Thursday, May 29, 2014

Common Asian toad invasive in Madagascar

Common Indian Toad. Duttaphrynus melanostictus. Front view. 
Photograph by L. Shyamal
The unique wildlife of Madagascar is facing an invasion of toxic toads that could devastate the island’s native species. Snakes feeding on the toads are especially at risk of poisoning, as are a host of other animals unique to the island — such as lemurs and endemic birds — and the species could cause harm to humans as well.

In a letter to Nature published today, 11 researchers warn that Asian common toads (Duttaphrynus melanostictus) were observed near Toamasina, the African country’s largest seaport, in March. It is suspected that the amphibians arrived from Asia in shipping containers, and are now taking advantage of what the writers describe as “ideal resources and climate” to establish themselves.

“Time is short, so we are issuing an urgent call to the conservation community and governments to prevent an ecological disaster,” say Jonathan Kolby, a wildlife-health researcher at James Cook University in Townsville, Australia, and his colleagues.

The discovery of the invasive amphibians recalls the Australian plague of cane toads (Rhinella marina). These animals, relatives of the Asian common toad, were deliberately introduced to Australia in 1935; they proceeded to devastate native animal populations and have spread across much of the country, defying attempts to eradicate them.

Kolby and his colleagues warn that something similar could now happen in Madagascar.

The toads are already reported to have been deadly to snakes, including the ground boa (Acrantophis spp.), which is found nowhere else, Kolby tells Nature. Drawing parallels with the cane-toad situation, he warns that more than 50 species of endemic snake could be threatened, because they are likely to eat the toxic toads. Iconic Madagascan species such as the cat-like fossa (Cryptoprocta ferox), lemurs and endemic birds are also in jeopardy. And the toads could spread diseases to other amphibians and even contaminate drinking water and transmit parasites to humans.

The species is not yet widespread in Madagascar, but it has been found a mere 25 kilometers away from the important Betampona nature reserve, and a short distance further from other internationally important biodiversity hotspots. It is unclear how fast it can travel, but cane toads have been clocked expanding their range at 50 kilometers per year.

The potential tragedy is not restricted to Madagascar. “There is now a high dispersal risk of these toads spreading from Madagascar to other Indian Ocean islands such as the Mascarene Islands, Comoros and Seychelles,” says Kolby.

Toads are already being collected and removed, he says, and the Madagasikara Voakajy, a non-governmental organization in Antananarivo devoted to biodiversity, is tracking the spread of the amphibians. The toads should be hunted, their spawn should be destroyed and ponds should be drained to stop their breeding, says Kolby. “We are still within the early stages of population growth,” he says. An eradication program should be developed swiftly, “while populations are still relatively small and manageable”.

Mark Hoddle, director of the Center for Invasive Species Research at the University of California, Riverside, notes that to be considered invasive, a non-native species must have established a reproductive population that spreads and causes environmental and economic damage. On this basis it may be too early to declare the Asian toad in Madagascar a problem species, he says, but there are “very good reasons to be concerned”.

Citation
Kolby, J. E. 2014. Ecology: Stop Madagascar's toad invasion now Nature 509. doi:10.1038/509563a



A new blunt-snouted dyrosaurid from the time of Titanoboa

An ancient crocodilian has been named after the fictional Balrog creature in J.R.R. Tolkien's Lord of the Rings series. The ancient 16-foot, 900-pound blunt-snouted dyrosaurid was given the name, Anthracosuchus balrogus, in a new study from The University of Florida. The huge crocodilian was featured in a 2012 Smithsonian Channel documentary about Titanoboa, a massive 58-foot python that also lived around 60 million years ago. Anthracosuchus balrogus was unearthed from the same layer of rock as Titanoboa in the Cerrejon coal mine of northern Colombia. Smithsonian has the full Titanoboa documentary available on YouTube. 

Alex Hastings, a postdoctoral researcher at Martin Luther Universitat Halle-Wittenberg and former graduate student at the Florida Museum of Natural History and UF's department of geological sciences, says in a statement, "It quickly became clear that the four fossil specimens were unlike any dyrosaur species ever found. Everyone thinks that crocodiles are living fossils that have remained virtually unchanged for the last 250 million years. But what we're finding in the fossil record tells a very different story."

