Amphibian research with glow sticks


This video from the USA says about itself:

5 August 2013

Eastern (Red-Spotted) Newt

Did You Know?

•The eastern (red-spotted) newt is a widespread and native salamander of New York State and eastern North America that can live for 12-15 years!
•Adults and larvae use gills to breathe and live in water; however, juveniles (also known as “efts”), become land dwellers and develop lungs to breathe air.
•The eastern (red-spotted) newt secretes poisonous toxins, and the eft’s bright coloration serves as a warning to predators.
•Eastern newts use specialized chemicals to find food and attract mates.
•They help reduce mosquito populations by feeding on their larvae.

From Penn State university in the USA:

Use of glow sticks in traps greatly increases amphibian captures in study

November 7, 2017

With amphibian populations declining around the world and funds to find the causes scarce, a team of Penn State researchers has shown that an unorthodox tactic will make it easier and therefore less expensive to capture adult salamanders and frogs.

The researchers demonstrated that glow sticks — cheap, self-contained, short-term light-sources — attract the creatures to traps set in vernal pools where they come to reproduce in the spring. The translucent plastic tubes contain isolated substances that, when combined, make light through chemiluminescence.

Often used for recreation, glow sticks are sometimes relied upon for light during military, police, fire or emergency operations. However, they have not been widely used in wildlife research and their appeal to amphibians is not well understood, according to David Miller, assistant professor of wildlife population ecology, College of Agricultural Sciences.

“This work is important because research funding is often limited, especially when we’re talking about amphibians and reptiles compared to mammals or other charismatic species,” he said. “With a warming climate, monitoring data will become only more important for informing conservation decisions. If we can find a way to improve our capture rate, it is going to mean less time, effort and expense to study amphibians.”

As part of a long-term national study, Miller’s lab has been monitoring amphibian populations at sites around Pennsylvania. Spearheading that effort has been David Munoz, doctoral degree candidate in ecology, who helped create the Salamander Population Adaptation Research Collaboration Network, or SPARCnet. It was his idea to “bait” traps with glow sticks at one site as an experiment. The researchers chose State Game Land 176 in Centre County, managed by the Pennsylvania Game Commission. The research using glow sticks took place in a forested area known as the Scotia Barrens, which contains a dense network of vernal pools where Miller’s lab has been monitoring amphibian populations for years.

Within this network, researchers surveyed 12 pools, varying in size but with similar habitat characteristics — no aquatic vegetation and leaf-litter bottoms. Each pool dries mid- to late-summer in most years. Surveys for this experiment were conducted in March and April 2015, and traps were continuously deployed during surveys.

Over the course of nine trapping nights, researchers captured 4,935 amphibians. Glow sticks increased the average number of captures of spotted salamanders by more than three times, Jefferson salamanders by nearly four times, wood frogs by almost three times and Eastern newts by as much as six times, compared to control traps.

The research, which was published in Herpetological Review, focused on adult amphibians, noted lead researcher Michael Antonishak, an undergraduate majoring in wildlife and fisheries science when the study was done. He worked closely with Munoz on the project.

Past studies found that baiting traps with glow sticks increased the capture rates of larval amphibians two to eight times compared to funnel traps with no lure, but no studies have tested the effectiveness of glow-stick lures on the capture rates of adult, vernal pool-breeding amphibians, Antonishak pointed out.

“We specifically focus on the adult stage of amphibians because life history suggests adults play the most critical role in population persistence,” he said. “Capturing adults also make techniques such as mark-recapture feasible, providing estimates of abundance and survival to improve conservation decisions.”

Why are glow sticks effective lures for capturing amphibians? Researchers are not sure, Munoz admitted. It is likely a straightforward visual cue, but it could be more than that.

It is generally accepted that amphibians do not eat while they are breeding but it is possible that the light actually attracts different organisms that the amphibians may eat — perhaps the amphibians are gravitating toward those species, he explained.

“Without actually testing that, we can’t say for sure,” Antonishak added. “Are they attracted to the light itself or is it possible that the amphibians just see a little better in the pool where glow sticks are illuminating the water? Perhaps females, for instance, see males a little better and they are more attracted to them.”

