news about northeastern Chorus Frogs
This page presents news relevant to northeastern Chorus Frogs since the 2001 First Annual International Conference on Northeastern Pseudacris triseriata in Kemptville, Ontario.
Frog-logged Stability at North Dakota's Theodore Roosevelt National Park.
McGill University studies declines around Ottawa, Ontario
No decline around Detriot, Michigan (2005)
Wal-Mart opponents play frog card (Vermont)
note on Montezuma National Wildlife Refuge, New York
Upland Chorus Frog decline in West Virginia
AUTUMNAL CALLING 2005: eastern Ontario.
Changes in Frog and Toad Populations Over 30 Years in New York State.
Mountain Chorus Frog decline (North Carolina)
AUTUMNAL CALLING 2004: eastern Ontario.
Rapid decline in Quebec
Psuedacris nigrita: discovered in Virginia
Phylogenetic relationships of the North American chorus frogs (Pseudacris: Hylidae)
Decline in New Jersey
UNIVERSITY of ROCHESTER MITIGATION PROJECT:news article.
UNIVERSITY of ROCHESTER MITIGATION PROJECT: letter of advice
Calling. in Minnesota
Decline in Louisiana
possible decline in Florida
Survey around James Bay, Ontario and Quebec:
apparent decline near Kingston, Ontario
No decline around Detriot and Ann Arbor, Michigan (2001)
Characteristics, movements, and health of a population in SW Québec.
Silence of the frogs spooks ecologists (eastern Ontario)
Recorder and Times report on 2001 Conference
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North Unit conducts frog surveillance program at national park. Unknown by the visiting public, a clandestine surveillance program was conducted this past summer at the North Unit of North Dakota's Theodore Roosevelt National Park. Only recently have details of the secretive program, involving cleverly camouflaged microphones and digital recorders hidden in the underbrush, begun to emerge. According to park wildlife biologist Michael Oehler, "frog loggers'' were placed at four separate locations within the North Unit.
Campers, hikers and visitors need not worry, though. Their conversations were not recorded. The program was instituted to monitor the calls of frogs and toads inhabiting the North Unit. The frog logging units recorded all sounds in and around selected bogs and wetlands several times each day. The frog loggers were placed in position March 21, just in time to listen in on the mating calls of the park's most abundant amphibian – the boreal chorus frog.
"It's a much lower-cost method than having field crews out there and we collect much more informative data,'' said zoologist Blake Hossack with the U.S. Geological Service stationed at the Aldo Leopold Wilderness Research Institute in Missoula, Mont. Hossack is the principal investigator heading up the frog logging project. "The boreal chorus frog is about an inch-and-a-half long. Its call is really loud with huge choruses that are just constant.''
While listening to the pillow talk of amorous chorus frogs may seem a bit odd, it is considered necessary research for compiling an index of population trends of the park's herpetofauna over the long term. The earliest collections of amphibian and reptile life in the park were made during the period of 1920-1922 and reliable studies since then have been sporadic. Since amphibians are generally considered indicators of the health of an environment, frog logging at the bog may prove to be an important clue.
"We collected data throughout the sampling period,'' explained Oehler. "I would say it's a success. It is neat to find out what's going on. We're not going to save the world or anything, but it's good to know these things can be used and are reliable in the field.'' Previous studies have shown there have been few changes in the distribution of amphibians within the park. However, those studies were conducted by visual observations and almost accidental collecting of species. Now, with the continued development of frog loggers, much more reliable data will become available.
"This is kind of a pilot project and pretty challenging,'' Hossack said. "These frog loggers are a new variety. In the past we used analog tape recorders. Now it's digital. We're working now to develop software to analyze the recordings.'' For now, someone has to listen to the recordings to detect the various croaks and ribbits coming from a variety of creatures. And there's a lot of croaking to listen to. The four frog loggers placed in position March 21 were set to record one minute of bog chatter at 10 different times during each day until they were removed June 26.
In addition to the sounds of the dominant boreal chorus frogs, other amphibians often chimed in. The soft call of the common leopard frog could be heard along with the "wailing cow'' sound of the Woodhouse's toad – a five-inch long toad whose call can often be heard up to a half-mile away. Competing for airtime was the Great Plains toad and the plains spadefoot. The spadefoot is a species that lives primarily underground, making rare appearances during spring rains. To date, it appears that the park's bog life is conducting business as usual. "Some species are more resistant to disturbances than others,'' Hossack said. "North Dakota does not look like it did 200 years ago, yet boreal frogs are everywhere.''
The USGS began using early versions of frog loggers in Colorado in 1994. Some were also used in Glacier National Park in Montana until the bears discovered them and presumably added them to their diet. Today's newer models, with microphones hidden in pop bottles and recorders tucked into camouflaged coolers for protection from the elements, may be used in the North Unit again next year. "If they feel that further monitoring is needed, we'll be more than happy to collaborate again and will,'' Oehler said. -- Kim Fundingsland, MINOT DAILY NEWS (N Dakota) 29 August 2006
David Green, a McGill University professor and director of the university's Redpath Museum of natural sciences... In the Ottawa area, the diminishing population of the striped chorus frog has experts concerned.
Modern farming practices and unchecked suburban expansion threaten to silence a frog's spring song, writes Janice Kennedy.
It happens each year during the cool nights of early spring. When the pools of standing water are still thinly crusted with ice in the soggy fields and meadows just outside Ottawa, a tiny frog decides the time is right to find a mate. A tentative soloist, he puffs up the vocal sac under his chin and starts singing his unique song, a krr-eee-k that sounds like a finger running down the teeth of a plastic comb. Then a wonderful thing happens. In the spaces between his krr-eee-ks, a second little guy joins in, his contribution forming a perfectly timed duet. Another duet starts up, then another and another. Pretty soon, as frogs all over the meadow sing their little vocal sacs out, the crisp nighttime air is bright with the hillbilly hootenanny of small male amphibians on the make.
The chorus frogs are at it again. "If you listen to a chorus," says David Green, one of Canada's leading herpetologists, "it's possible to hear all the frogs, because they all want to be heard. It's not a wall of sound. It's got a structure, and it's really very, very organized." Mr. [sic] Green, a McGill University professor and director of the university's Redpath Museum of natural sciences, has spent a lifetime listening to frogs and learning their habits. "All the animals try to be heard in their little calling space. You can hear the duets. It's not random at all."
The Ottawa area is one of the natural homes to the pseudacris triseriata, also known as the striped chorus frog, the western chorus frog and even the western striped chorus frog. ("Western" is misleading, though, since it refers to the western edges of the animal's geographic home, from the East Coast toward the continental centre. It does not refer to the continental West.)
The tiny brownish frog with the dark stripes -- so tiny it could sit on a toonie -- has long been a comfortable resident of the grasslands and swampy areas just outside the urban core of Ottawa-Gatineau. No fancy lakes or cottage country for him, thank you very much. A nice damp field will do just fine. The trouble is, the damp fields are disappearing. And so are the striped chorus frogs.
Modern farming methods and suburban development are to blame, says Mr. Green. "The older methods of farming were actually kind of good for a number of species -- open-meadow species like meadowlarks, bobolinks, chorus frogs. The modern farming practices are not so good." Modern methods, which include the use of pesticides and chemical fertilizers, do not encourage healthy frog colonies. Nor does the unchecked suburban expansion that reclaims wetlands and covers them with houses and asphalt.
In Canada, the striped chorus frogs are still fairly numerous in southern Ontario, but they are diminishing in this area and through the St. Lawrence Valley, including areas near Montreal. "In Boucherville," notes Mr. Green, "a nice little population of chorus frogs is now gone -- gone to housing development. That's what happens. More and more sprawl takes its toll."
The species is considered at risk in these diminishing areas. In fact, a scientific research project has been set up to monitor frog populations in Gatineau Park through a series of listening stations.