Jonathan Bloch, co-author and Florida Museum associate curator of vertebrate paleontology, says crocodyliforms that lived in the Cerrejon ecosystem during the Paleocene, when temperatures were higher than today, grew to enormous sizes. He says A. balrogus lived in close proximity to Titanoboa.

Bloch says, "Every once in a while, there was likely an encounter between Anthracosuchus and Titanoboa. Titanoboa was the largest predator around and would have tried to eat anything it could get its mouth on."
A giant turtle, Carbonemys cofrinii, also lived during the time of Titanoboa and A. balrogus.

Citation
Hastings, A. K., Bloch, J. I., & Jaramillo, C. A. (2014). A new blunt-snouted dyrosaurid, Anthracosuchus balrogus gen. et sp. nov. (Crocodylomorpha, Mesoeucro
codylia), from the Palaeocene of Colombia. Historical Biology, (ahead-of-print), 1-23.

Wednesday, May 28, 2014

Intranasal neostigmine reduces mortality in a mouse model of Naja naja envenomtion

Snakebite is one of the most neglected of all tropical diseases, with nearly 5 million people bitten by snakes each year and fatalities globally up to 30 times higher than that of land mines and comparable to AIDS in some developing countries. It has been estimated that more than 75 percent of snakebite victims who die do so before they ever reach the hospital so a new approach may dramatically reduce the number of global snakebite fatalities, currently estimated to be as high as 94,000 per year. 
Such a fast, accessible, and easy-to-administer treatment for venomous snakebite may be coming. Not soon, the regulatory process allows no shortcuts and clinical trials are expensive, but it is in the works. 
Researchers have reported on a pilot study geared toward developing a universal antidote for snakebite. Last summer, the team tested the effectiveness of a nasally administered antiparalytic drug on mice injected with high doses of Indian cobra (Naja naja) venom. Mice injected with otherwise fatal doses of venom outlived and in many cases survived after being treated with the antiparalytic agent, neostigmine.
Although the mice in this experiment were each treated only once to maintain a consistent protocol, a nasally administered antidote could, in practice, be administered multiple times without needles. Inhibitors of other types of venom could be combined with those working against paralysis to form a complete antidote. With many combinations for potential testing, the team is now working intensively with chemist and snake venom expert, Dr. Sakthivel Vaiyapuri of Reading University in the United Kingdom, a co-author on the report. 


Separate groups of mice were given varying doses of venom (all above lethal limits) and then treated with the antiparalytic treatment at two different time intervals: within 1-2 minutes after envenomation and 10 minutes after envenomation. 10 of 15 mice given the lowest dose of venom, followed by the treatment within 10 minutes, survived and later exhibited completely normal behavior, while 100 percent of control mice died. In groups given higher doses of cobra venom (2 to 5 times the lethal dose) all mice succumbed, but those treated with a single dose of neostigmine survived significantly longer than the controls. 
"Antivenom is necessary, but not sufficient to manage this problem. Its limitations are fairly well known at this point and we need a better bridge to survival. It's ironic that virtually every medical organization and practitioner wears the snake symbol, yet we have no real effective treatments for the people getting bitten," says Dr. Matthew Lewin of the California Academy of Sciences. "Ninety-eight percent of snakebite victims live in poverty, which is perhaps why funding and innovation are lacking. The bottom line is that no one should die from a snake bite in the twenty-first century, and we're optimistic about this promising step."
The team initially demonstrated the potential of this novel snakebite treatment during an experiment conducted in April of 2013 at the University of California, San Francisco. In that experiment, a healthy human volunteer was paralyzed, while awake, using a toxin that mimics the effects of the venom of cobras and other snakes that disable their victims by paralysis. The experimental paralysis progressed from eye muscle weakness to respiratory distress in the same order typically seen in snakebite victims. The team then administered the nasal spray and within 20 minutes the patient had recovered. The results of that experiment were published in the medical journal Clinical Case Reports.
In late June of 2013, Samuel, Dr. C. Soundara Raj, and colleagues at TCR Multispeciality Hospital in Krishnagiri, Tamil Nadu, India accelerated the recovery of a snakebite victim on life support using this method. After receiving 30 vials of antivenom, the standard treatment for venomous snakebites, the female patient remained weak and suffered from facial paralysis. Within 30 minutes of treatment with the antiparalytic nasal spray, the patient's facial paralysis was reversed. Two weeks after being treated, the patient reported having returned to her daily activities. 
Citation
Matthew R. Lewin, Stephen P. Samuel, David S. Wexler, Philip Bickler, Sakthivel Vaiyapuri, and Brett D. Mensh 2014.  Early treatment with intranasal neostigmine Reduces Mortality in a Mouse Model of Naja naja (Indian Cobra) Envenomation,” Journal of Tropical Medicine, vol. 2014, Article ID 131835, 6 pages, 2014. doi:10.1155/2014/131835


