Tuesday, April 3, 2012

Artificial Snake Hibernaculum A Succsess

Rob Carmichael, curator of the Lake Forest Wildlife Discovery Center, holds several brown snakes that spent the winter in a wine chiller in the center. The snakes were released Monday in Illinois Sate Beach Park in Zion. Michael Tercah/Chicago Tribune
The Chicago Tribune is carrying the following story.

After spending most of the winter curled up in a 6-foot-tall wine chiller in a Lake Forest wildlife center, scores of squirming reptiles were set free Monday and took up residence in new digs.

Beneath a sunny sky with temperatures hovering near a snake-friendly 50 degrees, Rob Carmichael placed handfuls of 4- to 10-inch long brown and garter snakes into a newly crafted outdoor den at Illinois Beach State Park.

There were 82 in all, including one western fox snake, some of them outfitted with microchips so their movements can be tracked.

“We hope these snakes will recognize this as their new home,” said Carmichael, director of the Lake Forest Wildlife Discovery Center, which hosted them for the last few months in the donated wine chiller.

Saturday, March 31, 2012

The Side-Blotched Lizard & A Warming Climate

A side-blotched lizard, Pima Co., AZ, JCM
Side-blotched lizards of the genus Uta are perhaps the most abundant and most frequently seen lizards in western North American deserts. Males are usually larger than females and have brightly colored throats that are used to signal other lizards. They mature rapidly and reproduce at young age. Many fall prey to a variety of birds, mammals, and other reptile, thus in some populations few live longer than a year. Mature females regularly lay two clutches (and in some years possibly three), yearlings frequently lay only one clutch unless environmental conditions are especially favorable.

Clark & Zani (2012) used the side-blotched lizard to examine the impact of climate change, hypothsizing that temperate ectotherms, especially those at higher latitudes, would benefit from climate warming. Most previous studies on the effects of climate change use a model of uniform annual change, which assumes that temperature increases are symmetric on diurnal or seasonal time scales. In this study, Clark & Zani simulated observed trends in the asymmetric alteration of diurnal temperature range by increasing night-time temperatures experienced by female lizards during their ovarian cycle as well as by the resulting eggs during their incubation. They found that higher night-time temperatures during the ovarian cycle increased the probability of reproductive success and decreased the duration of the reproductive cycle, but did not affect embryo stage or size at oviposition, clutch size, egg mass or relative clutch mass. However, higher incubation temperatures increased hatchling size and decreased incubation period but had no effect on incubation success. Subsequent hatchlings were more likely to survive winter if they hatched earlier, but the sample size of hatchlings was relatively small. Their results suggest higher night-time temperatures affect the rates of processes and that certain aspects of life history are less directly temperature dependent. Thus climate warming is likely to increase the rate of development as well as advance reproductive phenology, and the authors predict that warmer nights during the breeding season will increase reproductive output as well as subsequent survival in many temperate ectotherms, both of which should have positive fitness effects.

Citation
Clarke DN, and Zani PA. 2012. Effects of night-time warming on temperate ectotherm reproduction: potential fitness benefits of climate change for side-blotched lizards, Journal of Experimental Biology 215:1117-1127. doi:10.1242/jeb065359

Crocodilian Bite Force

University of Florida Photo
In Greg Erickson's lab at Florida State University, crocodiles and alligators rule. Skeletal snouts and toothy grins adorn window ledges and tables -- all donated specimens that are scrutinized by researchers and students alike.

Lately, Erickson, a Florida State biology professor, and his colleagues have been pondering a particularly painful-sounding question: How hard do alligators and crocodiles bite?

The answer is a bite force value of 3,700 pounds for a 17-foot saltwater crocodile (as well as tooth pressures of 350,000 pounds per square inch). That's the highest bite force ever recorded -- beating a 2,980-pound value for a 13-foot wild American alligator Erickson's lab measured in 2005. They estimate that the largest extinct crocodilians, 35- to 40-foot animals, bit at forces as high as 23,100 pounds.

Erickson, along with several colleagues, including Florida State biology professors Scott Steppan and Brian Inouye, and graduate student Paul Gignac, reported their findings in the journal PLoS One.

Funded by the National Geographic Society and the FSU College of Arts and Sciences, their study looks at the bite force and tooth pressure of every single species of crocodilian. It took more than a decade to complete and required a wily team of croc handlers and statisticians, as well as an army of undergraduate and graduate students. Erickson describes crocodilian bite-force testing as being a bit like dragon slaying by committee.

"Our work required a team effort," he said.

As a result of the study, Erickson and his team have a new understanding on how these animals became so successful and a better understanding about the remarkable biology of living crocodiles and alligators. They've also developed new methods for testing bite forces.

The data contributes to analyzing performance in animals from the past and provides unprecedented insights on evolution and statistically informed models about other reptiles such as dinosaurs.

The study's findings are so unique that Erickson's team has been contacted by editors at the "Guinness Book of World Records" inquiring about the data.

Over the 11 years that his current study took place in both the United States and Australia, Erickson and his team roped 83 adult alligators and crocodiles, strapped them down, placed a bite-force device between their back teeth and recorded the bite force. An engineering calculation was then used to estimate the force generated simultaneously by the teeth nearest the front of the jaws. The team molded the teeth with dentist's dental putty, made casts and figured out the contact areas.

