pushed to extinction, as had been suggested. It seems they responded to the new flyers by becoming larger and trying out new lifestyles. Many of the new lifestyle adaptations were seen in the pterosaurs skulls, as they adapted to feed on different food sources; some were seed-eaters, many ate fish, and later ones even lost their teeth. The rest of the body also showed a surprising amount of variation between different groups, when considering that the body forms have to retain many features to allow flight.

‘Pterosaurs were at the height of their success about 125 million years ago, just as the birds became really diverse too,’ said Dr Marcello Ruta. ‘Our new numerical studies of all their physical features show they became three times as diverse in adaptations in the Early Cretaceous than they had been in the Jurassic, before Archaeopteryx and the birds appeared.’
Pterosaurs dwindled and disappeared 65 million years during the mass extinction that killed the dinosaurs.  In their day they had been a fair match for the birds, and the two groups divided up aerial ecospace between them, so avoiding conflict.

‘We’re delighted to see a student mastering some tough mathematical techniques, and coming up with such a clear-cut result,’ said Professor Michael Benton. ‘Paleontologists have often speculated about the coming and going of different groups of animals through time, but the new study provides a set of objective measurements of the relative success and breadth of adaptation of pterosaurs through their long time on the Earth.’
Further information can be found on the Palaeobiology and Biodiversity Research Group's website: The rise and rise of the flying reptiles.

The drawings on this page are by paleontologist and freelance palaeoartist, Dr Mark Paul Witton.  For more information about his work visit: MarkWitton.com

Paper
‘Evolution of morphological disparity in pterosaurs’ by Katherine C. Prentice, Marcello Ruta and Michael J. Benton in Journal of Systematic Palaeontology

Saturday, July 9, 2011

Evolution in Body Size in Monitor Lizards

The Monitor lizards of the genus Varanus have radiated into a variety of habitats that range from extreme desert to very wet tropical forests, as well as grasslands and mangroves, and the genus contains species that are dedicated carnivores as well as omnivores, and fruit-eaters. In fact, even a quick survey of the 73 species of monitors and it obvious that their common ancestor was remarkably successful with descendants now distributed from Africa and Asia to Australasia. Body size in these lizards is also diverse, ranging from the largest living lizard, the Ora or Komodo Dragon, Varanus komodoensis, which can weigh more than 100 kg and reach 3 m total length, to the quite small pygmy monitors (V. brevicauda and V. primordius) with weights of about 10 g and lengths of about 20 cm total length. David C. Collar and colleagues have now examined the factors involved in producing the huge range of body sizes seen in monitor lizards. They found adult body size spans four orders of magnitude in adult body mass and more than an order of magnitude in total length. Undoubtedly monitor lizards have the largest size range found in any genus of living vertebrates. Therefore Varanus provides an opportunity to investigation the causes and consequences of body size evolution. Their research shows that the diverse body sizes that occur in this clade is a consequence of different selective demands imposed by three major habitat use patterns—arboreal, terrestrial, and rock-dwelling. The authors reconstruct phylogenetic relationships and ancestral habitat use and applied model selection to determine that the best-fitting evolutionary models for species’ adult size are those that infer oppositely directed adaptive evolution associated with terrestrial life styles and rock-dwelling, with terrestrial lineages evolving extremely large size and rock-dwellers becoming very small. Additionally, they found habitat use affects the evolution of several ecologically important morphological traits independently of body size divergence. They suggest that habitat use exerts a strong, multidimensional influence on the evolution of size and shape in monitor lizards.