Monitor frogs? Why should we care? For all kinds of crucial reasons, says Mr. Green, who has been fascinated with the creatures since his boyhood in Vancouver. He started out loving dinosaurs at age three, graduated to snakes at six and found his life's calling at 10.
"When I was 10, I caught a toad -- a Western toad -- and that was that."
An abundance of frogs is a sign of a healthy environment, he says. "They serve a number of purposes. The utilitarian purpose is that they are small insect-eating predators, so they consume enormous numbers of insects, and in turn, they're eaten by other things in great abundance. "Their place in the natural food web is extremely important. They are food for a great many other animals, and they are predators for a great many other things." Disrupt the natural food web, he says, and the entire system alters in undesirable ways. "You've got more insects, fewer larger predators and the balance shifts." When we alter the way nature works, he says, we create an unknown future with a potentially nightmare scenario.
"We just don't know. We have some general ideas about what happens when you take apart food webs, but the consequences are unpredictable -- although not good. And they're different, in ways you don't know and can't plan for, in ways the economy isn't set up to cope with. Whatever happens, it's going to cost a lot of money."
Mr. Green says the environmental alarm bells about frogs of all types started going off toward the end of the 1980s. One of the more infamous disappearances around that time was that of the Golden Toad of Costa Rica, now extinct. In North America currently, "the Wyoming toad is hanging on by the tips of its toes."
Numerous other species are seriously threatened, he says, and in each case, the disappearance or extinction can be traced to a lost or altered habitat. The striped chorus frog that has long called Ottawa-Gatineau home is now facing a similar threat. Its disappearance would be a real shame. The little creature, which likes to climb grasses and stalks with its sticky padded fingers, does its bit for nature's balance and even provides an engaging touch of enigma, too. After they sing their mating song in spring and settle down with their families, they are no longer seen or heard. Summertime is not their time.
"They tend to spend most of their time underground. We don't really know very much about what they do in the summertime. We have no clue. It's not the only frog that we have no clue about, but around here it's the frog we have the least clue about. It's a mystery frog."
But before it disappears, it fills the springtime air with its haunting song. That's the other important reason to care about frogs, says Mr. Green. "People like them. They're part of the landscape. What would the world be without frogs to sing in the springtime?"
A diminished place, clearly. As long as their annual chorus continues to echo across marshy fields, the small striped creatures of this region are a sweet reminder of the poet Robert Browning's timeless observation: For the time being, God's still in His heaven. And all's right with the world. -- OTTAWA CITIZEN (Ontario) 08 July 06 The danger of a fading chorus
No Chorus Frog decline evident around Detriot, Michigan. Anonymous. 2006. 2005 Rouge River Watershed Frog and Toad Survey. Friends of the Rouge, University of Michigan-Dearborn, 12 pp. download the report from the Friends of the Rouge website
The Rouge River Watershed Frog and Toad Survey is a volunteer listening survey that has been coordinated by Friends of the Rouge since 1998. Volunteers are trained to recognize local frog and toad breeding calls and survey quarter-square-mile blocks within the Rouge River watershed from March through July... Drought conditions through early spring continued to make it difficult for amphibians that rely on spring ponds. Precipitation was below normal until June, yet every species was heard in a higher percentage of blocks surveyed than average. This probably reflects a bias towards surveying blocks with better habitat as volunteer interest drives what blocks are covered. ... For the fifth consecutive year, American toads were the most commonly heard species, this year in 74% of survey blocks. For the second year in a row, green frogs were the second most common at 64%. Chorus frogs, spring peepers and gray treefrogs tied for the third most commonly heard. This is good news after two years in which spring species were heard in fewer blocks...
[Species Accounts]: Western Chorus Frogs (Pseudacris triseriata triseriata) Western chorus frogs were heard in 57% of all survey blocks this year and in all seven subwatersheds. The riparian corridor along Michigan Avenue rang with the calls of these small frogs, 12 of the 12 blocks surveyed had them calling! Canton Township was also an active area for chorus frogs -- heard in 24 of 26 or 92% of surveyed blocks. Other areas with concentrations include Van Buren Township (6/7 or 86%) and Salem Township (11/13 or 85%). Spring Peepers (Pseudacris crucifer crucifer) Spring peepers were heard in 57% of survey blocks and in all seven subwatersheds. Maybury State Park and Walled Lake had the largest concentrations. All seven blocks in Superior Township had spring peepers as well as 13 of 14 blocks in Salem Township (93%) and 21 of 26 (81%) in Novi. [The Rouge River drains into the St Clair River through Detroit. Its watershed is approximately 1167 sq km and includes 48 municipalities in three counties.More than 50% of the watershed is considered urbanized with less than 25% remaining undeveloped, with a population of over 1.5 million people. There are more than 400 lakes, impoundments, and ponds in the watershed, the Rouge River itself has a total of 206 river km and is comprised of four major branches: the Main, Upper, Middle, and Lower]. from Friends of the Rouge website (return to Contents)
Wal-Mart opponents play frog card - Endangered species could play role in store permitting. by Lee J. Kahrs, ST. ALBANS MESSENGER (Vermont) 1 February 2006
St. Albans Town: State land-use permitting hearings began Tuesday for a proposed 160,000-square-foot Wal-Mart store in the northern growth center here. The only new bit of information came with regard to an endangered species - the Western Chorus frog.
At the American Legion Hall, familiar faces appeared before the microphone requesting party status to the project's state Act 250 application. They included Jon Groveman, attorney for the Vermont Natural Resources Council (VNRC), a non-profit, anti-sprawl environmental organization that opposes the proposed Wal-Mart, saying it is out of scale with the surrounding community. Groveman requested party status under almost every one of Act 250's 10 criteria, including 8A, wildlife and endangered species. It was there that Groveman's opposition grew to include concerns over the endangered Western Chorus frog. "Ecological records indicate that the 107.5 acre area that encompasses the project tract has been, and may continue to be, habitat for the state endangered Western Chorus Frog," Groveman said. He went on to say that any project that threatens the habitat of an endangered species "violates VNRC's organizational mission and places at risk the ability of VNRC's members to enjoy recreational activities."
The VNRC also represents a number of local property owners and 85 Franklin County VNRC members, including the grassroots Northwest Citizens for Responsible growth. The preliminary hearing held by the District 6 Environmental Commission, and Chairman Dan Luneau explained that there would not be an overview of the project. Rather, he asked those seeking party status to state their name, why they believe they may be parties to the application, and to give a brief synopsis of their concerns, including how many, of any witnesses they would be calling. Those who appeared were also asked to follow-up with a handwritten outline of their concerns to be mailed to the commission within five business days.
"This is for us to keep our arms around this thing and know what we're dealing with," Luneau said. The chair also said that the written outlines will help the commission establish a timeline for the Act 250 proceedings as a whole. The local Development Review Board process took 13 months, seven public hearings, and countless hours of testimony before the project was approved with conditions last June.
The operative terms regarding the Western Chorus frog are "has been" and "may continue to be." Although the frog was determined to have existed in Franklin County, no one has seen or heard one here since 1975. According to Middlebury College Research Herpetologist Jim Andrews, there were two separate populations located in Alburg in Grand Isle County in the 1980s and again in 1998. Since then, the frogs have neither been seen nor heard.
"Right now, we don't know where these guys are at all," Andrews said.
Northwestern Vermont and eastern New York State represents the far eastern border of the frog's habitat. They are more often found in the Midwest, particularly in Wisconsin, Minnesota, Illinois, and Ohio. The Vermont Department of Fish and Wildlife in a 2003 newsletter stated that the small Western chorus frog is a state endangered species. According to ANR's description of the Missisquoi National Wildlife Refuge in Swanton, the frog is listed under native reptiles and amphibians as "possibly" present in the refuge. In the ANR description of the Mud Creek Wildlife Management Area is Alburg, the frog "may also be present" there as well.
