Brian has two colour forms of the granuliferus, one red, and one lime green with a blue underside, beautiful.

Read full story, watch video: Frog Blog Manchester

Photo Robin Moore/iLCP

In a very short period of time, the team uncovered three amphibian species thought to be entirely new.

Read full story / see pix collections: Treehugger

Kirtland Peterson

“We are some of the first researchers to attempt to breed these animals into captivity and we have very little information about how to care for them,” said Brian Gratwicke, international coordinator for the project and a research biologist at the Smithsonian’s National Zoo, one of nine project partners. “We were warned that we might not be able to keep these frogs alive, but through a little bit of guesswork, attention to detail and collaboration with other husbandry experts — we’ve managed to breed them. The lessons we’re learning have put us on target to save this incredible species and our other priority species in Panama.”

Read full story: ScienceDaily

Kirtland Peterson

Three species hitherto unknown to science have been found in Colombia.

They include a poison-secreting rocket frog and two toads. All three are tiny and tend to be most active in daytime, which is unusual for amphibians.

However, the same expedition to Colombia failed to find the species it was hoping to rediscover, the Mesopotamia beaked toad.

The disappointment provoked by that non-discovery turned to glee when the conservation scientists came across the three new species.

Read full story: BBC / Science & Environment

Kirtland Peterson

A small environmental miracle has occurred in Beatty, Nev., a former mining town that sits on the eastern edge of Death Valley between Jackass Flats and Sober Up Gulch. The people of Beatty have helped revive the Amargosa toad, a warty, speckled, palm-sized creature that’s unique to the area and, just a few years ago, seemed headed for extinction.

But this is not your typical story of environmental action — the toad owes its comeback to an unlikely coalition that includes ranchers, miners, off-road racers, opponents of big government and the local brothel.

The toads come out at night, and twice a year around June, so does a team of volunteers assembled by the Nevada Department of Wildlife to count them. Shuffling through a cattle pasture armed with buckets and flashlights, Brian Hobbs, an amphibian biologist with the state, leads a group in gathering the toads. They live anywhere there is water.

Read full story and/or listen to podcast: KQED News

Kirtland Peterson

Although complete closures may sometimes be necessary, it is often possible to find creative solutions to conflicts that minimize impacts to sensitive species and in doing so help to build a constituency for conservation of the species.

The Williamson Rock issue seems to have all the hallmarks of a situation where a suitable compromise is attainable.

I hope the Angeles National Forest and Friends of Williamson Rock don’t let this opportunity slip away.

Read full story: Frog Blog

Kirtland Peterson

A frog discovered in Cuba currently holds the world record for the smallest frog. It’s also poisonous.

The record-holder for the smallest frog in the world apparently makes up for its miniature size by packing a wallop of poison, research reveals.

With a body that’s only 10 millimeters long, the Mount Iberia frog (Eleutherodactylus iberia) from Cuba currently holds the Guinness World Record for smallest frog.

Investigating these dwarf frogs is painstaking work, said researcher Miguel Vences, an evolutionary biologist at the Technical University of Braunschweig in Germany.

“You have to crawl on your knees and move leaf by leaf,” Vences told LiveScience. “And when you discover one of these frogs, they usually jump away immediately so that you have to start all over again.”

When Vences found his first specimen, he smelled a bitter odor and suspected it might be coated in toxic alkaloids.

“At the time I just mentioned this as a crazy and rampant speculation — I was sure it would prove to be wrong, and was even more surprised when my chemistry colleagues sent me the first results, stating they indeed had found alkaloids in the skins,” Vences said.

Only four other groups of frogs in the world secrete defensive toxins onto their skin, including the infamous poison-dart frogs of Latin America. It remains uncertain precisely how deadly this new poison dwarf might be.

The researchers suspect these dwarfs evolved their tiny size to better prey on mites overlooked as meals by larger frogs. These arachnids possess alkaloids the dwarfs secrete on their skins. And so by consuming the poison, the frogs somehow reallocated the goods for their own use. It was only later the frogs might have evolved their brown, yellow-striped appearance — “such a contrasting coloration usually is found in poisonous animals, which use it to deter potential predators,” explained researcher Ariel Rodriguez of the Institute of Systematic Ecology at Havana. A variety of tiny frogs roughly 10 millimeters long can be found around the world. These poisonous new findings could shed light on why this dwarf became so tiny.

A “more important question is probably why did the frogs not get even smaller?” Vences said. “In birds and mammals, who have to maintain a stable body temperature, you can understand why they cannot get smaller than a dwarf shrew or a tiny hummingbird — as the body surface relative to body volume increases as you get smaller, you are cooling more easily, so you need more energy to maintain your temperature. This only works to a certain size well above the 10 millimeters found in frogs.”

