Amphibian Ecology and Conservation

WFS 433/533

Spring Semester 2019

University of Tennessee-Knoxville



Instructors:                          Dr. Matthew J. Gray (

Teaching Assistant:            Daniel Malagon (

Phone:                                    974-2740

Office:                                    247 Ellington Plant Sciences Building (MG) and 201 Ellington PSB (DM)

Meeting Time and Place     8:10–9:25 am  T,R      160 PBB (2 field trips required: 30 March and 12 April)


Course Goal:              To expose students to the life history, diversity, ecology, conservation, and management of amphibians through a combination of lectures, readings, class discussions, labs, and field experiences.


Expected Outcomes:             Students that successfully complete WFS 433/533 will have a basic understanding of amphibian identification (larvae and adults), physiology, life history, and ecology.  They will be aware of potential mechanisms of amphibian declines, understand how to sample amphibians, and be aware of conservation strategies.  


Required Text #1:     The Ecology and Behavior of Amphibians, 2007 (ISBN 9780226893341).  Available online via the UT Library

Author:                      Kentwood D. Wells


Required Text #2:     The Amphibians of Tennessee, 2011 (ISBN 1572337621)


Editors:                      Matthew Niemiller and R. Graham Reynolds


Journal Papers:         Occasionally journal papers will be assigned instead of or to supplement the required text.  Papers will be provided in class or on the course website.



Academic Assessment:


Weights of Academic Assessments:

WFS 433



WFS 533

· Test #1




· Test #1


· Test #2




· Test #2


· Test #3




· Test #3


· Amphibian ID Exam




· Amphibian ID Exam





· Lecture1


· Participation2,3




· Participation2,3


1Graduate student lectures will be 25-35 minute presentations on an approved amphibian ecology or conservation topic. Topics must be approved by 14 February.

2Participation includes attendance during two field trips. You will earn 5% for attending each field trip.  

3If you miss a field trip, you can either: (1) attend the Southeast PARC meeting (1 day), (2) write a 10-page scientific paper on an amphibian topic of your choice, or (3) accept the 5% deduction in your final grade.


Your course grade will be determined using the following scale:



Final Weighted Percent



Final Weighted Percent






















Extra Credit:            


You can positively influence your grade as much as 4.5% by volunteering for extra credit. Volunteer work must be related to herpetofauna, and can include work on university projects, with government agencies, or NGOs. For every 8 hours of volunteer work, your final grade will be increased by 1.5% up to 4.5% (24 hours total). All volunteering must be completed by 3 May 2019. A volunteer form (see below) must be filled out by the supervising individual. Scott Dykes (, Chris Ogle (, and Chris Simpson ( with TWRA are often looking for volunteer assistance. You also may participate in TAMP surveys (organized by the UT Student Chapter of The Wildlife Society).


Extra Credit Form


Extra credit also can be earned by attending the Annual Meeting of the Southeast Partners in Amphibian and Reptile Conservation ( The meeting is 14 – 17 February at the YMCA Blue Ridge Assembly in Black Mountain, NC. Your final grade will be increased by 0.5%, 1.5%, and 1.5% for participating in the meeting on 14, 15, and 16 Feb. Transportation will be provided (entire meeting attended). Registration ($30 for students) is required. Lodging and meal options vary ($185 – $377 for three nights), and reservations can be made at If you go for the entire meeting, UT van transportation will be provided, but you need to sign up by 29 Jan



Full Syllabus


Teaching Resources:


Required Tennessee Anurans

Required Tennessee Salamanders

Anuran Sonograms

Key to Tennessee Salamanders

Practice Exam – TN Amphibian Identification (ignore tadpole questions)

Bob English Lectures (#11 - #14):  


Required Readings:

Students who have not taken a General Ecology course (e.g., BIO 260, FOR 215) should read: .  (A copy of Molles is available for check out in 201 PSB).


TEST #1 Material


1)      Amphibian Evolution

Required Readings:

         a. What characteristic of amphibians prevents them from living in saltwater?
Wells: pp. 2-3
b. What are three possible evolutionary mechanisms that drove the transition of vertebrates from water to land?
Wells: pp. 3-5
c. According to Wells, does most of the evidence support monophyletic or polyphyletic evolution of the modern amphibians?
Wells: pp. 9-10
d. Be able to define paedomorphosis and given an example in amphibians.
Wells: pp. 11-12
e. Amphibians have unusually large genomes. What are some of the evolutionary consequences of a large genome, and how do these potentially affect amphibian physiology and life history?
Wells: p. 12
f. In North America, what is the most ancient caudate family and the most ancient anuran family?
Wells: p. 12-15

2)      Amphibian Biodiversity

Required Readings ANURANS

a. According to Wells (2007), two amphibian families could be considered “primitive”. Which characteristics is the author using to make this statement? Are both families “similar”; are they sympatric? Compare and contrast these two families using their ancestral characters. (pp. 16-17; 27)

b. Some amphibian families have bright colorations all over their body, when others have bright colorations only in certain parts of their body (ex. Pleuroderma brachiops), and others are the complete opposite having cryptic colorations (Leptodactylidae). What are some of the roles of color patterns in anurans? Know the names of the different color strategies and be able to list at least two families that present each of those strategies. (Wells pp-18-21)

c. Parental care is a trait that is seen in amphibians over and over (i.e., convergent evolution). However, in amphibians differently from other many other vertebrate classes, the males instead of females are the ones that carry this responsibility. Why do you think this is the case? Give examples of families that have parental care (Wells pp 19-21).