A healthy population of over 900 frogs in southwestern Quebec was studied in 2001.The 2005 New York State Herpetile Atlas lists an observation of this species in three survey blocks within the basin in Clinton and Essex counties. The little frog, measuring up to 1 1/2 inches long, sounds very much like the peepers often heard on summer nights, Andrews said.
But will it stop the Wal-Mart project in its tracks? Andrews said probably not. "From my perspective, the sad fact is, that's never happened," Andrews said. "Never has an endangered species stopped development in Vermont." Andrews maintains the Vermont Reptile and Amphibian Atlas, an on-line catalog of the snakes, frogs, turtles, salamanders and others native to the state. The herpetologist made it clear where his priorities lie when it comes to development. "As we consume land, we have to keep in mind that the amount of wildlife habitat is a finite resource," Andrews said. "As we consume more, there comes a time when you have to say, ‘Not here.'"
The District 6 Commission will issue a recess memo in the next few weeks with their findings as to who will receive party status. The next Act 250 hearing for the Wal-Mart project has not been scheduled. The entire hearing Tueday was likely the shortest on record regarding the Wal-Mart project at 40 minutes. (return to Contents)
Is snoring a turn-on? For frogs, it is. by Rick Marsi. PRESS & SUN-BULLETIN (Binghamton, New York) 29 April 2005
... a chorus frog, calling in spring from the edge of a marsh or flooded field. In early April each year, I hear western chorus frogs at Montezuma National Wildlife Refuge near Seneca Falls. They sound like a finger rubbing over the teeth of a comb. (return to Contents)
Frog songs going strong. by Chris Kidd. THE PARTHENON (Marshall University, Huntington, W Virginia) 3 March 2005
The Upland Chorus Frog has slowly disappeared from the West Virginia landscape since the 1980s, and can now only be found in the southeastern portion of the state. One who is fighting to keep the unique frog in existence is biology graduate student Jaime Sias, who has been studying the frog for her master's research project.
"I am interested in these frogs mostly because they are declining in the state of West Virginia," Sias said. "No one has investigated the natural history of Upland Chorus Frogs, Pseudacris feriarum before. I wrote an article in the West Virginia Division of Natural Resources magazine this winter asking for people to keep their eyes and ears open for possible Upland Chorus Frog sites, and so far I have gotten feedback from three counties in the eastern panhandle. One is a possible county record."
Upland Chorus Frogs have three stripes on their back and emit a loud voice which makes a sound similar to someone running a finger over the teeth of a fine comb. The frogs can survive in swampy areas, grassy swales, moist areas of woodlands and heavily vegetated ponds. The frogs also tend to breed earlier than any other frogs, sometimes starting as early as January. "They can withstand freezing temperatures and are able to take advantage of early breeding opportunities," Sias said. "I also learned that they are masters of camouflaging and escaping."
She said she wants to construct a management plan for conserving these frogs and plans to make a career out of helping animals in trouble. However, Sias does face one daunting task; her main research subject resides six hours away in Morgan, Hardy, Hampshire and Pendleton counties where the majority of the frogs reside. "Mostly it is just financially difficult," Sias said. "I have a DNR grant that I have been depleting for over a year now and mileage and the occasional hotel room adds up."
Sias' effort has been praised by those in her department, especially Zachary Loughmen, a fellow biology graduate student who Sias said has been a major source of information. "The fact that Jaime is interested in a frog is kind of interesting as far as her study is concerned," Loughmen said. "Most people like snakes and turtles and salamanders, so frog people are few and far between." (return to Contents)
AUTUMNAL CALLING 2005: Subject: [NatureList] Frog Calls
Date: Tue, 20 Sep 2005 09:23:39 -0400
From: "Valerie Kirkwood"
This morning I heard one Spring Peeper and one Chorus Frog. Time, one hour pre- and post- sunrise. Humid and warm (17 C), but no rain. -- Valerie Kirkwood, Acton's Corners, Grenville County. (return to Contents)
Changes in Frog and Toad Populations Over 30 Years in New York State. James P. Gibbs, K. Kristian Whiteleather, and Frederick W. Schueler. 2005. Ecological Applications, 15(4),, pp. 1148-1157
Abstract: Lack of historical data against which to measure population trends greatly hampers understanding the status of amphibians. In 2001-2002 we resurveyed a hitherto unexamined baseline of monitoring data established in 1973–1980 at some 300 sites in western, central, and northern New York State, USA, and contrasted population transitions with environmental conditions to identify correlates of population change in American toads (Bufo americanus), northern spring peepers (Pseudacris crucifer), western chorus frogs (Pseudacris triseriata), leopard frogs (Rana pipiens), and wood frogs (Rana sylvatica). At the regional level, loss of habitats along roadsides has been substantial (minimally 7-12% of sites), yet within remaining wetlands, populations of most anurans have not declined. At the local level, population disappearance was associated with elevated levels of acid deposition (in American toad, spring peeper, western chorus frog, and leopard frog), urban development (American toad and spring peeper), increased forest cover (western chorus frog), and high-intensity agriculture (spring peeper); whereas population persistence was associated with increased deciduous forest cover (American toad, spring peeper, and wood frog) and low-intensity agriculture (American toad and western chorus frog). Habitat configurations at surprisingly large spatial scales (5-10 km from surveyed populations) were most closely associated with transitions in local anuran populations, implying that largescale extinction-recolonization dynamics influence population transitions, a result land managers should consider in conservation planning. download a reprint from the CNAH pdf library (return to Contents)
Amphibians lose homes to encroaching humans, by Elyse Ashburn. GREENSBORO NEWS & RECORD (Greensboro, N Carolina) 1 November 2004
Greensboro: ...Amphibians' rate of decline has been slower in North Carolina than in other areas around the world, but researchers like Alvin Braswell say it's palpable nonetheless. Braswell, herpetology curator for the N.C. Museum of Natural Sciences, said the once-common green salamander is all but extinct. The state's gopher frog population has dwindled; the eastern tiger salamander is increasingly hard to find, and the mountain chorus frog is in danger of being silenced... (return to Contents)
AUTUMNAL CALLING 2004: Subject: [NatureList] Chorus Frogs
Date: Fri, 10 Sep 2004 09:21:39 -0400
From: "Valerie Kirkwood"
I heard several chorus frogs calling this morning, pre-dawn. I don't know whether the rain stirred them up, or what. I certainly haven't been hearing them in the past few weeks; or perhaps the calls were drowned out by the loud cricket song. Cricket song seemed diminished this morning.
The clear air this morning provided a nice view of the crescent moon, Venus and Saturn. My harbinger of winter, Orion, stood high over the barn roof. Another year has gone by, and so many goals are unmet. Such is life. -- Valerie Kirkwood, Acton's Corners, Grenville County.
commentary on the NatureList:
Stew Hamill reported calling in Wolford Centre. There was an active chorus at Valerie's place, morning and evening, 12-13 Sept, 2004, and they were still vocalizing at Valerie's as of the morning of 17 September. There were still Peepers calling there on the night of 7 October, but Chorus Frogs last called on 25 September.