However, frogs, being cold-blooded, do not need to maintain a stable body temperature.

“So what is the limiting factor? Is it ecological, that there is not enough prey available for frogs under 8 to 10 millimeters?” Vences speculated. “Is it developmental, some fundamental processes in the body, like producing eggs, not being possible in smaller frogs? Physiological, related to water loss? In these questions, I see the greatest challenge, and this is where studies of miniaturization of vertebrates will be able to provide data of more fundamental importance, far beyond the pure curiosity of just their dwarf size.”

The scientists detailed their findings online Nov. 3 in the journal Biology Letters.

Source: Tehran Times

Kirtland Peterson

“It is very exciting and significant that we have bred these unusual frogs, as they are extremely difficult to breed. They are simply fascinating, from their behavior to their size,” said Marcy Sieggreen, Detroit Zoological Society curator of amphibians.

The mountain chicken frog, also called Leptodactylus fallax, is one of the largest frog species, with adults growing up to 8 inches long and weighing up to 2 pounds. Although once abundant in six of the Caribbean islands, the species is now confined to just Dominica and Montserrat. The frog was commonly hunted by islanders for food and is said to taste like chicken, which is how it got its name.

Read full story: DailyTribune

Kirtland Peterson

This danger mouse met a sticky end when crossing the path of the voracious African bull frog.

The pimpled and veiny behemoth has the self-satisfied air of one who takes pleasure in eating a hearty meal, even if it is a live rodent struggling for survival.

These carnivorous amphibians have an aggressive temper, can jump 12ft and have tooth like projections called odontoids, which are said to feel like broken glass when the bellicose beasts close their jaws.

Read full story: Daily Mail

Watch “Bullfrog Hunts… Anything”: YouTube

Kirtland Peterson

Here’s what it’s like to follow behind the herpetologists as they work their way down the trail in the early evening.

The sun set an hour ago and the air is starting to lose some of the afternoon’s heat, but your forehead and arms are still damp with a cool film of sweat. The full moon is rising through the trees ahead of you: a bright spot in the canopy that’s not strong enough yet to throw patches of moonlight on the forest floor. Everything in the understory is black, and everything in the midstory is black, and up in the canopy the leaves and branches are black against a night sky that is almost blue.

Photo by Alvaro del Campo

In the upper strata of the forest legions of stridulating insects are making a scritch-scritching chorus; to the right a far-off frog croaks once and falls silent; from the left comes an anxious-sounding hooting; a bat flutters past almost noiselessly, raising a tiny breeze; and ahead on the trail comes the rustling sound of the herpetologists searching through dry leaf litter.

Read full story: New York Times / Science

Kirtland C. Peterson

Reports of tadpoles with missing or deformed keratinized oral structures have increased. Yet, the impact missing teeth has on feeding remains unexplored. Here we use high speed videography (500 frames per second) of tadpoles of Southern Leopard Frog (Lithobates sphenocephalus [=Rana sphenocephala]) to study how missing teeth affect feeding. Specifically, we test the hypothesis that the number of teeth present correlates with two metrics of the effectiveness of a tadpole to rake material from a substrate. Those are the duration of the full gape cycle (opening and closing of the jaws) and of the closing phase (closing of the jaws once attached to a substrate).

We found a significant positive relationship between duration of time of the closing phase of the gape cycle and the number of labial teeth present. Thus, tadpoles with fewer teeth were in contact with a planar algal-covered substrate for a shorter duration than tadpoles with more teeth. Given the reports of tadpole mouthpart abnormalities, data relating feeding kinematics of tadpoles with missing labial teeth are relevant in assessing the impact these abnormalities have on larval performance. Our data indicate that tadpoles missing labial teeth forage less effectively than tadpoles with undamaged dentition.

This may help explain the pattern of reduced growth and developmental rates commonly observed in tadpoles raised in polluted environments or infected with pathogens that attack keratinized oral structures.

Source: Copeia 2010(3):481-486

Kirtland Peterson

Pet African dwarf frogs harboring salmonella have sickened at least 113 people, most of them children, researchers from the Centers for Disease Control and Prevention report.

“This is the first multistate outbreak of salmonella associated with frogs,” says Shauna Mettee, a public health nurse at the CDC in Atlanta who presented the findings October 22 in Vancouver, Canada, at a meeting of the Infectious Diseases Society of America.

CDC investigators became curious when doctors began reporting a spate of cases of the typhimurium subspecies of salmonella in 2009. Between April 2009 and March 2010, Mettee and her colleagues identified 113 cases of this infection, three-fourths occurring in children under age 10.