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What a prehistoric salamander ate


Phosphotriton sigei

This picture shows a three-dimensional reconstruction of the skeleton of Phosphotriton sigei gen. et sp. nov. (B), scaled to the same length as other Eurasian urodeles: a European plethodontid, Hydromantes italicus Dunn, 1923 (A), and two salamandrids, Hypselotriton orientalis (David, 1873) (C) and Salamandra salamandra (Linnaeus, 1758) (D).

From ScienceDaily:

Ancient petrified salamander reveals its last meal

Researchers identify frog bones within the stomach of a 35 million year old ‘mummified’ salamander fossil using advanced x-ray imaging techniques. At least six kinds of organs are preserved in almost perfect condition

October 3, 2017

A new study on an exceptionally preserved salamander from the Eocene of France reveals that its soft organs are conserved under its skin and bones. Organs preserved in three dimensions include the lung, nerves, gut, and within it, the last meal of the animal, according to a study published in the peer-reviewed journal PeerJ by a team of palaeontologists from France and Switzerland.

Accessing the complete anatomy of an extinct animal, i.e. both its external and internal aspects, has often been the dream of palaeontologists. Indeed, in 99% of cases, fossils are only represented by hard parts: bones, shells, etc. Fossils preserving soft tissues exist, but they are extremely rare. However, their significance for science is enormous. What did the animal look like? What did they eat? How did they live? Most of these questions can be answered by exceptionally preserved fossils.

The newly studied fossil externally looks like a present-day salamander, but it is made of stone. This fossil “mummy” is the only known specimen of Phosphotriton sigei, a 40-35 million years old salamander and belongs to the same family as the famous living fire salamander (Salamandra salamandra).

It is unfortunately incomplete: only the trunk, hip and part of hind legs and tail are preserved. Until very recently, the only thing palaeontologists could tell about this specimen was visible anatomical details, such as the cloaca, the orifice used for reproduction and by digestive and urinary canals. Indeed, though it was discovered in the 1870s, it was never studied in detail.

Thanks to recent synchrotron technology, its skeleton and various organs could be studied. The specimen was scanned at the ID19 beamline of the European Synchrotron Radiation Facility (ESRF) in Grenoble (France). This modern technology gave access to an incredible level of details that could never have been achieved before without slicing the specimen into a series of thin sections.

The quality of preservation is such that looking at the tomograms (equivalent of radiograms) feels like going through an animal in the flesh. At least six kinds of organs are preserved in almost perfect condition, in addition to the skin and skeleton: muscles, lung, spinal cord, digestive tract, nerves, and glands.

But the most incredible is the preservation of frog bones within the stomach of the salamander. Salamanders almost never eat frogs or other salamanders, though they are known to be quite opportunistic. Was it a last resort meal or a customary choice for this species? This, unfortunately, will probably never be known.

These new results are described by Jérémy Tissier from the Jurassica Museum and the University of Fribourg in Switzerland, and Jean-Claud Rage and Michel Laurin, both from the CNRS/Museum national d’histoire naturelle/UPMC in Paris.

Author Michel Laurin notes, “This fossil, along with a few others from the same lost site, is the most incredibly well-preserved that I have seen in my entire career. And now, 140 years after its discovery, and 35 million years after the animal died, we can finally study it, thanks to modern technology. The mummy returns!”

Common frog and frog spawn video


This video, made in May 2017 in the Netherlands, shows common frogs during their mating season and the resulting frog spawn.

Stanley Quarré made this video.

The harp music is by Anne Vanschothorst.

‘Prehistoric frog ate dinosaurs’


This 2014 video about Beelzebufo ampinga is called Prehistoric News : Devil Frog had Spikes and Armor.

From Sci-News.com:

Giant Prehistoric Frogs Ate Small Dinosaurs, Claim Scientists

Sep 20, 2017

Exceptionally large individuals of Beelzebufo ampinga, an extinct species of frog that lived in Madagascar during the Late Cretaceous epoch, about 68 million years ago, were capable of eating small dinosaurs, according to an international research team led by California State Polytechnic University scientists.