The small, rock-dwelling Varanus baritji,
the large, semi-aquatic Varanus salvator, and the
medium -sized  arboreal, 
Varanus prasinus.
Citation
Collar, D. C., Schulte II, J. A. and Losos, J. B. (2011), EVOLUTION OF EXTREME BODY SIZE DISPARITY IN MONITOR LIZARDS (VARANUS). Evolution. doi: 10.1111/j.1558-5646.2011.01335.x

Holes in Fossil Bones Reveal Dinosaur Activity

Bone foramen graph: The y-axis is an index of the amount of blood flow through the foramen in relation to the body size of mammals (red), reptiles (blue) and dinosaurs (orange-red). Image courtesy of Professor Roger Seymour, School of Earth & Environmental Sciences, University of Adelaide.
New research from the University of Adelaide has added to the debate about whether dinosaurs were cold-blooded and sluggish or warm-blooded and active.

Professor Roger Seymour from the University's School of Earth & Environmental Sciences has applied the latest theories of human and animal anatomy and physiology to provide insight into the lives of dinosaurs. The results will be published this month in Proceedings B, the Proceedings of the Royal Society B (Biological Sciences), and can now be found online at: http://dx.doi.org/10.1098/rspb.2011.0968

Human thigh bones have tiny holes - known as the 'nutrient foramen' - on the shaft that supply blood to living bone cells inside. New research has shown that the size of those holes is related to the maximum rate that a person can be active during aerobic exercise. Professor Seymour has used this principle to evaluate the activity levels of dinosaurs.

"Far from being lifeless, bone cells have a relatively high metabolic rate and they therefore require a large blood supply to deliver oxygen. On the inside of the bone, the blood supply comes usually from a single artery and vein that pass through a hole on the shaft - the nutrient foramen," he says.

Professor Seymour wondered whether the size of the nutrient foramen might indicate how much blood was necessary to keep the bones in good repair. For example, highly active animals might cause more bone 'microfractures', requiring more frequent repairs by the bone cells and therefore a greater blood supply.

"My aim was to see whether we could use fossil bones of dinosaurs to indicate the level of bone metabolic rate and possibly extend it to the whole body's metabolic rate," he says. "One of the big controversies among paleobiologists is whether dinosaurs were cold-blooded and sluggish or warm-blooded and active. Could the size of the foramen be a possible gauge for dinosaur metabolic rate?"

Comparisons were made with the sizes of the holes in living mammals and reptiles, and their metabolic rates. Measuring mammals ranging from mice to elephants, and reptiles from lizards to crocodiles, one of Professor Seymour's Honours students, Sarah Smith, combed the collections of Australian museums, photographing and measuring hundreds of tiny holes in thigh bones.

"The results were unequivocal. The sizes of the holes were related closely to the maximum metabolic rates during peak movement in mammals and reptiles," Professor Seymour says. "The holes found in mammals were about 10 times larger than those in reptiles."

These holes were compared to those of fossil dinosaurs. Dr Don Henderson, Curator of Dinosaurs from the Royal Tyrrell Museum in Alberta, Canada, and Daniela Schwarz-Wings from the Museum für Naturkunde and Humboldt University Berlin, Germany, measured the holes in 10 species of dinosaur from five different groups, including bipedal and quadrupedal carnivores and herbivores, weighing 50kg to 20,000kg.

"On a relative comparison to eliminate the differences in body size, all of the dinosaurs had holes in their thigh bones larger than those of mammals," Professor Seymour says.

"The dinosaurs appeared to be even more active than the mammals. We certainly didn't expect to see that. These results provide additional weight to theories that dinosaurs were warm-blooded and highly active creatures, rather than cold-blooded and sluggish."

Professor Seymour says following the results of this study, it's likely that a simple measurement of foramen size could be used to evaluate maximum activity levels in other vertebrate animal groups, both living and fossils.

Tuesday, July 5, 2011

An Essay on Human Attitudes Towards Snakes

Two-edged charm of the snake
Michael Bywater/The Independent
(Arabian Standard Time) Oman Time

They’re lithe. They’re sinuous, graceful and elegant. Beautifully-ornamented, they shimmer in the sunlight. They have elegant cheekbones and a steady, challenging gaze.