At Stew Hamill's October 7, 2004, Wolford Township, Grenville County, 18T 436400 4964800
14h00 one Spring Peeper calling
23h00 one Chorus Frog calling
And the last calling heard by Stew was 1 November, Chorus Frog and Spring Peeper, one individual of each. In 2003, on 2 November, Stew had heard "a few Chorus Frogs here in Wolford.' It's perhaps suggestive that there's been unusually persistant calling by Chorus Frogs after the wet summer of 2004. (return to Contents)
Subject: Chorus frog rapid decline in Quebec
From: Isabelle Picard
Sent: Tuesday, August 10, 2004 3:40 PM
...I am currently working with Jean-François Desroches on a conservation plan of Chorus Frog in Monteregie (south shore of Montreal). We did a big survey this spring and realize that there is constant decline. Since 1992, at least 4 metapopulations disappeared. In april 2004, we realized an extensive survey and found that the total number of ponds remaining was 802 and that in half of these ponds the chorus index was only 1 (less than 10 individuals singing). These ponds are concentrated in only 9 extant metapopulations and 13 isolated populations. Since the spring, we recorded the complete disparition of 40 (5%) of these pond and that an additional 150 ponds are in immediate danger of disparition from residential development only this year. Only 3 of the 9 metapopulations are not in immediate danger of disparition. Althrought that we don't have complete number of pond affected in the past years because no extensive survey of ponds have been done before, we estimate that at least 25% of the range of the Chorus Frog disappeared since 1992. Chorus Frogs are officially designated as vulnerable by the provincial governement, but its habitat isn't protected. I would like that the Chorus Frog would be designated by COSEPAC (COSEWIC) too... -- Isabelle Picard (return to Contents)
Psuedacris nigrita: Frogs' trip surprises scientists - Previously unseen in Virginia, the Southern chorus frog has now hopped into five counties. by Rex Springston. TIMES-DISPATCH (Richmond, Virginia) 6 August 2004
Scientists have discovered a frog with a slow, Southern voice in southeastern Virginia. The animal, the Southern chorus frog, had never before been reported north of Beaufort County, N.C., about 125 miles to the south."It's way outside the range that was previously known," said Emily Moriarty Lemmon, a University of Texas at Austin graduate student who helped discover the Virginia frogs. The Southern chorus frog is common near the coasts of states south of Virginia. Scientists discovered the frog in two Virginia counties last year, then found it in three more counties this spring.
Lemmon and Chris Hobson, a state zoologist, were scouting the Grafton Ponds section of York County one night in April 2003 when they came upon the frog. "It was just kind of, wow, what is that thing doing here?" said Hobson. He works for Virginia's Natural Heritage program, which looks for rare species. The frog was not even suspected of living here, Hobson said. Plus, frog experts had been scouting Grafton Ponds, a well-known nature preserve, for decades. "At that point, it looked bewildering," Hobson said.
Hobson and Lemmon had been looking for two frogs common to southeastern Virginia - the upland chorus frog and Brimley's chorus frog. The call of those frogs is a sort of clicking sound. On warm spring nights, the frogs call quickly, and each call sounds like a thumb running down a comb. The Southern chorus frog makes a much slower sound, sort of a "tick . . . tick . . . tick."
Hobson said he had heard that sound before at Grafton Ponds but thought he was simply hearing a cold, slow Brimley's or upland chorus frog.
A few nights later, Hobson checked a spot, in Prince George County near Disputanta, where he had heard the slow "ticks" before. He found another population of Southern chorus frogs. This spring, Hobson and other scientists found the frogs in Sussex County near Wakefield, northern Southampton County and Surry County near Surry. Chorus frogs are small, brownish frogs that live in forests and fields most of the year. In early spring, they move to ponds to breed.
"They breed in humongous choruses. That's how they got their name," Lemmon said. She is studying chorus frogs in pursuit of a doctorate in evolutionary biology. The Southern chorus frog is about 1.5 inches long, olive green to dull brown, with stripes along its back that break up into spots.
Most likely, Hobson said, the frog has inhabited Virginia all along but escaped detection. Hobson discounted other possible answers. Discarded pets? Not in that many places. Frogs that moved north because of global warming? An unlikely journey requiring several river crossings. And the frog is hard to catch, Hobson said. You think you hear it in one place when it's really a few feet away. "It's a ventriloquist."The discovery, "a blip" scientifically, conveys an interesting message about the world around us, Hobson said. "Even though people have been doing surveys [in Virginia] for centuries, there are still things out there to find." (return to Contents)
Phylogenetic relationships of the North American chorus frogs (Pseudacris: Hylidae) Emily C. Moriarty and David. C. Cannatella, Section of Integrative Biology and Texas Memorial Museum, University of Texas, 24th and Speedway, Austin, TX 78712, USA, Molecular Phylogenetics and Evolution 30 (2004) 409-420
Abstract: We examined phylogenetic relationships of the North American chorus frogs (Pseudacris: Hylidae) from 38 populations using 2.4 kb of 12S and 16S mtDNA to elucidate species relationships and examine congruence of previous phylogenetic hypotheses. Parsimony, maximum likelihood, and Bayesian phylogenies are consistent and reveal four strongly supported clades within Pseudacris: (1) A West Coast Clade containing regilla and cadaverina, (2) a Fat Frog Clade including ornata, streckeri, and illinoensis, (3) a Crucifer Clade consisting of crucifer and ocularis, and (4) a Trilling Frog Clade containing all other Pseudacris. Explicit hypothesis testing using parametric bootstrapping indicates that previous phylogenetic hypotheses are rejected by our sequence dataset. Within the Trilling Frog Clade, brimleyi and brachyphona form the sister group to the Nigrita Clade: nigrita, feriarum, triseriata, kalmi, clarkii, and maculata. The Nigrita Clade shows geographic division into three clades: (1) populations of maculata and triseriata west of the Mississippi River and Canadian populations, (2) southeastern US populations of feriarum and nigrita, and (3) northeastern US populations of feriarum, kalmi, and triseriata. We find that subspecific epithets for crucifer (crucifer and bartramiana) and nigrita (nigrita and verrucosa) are uninformative, therefore we discourage recognition of these subspecies. Pseudacris regilla, cadaverina, ocularis, and crucifer are maintained in Pseudacris. download a reprint from the CNAH pdf library
* It seems that Ontario & Quebec 'Western' triseriata are representatives of a western lineage quite different from most eastern US triseriata, and likely the gap between the St. Lawrence and western NY triseriata is between the major divisions of the triseriata-nigrita-maculata-clarki lineage. Not to mention a thorough rattling and shaking up of P. ocularis, brachyphona, streckeri, and other ornaments of the organic world (F.W. Schueler).
* ...good historial zoogeography and it makes a lot of sense in most respects to me, though I can not buy linking southeastern Ontario polulation with a maculata line - however if there is a north-south cline in maculata-triseriata (so-called) in the west and the nothwest Ontario populations came from the northwestern segment and the the Ontario ones drove up through the prairie peninsula from the southwestern segment it makes sense. The southern Michigan sample which links to the eastern populations then is an eastern invasion and likely all the Great Lakes adjacent populations are a mix and the phylogenetic concept -if it admits populations overrunning each other and hybridizing is alive and well. The problem is 18th centuary sample sizes with a 21st centuary analysis. (Francis Cook). (return to Contents)
For N.J. species, it's not easy being green - Development threatens state's amphibians Michele S. Byers, New Jersey Conservation Foundation. HOMES NEWS TRIBUNE (New Jersey) 20 July 2004
Seven years ago, in the summer of 1997, Dave Moore, former leader of New Jersey Conservation Foundation, alerted us to a quiet war, which is still happening today. Here's what he said.
"It's an undeclared war: people vs. frogs and other amphibians, like salamanders. Amphibian species are being annihilated by people worldwide at an unprecedented rate. And technology is on our side!" ...lots of species we do know about are in decline, including a welcome harbinger of spring, the chorus frog. We need to protect natural areas where such creatures can survive. ... of New Jersey's 18 species of salamanders, fully half of the species are in danger. Almost half of our frogs are in the same category.
I hope you'll contact me at 1-888-LAND-SAVE or visit NJCF's Web site. for more information about conserving New Jersey's precious land and natural resources. (return to Contents)
UNIVERSITY of ROCHESTER MITIGATION PROJECT: Tiny frogs find new home at UR: Cooperation on pond project shows it can be easy being green. by Corydon Ireland , Rochester Democrat and Chronicle, May 10, 2004 -- For one community of marshland frogs in Brighton, 2004 was literally a leap year.