This conclusion comes from a study of the bite force of extant South American horned frogs (genus Ceratophrys).

“Unlike the vast majority of frogs which have weak jaws and typically consume small prey, horned frogs ambush animals as large as themselves — including other frogs, snakes, and rodents,” explained co-author Dr. Marc Jones, from the University of Adelaide and the South Australian Museum.

“And their powerful jaws play a critical role in grabbing and subduing the prey.”

Dr. Jones and co-authors from the United States, the United Kingdom, and Australia found that small horned frogs, with head width of about 1.8 inches (4.5 cm), can bite with a force of 30 newtons (N), or about 3 kg/6.6 lbs.

A scaling experiment, comparing bite force with head and body size, calculated that large horned frogs that are found in the tropical and subtropical moist lowland forests of South America, with a head width of up to 4 inches (10 cm), would have a bite force of almost 500 N. This is comparable to reptiles and mammals with a similar head size.

“This would feel like having 50 liters of water balanced on your fingertip,” explained lead author Professor Kristopher Lappin, of California State Polytechnic University.

“Many people find horned frogs hilarious because of their big heads and fat, round bodies,” said co-author Sean Wilcox, a PhD candidate at the University of California, Riverside.

“Yet, these predators have given us a rare opportunity to learn something more about the biology of a huge extinct frog.”

The team estimated the bite force of the extinct frog Beelzebufo ampinga may have had a bite up to 2,200 N, comparable to formidable mammalian predators such as wolves and female tigers.

“At this bite force, Beelzebufo ampinga would have been capable of subduing the small and juvenile dinosaurs that shared its environment,” Dr. Jones said.

“This is the first time bite force has been measured in a frog,” Professor Lappin said.

“And, speaking from experience, horned frogs have quite an impressive bite, and they tend not to let go.”

“The bite of a large Beelzebufo ampinga would have been remarkable, definitely not something I would want to experience firsthand.”

The study appears today in the journal Scientific Reports.

Ancient amphibians’ teeth, new study


This video says about itself:

23 January 2016

The first major groups of amphibians developed in the Devonian period, around 370 million years ago, from lobe-finned fish which were similar to the modern coelacanth and lungfish. These ancient lobe-finned fish had evolved multi-jointed leg-like fins with digits that enabled them to crawl along the sea bottom.

Some fish had developed primitive lungs to help them breathe air when the stagnant pools of the Devonian swamps were low in oxygen. They could also use their strong fins to hoist themselves out of the water and onto dry land if circumstances so required.

Eventually, their bony fins would evolve into limbs and they would become the ancestors to all tetrapods, including modern amphibians, reptiles, birds, and mammals. Despite being able to crawl on land, many of these prehistoric tetrapodomorph fish still spent most of their time in the water. They had started to develop lungs, but still breathed predominantly with gills.

From the University of Toronto in Canada:

Ancient amphibian had mouthful of teeth ready to grab you

September 15, 2017

The idea of being bitten by a nearly toothless modern frog or salamander sounds laughable, but their ancient ancestors had a full array of teeth, large fangs and thousands of tiny hook-like structures called denticles on the roofs of their mouths that would snare prey, according to new research by paleontologists at the University of Toronto Mississauga (UTM).

In research published online in a recent issue of PeerJ, an open access journal, Professor Robert Reisz, Distinguished Professor of Paleontology at UTM, explains that the presence of such an extensive field of teeth provides clues to how the intriguing feeding mechanism seen in modern amphibians was also likely used by their ancient ancestors.

They believe that the tooth-bearing plates, ideally suited for holding on to prey, such as insects or smaller tetrapods, may have facilitated a method of swallowing prey items via retraction of the eyeballs into the mouth, as some amphibians do today.

In many vertebrates, ranging from fish to early synapsids (ancestors of mammals), denticles are commonly found in dense concentrations on the bones of the hard palate (roof of the mouth). However, in one group of tetrapods, temnospondyls (which are thought to be the ancestors of modern amphibians) these denticles were also found on small, bony plates that filled the large soft part of the palate. The entire roof of the mouth was covered with literally thousands of these tiny teeth that they used to grab prey. Since these toothy plates were suspended in soft tissue, they are often lost or scattered during fossilization.