They are silent and indolent, until roused, when they flow like volitional quicksilver. They can swallow things bigger than their head. If they were courtesans or burlesque artistes, they would be rich and notorious. They’re snakes. The fear of snakes is said to be on a par with those other leading phobias, the terror of speaking in public, or flying.

Snakes remain a shorthand for horror and malignity. Think of Indiana Jones in the snake pit, or the factory-chimney-sized anaconda in the imaginatively named Anaconda. Think of Snakes on a Plane (what is it about snake movies that cripples the imagination of the people who think up the titles?).

Sometimes the phobia goes to the very limits of creative horror. I was once summoned across London at four in the morning to assist a friend who couldn’t go to bed. A visitor had left, on her bed, a copy of the National Geographic magazine which she knew contained, somewhere, a picture of a snake; she was unable to enter the bedroom until I had come and removed it from her flat. That’s how bad snake-horror can be.

Count me out.
I love snakes. I admire their ancient silence, the flicker of their tongues as they taste the air, the sheen on a rainbow boa, dull dun indoors but, in the sunlight, iridescent, like petrol on water. I love the shape of their heads and the precision of their movements.

On the web you can find a photograph of the king cobra breeder and conservationist Luke Yeomans of Nottinghamshire, holding an adult male. It’s arched forward, stretching out from his hand. It is an amazing animal.

Yeomans wanted to create a ‘living ark’ for them, and spoke of his ‘lifetime love’ and his concern that this “end-of-the-line, apex predator” could eventually disappear from the wild.

Yeomans had intended to open his snake sanctuary to the public today. But, the apex predator lived up to his name, struck at him, and he died. For a man who had devoted 30 years to these magnificent animals, it was a strangely glorious way to leave the planet, and indeed, such a death would lead to his instant apotheosis.

My own favourite snake was a reticulated python called Betty. Betty was a constrictor, a relatively merciful snake which suffocates its prey (some species slowly swallow their luncheon alive), not just by the standards of snakes but by the standards of most predators. Dogs rip the guts out of their prey; cats play terrible, agony-prolonging games with theirs. Yet we welcome them into our homes and called them “Good boy!” and snuggle up to them in the evening as we watch Simon Cowell.

But if you’ve never snuggled up to 18 feet of python (not that big; they can grow to almost 30 feet long) you’ve never snuggled. And the knowledge that your snugglee could, without effort, eat Simon Cowell’s head adds a strange feeling of peace to the proceedings.

But an affection for, and admiration of, snakes is a tricky thing to admit. It’s a pit-bull sort of species in the popular imagination; a slavering, well-dodgy bastard biding its time.

People who keep snakes have tattoos, hang out on BDSM websites, live in Arizona trailer homes, ride motorcycles and hold up liquor stores. Or otherwise they live alone in an apartment in New York with 75 venomous snakes and eventually, when life gets too much for them (or, perhaps, not enough), they end it all, as Aleta Stacey is thought to have done last week by allowing a black mamba to bite her, and doing nothing to save themselves from death.

We mistake snakes for primitives, as though they are so steeped in ancient evil they haven’t even evolved legs. But we’re wrong; evolution has created the snake by taking away the legs of a proto-lizard, and their literally serpentine form is not crudity, but sophisticated adaptation.

Nor are they in any sense evil. They are simply snakes.

Giving out the speech day prizes at a well-known prep school last year, I was taken to see the snake club, which was a club devoted to snakes.

The biology master handed me a strong, healthy serpent which immediately swarmed up my arm, around my neck, down my other arm, laid its head on my wrist, and began to lick the back of my hand. This, for a herpetophile, is as flattering as it gets.
He then – the biology master, not the snake – told me that the journalist James Delingpole had been to visit the school for his young son. Delingpole, he said, was another snake bloke, but he and my snake didn’t hit it off. In fact, the snake bit Delingpole in the face and wouldn’t let go until it felt the point had been made. “What was interesting,” said the snake master, “was that he sent his son here anyway. As if he thought, yup, they’ve got snakes who bite your face, that’s the place for my boy.”