Talk about dangerous work.

As Erickson describes it: "I have to admit, the first time I placed our meter into the maw of an adult crocodile, I was nervous. It was all over in the blink of an eye. When it struck, it nearly wrested my grip from the handle. The noise of the jaws coming together was like a gunshot. The power of the animal was astounding, and the violence of the event frightening."

Overall, the researchers looked at crocodilians both mundane and exotic, from American alligators to 17-foot Australian saltwater crocodiles and the Indian gharial. Among the world's most successful predatory reptiles, these creatures have been "guardians of the water-land interface for over 85 million years," Erickson said.

But just how they were able to occupy and dominate ecological niches for so long is a mystery.

Erickson and his team knew that the reptiles evolved into different sizes, from 3-footers to 40-footers, and they showed concurrent major changes in their jaw shape and tooth form, while their body form remained largely unchanged.

"We set out to answer how this anatomical variance related to their ability to generate bite force and pressures for feeding in the different forms and thus how they have been so successful," Erickson said. "The bite force over the contact area is the pressure, which is more pertinent to feeding performance than bite force. Ultimately, it tells us just what they were doing with those prodigious bite forces."

And, he added, gators and crocs have comparable maximal bite-force capacity when measured pound for pound. They basically all have the same musculoskeletal design, just different snouts and teeth.

"It is analogous to putting different attachments on a weed eater -- grass cutter, brush cutter, tree trimmer, they all have the same type of engine," Erickson said. "There are bigger and smaller engines, with higher and lower horsepower, but they have the same attachments."

His research team is already using the study's data to explore bite-force and tooth-pressure performance in fossil forms. The team is building the world's most sophisticated models for extinct crocodiles and dinosaurs based on the findings, as well as continuing to study the significance of croc snout form.

As for modern-day crocs and gators, well, there's little doubt that they are truly the world's bone-crushing champions. Just remember that old Floridian maxim: Always maintain a healthy distance between yourself and the nearest gator.

"If you can bench-press a pickup truck, then you can escape a croc's jaws," Erickson warned. "It is a one-way street between the teeth and stomach of a large croc."

Gregory M. Erickson, Paul M. Gignac, Scott J. Steppan, A. Kristopher Lappin, Kent A. Vliet, John D. Brueggen, Brian D. Inouye, David Kledzik, Grahame J. W. Webb. Insights into the Ecology and Evolutionary Success of Crocodilians Revealed through Bite-Force and Tooth-Pressure Experimentation. PLoS ONE, 2012; 7 (3): e31781 DOI: 10.1371/journal.pone.0031781

Friday, March 30, 2012

Where Common Snakes are Rare and Rare Snakes are Common - On the Abundance of Tropical Snakes

Above: the arboreal cat snake, Boiga jaspidea; below the cryptozoic Gongylosoma baliodeirus. Photographed in the Danum Valley, Sabah, Malaysia.


Hans Breuer's post on Herp Nation's web site, Herping in the Tropics - Ecstasy or Nightmare?, brought back memories from another lifetime. In 1989 I spent a couple of months collecting data and specimens in Sabah's Danum Valley, an area of more than 400 sq km of lowland and hill dipterocarp forest that ranges in elevation from 150 to 1093 m asl. It was one of four trips to the Danum Valley run by the Field Museum to investigate the community ecology of the herpetofauna in Southeast Asia. From those four trips we put together a field guide and key to the snakes of the area (Murphy et al. 1994).

The article contained a bar graph of the 36 species found in Danum over 166 days of field work and how many of each species were collected. The graph is shown below, the photo insert is the species found most often, Pseudorabdion collaris, a small fossorial snake encountered while turning cover or raking leaf litter. 

Snakes are not easy to find in the tropics. The 166 days of field work produced 161 specimens (0.969 snakes per day). This was accomplished with three to four people working in the field a minimum of 6 hours per day (so at least 18 hours of effort per day to produce just less than one snake per day).

This experience is not unusual. William Beebe (1946) published the results of 36 months of field work at Kartabo, Guyana in one square mile of lowland tropical forest. He collected 425 snakes representing 52 species over 1080 days, or 0.39 snakes per day.

Dunn (1949) described a collection of snakes made by H.C. Clark in Panama. Dunn described 10,690 snakes representing collected over 13 years (4745 days)at four locations (the number of species varied between 40 and 60). The result was 2.25 snakes per day but this was a commercial venture involving many people.

Duellman (1978) reported on 1440 days of field work at Santa Cecilia, Ecuador and four nearby localities. His data show 564 specimens of 51 species, or about 0.38 snakes per day.

Today, the best answer as to why tropical snakes are difficult to find and when you do find them, rarely do you find a single species to be particularly abundant, seems to be exactly what Breuer concluded, the vast number number of hiding places in the tropics combined with the cryptic nature of snakes makes common snakes rare and rare snakes common. It also suggests, the diversity of snakes has been greatly under estimated and much remains to be discovered.

