Amphibian Cover Board Monitoring Detects Possible Case of Scoliosis in Red-backed Salamander

A possible case of scoliosis was observed in this red-backed salamander (Plethodon cinereus).
The dimensions of the cells on our data sheet are 10 mm x 17 mm.
The defomity I am pointing out is the curviture along the body length.
There is a Eastern hemlock (Tsuga canadensis) needle stuck to the tail.  

We monitored Amphibian Cover Boards and observed a total of 56 red-backed salamanders (Plethodon cinereus) and 9 red eft stage of red-spotted newts (Notophthalmus viridescens).  This project consists of a total of 19 cover board grids located in suitable habitat for monitoring the blue-spotted x Jefferson Salamander hybrid (Ambystoma laterale x jeffersonianum) population on the property.  We observed one red-back salamander that displayed a deformity that could be a possible case of scoliosis.  I credit Brian Kleinman, Herpitologist at Riverside Reptiles, for suggesting this as a possible case of the deformity.  Although this is the first observation that we have recorded for the property, we'll continue monitoring our amphibian population to detect the frequency of this deformity.  The individual we observed displayed a full range of motion and speed so at first glance this deformity did not appear to affect the animal negatively.  The animal was living is a mesic forest dominated by Eastern hemlock (Tsuga canadensis), which was surrounded by shrubby and herbaceous wetlands.

Amphibian Cover Board Experiment Monthly Check -- September 2012

Amphibian cover boards were checked Friday, September 7^th and revealed some great finds. First off, there were a total of twenty-nine Red-backed Salamanders and seven Red Efts found underneath the cover boards. Also uncovered was one Spotted Salamander. Spotted Salamanders do not usually reside under the cover boards but are often found near vernal pools and in crevices of rock walls and tunnels. Most importantly, there were two Blue-spotted x Jefferson Salamanders at two different sites. Based on the small size of these two salamanders, we assumed that they had just metamorphosed into the terrestrial adult stage, which takes place by September.  


Blue-spotted x Jefferson hybrid Salamander

The conditions for checking cover boards Friday were ideal due to the heavy rain at the beginning of the week. The warm, humid weather, also contributed in creating moist soil conditions that are favorable for amphibians. Since fall is around the corner we can expect drier, cooler conditions, but we can still anticipate to see some salamanders under the cover boards. During the winter months when temperatures reach close to freezing, (32-41° F) salamanders will go into hibernation on land and burrow under logs, rocks, and loose soil in order to maintain a stable body temperature. During this time the salamander’s metabolism is greatly reduced, thus decreasing the amount of calories burned to successfully make it through the winter. By early spring, rain and warmer temperatures wake the salamanders just in time for the breeding season.



Spotted Salamander

Juvenile Red-backed Salamander



Amphibian Cover Board Monthly Check - July 2012

Red-backed Salamander with six newly hatched salamanders.
Photo by Erin Caruso 

Today’s monthly check of the amphibian cover board experiment grid revealed forty-six individual salamanders. The amphibians that Nicole Morin and I came across were mostly Red-backed Salamanders, although we did see five Red Eft, one Northern Two-lined Salamander, and one Wood Frog. Twenty-two Red-backed Salamanders were under the softwood cover boards and eighteen were discovered under the hardwood. Two of Red-backed Salamanders under the softwood were found coiled around their young. This was an exciting event to come across because this strengthens our theory that the cover boards provide a favorable habitat for salamander reproduction. In addition, their population growth signifies a healthy forest environment. When it comes to reproduction, Red-backed Salamanders are unique because they lay their eggs on land, while most other amphibians and salamanders such as the Blue-spotted Salamander attach their eggs to underwater twigs or vegetation. These underwater eggs hatch and go through an aquatic larva stage. In contrast, the Red-backed Salamander young go through the larva stage while still in the egg, and when they hatch, look like miniature adults. Since the month of August is usually when most salamanders emerge from their eggs, it will be interesting to return to the cover board experiment grid at the end of next month and see if we can find a higher abundance of baby salamanders.