One has, of course, one’s limits. In the Australian outback once, I had a king brown – known locally, with laconic pastoral accuracy as the “fierce snake” – in my hat. My hat.

I wish I could tell you how fast a startled fierce snake can shift, but I was too busy shifting myself in the opposite direction to notice.

Fatality From Captive King Cobra

 Sue Turnbull told the inquest how she lowered Luke, who had 'turned purple', to the ground before attempting CPR and injecting him with adrenalin as paramedics rushed to the scene. The partner of tragic snake expert Luke Yeomans made a desperate bid to save his life after he was bitten by a King Cobra, his inquest heard today. But despite their efforts, which included administering shots of anti-venom, the 46-year-old died at the King Cobra sanctuary he kept behind his home in Eastwood, Nottinghamshire. The inquest also heard the incident was so rare that the Liverpool School of Tropical Medicine, the only laboratory in the UK capable of analysing snake venom, did not have a 'test' for that produced by a King Cobra.  However, coroner Mairin Casey said that based on the evidence, she was satisfied that the cause of death was a 'snake bite'.The hearing in Nottingham heard how Luke was working alone with his snakes in an outbuilding when he was attacked last Wednesday. The rest of the story can be found at Mail-On-line

Dog Deaths on the Increase from Adder Bites in the UK

The pets are among many small animals that have been attacked after startling the snakes as they bask in the sunshine and had to be put down as the venom ravaged their organs. Two dogs have died after being bitten by poisonous adders that are out in unusually large numbers because of the hot weather. Dog owners are now being warned to be on their guard to prevent any more deaths from the species, which is found throughout the Britain Isles.he latest victim was a ten-year-old King Charles Spaniel which was bitten as she played in a back garden in Canvey Island, Essex. Daisy-May was being looked after by Carol Toplis, 57, while her owner was in hospital for a knee operation.'It was really nasty. The venom attacked her organs. She became very sleepy, it was as though she'd had major surgery,' said Mrs Toplis. The whole story and phots are at Mail On-line.

Most of World's 'Missing Species' Live in Known Hotspots

A very large, undescribed bufonid 
from southern Thailand. JCM
DURHAM, N.C. – Most of the world's "missing" or undiscovered species live in regions already identified by scientists as conservation priorities, according to a new study published this week in the journal Proceedings of the National Academy of Sciences.

The study's findings suggest recent conservation efforts have been on target and should reduce uncertainty over global conservation priorities, its team of international authors say. But, they add, the extinction threat for many of the as-yet undiscovered species is worse than previously feared.

"We show that the majority of the world's 'missing species' are hiding away on some of the most threatened landscapes in the world," says Stuart Pimm, Doris Duke Professor of Conservation at Duke University's Nicholas School of the Environment. "This considerably increases the number of threatened and endangered species around the world."

With limited resources and accelerating threats to nature, conservation biologists have long sought to identify areas around the world where effective conservation actions could save the most species. Biodiversity hotspots — places with extreme rates of habitat loss as well as unusually high numbers of endemic species – are priorities.

The problem is that knowledge of species is seriously incomplete — many species are as-yet unknown.

"We know we have an incomplete catalogue of life," says lead author Lucas Joppa of Microsoft Research in Cambridge, U.K., who received his PhD in ecology from Duke in 2009. "If we don't know how many species there are, or where they live, then how can we prioritize places for conservation? What if the places we ignore now turn out to be those with the most unknown species?"

To address this dilemma, Joppa and his coauthors created a model that incorporates taxonomic effects over time to estimate how many species of flowering plants, which form the basis of the biodiversity hotspots concept, remain to be discovered in regions around the world. They then compared those estimates with regions currently identified as global conservation priorities. The two sets matched.