Literature
Beebe, W. 1946. Field notes on the snakes of Katabo, British Guiana, and Caripito, Venezuela. Zoologica 31, 11-51.

Duellman, WE. 1978. The biology of an equatorial herpetofauna in Amazonian Ecuador. University of Kansas, Miscellaneous Publications (65), 1-352.

Dunn, ER. 1949. Relative abundance of some Panamanian snakes. Ecology 30, 39-57.

Murphy JC, Voris HK, Karns, DK. 1994, A field guide and key to the snakes of the Danum Valley, a Bornean  tropical forest ecosystem. Bulletin of the Chicago Herpetological Society 29(7):133-151.

Wednesday, March 28, 2012

The Rediscover of Cardioglossa cyaneospila

SAN FRANCISCO (March 27, 2012) – Herpetologists from the California Academy of Sciences and University of Texas at El Paso discovered a single specimen of the Bururi long-fingered frog (Cardioglossa cyaneospila) during a research expedition to Burundi in December 2011. The frog was last seen by scientists in 1949 and was feared to be extinct after decades of turmoil in the tiny East African nation.

For biologists studying the evolution and distribution of life in Africa, Burundi sits at an intriguing geographic crossroads since it borders the vast Congo River Basin, the Great Rift Valley, and the world’s second largest freshwater lake, Lake Tanganyika. Many of the species in its high-elevation forests may be closely related to plants and animals found in Cameroon’s mountains, suggesting that at some point in the past, a cooler climate may have allowed the forests to become contiguous.

Previous knowledge of Burundi’s wildlife came from scientific surveys conducted in the mid-20th century, when the nation was under Belgian administration. But its history since then has been one of political unrest, population growth, and habitat loss. Today, approximately 10 million people occupy an area the size of Massachusetts, giving Burundi one of the highest population densities in Africa.

Academy curator David Blackburn joined his colleague Eli Greenbaum, professor at the University of Texas at El Paso, on the 2011 expedition with the goal of finding Cardioglossa cyaneospila, as well as other amphibians and reptiles first described 60 years ago. To their pleasant surprise, the habitats of the Bururi Forest Reserve in the southwest part of the country were still relatively intact, with populations of rare forest birds and chimpanzees present.

With little knowledge to go on except a hunch that C. cyaneospila would make a call like its possible close relatives in Cameroon, Blackburn finally found a single specimen on his fifth night in the forest.

“I thought I heard the call and walked toward it, then waited,” said Blackburn. “In a tremendous stroke of luck, I casually moved aside some grass and the frog was just sitting there on a log. I heard multiple calls over the next few nights, indicating a healthy population of the species, but I was only able to find this one specimen.”

The Bururi long-fingered frog is about 1.5 inches long, with a black and bluish-gray coloration. The males are notable for one extra-long finger on each foot, analogous to the “ring finger” in humans, whose purpose is unknown. Its closest relatives live in the mountains of Cameroon, more than 1,400 miles away.

The lone specimen collected, which now resides in the Academy’s herpetology collection, can be used for DNA studies to determine how long the Cardioglossa species from Burundi and Cameroon have been genetically isolated from one another. The results will shed light on Africa’s historical climate conditions, a topic that has far-reaching implications for understanding the evolution of life in the continent that gave rise to our own species.

In addition to locating the Bururi long-fingered frog, Blackburn and Greenbaum also documented dozens of other amphibians in Burundi, many of which had never before been recorded in the country. The team also discovered some species that may be new to science.

“Eventually, we will use the data from our expedition to update the IUCN conservation assessment for amphibians of Burundi,” said Greenbaum. “Because Burundi is poorly explored, we’ve probably doubled the number of amphibian species known from the country. Once we demonstrate that Burundi contains rare and endemic species, we can work with the local community to make a strong case for preserving their remaining natural habitats.”

Tuesday, March 27, 2012

Suzio Report March 18

Howdy Herpers, 
Sunday, March 18 brought upon us the weather conditions that are ideal for herping: 8 degrees C, rain and sleet, and howling winds. John Slone and Marty Feldner joined me for the arctic blast, and we had a blast in the process. There were others who were supposed to join us, but at the first sign of bad weather, they starting mewing like baby bunnies going down a Gila Monsters gullet. "We're AFRAID, Roger. We might get all wet. Meow........."  So, three manly men arrived in the teeth of a hail storm, and the first stop was a check on AD1. And from here, we can let the images tell the story. 

Image 1: The scene at the lower apron of AD1. Note how the globe mallow this snake is under is dripping  wet.

Pic 2: Mallow moved aside. Note the head on this adult male atrox. Rain harvesting posture. 
Pic 3: The first female atrox that I've seen at AD1 in over 3 years. VERY cool! She was likely drinking off the upper edge of the crevice. 

Pic 4: We find this atrox under the leaning boulder that we call "Kimmie Rock." This boulder is ~2m west of the almighty crevice of AD7. Hopeful that he might be stacked on a female, we hauled him out. 


No female, and apparently, too many years of chawing Skoal had done some damage to the lower left lip.
Pic 5: Closeup of lip, and good left eye.   

Pic 6: Closeup of right eye. I got the impression that this poor dude was blind in this eye. Any Vets care to venture an opinion? 