A new mode of reproduction in a new frog



Nyctibatrachus kumbara 
Forty different modes of reproduction have been described in frogs, now a 41st mode has been described. The newly described kumbara night frog, Nyctibatrachus kumbara, inhabits stream and river beds traversing the forests of the southern India’s Western Ghats is the only known amphibian to coat its eggs in mud.

Kotambylu Vasudeva Gururaja of the Indian Institute of Science in Bangalore and colleagues, discovered the frog during expeditions which started in 2006. The new frog has only been found in swamp forests in the Karnataka region of the Western Ghats, where nutmeg trees form a dense canopy.

At dusk, male kumbara night frogs attract females with a distinctive "tok" call. If a female wishes to reproduce with him, the two stand on their hind legs, the female rotates into a handstand, and lays about five pigmented eggs on to a twig or some other plant structure.

"Kumbara" means "potter" in Kannada, a local language. "The male frog shows such finesse when it applies mud to the eggs," says Gururaja.

The male then moves toward the egg clutch, stands on his hind limbs, collects mud from the stream bed with its forelimbs and spreads it on the eggs. He repeats this about 15 times, covering all the eggs with mud.
This is the first time such behavior has been observed in amphibians. "I have never heard of or observed mud packing in any amphibian," says Sathyabhama Das Biju at the University of Delhi in India, who was not involved with the study.

There are some straightforward explanations. "Since the eggs are laid about six centimeters above the water, there is a chance they can go dry," says Gururaja. "The mud pack could be preventing that. It could also be a camouflage against egg predators like crabs, insects and snakes."


But more fundamentally, Gururaja thinks the frogs just need to be different from their neighbors. Two closely related species of Nyctibatrachus, Jog's night frog and Rao's dwarf wrinkled frog, live in the same area. Gururaja found that the three species differ in many ways; they are different sizes, make different calls, mate differently and care for their young differently.

Citation

GURURAJA, K. V., DINESH, K., PRITI, H., & RAVIKANTH, G. (2014). Mud-packing frog: A novel breeding behaviour and parental care in a stream dwelling new species of Nyctibatrachus (Amphibia, Anura, Nyctibatrachidae). Zootaxa,3796(1), 33-61.