Six regions already identified by conservation scientists as hotspots – Mexico to Panama; Colombia; Ecuador to Peru; Paraguay and Chile southward; southern Africa; and Australia – were estimated by the models to contain 70 percent of all predicted missing species. Only two regions with high estimates of missing species – the region from Angola to Zimbabwe, and the northern Palearctic, which encompasses parts of Europe and Asia – contained no biodiversity hotspots.

"It was a huge relief that those places in which we are already investing our resources are also those which house the majority of the world's undiscovered species," says David Roberts of the Durrell Institute of Conservation and Ecology at the University of Kent. "It didn't have to turn out that way!"

Norman Myers of Oxford University and the originator of the "hotspots" idea, says, "these findings really validate all of the time and effort I have put into fighting for the preservation of the world's biodiversity. Now we can get on with trying to save these unique and threatened places."

While showing that conservation action is already directed at the most appropriate places, the study's results bring an increased sense of urgency to the global extinction crisis.

The authors stress that results like these make it even more important to effectively conserve large areas of land.

"How can you save a species you don't even know exists?" asks Joppa. "You can't. But you can protect places where you predict they occur."

Fossil Salamanders From Southern Appalachia

The Seal Salamander, Desmognathus 
monticola Dunn, 1916. JCM
Salamanders, particularly the lungless plethodontids, are specious in the southern Appalachia. More than 60 species can be found in the streams and on the forest floor, and at some locations the ir may be as many as 15 species living together. The cool, wet, ancient forests that have survived to the present seem to have created ideal conditions for the lungless salamanders to radiate into dozens of ecological niches. Now, Boardman and Schubert report on the fossil salamander fauna found at the Gray Fossil Site in northeastern Tennessee. A diverse fossil salamander assemblage of the Mio-Pliocene (4.7-7 MYA) has been uncovered, and it includes at least five taxa (Ambsytoma, Plethodon, Spelerpinae, Desmognathus, and Notophthalmus) from three families (Ambystomatidae, Plethodontidae, and Salamandridae, respectively), all of these taxa are present in the area today and support the hypothesis that a woodland-pond environment was present at the site of the site. The fossils document the earliest records for these families in the Appalachian Mountains, as well as representing the earliest records for plethodontids and ambystomatids east of the Mississippi River. The full article can be found by following the link below.

Sunday, July 3, 2011

A New Species of Tortoise - From Tiburon Island, Mexico


A team of researchers investigated a desert tortoise from the Southwest USA and northwestern Mexico. What was thought to be a simple problem in species identification turned out to be a very complex matter. Their investigations required forensic genetics and several other methods. In the end, they found it necessary to describe a new species. More than that, the discovery has very important implications for conservation and the development of the deserts of southern California.
The new species, Morafka's Desert Tortoise
 (Gopherus morafkai) from Tiburon Island,
Sonora, Mexico. Photo courtesy of Taylor
 Edwards, 2010.

The new species, Morafka's Desert Tortoise (Gopherus morafkai) from Tiburon Island, Sonora, Mexico. Photo courtesy of Taylor Edwards, 2010.

Since the original description of Agassiz’s Land Tortoise, scientifically called Gopherus agassizii, facts have been nothing less than Dazed and Confused Oneundred and fifty years ago in 1861, James Graham Cooper described a new species of tortoise from the deserts of California. From the get-go, factual confusion has been more common than not. The publication date has consistently been inappropriately attributed to 1863, and even the original common name, Agassiz Land Tortoise, was inexplicably changed to the Desert Tortoise, a moniker that is commonly used today. But there’s more than just a new name.