We also had a tortoise completely out, head nuzzled against the edge of a prickly pear. It is possible she was drinking drops off one of the pads. We drove through a sleet storm to another den in the Durham Mountains, where we found one atrox out cruising in the sleet!

That's all that's fit to spit. Until the next time, roger



Monday, March 26, 2012

Titanoboa Documentry Hype

The Smithsonian Channel will be showing a documentary on the fossil boid Titanoboa. The trailers and advanced promotional material can be found here.
BY PAT SUMMERS
NEWJERSEYNEWSROOM.COM

“Titanoboa” – the name says it all: giant squeezing snake. In Greek mythology, “Titans” were primordial giant gods, and the word has come to mean any person or thing of enormous size, strength, power, influence. Like a 48-foot long boa constrictor weighing more than a ton, with a manhole-size diameter.

New York’s Grand Central Station hosted this beast -- in replica – for two days this week while it was in transit to Washington, DC. By the time you read this, the model of Titanoboa (“ty-tan-uh-BOH’-ah,” according to Yahoo.com) may be ensconced at the Smithsonian’s National Museum of Natural History.

Yes, it was all a promotion – a darn big one – for a museum exhibit and a TV documentary.

However, this colossal reptile really did live on earth – 60 million years ago. It swam and slithered its 2,500 pound way around when the world’s first known rain forest emerged and dinosaurs no longer ruled, LiveScience.com reports.

Discovered by scientists in an open-pit coal mine in Columbia in 2005, it was the largest snake ever discovered, as Thirteen.org succinctly put it. The paleontologists who found it also named it, publishing their discovery in 2009.

People who saw the scientifically accurate model in New York dismissed their chances against such a snake, but they needn’t have worried. Humans to Titanoboa might equate with ants to humans: not even in the picture.

A Smithsonian video online pits the snake against a T-Rex, even thought the two “killer carnivores” actually lived in different times and on separate continents. (The winner wasn’t predicted, only the likely attack modes of each animal.)

The Titanoboa killed by constriction, then swallowed its prey whole. One estimate was that it squeezed with a crushing 400 pounds per square inch of pressure – equivalent to being crushed with the weight of three Eiffel Towers.

“Big” was the name of the game for many prehistoric animals, and the reasons that was so are interestingly spelled out in CSMonitor.com. Predictably, Titanoboa wins in comparison to a modern snake, such as the world’s longest reticulate python -- little more than half the length of its ancient relative. Reputed to be the world’s heaviest snake, the green anaconda is only about a tenth of the Titanoboa’s weight.

The Smithsonian exhibition featuring the Titanoboa will run from March 30-January 6, 2013. Focusing on the giant reptile’s discovery and reconstruction processes, Smithsonian Channel premieres a documentary, “Titanoboa: Monster Snake,” on April 1. No foolin’.

Thursday, March 22, 2012

Lithobates (Rana) yavapaiensis Gets Protected Land

Photo Credit: Dennis Caldwell.
Arizona Daily Star, March 21, 2012

10K acres set aside for threatened frog. Areas near Rosemont not included due to absence of breeding

By Tony Davis
The federal government will designate more than 10,000 acres in Arizona and New Mexico as prime habitat for the threatened Chiricahua leopard frog.

More than a dozen streams and many livestock watering tanks across Southern and Central Arizona were picked by the U.S. Fish and Wildlife Service as critical habitat for the frog, a threatened species.

The Las Cienegas National Conservation Area, Florida Canyon in the Santa Rita Mountains, Peña Blanca Lake near Nogales, Sycamore Canyon in the Atascosa Mountains and Ramsey and Brown canyons in the Huachuca Mountains are among the critical habitat sites.

But other areas near the proposed Rosemont Mine site in the Santa Ritas that have had leopard frogs were left out because the frogs aren't known to breed there now - largely because there's less water there than there was several decades ago.

The decision means one less legal issue for the mine, since lands designated critical habitat can't be destroyed or seriously modified by projects that need U.S. permits.

Last year, mine opponents with the Center for Biological Diversity and Pima County recommended six livestock watering tank sites on Forest Service and private land in the mine area as prime frog habitat. The Wildlife Service rejected them in its decision this week and chose six other tanks farther away, within two or three miles of the mine site. In recent years, such tanks have become key areas for the leopard frog.

Mary Richardson, a wildlife service supervisory biologist, said the agency determined the Rosemont sites didn't meet critical habitat criteria. First, there is no indication that frogs breed there. Leopard frogs can travel as far as five miles, spending time in one area and breeding in another.

Frog researchers Philip Rosen, of the University of Arizona, and Dennis Caldwell, a private researcher, said the Rosemont-area sites are worth protecting, and that breeding could be restored there. But they agreed that the areas don't meet the feds' critical-habitat standards without breeding populations.

Michael Robinson of the Center for Biological Diversity said that overall, the group is pleased by the habitat decision. But it was disappointed that the Rosemont-area tanks weren't picked.

Robinson said the mine could obliterate frogs on its land and could destroy their ability to survive nearby due to dust, toxic chemicals, blasting sounds and truck traffic.