Denticles are significantly smaller than the teeth around the margin of the mouth — on the order of dozens to a couple hundred microns in length. They are actually true teeth, rather than just protrusions in the mouths of these tetrapods, says Reisz and his colleagues, Bryan Gee and Yara Haridy, both graduate students in paleontology.

“Denticles have all of the features of the large teeth that are found on the margin of the mouth,” says Reisz. “In examining tetrapod specimens dating back ~289 million years, we discovered that the denticles display essentially all of the main features that are considered to define teeth, including enamel and dentine, pulp cavity and peridontia.”

In reaching these conclusions, the researchers analyzed [Permian age] specimens unearthed from the fossil-rich Dolese Brothers Limestone Quarry near Richards Spur, Oklahoma. They were extraordinarily well preserved, making them ideal candidates for study.

The researchers extracted and isolated the denticle-bearing plates, created thin section slides and examined them under the microscope — no small feat since denticles on this animal were only about 100 microns long.

Reisz and his graduate students suggest that the next big question relates to evolutionary changes to the overall abundance of teeth: if these ancient amphibians had an astonishing number of teeth, why have most modern amphibians reduced or entirely lost their teeth?

British government threatens great crested newts


This video from Britain says about itself:

26 May 2015

A short video detailing the life of a female great crested newt (Triturus cristatus) broadcast on the BBC television show Springwatch. Michaela narrates the story of a female newt who has just come out of hibernation and is looking for a mate. The clip is from the first episode of Springwatch from 2015.

By Peter Frost in Britain:

An endangered delight

Friday 1st September 2017

The rare dragon newt is under threat from housing development – best try and spot it while you can, suggests PETER FROST

NEW rules and how they are interpreted by Natural England, Defra and Michael Gove, the Minister for Environment, Food and Rural Affairs, are making it much easier for builders to disturb and move populations of one of our most exotic wild animals, the rare and threatened great crested newt (Triturus cristatus), also known as the dragon newt.

Perhaps this change of policy is a payback to some of the Tory house builders and developers that he met and begged donations from in his time as shadow minister of housing from 2007 to 2010.

The new guidelines will certainly do nothing to preserve and promote this spectacular but threatened [amphibian] that is such a brave sight in our ponds.

The “dragons” in my local pond arrived late this year. Snow, and weather cold enough to freeze the pond, had delayed their arrival.

Once the weather warmed up the black beasts with their fire bellies and their darting tongues entertained us with their curious mating dance among the reeds and lily pads.

It’s a delight to lie on the side of the pond and quietly watch these rare creatures. They might only be six or seven inches long but close up they are as impressive as any dragon in a story book. Years ago as a young boy I kept them as pets in a fish tank. We know better now and today this particular newt is one of the most protected animals in Britain and Europe.

The great crested is the biggest and least common of the three newts found in the British Isles. Another similar amphibian is the smooth or common newt (Lissotriton vulgaris, but still listed in many books as Triturus vulgaris). This species is found throughout Britain and is the only newt species to be found in Ireland.

It can grow to four inches and is the species most often found in ponds, including garden ponds, during the breeding season between February and June.

Britain’s other small brown newt is the Palmate (Triturus helveticus). It is a little smaller than the Smooth Newt, rarely reaching three inches.

It has a definite preference for shallow ponds on acid soils and is most commonly found on heathland in the south and west and, in the north, on moorland and in bogs.

A good field guide and many websites will have pictures to help you recognise the three species.

Since the war, populations of great crested newts have declined in most of Europe including in Wales and Scotland. Heavily protected by law, it clawed its way back. Now in Gove’s safe hands, who knows its fate.

If you want to identify dragon newts, look for dark grey-brown backs and flanks, and a covering of darker-coloured spots so they appear almost black. Their undersides are either bright yellow or orange-coloured and are covered in large, black blotches. Real experts can recognise individual newts by the unique blotch patterns on their undersides.

Only the males have a spectacular jagged crest, which runs along their backs, during the breeding season. A separate, smoother-edged crest runs above and below their tails.