For 150 years, Agassiz’s Land Tortoise has been masking the existence of at least two species whose distributions are restricted to either side of the Colorado River. Prof. Bob Murphy of the Royal Ontario Museum, Toronto, Canada and the Kunming Institute of Zoology, Chinese Academy of Sciences, and colleagues from the US Geological Survey, Arizona Research Laboratories, California Academy of Sciences, and Lincoln University have now started to unravel a Gordian knot. As if coming straight out of an episode of the TV series CSI, they went into the laboratory and obtained DNA data from the original 150-year-old type specimen, as well as from a more recently described species inhabiting the tip of the Baja California peninsula. The effort in forensic genetics documented that the named species was from California, and not Arizona as sometimes claimed. The enigmatic species from Baja California was previously thought to be a transplant from Tiburon Island, Sonora, Mexico, but turns out to be from California, or at least its founding mother was from there. All of this meant that the population in Arizona and adjacent Mexico was an unnamed, new species, one whose identity had been hidden for more than a century.

The new rock-dwelling species, Gopherus morafkai, is named for the late Prof. David J. Morafka, a pioneer in tortoise research. The results of the research are published in the open access journal ZooKeys.

More than a species description.
The recognition of Morafka’s Desert Tortoise means that Agassiz’s Desert Tortoise has lost a whopping 70 percent of its range! Arizona and adjacent Mexico can no longer serve as a genetic reservoir for the Western species. And given that the Western species was already listed as being threatened because of drastic decline in the number of individuals—a consequence of disease, urban expansion and habitat destruction—the description of the new species may turn up the heat on politicians and developers with respect to the massive construction of solar energy sites in prime Desert Tortoise habitat in the Mojave Desert. Perhaps this flagship centurion of the Southwest should be upgraded to Endangered status? Because Morafka’s Desert Tortoise has lost 30% of its range, perhaps protection for this species should be fast-tracked? Only time will tell.

The complete story remains untold. The knot remains untied. It is possible that Morafka’s Desert Tortoise may consist of two species. And so, back to the field and lab goes the team, inspired by knowing that Dave Morafka would be very pleased with the progress.

Friday, July 1, 2011

Suzio Report - Hands-Off Snakes at Dens

Howdy Herpers,

As some of you will remember, the last Suizo Report mentioned an alligator lizard with red banding on its back. At the time of discovery, one member or our party suggested that the red signified that this was a female that was gravid. This suggestion brought forth a flood of replies, not a one which whole-heartedly agreed with the diagnosis. I could, of course, cut and paste everything that other people said, but that would generate even more dialogue on a subject that is in severe need of scientific analyses. I'm of the opinion that none of us know for sure what is up with coloration in Elgaria kingii.

I will paraphrase what was said by everybody, and be finished with the subject. If anybody has seen anything in lit land, please let me know. Otherwise, we all, myself included, are just speculating based on our own experience.

Some are in the camp that states that yes, they change color in May and June. But it appears to be more with males than females. These are folk who are only talking about wild populations. I am in this camp, but freely admit that I don't know enough to be sure.

Also popular with other field folk is that their color is only a relic of their substrates. These people would agree with what comes next. 

Others, mainly keepers of the California species, state that they flat out never change color. Several have had females lay eggs, without any color change. In other words, whatever color they were when collected is the color they stay. Males or females, no change.

I think it was a great discussion, and thanks to all who participated. What I have walked away with from this discussion is that many of us think this is a very cool species of lizard that deserves more attention. I know I that will certainly be more focused on them in the years ahead, and know several of you will be doing the same. Cool! And thanks everybody...........

Also, for the benefit of those of us who thought the first cerberus found on 3 May 2011 was both a female and pregnant, the info that I received from the cerberus pros would indicate that she was indeed a she. As for being pregnant, some thought it possible, but could not say for sure from the image provided. We can probably safely say that she was either pregnant, or about to defecate.

Enough history. And on to more history!