Julia Fonseca, Pima County's environmental planning manager, wrote the Wildlife Service in 2011 that leopard frogs were reported as "abundant" in the Rosemont area in the 1970s by private biologists. While the surveyors didn't note whether they were Chiricahua or lowland leopard frogs, the Arizona Game and Fish Department concluded in the 1990s they were Chiricahua frogs.

Surveys by Rosemont Copper consulting firm Westland Resources found those frogs in the six Rosemont-area water tank sites in a 2008 survey, but they weren't breeding.

Still, the frogs' presence throughout the Santa Ritas suggests the area contains a regional group of connected populations whose habitat needs protection, said Fonseca and Robinson.

Rosemont Copper official Kathy Arnold said based on the company's surveys for frogs and other species, the Wildlife Service findings met Rosemont's expectations.

"Rosemont works with Arizona Game and Fish, U.S. Fish and Wildlife Service, the University of Arizona and the U.S. Forest Service, as do other ranches and property owners in the area," Arnold, Rosemont's vice president for environmental and regulatory affairs, added in a written statement.

"Contributions besides the survey work include providing water to habitat during dry periods, assisting with stormwater controls to control sediments entering ponds, and managing and providing access to habitat," she said.

Suzio Report, Winter 2012

Howdy Herpers, 03/21/12
So, where's Waldo these days? He's wherever you folk find him. 

My new duties with the THS have me so buried that I can't play where's Waldo any more. Perhaps the day will come when I have too much time on my hands again. When that happens, we'll play some more Waldo games. 

It was another one of those inglorious winters this year weather-wise. We had April weather in January and February, and January weather in March thus far. The herps under watch don't know whether to defecate or go blind. The Gila Monsters got jacked up early and split, but not before we got to see lots of burrow action. The atrox have yet to bask enmasse anyplace I've been. Four is the most that I've seen out. And I have only encountered one snake on the road thus far--a DOR atrox

But the tortoises have been putting on quite a show for us. At one point, we had 8 visible on our little hill. This ties a record set back in 2001 of the most tortoises viewed before the first day of spring on that hill.
Without further adieu, we'll let the images tell the story.

Image 1: The Lazy M Gila Monster, Hill 97. This image was taken on 2 January. The dude cleared out in early February. I hope so see him again next November.
Image 2: A small female tortoise out basking on 11 February. Note the green lips, a sign of early feeding.  
Image 3: Pair of male atrox out basking on the shelf of the den we call AD Zero. This marginal image is the best I've taken of basking this spring. 11 February, 2012  
Image 4: A nearly impossible image to get, a pair of Gila Monsters in deep in our communal den. At one point, we had three monsters visible this spring. 4 February 2012 (Hans-Werner Herrmann).  
Images 5 - 7: A sequence of the tortoise we called "Slone's Tortoise." On 29 January, she is edging toward the apron of the burrow. On 29 January, she is out, but has not fed yet. On 18 February, she has obviously been browsing. 

Image 8: Female Gila Monster number 19, a new monster for our study. She was found out moving around on 4 March, but one of the students of Kevin Bonine's herp class. 
Image 9: The "Twin Saguaro" old male tortoise out browsing on 22 February. Sights like this are to die for!  
That's all that's fit to spit. I expect BIG things in the days ahead.

Yours, roger

Wednesday, March 21, 2012

Antivenom Kits for Use by the Public

The following story appear in the Times of India today, let’s hope the reference to venom really refers to anti-venom.

PUNE: The Pimpri-based Haffkine Bio-pharmaceutical Ltd, a state government undertaking, has developed an easy-to-use venom kit for reducing deaths caused due to snake bites, especially in rural areas.

The kit is useful for treating bites of four most poisonous snakes - the common cobra, Russel's viper, Common Krait (Manyar) and saw scaled viper (Ghonas/Furse).

Prakash Sabde, managing director of Haffkine Bio-pharmaceutical Ltd, said, "It is difficult to get treatment for snakebite in villages. This kit is easy to use and can be administered by a nurse or an attendant at government rural hospitals. The venom kit gives sufficient time for the victim to be rushed to a bigger hospital for treatment, if necessary. This increases chances of a patient's survival."


Manager and public relations officer Navnath Garje said, "The kit contains vials of venom that need to be injected after the bite. It also includes posters and a booklet containing instructions on how to use the kit and treat the patient besides giving answers to most common misconceptions about snakebites and its cure. The venom in the kit has a shelf life of four and a half years."

Garje said the company will hold discussions with the Pune branch of the Indian Medical Association for approaching doctors and creating awareness about the kit. They would also set up stalls in Konkan where snakebite cases are high.

Garje said that people in villages either go to quacks or use crude methods for treatment which results in loss of valuable time and eventually death. "It is necessary they get proper treatment on time."

Tuesday, March 20, 2012

Student Project on Lake Erie Water Snakes

Lake Erie Water Snakes, Nerodia sipiedon insularum
University of Cincinnati' s Lauren Flick, a 19-year-old, triple-major senior, will present findings at an upcoming regional conference on the first-ever use of a surgically implanted device to record the habits of snakes in their natural environment. This particular study holds promise in “keeping score” as Ohio’s Lake Erie water snake defends its native habitat against an invasive fish species.