In late March, western chorus frogs successfully leaped from their old habitat off East River Road to a new one created for them less than 100 yards away. Their original home, a marshy wooded area called a vernal pond, was leveled last year during a $20 million project to expand the University of Rochester's laser lab, formally known as the Center for Optoelectronics and Imaging. The old pond's footprint is now under a massive brick structure that will house precision targets for laser beams. It's part of a sophisticated project to heat and compress common elements found in seawater in order to create fusion energy.
Near the very new is the very old: Vernal ponds, as ancient as time, are a kind of temporary wetland -- wet during late winter and spring, dry by late summer. They can be the size of mud puddles or cover hundreds of acres. At the laser lab, a stone's throw from the Erie Canal, the new pond is the same size as the old -- 16,000 square feet. A second manmade pond nearby of 4,500 square feet is an attempt to mimic the sunlit, grassy areas that western chorus frogs sometimes also use as a habitat. Both ponds include a design feature vital to the definition of a vernal pond: no fish. For 60 to 80 days in the spring and summer, the tiny egg masses laid by female frogs are vulnerable to aquatic predation.
UR's steps to save the Brighton frogs were voluntary, since vernal ponds have no formal protections in New York -- and even small wetlands are unguarded by the law. The university worked with its contract engineers and architects, with the local Sierra Club and with the Brighton Town Board to alter the building project and make room for the frogs.
Cornell University-trained biologist Frederick W. Schueler donated his expertise. He's curator of the Bishops Mills Natural History Centre in eastern Ontario, Canada. Western chorus frogs, an interest of his for 30 years, are on the "extreme edge" of risk in the frog world, he said, since very few survive the winter to mate. It makes preserving their springtime habitat that much more important. Once abundant along the St. Lawrence River and on the eastern shore of Lake Ontario, the tiny striped frogs now confront an ever-shrinking habitat, Schueler said.
Vernal ponds are protected by law in Massachusetts, he said, making their design a more common element in building projects. In New York, "you don't find this in the design books too easily," said Paul Tankel, UR's architect, who toured the larger pond Wednesday. He found out only early last year that western chorus frogs sounded their primal trill in the back yard of a high-tech research lab. An environmental review of the project missed the frogs altogether, although they are rated "restricted," or at risk, by the U.S. Geological Survey.
Sara Rubin inspired the pond project last year by speaking up at a Brighton Town Board meeting where Tankel was outlining the UR expansion project. "Western chorus frogs are kind of an icon for this area," said the Brighton potter, who's a member of the local Sierra Club's wetlands committee. In New York, Rubin said, the species known to experts as Pseudacris triseriata now inhabits only a narrow band of coastal plain along Lake Ontario. In the Rochester area, the inch-long frogs are found off Bailey Road in Henrietta and near Meridian Park in Brighton, where on some days the grassy ground "seems alive" with the frogs, said Rubin.
A species in decline: Despite a few thriving habitats in Rochester, western chorus frogs are losing ground in the 13 U.S. states where they are found and in the province of Ontario. In recent data from a 1995-2000 Canadian marsh-monitoring program, western chorus frogs were the only frog species that showed signs of population decline. "Right now, the frogs seem like a silly, tiny little issue," said Rubin, who this year became a member of Brighton's conservation board. "But it's not going to be, as more and more (habitat) gets filled in."
A recent study by Cornell University and the Brookings Institution, a Washington, D.C., think tank, showed that urbanized land in upstate New York grew by 30 percent between 1982 and 1997. But the population grew only 2.6 percent. That's an indication that rural land, with its abundance of animal habitat, is being gobbled up. Western chorus frogs are among the first amphibians to sound off in late winter or early spring. They are as noisy as they are relatively rare. During mating season in the spring, males sing day and night in half-second, rising trills that sound like a fingernail running along the small teeth of a plastic comb. The frogs typically live only a year, and they favor two types of habitat: lowland wooded areas that act as temporary wetlands, like the UR site, and "successional" (abandoned) farm fields, which provide shallow cattail marshes and sparse tree and shrub cover.
Design details: Bob Bringley, a partner with Parrone Engineering in East Rochester, oversaw the pond project. "I've never been (asked) to build a pond for frogs before," he said. A Parrone design team put in up to 80 hours of work. The construction phase, last fall when the frogs were out of the marshy area, lasted three weeks. The first step was to scoop up 4 inches of muck from the old vernal pond and transfer it to the new site. That was an attempt, apparently successful, to transfer the microorganisms that helped make the pond attractive to western chorus frogs. The muck contains all the eggs of the invertebrates that inhabit the vernal pond, including snails, pea clams and one primitive creature that hasn't changed since the Ice Age, the fairy shrimp. "Look into the water, and it looks like thin soup," teeming with planktonic life, said Schueler.
The larger new pond looks glassy and brown and is ringed by rocks. Three old trees, island-like, rise out of the water. But there are subtleties in the design. The water averages 18 inches deep -- shallow enough to dry up in the summer, but deep enough to protect the frogs. And the pond's bottom is undulant, carved with deliberately deep areas where the frogs can shelter in times of drought. "It was perfect," said Tankel of the pond, designed to lure the critters back into a reproductive cycle. "We knew the frogs would come."
Looking to the future: Brighton has set up an escrow fund for the new vernal ponds. If frogs have not taken hold after three years, the money will go toward fixing any problems there. "But now that they're home," said Tankel of the frogs, "we expect they'll just keep coming back." During the dry season, western chorus frogs forage in nearby grassy or wooded upland areas. In winter, they burrow underground to hibernate. They're secretive, skittish and hard to spot. But their loud springtime mating calls can be heard up to a half-mile away.
SWBR Architects in Rochester is overseeing the laser lab expansion project, which is expected to wrap up in December. The vernal pond cost a fraction of 1 percent of the total expense, said David Beinetti, the firm's president. Building the pond wasn't a monetary decision at UR, he added. "The profession, including engineers and architects, are accountable for protecting the environment." UR has promised to monitor another potential problem at the site, said Rubin: phragmites, an invasive reed, and tall buckhorn, a fast-growing aquatic weed. The two invasive plants could choke off diversity in the facility's new stormwater retention pond, just a few steps from both new vernal ponds. But so far the little frogs that could (and did), the new ponds and the cooperation that made the project possible have produced a rare environmental success story, said Rubin.
"Everybody worked together," she said. (return to Contents)
UNIVERSITY of ROCHESTER MITIGATION PROJECT: letter about Chorus Frog habitat at University of Rochester
Date: Tue, 10 Jun 2003 11:21:55 -0400
From: "Frederick W. Schueler" <email@example.com>
Office of the University Architect
University of Rochester
212 Fauver Stadium, Box 270346
Rochester, NY 14627-0346
Chairman, Brighton Conservation Board
Brighton Town Hall
2300 Elmwood Ave.
Rochester, NY 14618
To whom it may concern,
Sara Rubin, having told the Brighton Conservation Board and the University of Rochester architecture team about my experience with Western (Midland) Chorus Frogs (Pseudacris triseriata triseriata) in New York and adjacent jurisdictions, invited me to examine the prospects for remediation of a Chorus Frog breeding pond that is in the path of the proposed expansion of the Univeristy of Rochester Laboratory for Laser Energetics at 250 East River Road, Brighton.
I visited the site on the afternoon of 24 May 2003 with Sara Rubin, Dave Fader (Brighton Planning Board), Paul Tankel (University of Rochester architect), and Bob Brinkley (U of R engineer), and Jessie Anne Werner (Brighton Conservation Board). After a wet spring we found water levels were still high, allowing a better assessment of conditions in the breeding season than would have been possible in a dry May.