Lead phase Red-backed Salamander with egg cluster.
Photo by Erin Caruso

The Effects of Dry Weather & Salamanders

Red-backed Salamander

Yesterday’s amphibian cover board check yielded a relatively small encounter rate of salamanders. A total of 23 Red-backed Salamanders were seen at fifteen cover board grids. Only one Red Eft was spotted as well as one White-footed Mouse. The low encounter rate could be due to the recent dry weather we have been having across the state. Although I checked the cover boards after yesterday morning’s heavy rain shower, the forest floor still seemed to be dry and what was once moving streams and filled vernal pools were now reduced to only mud. Moisture is necessary for the survival of many salamanders, especially the Red-backed Salamander which is born without lungs forcing it to breathe through its skin. Therefore the exchange of oxygen and waste gases through the skin demands a moist environment. The drought in Texas can be used as an example of how a long period of dry weather can diminish salamander populations. The already endangered Texas Blind Salamander population has dwindled due to the drought and was captured by the U.S. Fish & Wildlife Service to bring to a hatchery for a chance at preservation. As the summer progresses we hope to find a greater amount and diversity of amphibians underneath our cover boards. Whether or not this can be achieved can depend greatly on the amount of precipitation we receive.

A dry stream near Duck Pond.

Amphibian Cover Boards Yield Blue-spotted x Jefferson Salamanders

Blue-spotted x Jefferson hybrid Salamanders were encountered today while checking amphibian cover board grids. A total of fifteen grids yielded 2 Blue-spotted x Jefferson hybrids Salamanders, 11 Red-backed Salamanders, and 12 Red-spotted Newts (eft stage). The Blue-spotted hybrid Salamander is always an exciting amphibian to come across due to its endangered species status in Connecticut. The cover boards are used as a method to monitor their population at White Memorial.

Blue-spotted x Jefferson hybrid Salamander

Seven newly constructed cover board grids were checked today for the first time. Only three of the grids had salamanders underneath them, indicating that the grids without any salamanders were either not placed in appropriate amphibian habitat or the boards have not been there long enough to attract any salamanders. The recent hot weather also seemed to dry out the leaf litter under many cover boards, which is not favorable conditions for the moisture-loving salamanders. As the summer progresses I will be interested to see what other kinds of amphibians we find under cover boards and if the Blue-spotted x Jefferson hybrid Salamanders will become more prevalent.  

Red-spotted Newt

Red-backed Salamander

Amphibian Cover Board Monthly Check - June 2012

On Tuesday, June 19^th James Fischer and I went out to the Solnit Parcel to do the monthly check of the experimental amphibian cover board grid. We were able to encounter 93 salamanders; 45 under the softwood boards and 48 under the hardwood boards. The majority were Red-back salamanders, although we did see 2 Four-toed salamanders, 17 Red Eft, and one wood frog. We noticed that most of the salamanders that we found were located in areas of dense fern stands. These ferns provide lush habitat for amphibians by keeping moisture and leaf mold intact.



Four-toed Salamander (Hemidactylium scutatum)

We were lucky enough to find a female lead phase Red-backed salamander guarding her eggs underneath a hardwood board. This is not a common spectacle to come across because Red-backed salamanders only mate every other year. After laying her eggs the female will coil her body around them and protect the eggs for two months until they hatch. The eggs are laid in a cluster, so they are somewhat difficult to count, but I estimated there to be 30 eggs in the cluster. Once the eggs hatch the baby salamanders look like miniature adults and after two years will reach reproductive maturity.



Red-backed salamander (Plethodon cinereus) with eggs.

Amphibian Coverboard Experiment Monthly Check -- October 2011

Spotted Salamander (Ambystoma maculatum) discovered under a
cover-board just as it emerged from it's mole-like tunnel.
Photo by James Fischer  

I observed an amphibian at 57.6% of the cover-board (CB) stations yesterday.  This is the highest proportion of stations that detected an amphibian ever observed during our monthly visits to this site over the past 2.5 years!  This is exciting news but I want to tell you about another interesting observation that I made.