Thanks to research by a University of Cincinnati undergraduate student and two team members, there’s a new tool that’s now been tested and found to work in continuously recording the habits of snakes.

This small-scale study is the first-ever use of Lotek Archival Tags (LATs) on snakes, since the LAT devices were originally developed for use in avian and fish species due to LATs’ ability to measure temperature and pressure – measuring pressure translates into altitude and depth.

UC’s Lauren Flick, a triple-major pursuing simultaneous undergraduate degrees in biology, psychology and criminal justice, will present the findings of the snapshot study, “Comparing the Effectiveness of Lotek Archival Tags (LATs) in a Behavioral Study of the Lake Erie Water Snake,” at the March 23-25 Midwest Ecology and Evolution Conference, a conference specifically for undergraduate and graduate student research that will draw representatives from regional schools.

Participating in the study with Flick were lead researcher Kristen Stanford, a doctoral student at Northern Illinois University and recovery plan coordinator for the Lake Erie water snake, and Lindsey Korfel, a student at Wittenberg University. Their research study was conducted during summer 2011 at Ohio State University’s Stone Laboratory located on Lake Erie.

The traditional manner for tracking snakes’ movements is primarily with a radio transmitter. In other words, a researcher would attach a location transmitter to a ground snake and then hope he or she could then stay or get within range over a period of time to visually determine its habits

What Flick, Stanford and Korfel did was to catch two female Lake Erie water snakes (LEWS) and arrange for the implantation of LATs. Importantly, the LATs record and store data on the snakes over time, such that it’s not necessary for a researcher to be within visual range of the snake. In fact, a researcher could leave the snake undisturbed in its natural habits and environment for days, even weeks, at a time when using a LAT. (During this study, the snakes were not harmed, and the LATs were removed at the end of the study.)

“This was proof of concept that use of LATs in reptiles is a viable research method,” said Flick, a resident of Cincinnati’s Green Hills community. “For a study like ours, it’s harder and less effective to rely solely on using the traditional radio transmitter on a water snake moving in the depths of the Great Lakes. And even when using the average transmitter with a ground snake, you have to stay within about 50 meters for the tracking technology to work. That kind of close tracking could also serve to disturb the very habits a researcher is hoping to observe.”

The Lake Erie Water Snake (LEWS), found only in the western Lake Erie waters of Ohio and Canada and only recently removed from the list of federally endangered and threatened species, is estimated to number more than 8,000 adults. Its population size had fallen to about 1,500 adults in the mid-1990s – very low because they were often killed by humans and because of loss or degradation of habitat on the shoreline or on the Lake Erie islands where they are native.

Explained Flick, “Basically, the islands and shorelines are an important part of the snakes’ habitat. They live on land and only forage in the water. Humans on the Lake Erie islands didn’t, for a long time, see value in having snakes around, even though we now know that these nonpoisonous snakes were and are a valuable part of the ecosystem.”

And while those numbers have recovered sufficiently to remove the species from the endangered status, it’s important to understand how the species is faring in terms of foraging, maintaining body temperature and finding appropriate mating, resting and hibernating environments because the LEWS are a major player in combating the invasive round gobi fish.

The round gobies, a bottom-dwelling species, are considered very harmful because they are voracious nest predators of many of Lake Erie’s native game fish and bottom-dwelling fish, and there are now estimated to be billions of the round gobies in Lake Erie. However, as it turns out, the native Lake Erie water snakes will eat round gobies.

And even though the student research was a snapshot involving just a pair of snakes, they found some intriguing results recorded by the LAT devices.

Said Flick, “Previous studies have estimated that the LEWS spend only 7 percent of the time foraging for food. The snakes that we studied actually spent 20-25 percent of the time foraging. One of the snakes even went out foraging at about midnight, which is unusual because the LEWS are not normally nocturnal.”

And since it’s estimated that 90 percent of the LEWS’ diet consists of round gobi fish, more time eating by the LEWS should translate into fewer round gobies.

The story is reprinted from an original story written by M. B. Reily and materials provided by University of Cincinnati.

Saturday, March 17, 2012

Natrix natrix cypriaca, Court Ruling

A Cyprus Mail story By Poly Pantelides reports that the European Court of Justice yesterday said Cyprus broke EU law by failing to protect Paralimni lake and the endangered native grass snake.

“We hope (the ruling) will lead to swift action to properly protect the highly threatened Paralimni Lake, home to this unique snake and also a key site for birds,” said BirdLife Cyprus’ executive director, Dr Clairie Papazoglou. “We also hope it will lead to the authorities taking their obligations to implement EU nature directives far more seriously,” Papazoglou added.

However, Hans-Jorg Wiedl the reptile expert who rediscovered the grass snake after it was thought to be extinct for 40 years and who has been lobbying authorities for years, thinks “it’s too late”.

“It will take a miracle to save the snakes,” said, Wiedl better known as Snake George. “It breaks my heart,” he said almost in tears.

The endangered nonvenomous grass snake, Natrix natrix cypriaca, sometimes called the water snake can be found in Paralimni Lake and the Xyliatos Dam.