The present breeding site is a shallow (50cm) pond in dense clay, about 30x40m in size, entirely within the boundaries of the pending expansion of the lab. There is a sparse coverage of Cattails, among other aquatic plants. The surrounding woods are open second growth with trees of Ash and Black Willow, a dense shrub layer, and ground cover in which Sensitive Fern, sedges, and Horsetails (Equisetum) were conspicuous. The present canopy trees had grown up around open-field species such as Apple, Hawthorne, and European Buckthorn (Rhamnus cathartica): this is a first-generation forest, and retains many signs of its origin as an oldfield. This represents one typical kind of Chorus Frog breeding habitat: an isolated vernal pond in open successional woods. I won't rehearse here the evidence that this species is declining in abundance in New York and throughout its range in the Great Lakes drainage basin. There is, however, increasingly diverse evidence that it's being severely squeezed by habitat loss from secondary succession on one hand and intensified human land-use on the other.
Chorus Frogs are a species typical of wet brushy fields and temporary (vernal) ponds. They are freeze-tolerant, and hibernate on the forest floor, some within 50m of the breeding pond, and some >100m from it. On the first warm days of spring they gather in the breeding pond, and lay eggs in inconspicuous masses that are attached to vegetation. The larval period is 50-60 days, and many breeding ponds dry completely in mid-July to August. The transformed juveniles disperse into the surrounding habitat, and grow to adult size in one summer; most adults, after the exertion of breeding, do not survive a second summer, so the breeding population is dominated by first-year frogs. (pers. comm, Jean-François Desroches, see Characteristics, movements, and health of a Western Chorus Frog (Pseudacris triseriata) population at a breeding pond in southwestern Québec.)).
While some ponds maintain robust breeding populations for years at a time, there are also changes from year-to-year in which ponds support choruses, and also changes in which ponds successfully produce transformed young. Chorus Frog tadpoles are especially vulnerable to predation by fish, and the presence of even small fish can seriously depress breeding success of spring-breeding frogs. Accordingly, the important considerations in designing a breeding site for Chorus Frogs are:
1) NO FISH! (enforced by a vertical spillway, at least 30cm, and ideally >50cm, at the outflow)
2) the pond dries out by September, or is drainable in case fish get in,
3) alternative breeding sites are provided for breeding in alternative ponds depending on water levels and predator invasion,
4) plenty of sun-warmable shallows in the ponds for tadpoles.
5) surrounding access to moist ecotone, shrubland, or open (grassy) forest for at least 100m radius for adult foraging and wintering.
The following plan, decided upon among us on site, meets all of these criteria:
1) The existing deep pond will be essentially "moved" to the east, by digging and enlarging the shallow wet area that is already there. This is intended to replace the present main pond. It should therefore mimic the original pond in depth profile and in surface area, that is, the new extension should be of the same depth, about 50cm (18"), and the same surface size. Overflow from this pond would either drain around behind the new building to the culvert where it now drains, or over a vertical spillway into the stormwater retention pond.
2) Care will be taken to preserve seeds and eggs from the existing wetland, by scraping off the pond's topsoil and placing it into the new ponds at corresponding depths, etc. This will encourage a continuation of the plant and microscopic animal life that has support the amphibian population. 3) A second "Insurance" pond should be dug in a depression to the south of the existing pond, somewhat to the south-east of the new extension. This pond would be smaller in surface area but should be deeper than the existing pond, i.e. one meter deep instead of 50cm. It would be a backup in case the other pond doesn't function as well as we hope, and its greater depth would allow it to serve as a successful breeding site in very dry years. It would be confluent with the ‘moved' pond at highwater, and would drain by the same route.
4) An additional excavation in the open slightly depressed area to the south of the new stormwater retention pond would create an excellent "Grassy Swale" pond. This kind of open sunny exposure is also characteristic of Chorus Frog breeding sites in our area. (On the afternoon of 25 May 25, we found abundant Chorus Frog tadpoles in the flooded, grassy, slightly shrubby field at the north side of the Summit Apartments in Brighton). This third pond would be different in character from the other two, and would serve as an alternative site if the others eventually failed by becoming too densely treed, by being filled in through erosion, or for some other reason.
5) A method must be devised to insure that water from the stormwater retention pond will not in flood conditions be able to reach and contaminate the "Grassy Swale" pond; probably a vertical spillway to handle any overflow drainage from the pond.
6) Care must be taken to eradicate and not allow the spread of the Phragmites plumed grass which is presently found around the ditch at the outlet of the storm sewer. The European race of Phragmites can rapidly crowd other vegetation out of wetlands. Seeds and rhizomes can be carried on construction equipment, making this the first plant to establish itself in disturbed soil. It is extremely invasive, crowding out native plant species and creating a monoculture not adapted to the needs of native wildlife. These plants should be cut down before they flower and form seeds. A type of "geo-fabric" could be placed over the stand to kill it. None of the earth where Phragmites is found should be moved, to avoid spreading it mechanically. In the spring all the young shoots should be pulled out.
Since stand is in a site that is shadier than is ideal for Phragmites, eradication or at least containment should be possible. Vigilance should be exercised (and small plants pulled) to keep Phragmites from becoming established in the stormwater retention pond.
7) When the adult Chorus Frogs leave the water after mating and laying their eggs, they go "upland" to their summer habitat, which is characteritistically ecotone areas between woods and fields. The present lightly wooded nature of the area does qualify as good summer habitat, verified by the viable population existing there now. However, for long term success, brushy/grassy/lightly wooded summer habitat will have to be maintained. To achieve this, the edges of the retention pond should not be mowed within a four or five meters from the water, leaving a ring of higher grass around the pond. The area between the retention pond and the "Grassy Swale" pond should also not be mowed, creating a corridor for frog upland travel in the summer (this unmowed area could very well discourage the annoyance of large numbers of Canada Geese, and could be made aesthetically quite striking with native, moisture tolerant plants like flowering Mallows, Pussy Willows, sedges, etc). If in the future it is noticed that the woods are becoming too thick, management should include postponing canopy closure by removal of alien species, such as European Buckthorn and Honeysuckle (Lonicera tartarica).
8) Since Chorus Frogs seem to usually live only one year, and since they are early spring breeders, work in their existing pond should not be begun before July when the tadpoles have transformed into froglets and have left the water.
9) Volunteers will be welcomed to monitor any of the various stages of habitat construction, as we realize it is very difficult or impossible for the engineers to keep watching every detail as it is being done. As each of these points are being agreed to in good faith by everyone involved, and we should see that they are carried out correctly by the construction crews. The land behind the lab has a large number of picnic tables, attesting to the interest in the out-of-doors among workers at the lab. Interpretive signage could add to the public's understanding and enjoyment of the area and the project.
10) Look into the Letter of Credit which would hold some funds in escrow in case the habitat was not successful. (however, "success" will have to be defined on a variety of temporal scales - construction of the site according to plans, initial occupancy by Chorus Frogs, and medium (5 years) & long-term (10+ years) persistance of the population).
It was gratifying to see the seriousness with which the University of Rochester architects take the concerns for this site. As is evident from the above synopsis, they have gone far beyond a nominal mitigation effort: creatively proposing three pond locations that fit very naturally into the existing land conformation, planning long-grass buffer zones and corridors, inviting volunteer monitoring of the construction. They are actively trying to make the wetland as good and even better than it was, bigger and with opportunities for a more diverse biota.
The resulting wetland, if functioning and successful, would bring credit to the University of Rochester as a showplace demonstrating cooperation between a conscientious community Conservation Board and institutional needs, as well as being a testament to responsible stewardship of this region's valuable and unique ecological heritage.
Frederick W. Schueler, Ph.D.