A yellow-hued Spring Peeper (Pseudacris crucifer) camouflaged
among newly fallen autumn leaves.
Photo by James Fischer  

The CB grid spans across two stands of trees, one stand is dominated by deciduous trees while the other are evergreen trees.  The CB stations under the deciduous trees detected more amphibians than the stations under the evergreen canopy.  This puzzled me while I was traversing the grid from station to station.  I walk the grid a systematic fashion so that it takes less time.  I walk the grid along the lines within the grid from the evergreen stand to the deciduous stand and back again.  But that question kept bugging me. Why were more amphibians observed under the CB's in the deciduous stand rather than the conifer stand?  I think I may know but I need to tell you about another pattern that I observed whilst walking the line.  This was a new pattern for me this season.  I was wearing my sunglasses while I was in the deciduous stand and not in the evergreen stand.  Okay, if I lost you, please keep reading because there is a reason why this is important.

Just as I was beginning to get frustrated with having to pull out my sunglasses from my pocket each time I entered into the deciduous stand, the light hit my eyes and my skin began to feel warm!  Yes, it was noteworthy moment but not the kind you may be thinking of.  I began to think that the amount of sunlight penetrating the forest floor could have been one factor causing this pattern.  It is now autumn in southern New England and many of the leaves have already fallen from the deciduous trees allowing more of the sunlight to reach the forest floor.  The CB's under the deciduous trees should be warmer than their evergreen counterparts, which explains why so many amphibians were observed under these boards.  But lets not rush to this conclusion too quickly!  There could be several other explanations.  I'll offer another possible process just to demonstrate how complex a walk in the woods can sometimes be to biologists and ecologists.

Northern Two-lined Salamander  (Eurycea bislineata) found
under a cover-board near a spring seep.
Photo by James Fischer

Another explanation could be that the leaf litter on the forest floor could also be warmer and more importantly dryer under the deciduous trees while the conifer stand could be cooler and moister.  The amphibians in the deciduous stands would seek out shelter that offers a moister environment.  The amphibians inhabiting the evergreen stand would not have to seek out these micro-habitats.  Moisture is very important to a group of organisms that breathe through their skin.  Moist skin allows for more oxygen to transpire than drier skin.  Amphibians breathe through their skin as an adaptation which has allowed them to lower their metabolism as they evolved which means they require less energy to live.

Who knew flipping cover-boards and a walk in the woods could be so complex...

Amphibian Cover-board Experiment -- Monthly Check

Red Eft Life Stage of the Red-spotted Newt
photo by James Fischer

We revisited the cover-board experiment grid and observed a few interesting patterns.  Faye Curran, a new student intern, helped us today with this project, please visit the blog in a couple days to read her introduction.  Recently, we have recorded almost 14 inches of rain from Hurricane/Tropical Storm Irene and Tropical Storm Lee.  Although most of the surface run-off has slowed, there is still quite a bit of water in the forest percolating into the soil column from vernal pools or bubbling out of springs.  The amphibian cover-boards encounter rate appears to have been affected by all of this precipitation.  A total of 65 of the 132 cover-board stations detected an amphibian, which is the second highest percentage of cover-board stations detecting amphibians since the project started 2.5 years ago.  We encountered a total of 79 Redback Salamander (Plethodon cinereus), 19 Red Eft (Notophthalmus viridescens), 2 Two-lined Salamander (Eurycea bislineata), 1 Four-toed Salamander (Hemidactylium scutatum), and 1 Wood Frog (Rana sylvatica).  The primary question of this project is to examine the differences between softwood and hardwood cover-boards amphibian detection rates using a pair-wise comparison experiment.  The softwood cover-boards detected a total of 57, while the hardwood boards detected 45 individuals.