However Cyprus had not originally included the lake in its list of sites of community importance (SCIs) as part of the Habitats Directive.

The island’s federation of environmental and ecological organisations complained to the European Commission in May 2006, and in March 2007 the Commission launched an infringement procedure against Cyprus, asking the government in a letter of formal notice to include the lake in the CSIs list.

Cyprus said it would do this before the end of 2007 but eventually claimed the Commission did not follow proper procedure, so in June 2008 the Commission issued a reasoned opinion asking Cyprus to comply with the Habitats Directive.

Although the Republic responded with a list of measures it was taking to protect the grass snake and Paralimni Lake, the Commission received complaints on property development of the northern part of the lake.

By 2009, Cyprus included Paralimni Lake in the CSIs, except for the northern part of the site.

The Commission argued that the lake was essential to the survival of the grass snake but failing to include parts of it could not ensure the snake’s protection and conservation.

Cyprus said the snake was only found in the southern and eastern parts of the lake.

Because development in the area took place after the Commission launched the infringement procedure, the Commission’s arguments on the effect development could have on the snakes could not be admitted, the court said.

The court, however, said that excavation works in the northern part of the lake did disturb the snake and Cyprus “did not put in a system of strict protection in place”.

Cyprus broke EU law by not including the entire Paralimni Lake in the CSIs, “tolerating activities which seriously compromise the ecological characteristics” of the lake, “by not having taken the protective measures necessary to maintain the population” of the grass snake, and “by failing to take measures “to establish and apply a system of strict protection for that species,” the court said.

If Cyprus fails to act, the Commission may give it one final written warning before sending the case back to court, imposing potentially hefty financial penalties including a daily penalty payment for each day until the infringement ends.

Adaptation to TTX by Snakes

A new study by University of Notre Dame biologist Michael Pfrender and a team of researchers from the University of Nevada, Reno; Utah State University; and the University of Virginia suggests that snakes from different regions of the world have evolved a similar, remarkable resistance to a deadly neurotoxin.

The finding, which appeared in the Proceedings of the National Academy of Sciences, greatly increases scientists’ understanding of the genetic basis of adaptation and is a model for understanding the limits to adaptation and the degree to which evolutionary responses are predictable.

Pfrender and colleagues found species of snakes in North, Central and South Americas and Asia that are able to feed on amphibians that secrete a deadly neurotoxic poison, tetrodotoxin or TTX. These snakes have similar mutations in a key sodium-channel gene that makes them highly resistant to TTX. These mutations prevent TTX from blocking the sodium channels in muscle, which would otherwise immobilize the snakes by paralyzing nervous and muscle tissue.

“The key finding is that adaptive evolution is constrained by the functional properties of the genes involved in these evolutionary responses,” Pfrender said. “While there are many possible mutations that can improve fitness, in this case resistance to the neurotoxin TTX, many of these mutations have a cost because they change the normal function of the genes. So, when we look at multiple species that have independently adapted to TTX, we see a very similar, and limited, set of mutations involved. The story is one of repeated evolutionary change that occurs through a limited set of changes at the molecular level.”

The study stems from Pfrender’s interest in understanding how organisms deal with environmental change through adaptive evolution.

“We would like to know what the underlying genetic mechanisms are, and what the limits are to these adaptive responses,” he said. “Ultimately, we would like to develop a predictive framework to gauge when natural populations will be able to evolve rapidly enough to persist in a changing environment and when the environmental change is too fast or too strong, leading to local extinction.”

An understanding of how organisms deal with environmental change is relevant to the major themes of Notre Dame’s Environmental Change Initiative and to the Eck Institute for Global Health, which examines disease resistance coupled with human health.

“Many organisms are exposed to toxic chemicals in their environment, and this system is a model for understanding how they cope with this challenge through evolutionary change,” Pfrender said. “A good example of the application of this knowledge is when we are trying to understand how parasites acquire drug resistance. How do they do it and what are the limits to this response? Can we create more effective drug strategies that capitalize on these functional constraints, making it more difficult for parasites to evolve resistance?”

Pfrender and the Utah State researchers plan to study more snake species and to expand their research to a number of other species, including insects that prey on the toxic eggs of salamanders. They also are examining other genes closely related to the sodium channel genes that are the focus of the PNAS study to expand their understanding of how adaptation occurs.


Citation
Chris R. Feldman, Edmund D. Brodie, Jr, Edmund D. Brodie III, and Michael E. Pfrender. 2012. Constraint shapes convergence in tetrodotoxin-resistant sodium channels of snakes. Proceedings of the National Academy of Sciences published online before print March 5, 2012, doi:10.1073/pnas.1113468109