Wednesday, May 21, 2014

Climate change: amphibians & latitude

The changing climate is impacting organisms worldwide. Perhaps the most obvious change is in the timing of events; Japanese cherries are blossoming earlier than they have for the last 1000 years, some migrating birds arrive at their summer grounds in the northern hemisphere several weeks earlier than they did only 50 years ago, and others lay two, not one, clutches of eggs per season. However, the directional trend towards earlier phenology conceals substantial variation among populations, species and higher. For example, great tit, Parsus major, and blue tit, Cyanistes caeruleus, populations in Western Europe show considerable variation in their phenological response to climate change, despite climate change itself being relatively uniform across this geographic range. Tree swallows, Tachycineta bicolour, in North America differ geographically in their response to local climate change, with western and more southern populations exhibiting a stronger response to climate change than eastern and northern populations. Finally, the phenological response of both pied flycatchers, Ficedula hypoleuca, and European starlings, Sturnus vulgaris, has been shown to differ between the two species and between geographical locations. Despite considerable evidence for differences in phenological response to global warming between species and regions, the causes of this variation remain poorly understood.
Although mostly studied in birds and plants, the taxon that shows the strongest average shift towards earlier breeding is amphibians. Amphibian populations have, on average, advanced their breeding date at least twice as much compared to other animal taxa for which comparable data exist. However, population changes in breeding phenology in amphibians are also surprisingly variable. For example, only 2 out of 7 studies of common toads report earlier breeding in more recent years, and a recent study of 10 amphibians found significant shifts in only 40% of species. The combination of large average responses and high heterogeneity among populations and species calls for studies that attempt to address the causes of this variation. This will enable better predictions for changes in breeding phenology across different species and across different scenarios of global warming. Population responses to novel environments in general, and global warming in particular, should depend on the species biology (e.g. which environmental cues trigger reproduction), the ecological conditions (e.g. to what extent.
Now, a new article in Ecography by Geoffrey M. While and Tobias Uller (2014) conducted a phylogenetically controlled meta-analysis of breeding phenology of frogs, toads and salamanders to examine the extent of variation in amphibian breeding phenology in response to global climate change. They show that there is strong geographic variation in response to global climate change, with species at higher latitudes exhibiting a more pronounced shift to earlier breeding than those at lower latitudes. The analyses suggest that this latitude effect is a result of both the increased temperature (but not precipitation) at higher latitudes as well as a greater responsiveness by northern populations of amphibians to this change in temperature. The authors suggest that these effects should reinforce any direct effect of increasing warming at higher latitudes on breeding phenology. In contrast, they found very little contribution from other location factors or species traits. There was no evidence for a phylogenetic signal on advancing breeding phenology or responsiveness to temperature, suggesting that the amphibians that have been studied to date respond similarly to global warming.

Citation

Monday, May 19, 2014

The phylogeny of softshell turtles and the giant Shanghai softshell turtle, Rafetus swinhoei

The softshell turtles of the family Trionychidae have highly derived morphology evolved to adapt the turtles to an almost entirely aquatic environment. These adaptations include a smooth leathery skin covering with a reduced bony shell, a flattened body shape, and heavily webbed toes. Thirty-one species in 13 genera are distributed in Africa, Asia (including New Guinea), the Mediterranean, and North America. The fossil record supports the family’s former presence in Australia, Europe, and South America. Trionychid phylogenetic relationships are a fairly well resolved and robust molecular phylogeny of trionychids has been established. And, species boundaries within a number of widely distributed species or species complexes have been clarified. However, to date the taxonomic status of the critically endangered Shanghai softshell turtle, Rafetus swinhoei, is still a matter of debate. Ranked as one of the 100 most endangered species (only four live individuals of this species are known, two in Vietnam and two in China). Historically, this species had a large distribution range, including the Yellow River, Yangtze River, and their tributaries in China and the Red River system, as well as Ma River and associated wetlands in Vietnam. Previous molecular and morphological comparisons suggested that this is a single species but more recent work produced radically different results, and described populations in Vietnam as a new species, R. vietnamensis. A subsequent study shed doubt on this view by highlighting sources of potential errors. Despite this, it is likely that populations from Vietnam and China constitute independent evolutionary lineages given the distance and river systems separating them.

To test this hypothesis, Minh Le and colleagues analyzed data from two mitochondrial loci (cytochrome b and ND4) and one nuclear intron (R35) for all trionychid turtle species, except Pelochelys signifera, and for all known populations of Rafetus swinhoei in Vietnam and one from China. Phylogenetic analyses using three methods (maximum parsimony, maximum likelihood, and Bayesian inference) produce a well resolved and strongly supported phylogeny. The results the time-calibration and biogeographic optimization analyses show trionychid dispersed out of Asia between 45 and 49 million years ago in the Eocene. Interestingly, the accelerated rates of diversification and dispersal within the family correspond surprisingly well to global warming periods between the mid Paleocene and the early Oligocene and from the end of the Oligocene to the mid Miocene. The study also indicates that there is no significant genetic divergence among monophyletic populations of Rafetus swinhoei, and that previous taxonomic revision of this species is unwarranted.