Bishops Mills Natural History Centre
(return to Contents)
Cricket Frogs Calling. by Jim Gilbert. WACONIA PATRIOT (Minnesota) 16 April 2003
...On warm spring days, and nights too, listen for the swamp cricket frogs, also known as chorus frogs, calling from grassy ponds and roadside ditches. We first heard them on March 23 when the air temperature went above 70 degrees F for the first time in 2003. The great volume of the mating tills produced by these tiny frogs, which have bodies a little over an inch long, suggests that it is coming from much larger frogs. The sound is like that of metallic clicker.
It's the males that call, and I have watched them at night with the aid of hip boots and a flashlight. Only their tiny heads with extended bubble-like throat sacs stick up above the water. With many males calling in a small pond, their combined chorus is continuous and quite deafening, but in the daytime the slightest disturbance causes them to remain quiet. A person walking near a pond of singing frogs causes the chorus to stop short. However, if one is perfectly quiet and doesn't move, soon an individual frog will begin singing, and in a few seconds the whole chorus will again be in full voice.... (return to Contents)
Reptile census far from a coldblooded calling - Scientists in park hunt species amid the mud. by Sandra Barbier. TIMES-PICAYUNE (New Orleans, Louisiana) 8 July 2002
... Night and day, several days a week, that was Anderson's life for nine months as he and Southeastern Louisiana University professor Richard Seigel searched the puddles and ponds, leaf litter, logs and marsh grasses for reptiles and amphibians in the Barataria Preserve of Jean Lafitte National Historical Park and Preserve near Marrero.
Anderson and Seigel finished the reptile and amphibian survey about three weeks ago. They captured more than 2,600 reptiles and found almost 50 species at Jean Lafitte, including some surprises. They found a small-mouthed salamander, an amphibian that had not been seen in the area for 30 years, Anderson said. On the other hand, they didn't find any chorus frogs, which were in the park just a couple of years ago. Jean Lafitte likely will become a kind of island in a few years, its animals cut off from others by destruction of wilderness. At that point, he said, "You could expect some of them to go extinct."... (return to Contents)
Concerned residents help count frogs - Participants take to the wetlands to help by Kevin Lollar, NEWS-PRESS (Fort Myers, Florida) 24 June 2002
...In its first two years, Southwest Florida Frogwatch has seen declines in such species as oak toads, chorus frogs and leopard frogs and increases in green treefrogs and pig frogs. [John] Cassani said. "We just came off two years of drought, and we need additional years of information with something resembling normal rainfall to see what's going on." (return to Contents)
SURVEY AROUND JAMES BAY, ONTARIO AND QUEBEC: In James Bay Boreal Chorus Frogs Pseudacris [triseriata] maculata are at the eastern limit of their range, which extends narrowly around the shores of the Bay in the grassy border of flat land newly emerged from the Bay by isostatic rebound from the weight of the Wisconsin glaciation. In May and June of 2002 the James Bay Expedition sought Chorus Frogs around Moosonee in Ontario, and 85 km east of there at Rupert Bay in Quebec. In 1971-72 FWS had marked the southern range limit of Boreal Chorus Frogs at Store Creek in the middle of the cettlement of Moosonee, Ontario. In 2002 Chorus Frogs were not heard from the settlement of Moosonee, where many of the ditches along the streets have been filled in,.nor from the grassy-boggy clearing around the airport, where they were heard in 1972, and where the habitat still seems adequate. Chorus Frogs were heard in good numbers at Whitetop Creek, at on the west shore of the mouth of the Moose River. We found Boreal Chorus Frogs at Rupert Bay, Cabbage Willows Bay, in Quebec (taking the first Quebec specimen). The restriction of the species to barely-supratidal habitats suggests that changes to the salinity of Rupert Bay by projected hydroelectric projects may imperil the species here. -- Jean-François Desroches, Isabelle Picard, Frederick W. Schueler, and Louis-Philippe Gagnon. more about the James Bay expedition (return to Contents)
Enchanted by the songs of the planet: Two researchers probe the mystery of springtime love songs. WHIG STANDARD (Kingston, Ontario) 25 April 2002
Frontenac Provincial Park....eastern Ontario's biggest block of protected space at the headwaters of the Rideau Rive... John Main, a Westport metal sculptor and musician, is grinning as he enters this forest amphitheatre, which is flanked on the far side by a sheer granite cliff. The sounds of spring peepers, piercing the leafless woods, have long preceded his arrival.
Main is a volunteer frog counter for the Canadian Wildlife Service, and this is his fifth year collecting data on eastern Ontario species. His head cocks sideways and his eyebrows lift on high alert. Off to the left, a solitary sound akin to a thumb running down the teeth of a giant plastic comb cuts through the shrill symphony of spring peepers.
"Chorus frog," he says, with evident satisfaction. "That's the first one this year. They're getting rarer all the time." As if to prove it, there is no call from a rival male chorus frog throughout the rest of the early evening. But the spring peepers soon reach a deafening din... (return to Contents)
Frogs make comeback in Michigan - Large populations are good indicators of a healthy environment. DETROIT NEWS (Michigan) 11 October 2001
(AP): Green frogs may be thriving and the beleaguered leopard frog may be bouncing back in some areas, the annual state frog survey suggests, which is good news for those concerned about development taking over wildlife habitat. ...In the Ann Arbor area, based on sites surveyed for the statewide count, Mifsud sees numbers and locations of green frogs apparently on the rise. They're very adaptable to a variety of living conditions, including suburban back yards and new detention ponds, Mifsud says.
The wood frog isn't so adaptable.... Chorus frogs, spring peepers, American toads and gray tree frogs also are doing well. (return to Contents)
Characteristics, movements, and health of a Western Chorus Frog (Pseudacris triseriata) population at a breeding pond in southwestern Québec. -- Jean-François Desroches and Martin Ouellet, presentation at 2001 CARCNET meeting in Charlottetown, PEI. (go to original)
We studied a population of Western Chorus Frogs (Pseudacris triseriata) at a breeding pond in southwestern Québec. A total of 951 captures of 842 adults was made between 19 April and 28 May 2001, using a 225 meter-long drift fence surrounding the pond. Frogs were measured, weighed, examined for diseases and deformities, marked, and released. The majority of individuals (97.1% or 540/556) arrived from day 0 to 7, with a peak (57.9% or 322/556) at day 3. Almost all frogs (99.5% or 393/395) left the pond from day 15 to 39, with a peak on day 15 (44.1% or 174/395). The sex-ratio was biased in favor of males (489 males: 353 females). For males (N=54) and females (N=49) that were recaptured, the mean duration in the breeding pond was 24.2±10.3 days and 20.2±9.7 days, respectively. Including frogs caught after the breeding season, a total of 864 adults was examined (499 males and 365 females). Females were slightly larger (SVL=25.48±0.08mm, N=365; weight=1.08±0.02g, N=197) than males (SVL=24.66±0.07mm, N=498; weight=0.95±0.01g, N=253). The tibia length was correlated with the SVL for both sexes (r2=0.711, N=503, p< 0.001). Overall, 54 (6.3%) presented body scars or traumatic digit amputations and 22 (2.5%) had minor anomalies such as brachymely, syndactyly, or eye color variant (black eyes). Chytridiomycosis was diagnosed in 54 of 142 (38.0%) adult P. triseriata sampled during the breeding period. Chytrid infection is enzootic in this apparently healthy population and has not yet been associated to any cases of disease or mortality. (return to Contents)
Silence of the frogs spooks ecologists - Altered rain patterns: Amphibians are living indicators of environment change by Margaret Munro, NATIONAL POST (Toronto, Ontario) 4 June 2001
Dave Seburn and his wife recently bundled their two-year-old daughter into the back of their car at dusk and headed off in search of western chorus frogs. They bounced down back roads in the southeastern corner of Ontario for hours, stopping to eavesdrop on the late-night action at several ponds and marshes. It was a beautiful night that had plenty of amphibians singing. But the Seburns arrived home about 2 a.m., having heard not a peep from western chorus frogs at 20 locations that used to be hopping and humming with the grey-green creatures.