Read full story: ScienceNews

Kirtland Peterson

To be fair, some of the credit goes to an African frog.

In the wild, the African clawed frog produces antibacterial peptides — small chains of amino acids — on its skin to protect it from infection. Princeton researchers have found a way to attach these peptides, which can be synthesized in the laboratory, to a small electronic chip that emits an electrical signal when exposed to harmful bacteria, including pathogenic E. coli and salmonella.

Read full story: ScienceDaily

Journal Reference:

• Manu S. Mannoor, Siyan Zhang, A. James Link, C. McAlpine. Electrical detection of pathogenic bacteria via immobilized antimicrobial peptides. Proceedings of the National Academy of Sciences, 2010; DOI: 10.1073/pnas.1008768107

Kirtland C. Peterson

ABSTRACT: In the Sierra Nevada Mountains of California, Yosemite Toads (Anaxyrus canorus) have declined throughout their range where Brook Trout (Salvelinus fontinalis) have been widely introduced. Amphibians that evolved in fishless habitats often lack the necessary chemical defenses and behavioral responses to avoid predation. True Toads (family Bufonidae), however, possess noxious chemicals that often deter predators.

Our goal was to test whether eggs, tadpoles, and postmetamorphic toads of A. canorus are a palatable food source for S. fontinalis, assess the antipredator behavior of tadpoles of A. canorus by exposing them to various predator chemical cues, and determine sublethal effects on three lifestages of A. canorus from sampling by S. fontinalis.

We found that eggs, tadpoles, and postmetamorphic toads of A. canorus exhibit absolute unpalatability to S. fontinalis. In addition, tadpoles of A. canorus did not exhibit a significant difference in behavior when exposed to chemical stimuli. Moreover, observational experiments revealed that trout would sample, then reject lifestages of A. canorus unharmed, while trout readily consumed tadpoles of Pacific Chorus Frog (Pseudacris regilla).

We therefore infer that early lifestages of A. canorus likely possess existing chemical defenses as a result of interactions with native predators that adequately protect them from nonnative trout predation.

Although trout removal often leads to the recovery of other Sierra Nevada amphibian populations, trout removal would likely have no effect on populations of A. canorus given our results. Therefore, we suggest that other factors thought to be contributing toward A. canorus decline should be investigated before efforts are concentrated on removing trout from toad habitats.

Source: Copeia 2010(3):457-462.

Kirtland C. Peterson

The new species differs from its congers by the following combination of characteristics: SVL in adult males 11.3–12.1 mm and SVL in adult females 13.4–14.2 mm, skin on head and dorsum with co-ossification, general color in life orange with dorsal greenish irregular markings covered with small dark spots and dots, skull hyperossified, spinal processes of sacral and pre-sacral vertebrae hyperossified, and hyperossification of the distal end of the process of the fourth vertebra. The new species shares with most other Brachycephalus species remarkable traits, such as miniaturization and hyperossification of the skeleton. The new species probably occurs in isolation in highlands of the Atlantic Forest.

Full paper: BioOne September issue

This explains why the invasive toads have increased their rate of spread so dramatically, the researchers say.

They found that toads living at the very edge of their range were “super-invaders” – able to move beyond the boundaries of this existing habitat.

And when toads at the frontiers bred, their offspring inherited this ability to move quickly into new territory.

This phenomenon, which scientists have termed the Olympic Village Effect, has been proposed before, since these same scientists observed that the toads at the edge of the range had bigger front legs and stronger back legs – all the better to jump and to invade new areas.

Read full story: BBC Earth News

Kirtland C. Peterson

We used microsatellites to estimate genetic differentiation in populations that varied in distance from 1 to 60 km. Of 120 pairwise tests of genetic differentiation, 44 were significant. However, differentiation was low between all sites (F_ST = 0.0–0.087), almost all of the genetic variation being within populations (96.3%). Compared to published studies of other anuran species, populations of B. cognatus in southern New Mexico are among the most genetically homogenous anuran species.

Significant isolation by distance did occur over all populations despite the genetic similarity, suggesting that differentiation does occur at a broader scale. In addition, several landscape-based models of gene flow were produced and tested against the allelic data. A community model assigned each plant community a different level of resistance to gene flow. This model was not found to describe the estimated genetic variation between populations better than simple Euclidean distance.

However, the river model, which assigned low resistance to the aquatic habitats including the Rio Grande, described the estimated genetic variation better than Euclidean distance, suggesting that the Rio Grande, and potentially other rivers throughout the toad’s range, may act as a route of dispersal for B. cognatus, reducing genetic differentiation among distant populations.

Paper reference: Copeia 2010(3):388-396.

Read full post: Frog Blog