Citation

Le, M., Duong, H. T., Dinh, L. D., Nguyen, T. Q., Pritchard, P. C., & McCormack, T. (2014). A phylogeny of softshell turtles (Testudines: Trionychidae) with reference to the taxonomic status of the critically endangered, giant softshell turtle, Rafetus swinhoei. Organisms Diversity & Evolution, 1-15.

A new horned lizard from Guerrero, Mexico

Phrynosoma sherbrookei. Photographer unknown
The journal Herpetological reports a new species of horned lizard in the genus Phrynosoma from southwest México. Body size, tail length, and scale texture and layout distinguish the new species, Phrynosoma sherbrookei. The new species is named after Wade Sherbrook, who has studied horned lizard behavior, ecology and systematics for many years.

There are 16 recognized horned lizard species, ranging from Canada to Guatemala. Only four species have been found south of México's trans-volcanic belt. These distinctive reptiles have a dorsum covered with spiny scales and bony horns on their heads. To avoid predators, they rely on camouflage and an ability to puff out their body. Some species squirt blood by rupturing capillaries surrounding their eyes when attacked by a canid predator. The blood contains formic acid, sequestered by the lizards from the ants they feed on. They are adapt to dry habitats, collecting rainwater by using their dorsal surface to channel water over their back and into their mouth. Some species are live bearing while other populations of the same species lay eggs.

In Guerrero, México, 14 lizards from the Sierra Madre del Sur were found to be an unrecognized species. Adrián Nieto-Montes de Oca and colleagues analyzed DNA from these specimens to support their proposal of a new species. They also generated a phylogenetic tree depicting the evolution of the horned lizards.

The new species can be distinguished from all other Phrynosoma by the possession of a unique combination of morphological characteristics. The molecular genetic data include three fragments of the mitochondrial genome and six nuclear genes (2419 and 3909 base pairs in total, respectively) for 31 samples belonging to the 16 previously recognized species of Phrynosoma and the new species

Phrynosoma sherbrookei is strongly supported in maximum likelihood analyses of both the concatenated mitochondrial and nuclear data as a monophyletic, distinct evolutionary lineage sister to, and moderately divergent from, P. taurus, and highly divergent from all of the other species of Phrynosoma. A Bayesian species tree analysis also strongly supports the monophyly of the Brevicauda clade, and a sister relationship between P. taurus and the new species.

Phrynosoma sherbrookei seems to live in a small area and may benefit from protection until researchers can learn more about the population.


Citation
Adrián Nieto-Montes de Oca, Diego Arenas-Moreno, Elizabeth Beltrán-Sánchez, and Adam D. Leaché (2014) A New Species of Horned Lizard (Genus Phrynosoma) from Guerrero, México, with an updated multilocus phylogeny. Herpetologica 70: 241-257.

Saturday, May 10, 2014

Four recently described colubroid snakes

2014 has been predicted to be a big year for new species of reptiles. These four reticently described species support that claim.
Siphlophis ayauma sp. nov
 Siphlophis ayauma sp. nov. was recently described by Sheehy and colleagues (2014) from the Amazonian slopes of the Ecuadorian Andes, in the provinces of Azuay, Tungurahua, and Zamora Chinchipe. This is the third species of Siphlophis known from Ecuador and the seventh species in the genus. Siphlophis ayauma has been found on the Amazon versant of the Andes Mountains of Ecuador from 1250 to 2200 m elevation in the Montane. Lower Montane, and upper Foothill Evergreen vegetation zones. Given its distribution, the species will very likely also be found in Peru. The female holotype was found active on forest floor vegetation during a rainy night.