"It's very strange," says Seburn, who, like many biologists, worries about the decline of world's amphibians. Habitat destruction and pollution -- which are suspected in the recent deaths of hundreds of frogs near Nova Scotia's coal mines -- are the most obvious culprits driving down the frog and toad populations.
But increasingly, scientists believe there are more complex reasons for the dwindling numbers of amphibians, which are among the most sensitive living environmental indicators because they have both aquatic and terrestrial life stages. A recent investigation into the high mortality of the western toad in the snow-capped Cascade Mountains in the state of Washington shows how complicated the amphibians' problems can get. The toads lay strings of thousands of eggs in the crystal-clear mountain water. But more than 80% of the jet-black embryos in the seemingly pristine waters now turn white and die. Scientists have long suspected depletion of stratospheric ozone, and a resulting increase in ultraviolet radiation kills the embryos.
But a new report in the journal Nature says changing rainfall patterns in the Cascades are the real trigger. There is less water so the toads tend to lay their eggs in shallower pools. This exposes the eggs to more ultraviolet light, which in turn makes them more susceptible to a water-mould pathogen, Saprolegnia ferax, which attacks organisms that are injured or under stress.
"Stress-related disease is the one consistent factor that may link amphibian deaths worldwide, and we have demonstrated that amphibian stress in the Cascades is ultimately linked to recent global climate fluctuations," says Joseph Kiesecker, a biologist at Penn State University, who headed the team. Kiesecker says the circumstances and pathogens likely vary from place to place. What is important is to look at the big picture -- and its complicated and subtle details -- when trying to understand why populations are declining, he and his colleagues say. This is no easy task, given the variety of amphibians and the dearth of information on their populations. "We need much better baseline data," says Environment Canada's Brian Craig, who is helping co-ordinate a national Frogwatch program in which hundreds of volunteers listen for frogs and toads each spring in all of the provinces and territories.
There are 24 species of frogs and toads in Canada. Some species, such as the big and aggressive bullfrog, are spreading to places like southwestern B.C., and displacing native species. Others, such as the plains spadefoot, a toad-like amphibian found on the Prairies, are thought to be holding their own, but are so secretive they are seldom seen or heard. Others, such as the northern leopard frog, have dramatically declined.
The big spotted leopard frogs virtually disappeared from Manitoba in the late 1970s and there have been large declines in Alberta. No one knows why, although drought, the collecting of frogs for use as bait and in experiments, and habitat loss are likely contributing factors.
On the other side of the country, the western chorus frog appears to be in trouble in Quebec and southeastern Ontario, where Dave and Caroline Seburn are working with Environment Canada to assess the population of little tree frogs. The Seburns, who run a ecological consulting firm in Oxford Mills, have been poring over historical records kept by naturalists and finding notable silent spots where the frogs not been reported in decades.
The question is: Are the frogs gone or is it simply that no one is listening for them? To try to find out, the Seburns climbed into their car last month to retrace the 60-kilometre route taken in April, 1990, by a naturalist who had carefully noted western chorus frogs singing at 20 locations along the route. The weary pair, who can identify a frog call quicker than a 15-year-old can recognize a rock star, were heartened to hear other species of frogs singing at some locations. But they did not hear a single western chorus frog. It is important to find out why, says Dave. And not simply for the sake of the amphibians. "If it affects the frogs, there is a good chance it affects us too," he says. "We're all biochemical beings." (return to Contents)
Sounds of silence worry frog expert. by Mark Calder. BROCKVILLE RECORDER AND TIMES (Brockville, Ontario) 5 March 2001
Kemptville: More and more each spring Fred Schueler hears the sound of silence - and it's deafening. He fears that silence could sound the decline of the western chorus frog, a small green-grey creature whose call once ripped across spring nights in the countryside years ago. But now, the frog specialist says, many of the grasslands, small ponds and roadside ditches that once chorused with activity are silent from March to May during the creature's once noisy breeding season.
It was out of a fear of this decline that Schueler organized the First Annual International Conference on Northeastern Psuedacris triseriata, a conference of experts on the frog from Ontario, Quebec, New York State and Vermont to discuss the problem of declining numbers. The frog, whose scientific name is Psuedacris triseriata, was identified in Vermont by SchueleHTML>
He has set up a local monitoring program to keep track of where the frogs are, a series of 42 listening posts to record their call during breeding season. Since beginning in 1992, he says he has seen a drastic decline in a species no one worried about. "I thought I was setting up a (monitoring line) in an area where there were lots of chorus frogs to listen to," said Schueler, a research associate with the Canadian Museum of Nature. "I wasn't expecting to see a decline of chorus frogs from 17 stations where I could hear them to one in the course of just nine years."
There are those who are skeptical about Schueler's claims, including provincial officials whom he says believe the species is all right. As well, a researcher who recently analysed 6,000 records of call monitoring from 1858 to 2000 says he's not sure whether the species is in trouble across the province. "We've got 100 years of data from call monitoring programs and we can't decide whether it's increasing, decreasing, or static," said David Seburn, a herpetologist conducting the survey on behalf of the federal government. "There are obviously areas where there aren't any records (of calls) but whether that means no one's heard them or they're gone is the big question."
Researchers also don't know enough about the frog to know whether it's in decline or the decrease is part of a natural cycle. However, Seburn's research did show along the Ottawa-Brockville axis there are areas where frogs haven't been heard for four or more years, indicating there could be a problem in this area.
Schueler agrees there's very little known about the creatures and where they go after breeding season, so scientists don't know why numbers are declining. In fact, everyone at the conference agreed more research was needed in basic biology and on the creature's habits. However, Schueler and others suspect there could be several reasons for the species' decline in this area and across Quebec, New York and Vermont. Many of the smaller farms of the 1950s that once provided grazing grasslands and ponds in this area - ideal habitat for the frog - have been abandoned. Poor soil has meant they've been developed for housing, or let return to forest.
At the same time the fields started to grow back to forests, it created a better habitat for the wood frog. Scientists suspect wood frog tadpoles prey on chorus tadpoles.
Participants at the conference also believe the frog's numbers could be under siege by farm and other chemicals, particularly pesticides and nitrates that are getting into the small ditches and ponds the frogs breed in. Research at McGill University suggests pesticides can lead to DNA damage, as well as greater rates of deformity in frogs. Studies suggest rates of deformities can jump as high as 15 per cent from two per cent in populations tested, said Martin Ouellet, a researcher at McGill. There is also the problem of more efficient drainage systems on farm land. Many fields that used to have the smaller shallow ponds in them in spring that were ideal habitat are now tile drained, reducing the availability of breeding sites.
The conference finished with several recommendations to ascertain the extent of the problem with the frog. Participants agreed to:
* Try to resurvey areas that historically had the frog to find more evidence of a possible decline. It was suggested the herpetologists enlist the help of local birders to monitor for chorus calls. Birders will be out in the country anyway this spring doing their own surveys. Anyone who wants to help with local call monitoring efforts can call Schueler at 258-3107.
* Encourage the province to help with a study of habitat in an attempt to prove claims about habitat loss in the Kemptville creek watershed area. The study could be done using aerial maps from different periods already available through the Ministry of Natural Resources.
* Work on ways to educate developers and residents to see the benefits of creating habitats on their property for the frog. This could range from creating small backyard ponds, without any fish to prey on tadpoles, to creating ecologically sensitive golf courses that don't use harmful pesticides or fertilizers. (return to Contents)
Chorus Frog Conference
Chorus Frog Declaration
monitoring Chorus Frogs
results of Chorus Frog surveys
the status of