Females have no crest but have a yellow-orange stripe along the lower edge of their tails and often an orange stripe along their backs and tails.

The newts normally live on land but take to ponds to breed. A larger male performs a spectacular courtship display, a kind of dance during which he deposits a small packet of sperm in the path of the female.

Then he swims sideways in front of her to gently encourage her into a position where the packet will be pressed against her and picked up by her cloaca, her sexual opening. It’s sex, but not as we know it.

Once fertilised, the female can start to lay two or three eggs a day. She will keep laying for as long as four months until 200 to 300 eggs have been laid.

The eggs, each carefully wrapped in a leaf, are laid on submerged aquatic plants. The larvae or efts hatch after about three weeks and then live in the pond as aquatic predators. The newts will have chosen a pond with no fish as they eat the efts.

The latter transform into air-breathing baby newts at about four months old, when they move on to dry land until they are old enough to breed in two or three years’ time.

Throughout October to March, adult newts hibernate under logs and stones or in the mud at the bottom of their breeding ponds.

The newts normally return to the same breeding site each year and can live as long as 25 years, although up to about 10 years is more usual.

If, like me, you like nature a bit more out of the box did you know that many serious Loch Ness Monster hunters believe Nessie is in fact a giant newt or the closely related salamander? It was identified as such as long ago as 1931. The shape was always right until forged pictures started the illusion of the long, dinosaur-like neck.

Both Chinese and Japanese giant salamanders grow to nearly six feet. They love deep, dark waters and are so secretive that they are rarely ever seen. You can make up your own mind.

Purple frog new species discovery in India


External morphology of tadpoles of the Bhupathy’s purple frog (Nasikabatrachus bhupathi). Image credit: S. Jegath Janani et al.

By Natali Anderson:

Bizarre New Species of Frog Discovered in India: Nasikabatrachus bhupathi

Aug 28, 2017

Herpetologists are claiming they have discovered a new species of purple frog living in the Western Ghats, India.

In a paper published in the Alytes, the International Journal of Batrachology, the researchers describe the new frog species that they call Nasikabatrachus bhupathi.

The proposed English name is the Bhupathy’s purple frog.

The new species was described by Dr. S. Jegath Janani from the Centre for Cellular and Molecular Biology (CSIR-CCMB) in Hyderabad, India, and his colleagues from the American Museum of Natural History the CSIR-CCMB, and the Nature Environment and Wildlife Society.

“The name of this species, bhupathi, commemorates Dr. S. Bhupathy, a noted scientist and a field herpetologist,” the authors explain.

They say Nasikabatrachus bhupathi is just the second member of the genus Nasikabatrachus.

The frog is morphologically, acoustically and genetically distinct from the only previously known species, Nasikabatrachus sahyadrensis (common names: purple frog, Indian purple frog, pignose frog).

Nasikabatrachus bhupathi measures between 1.8 and 2 inches (4.5-5 cm) in length.

“The abdominal skin of the species is smooth, grayish-white with faint marbling in coloration. The skin on dorsum is smooth, thick, and dark brown from vent to shoulder. The head is lighter brown; no dorso-lateral or transverse skin folds,” Dr. Janani and co-authors say.

“The body is globular; the head is not externally distinct from body, the snout is acutely pointed with a lighter colored fleshy protuberance and a hard knob-like projection at the tip.”

“The mouth is small, subterminal, ventral, and posterior to snout tip; the tongue is small with entire rounded tip.”

According to the team, Nasikabatrachus bhupathi lives on the eastern slopes of the Western Ghats.

“The currently known distribution of Nasikabatrachus bhupathi is restricted to three highly seasonal second order streams,” they say.

“The type locality is on the leeward side of the Western Ghats, which receives less rainfall than the western slopes of these mountains during southwest monsoon.”

Both Nasikabatrachus bhupathi and N. sahyadrensis are highly adapted for fossoriality (burrowing).

Nasikabatrachus frogs live and feed underground, therefore hard, dry soil and rock (from mountain uplift) is expected to present an insurmountable barrier to burrowing and feeding, preventing them from dispersing far,” the researchers say.