Philodryas amaru sp. nov.
Philodryas amaru sp. nov. Zaher et al. (2014) is from the highlands of southern Ecuador The new species resembles Philodryas simonsii in color pattern but they differ in their  hemipenial morphology. The three other trans-Andean members of the genus (Philodryas simonsii, Philodryas chamissonis, and Philodryas tachymenoides), along with the new species, compose a probably monophyletic group that may be characterized by the presence of ungrooved postdiastemal teeth in the maxilla. Unlike most species of the genus Philodryas, the new species shows a restricted distribution, apparently restricted to a small region of high-altitude (3150–4450 m) grasslands in the southern Andes of Ecuador.

Opisthotropis durandi sp. nov.
Opisthotropis durandi sp. nov. Teyni et al. (2014) is based upon two specimens, collected in a karst formation of northern Louangphabang (or Luang Prabang) Province, North Laos. They differ from all other known Opisthotropis in morphology. It represents the first confirmed record of a species of Opisthotropis sensu stricto from Laos and it is the 108th snake species currently recorded from the Lao People’s Democratic Republic. This new aquatic snake was lying under a half-immersed rock at the bottom of a small waterfall in the course of a fast-running forest stream.  It is interesting to note that the local vernacular name of this snake is Ngou Koung or Ngou Kung, meaning “shrimp snake,” and shrimp were observed at the collection site, but its diet remains undocumented.

Rhabdophis guangdongensis sp. nov.
Rhabdophis guangdongensis sp. nov. Zhu et al (2014) was described from Guangdong Province, China. It is both genetically and morphological distinct, having a small body size; 20 maxillary teeth, with posterior enlargedn fangs that are not separated by diastemata and other traits. The description of this  species brings the number of described Rhabdophis to 21 and represents the tenth known Rhabdophis species in China.

Citations
Sheehy, C. M., Yánez-Muñoz, M. H., Valencia, J. H., & Smith, E. N. (2014). A New Species of Siphlophis (Serpentes: Dipsadidae: Xenodontinae) from the Eastern Andean Slopes of Ecuador. South American Journal of Herpetology, 9(1), 30-45.

Teyni, A., Lottier, A., David, P., Nguyen, T. Q., & Vogel, G. (2014). A new species of the genus Opisthotropis Günther, 1872 from northern Laos (Squamata: Natricidae). Zootaxa, 3774(2), 165-182.

Zaher, H., Arredondo, J. C., Valencia, J. H., Arbeláez, E., Rodrigues, M. T., & Altamirano-Benavides, M. (2014). A new Andean species of Philodryas (Dipsadidae, Xenodontinae) from Ecuador. Zootaxa, 3785(3), 469-480.

Zhu, G. X., Wang, Y. Y., Takeuchi, H., & Zhao, E. (2014). A new species of the genus Rhabdophis Fitzinger, 1843 (Squamata: Colubridae) from Guangdong Province, southern China. Zootaxa, 3765(5), 469-480.

Saturday, May 3, 2014

New Book: Snakes of the World: A Catalogue of Living and Extinct Species, is now available

Snakes of the World: A Catalogue of Living and Extinct Species. 2014. Van Wallach, Kenneth L. Williams, Jeff Boundy. CRC Press, Boca Rattan, FL. 1237 pp.

This volume  will be required reading for anyone seriously interested in snake systematics and diversity. It contains a checklist to all living and fossil snakes described between 1758 and 2012. These number 3,509 living and 274 extinct species allocated to 539 living and 112 extinct genera. Also included are 54 genera and 302 species that are dubious or invalid. Thus, book in recognizes 705 genera and 4,085 species.
The checklist is organized by genera with species alphabetically organized for ease of reference. The species accounts include: data on type specimens and type localities; a lists all subspecies, synonyms and proposed  names;  distribution of species by country and province, and geological time spans for fossil species; a complete summary of the systematic snake literature. It also provides a list of  references for each country. The literature cited  covers more than 200 pages.

In 2013 there were an additional 22 species of snakes described, and at least four new species have already been described in 2014. There have also been some major changes in higher level systematics within the past two years. Despite these updates, this is a indispensable volume for anyone working on snakes.