The Aesculapian Snake In Central London

The following story was adopted from the West End Extra by Josh Loeb. The Aesculapian snake, Zamenis longissimus, is widely distributed in Europe, but rarely considered abundant and also appears to be declining in numbers. Several isolated populations occur around the edges of the range and are thought to be remnants of a wider distribution. Apart from its ecological role, it also has symbolic and cultural interest in Europe, and it is the snake depicted on the international medical symbol. A recent article in The London Naturalist describes an established a breeding colony on the fringes of Regent’s Park. Over time many have apparently been found in the capital, most of them thought to be unwanted pets released by their owners, but few if any have managed to survive for long periods in the cool and unfamiliar ­climate of central London, let alone breed. It is for this reason that Westminster’s colony of aesculapian snakes, which experts say thrive on the banks of the Regent’s Canal, is considered significant, although mystery surrounds how the creatures, native to the Balkans established a population in London. One theory is that snakes kept at a now defunct Inner London Education Authority facility for scientific experiments were released “on the quiet” in the 1980s. According to the paper, the feral population was first described in 1998 by a head keeper of reptiles in London Zoo. The article also states, “Several newly born snakes were found in the basement of a building around 30 metres from the embankment in 2010, and breeding in that year was also shown in 2011 with a young 2010 cohort snake being located. To this date this is the only example of a non-native snake species breeding successfully and forming populations in the wild in London and the UK as a whole.” Fragments of juvenile aesculapian snakes have also apparently been found in bird aviaries close to the canal. The snakes are believed to survive by feeding on rodents and possibly small birds.

Thursday, March 15, 2012

Undescribed Lithobates from New York & New Jersey

Hiding in Plain Sight: Rutgers Scientist Discovers New Frog Species in New York and New Jersey

In New York City – in the midst of some of the world’s tallest skyscrapers – and within view of the Statue of Liberty, scientists have found a new frog species.

While discovering new species in remote rainforests is common, finding this one in the ponds and marshes of Staten Island, mainland New York, and New Jersey was a big surprise to the scientists from Rutgers University, UCLA, UC Davis, and the University of Alabama who worked together to make the discovery .

The yet unnamed frog – which biologists historically mistook for a more widespread variety of the leopard frog -- may even extend into parts of Connecticut and extreme northeastern Pennsylvania. Researchers believe that these are likely the same leopard frogs that completely disappeared from Long Island and other parts of the area over the last few decades.

“It is very surprising for a new species like this to have been unrecognized in this area until now,” said Rutgers doctoral candidate and guest researcher at Brookhaven National Laboratory Jeremy Feinberg, who made the initial discovery. “Their naturally limited range coupled with recent unexplained disapperances from places like Long Island underscores the importance of this discovery and the value that conservation efforts might have in the long-term survival of this urban species."

In newly released research, available online in the journal Molecular Phylogenetics and Evolution, scientists used mitochondrial and nuclear DNA data to compare the new frog to all other leopard frog species in the region and determined that it is an entirely new species, soon to be named by the researchers. The wetland species likely once lived on Manhattan, and though it’s now only known to live in a few nearby locations, Yankee Stadium would probably be the bull’s-eye of a target drawn around its current image.

Feinberg, co-author of the study, is working on his doctoral thesis in the School of Environmental and Biological Sciences. He was doing research on the alarming decline of leopard frogs in the wetlands of New York and New Jersey when he noticed that the regional leopard frogs displayed unusual behaviors and peculiar croaks. Instead of the "long snore" or "rapid chuckle" he heard from other leopard frogs, this frog had a short, repetitive croak.

“When I first heard these frogs calling, it was so different, I knew something was very off,” Feinberg said. “It’s what we call a cryptic species: one species hidden within another because we can’t tell them apart by looking. But thanks to molecular genetics, people are really picking out species more and more that would otherwise be ignored.”

To find out if his hunch was right, Feinberg developed a partnership with Cathy Newman, a geneticist who was completing a master’s degree in genetics at the University of Alabama.

The two decided to team up on the project after Newman, who was working on an unrelated study of leopard frogs, asked Feinberg, an ecologist and regional amphibian and reptile expert, for assistance with her research. In this heavily urbanized area Newman expected the frogs to be either of two previously known species, or perhaps a hybrid of both at best. What she found turned out to be a totally new species.

“I was very confident that the genetic results were going to support the idea that this was a new species” Feinberg said. “As far back as the late 1800s scientists have speculated about the odd frogs but until the advent of molecular genetics, it was difficult to prove anything.”

Although the frogs were discovered in the New York, New Jersey metropolitan area, the bulk of the genetics research took place at UC Davis. The results of those “unusual frogs” whose weird sounding calls were different from leopard frogs were clear-cut: the DNA was distinct, no matter how much the frogs looked alike.

What this discovery proves, said Joanna Burger, professor in the Department of Cell Biology and Neuroscience in the School of Arts and Sciences, and Feinberg’s advisor on the project, is that even in densely-populated urban areas new species can be found. Because of the extensive extinctions over the last few decades from habitat destruction, disease, invasive species, pesticides and parasites, it is even more imperative that conservation concerns be addressed, Burger said.

“It is amazing to discover a new frog in Rutgers backyard and the metropolitan area of New York and New Jersey that was among us for a century without being recognized,” Burger said. “We need to do all we can to make sure that we protect it.” 

Citation
Catherine E. Newman, Jeremy A. Feinberg, Leslie J. Rissler Joanna Burger, & H. Bradley Shaffer. 2012. A new species of leopard frog (Anura: Ranidae) from the urban northeastern US. Molecular Phylogenetics and Evolution 63, 445–455.