I am slowly but surely scanning some of the 35mm slides in my collection. The very best moments of my life occurred back in the day when that was the best way to take photographs. In particular, 1990 through 2000 was the time period when I scored numbers that easily triple the snake numbers that I see today. While some of this phenomena can be attributed to being younger, lighter, stronger, faster and more motivated, there is more involved than that. The early-to-mid 1990s brought us consistent precipitation in both the winter and the summer. Whereas the average rainfall in this century has been ~9 inches, it was ~12 inches in the 1990s.

Also, as mentioned in an earlier missive, I was inclined in the early part of Y2K to get grabby at atrox dens. I remain convinced that this worked wonders in declining visuals at the dens themselves. Another reason for lower snake counts might have something to do with radio-tracking individuals. The time it takes to do datasheets alone could be impacting the counts. But the bottom line is that the 1990s were my glory years, and I'm pleased to share with some images part of what I learned.

All captions are placed above the images.

Pic 1: Ron's Den, 19 March 1995. This photo was taken the day we found the den. The big snake that is plied on top of the others even earned a name. Said name was Tyson, for he ruled this den in a most aggressive fashion. I learned much from watching this den in a hands off fashion. I will only go in depth on two of the phenomena I learned at this den for now. They were (and still are--this den is still thriving, I'm just afraid to go there now): 1.  Desert Tortoises are overwintering with the snakes here, and 2. So are pack rats. Let's go to the next picture, where the importance of the pack rat to the hibernaculum will be discussed.
 

Pic 2: Atrox with food bolus, just outside of a den we call "Dan's Den," which is located at Saguaro National Park East. This photo was taken in February of 1999. Dan's den was first discovered by Dan Bell, and I was there for the first time in January of 1993. Every winter from 1993 until this photo was taken (1999), the place was packed with both snakes and pack rat debris. Take a look at the food bolus in this snake. Does it look like it could be a pack rat? The den was empty the next fall, and had zero pack rat debris packed inside it. I have not seen an atrox in or at this den since the spring of 1999. I do believe this boy ate himself out of house and home! (No--the pack rats are not safe with their playmates during the colder winter months).
 

Pic 3: Image taken 19 March, 1999. This is from AD1 on our study plot. The den was discovered just one month prior to this image. It was after dark when I approached the pair, and saw their tails intertwined. They were in a peaceful posture, but as soon as the flash went off the snake "woofed" at me, and is viewed rising into a defensive posture. Go on to Pic 4.

Pic 4: There are two things evident in this image. The first is that the female is escaping into the crevice ahead of the male. The male is holding his ground, and did so until the female was all the way. He then followed her. This form of "mate defense" was evident at many of the hands off dens I had. The boys are protecting the girls! The second thing that is evident is that the the girl is the very first female atrox we ever put a transmitter in. Good old CA1, "Ruth." We knew her two years before we knew her!

Pic 5: Suizo Mountains AD1, 6 March 2001: This image was taken ten days before we captured CA1 to formally begin our study. Let's just bop on to Pic 6: 


Pic 6: AD1, 9 March 2001. 7 days before we snagged CA1. I do believe that our second subject, CA2 "Dianna" is the snake with the rattle showing on the left. Be we did not actually catch her until 22 March. 

Ever since we started this study, the snakes have stopped basking on the apron en masse like this. To be sure, most returned, most showed fidelity to the site. But when they basked, they moved away from the den apron. I'm not damning telemetry or our study with these words. I'm just saying that before you mess with any animal at a den site, know what you will lose as a result! 

On a positive note, we are keeping our hands off this den now. It is starting to come back to what it used to be.

Pic 7: Pikachu Den, Hill 97, 20 November 1999. Once again, we did science at this den. Grab fest, PIT tag, release, and it was never the same. But once again, we are keeping our hands off, and it is coming back. If you look carefully behind the snakes, you will see there is a tortoise in the hole with them. 

OK. I'm pleased to report that last spring, we found a few new atrox dens that will be monitored with hands off fashion for as long as we are able to do it. I still have yet to find anything as good as Ron's Den, or Pikachu, but I'll keep trying.

Best to all, roger