Salamander Cover Boards

Red-backed Salamander photographed by

Dave Rosgen at WMF's Duck Pond Trail

On Tuesday, 8/23/11, I checked all 174 salamander cover boards at White Memorial's Ongley Pond, Lake, Windmill Hill, Butternut Brook, Interpretive, Duck Pond, and Pine Island Trails, Mott-Van Winkle Area, and the east slope of Windmill Hill. The results were rather disappointing: 50 Red-backed Salamanders, 7 Red Eft-stage Red-spotted Newts, and 2 Northern Spring Peepers. This is despite wet conditions which would seem to favor amphibians. However, I did find huge numbers of earthworms; many of them being of nightcrawler size. Some concern has been expressed by herpetologists about the growing numbers of earthworms (most of which are non-native species) and their possibly ill effects on salamanders. I found at least 500 earthworms under our salamander boards. Five days after this survey, Tropical Storm Irene hit, dumping 8 inches of rain on this part of Litchfield, and flooding most of our salamander boards. Yesterday I found 21 of the 25 boards at the Interpretive Trail floating in the Pike Marsh's flooded backwater. Two boards were missing, and the 2 remaining boards on land harbored 4 Red-backed Salamanders. Of the 20 boards at Mott-Van Winkle, 6 were missing. The remaining 14 boards harbored 3 Red-backs. I'm heading out now to check on the fate of the rest of the cover boards.

Amphibian Cover-Board Experiment Monthly Check -- July 2011

Wall Flower
A Grey Treefrog trying to blend into exterior of White Memorial's Green Barn.
photo by James Fischer

Becca Solnit and Ryan Gannon helped check amphibian cover-boards examining the differences of detection rates between soft and hard wood types.  We encountered 28 Redback Salamanders, 11 Red Efts, and 1 Spotted Salamander under the softwood boards.  A total of 20 Redback Salamanders, 17 Red Efts, and 1 Two-lined Salamander were observed under the hardwood boards.  We have a total of 132 stations examining the boards in a pairwise comparison, of which 45 (34%) stations had amphibians.  The weather was mild with temperatures in the mid 70's to low 80's (degrees Fahrenheit) and complete cloud cover.  Although the ambient relative humidity was high, the leaf litter and humus was fairly dry, which may explain why there were so few stations with amphibians today.

Amphibian Cover-Board Experiment Monthly Check -- June 2011

We checked our cover-board experiment comparing soft and hard wood types in a pair-wise comparison yesterday.  Olivia Riccio and Rebecca Solnit (granddaughter of the owners who donated the land that hosts this experiment) were cowhands by checking most of the boards and calling out the species identification as we progressed through the grid.  We observed 69 redback salamanders, 4 red efts, 1 spotted salamander, and 1 wood frog under the boards.  A total of 55 out of 132 stations detected an amphibian.

Spotted Salamander photo by James Fischer

Redback Salamander photo by James Fischer

Lead phase Redback Salamander photo by James Fischer

Red eft life stage of Red-spotted Newt photo by James Fischer

Adult Wood Frog photo by James Fischer

Amphibian Cover-Board Experiment Monthly Check

Redback Salamander (Plethodon cinereus) observed under a cover-board.

This experiment compares softwood versus hardwood cover-boards to observe if there is a significant difference between the detection rates of amphibian species inhabiting our temperate forests.  Redback Salamander (Plethodon cinereus) and Red Eft juvenile form of the Red-spotted Newt (Notophthalmus viridescens) comprise the bulk of the amphibian species we observe in our study site.  We check the boards once a month when the weather conditions meet a specific set of criteria which insures the bulk of animals are found under the boards rather than wandering throughout the study area.  This experiment began two years ago and we are entering into our third season.  We hope to publish the results soon, but we observed 56 Redback salamanders under the softwood cover-boards and 41 under the hardwood cover-boards.  Only 2 Red Efts were found under the softwood boards while 5 were observed under the hardwood boards.  Considering that we had freezing temperatures most nights only a few weeks ago, these observations suggest that we have quite a few animals in our study site.  Check back to hear more about our progress with this experiment.