Thursday, May 1, 2014

Amphibians, climate change & habitat loss


Cascades frogs, found only at high elevations in three states, will face a hard future
where trout dominate high mountain lakes and climate change dries up many of the shallower
waterways such amphibians have been using. Photo Credit: M Ryan/U of Washington
A warming climate, however, will dry up some of the places where amphibians and their young have found refuge. Researchers in the May 1 issue of Frontiers in Ecology and the Environment write about this challenge and a novel combination of tools that could help land managers, biologists, fishing enthusiasts and other citizens weigh where amphibians are in the most need of help and guide plans for possible fish removals from selected lakes.

"Amphibians in the West's high-mountain areas find themselves in a vice, caught between climate-induced habitat loss and predation from introduced fish," said Maureen Ryan, a University of Washington postdoctoral researcher in environmental and forest sciences, a Simon Fraser University research associate and lead author of the paper.

Among the tools that could prove useful is a hydrologic model, currently used to project river flows, that can be applied to wetlands as a way to evaluate the effects of projected climate change. New remote-sensing techniques, using what's called object-based image analysis, allow managers to use existing aerial and satellite imagery to map wetlands in remote and previously unsurveyed regions.

Along with biological survey data these tools "can be used to identify regions where native wetland animals are most at risk of the combined effects of climate change and fish. In these regions, fish removal from strategic sites can be used to restore resilience to a landscape where inaction might lead to tipping points of species loss," writes Ryan and her co-authors Wendy Palen of Simon Fraser University, Michael Adams of the U.S. Geological Survey and Regina Rochefort of the North Cascades National Park.

The work was funded by the Department of the Interior's Northwest Climate Science Center, the David H. Smith Conservation Research Fellowship Program and the U.S. Fish and Wildlife Service's Pacific Northwest Landscape Conservation Cooperative.

In some parts of the West, programs of fish removal are already in place. Jack Oelfke, a manager at North Cascades National Park in Washington state says he watched long-toed salamanders, northwestern salamanders and tailed frogs return to lakes that his crews cleared of introduced trout. Fish stocking was halted in the park in 2007 after the park and Washington state completed an extensive environmental impact statement. The park began trout removal at eight lakes in 2009.

When considering removing fish, Ryan said human uses such as fishing are a part of the discussion. For the North Cascades National Park, for example, several high-lakes fisheries groups were involved.
"People often ask me what we can do about amphibian declines," said co-author Adams. "Fish removal is something that we know will help, but is hard to do and not always popular, so we need to be smart about it. This project provides a tool that can help target fish removal to places where it will do the most good for amphibians."

In some places, if a lake is no longer artificially stocked with fish, the trout will naturally disappear. Non-native fish also can be removed using a variety of techniques including gill nets or piscicides like the organic compound rotenone, which is extracted from plants.

As glaciers receded at the end of the last ice age they left behind thousands of isolated high mountain lakes and ponds devoid of fish. The bodies of water range in size from many acres, large enough to sail a boat on is how Ryan describes them, to ones smaller than your living room.

For centuries frogs, salamanders and other aquatic species flourished in these high elevation habitats where food was plentiful and their eggs and young were relatively safe from predators. In the late 1800s things started to change when trout were brought to mountain lakes and ponds in the American West by settlers looking for recreational fishing opportunities. Stocking intensified after World War II with millions of fish being dropped from aircraft by agency wildlife managers. Today 95 percent of the large mountain lakes have trout.

At risk are species such as the Cascades frog. Found only at high elevations in Washington, Oregon and California, Cascades frogs can live for 20 or more years, can survive under 30 feet of snow and, during the mating season, the males make chuckling sounds.

"We hope newly developed wetland modeling tools can improve climate adaptation action plans so ecosystems can maintain their resilience in the face of a changing climate," Ryan said.

Citation
Maureen E Ryan, Wendy J Palen, Michael J Adams, and Regina M Rochefort 2014. Amphibians in the climate vice: loss and restoration of resilience of montane wetland ecosystems in the western US. Frontiers in Ecology and the Environment 12: 232–240.http://dx.doi.org/10.1890/130145