Required Readings: SALAMANDERS

a. What type of reproductive strategy do the least-derived caudate families possess? Wells pp. 56-57

b. Which caudate families possess functioning lungs? Which caudate families possess lungs that are present, but non-functional? Which caudate families are lungless? Wells pp. 58-65

c. Which caudate family is most speciose? Least speciose? Wells pp. 58-65.

d. What morphological and behavioral attributes best describe salamanders? Wells pp. 65

e. Be able to define convergent evolution and provide an example with caudates. Wells pp.65-66

f. Why is the evolution of miniaturization in caudates important? Wells pp. 67-68.

g. What are two possible explanations for the evolution of lunglessness in caudates? Which hypothesis appears to have more support? Wells pp. 69-70.

h. What morphological adaptations have evolved in terrestrial caudates? Have these processes occurred more than once? Wells pp. 70-73.

3)  Amphibian Anatomy and Physiology 


Required Readings:

• How does the amphibian body plan differ between the 3 clades and how does affect locomotion?  Wells p. 46-48
• •How do Anurans Eat? Wells: pp. 52-56
• What is a Caecilian and how do they move? Wells: pp. 77
• What is a Caecilian tentacle? Wells: pp.79
• What is the structure and function of amphibian skin? Wells: pp. 84
• Know the difference between the layers of the skin Wells: pp.84-86
• What are the types of glands? Wells: pp. 86
• How does skin function vary by body regions? Wells: pp. 86-89
• Know Amphibian External Anatomy. Niemiller and Reynolds (Amphibians of Tennessee): pp. 2-9

Supplemental Readings:
• All of chapters 3, 4, and 5, Wells: pp. 123-229

4)  Amphibian Immunology


Required ReadingsRobert and Ohta (2009).

1. Describe differences in immune response between larvae and adult amphibians (entire paper but summarized in Figure 3).


5)  Amphibian Microbiome


Required Readings





TEST #2 Material


6)  Salamander Courtship


Required Readings:

a.         Know the median home range for anurans and salamanders, and how they compare with birds and mammals.

Wells: pp: 230-231

b.        Know the 4 ways that salamanders communicate, and be able to describe their primary function(s). 

Wells: pp. 404-411

c.         Know the 3 locations of chemical receptors in salamanders, and the 2 chemosensory organs in the nasal cavity.  Also, know which sex the chemosensory organs are usually larger and why this may occur.

Wells: pp. 417-418

d.        In the work performed by Robert Jaeger and Alicia Mathis on red-backed salamander territoriality, know the most important determinant of territory quality.  

Wells: pp. 424-425

e.         Be able to describe the adaptive significance of internal fertilization via a spermatophore, and the difference between the duration that sperm survive in the spermatheca in ambystomatids vs plethodontids. 

Wells: pp. 459-461

f.         Understand the relationships between female body size and clutch size, female body size and egg size, egg size and clutch size, egg size and hatchling size, egg size and development rate, and developmental rate and temperature.

Wells: pp. 497-500

g.        Be able to describe selective advantages of species that produce small vs. large eggs, and the environmental constraints that may drive these relationships. 

Wells: pp: 502-504

h.        Know which mode of development has species that produce the largest eggs relative to body size.

Wells: p: 504


Supplemental Readings

Wells: pp. 254-266 (orienteering)

Wells: pp. 452-461 (external vs. internal fertilization)

Organ (1958)


7)  Amphibian Reproductive Strategies  


Required Readings:

  1. Be able to describe the differences between bubble and foam nests used in anuran oviposition.  Wells: pp: 472-478

  2. Be able to provide an explanation why some salamanders that deposit eggs in still water lay their eggs in clumps while others scatter single eggs. Wells: pp. 788-489

  3. Know which family of salamanders only exhibits direct development. Wells: p. 491

  4. Know the salamander genus that exhibits viviparity. Wells: p. 493

  5. Review the energetics of reproductive modes in amphibians. Wells: pp. 500-501

8)  Anuran Courtship


Required Readings:

a.       Understand the difference between home range, migration and dispersal.

Wells: pp. 230-231

b.      Know which age class disperses most frequently in an amphibian population.

Wells: pp. 243-244

c.       Be able to provide some hypotheses for the adaptive significance of homing (i.e., site fidelity). 

Wells: p. 253

d.      Know the principal site of extraocular photoreception and how amphibians use polarized light to orienteer.

Wells: pp. 261-264

e.       Be able to describe the 2 auditory channels in amphibians, and know which is sensitive to low frequencies (<300 Hz). 

Wells: pp. 322-324

f.       Be able to provide a couple examples of anurans that do not have vocal sacs, and an explanation of why this may have occurred.

Wells: p. 277

g.       Be able to describe unison bout calling and be able to provide some explanations why it may occur.

Wells: p. 297

h.      Schwartz (1991) proposed 3 hypotheses for the duration of unison bouts.  Be able to describe those and know which is most plausible.

Wells: p. 297

i.        Understand the difference between explosive vs. prolonged breeders, and be able to provide some reasons why cold-weather breeders and species that inhabit xeric environments may breed explosively.

Wells: pp. 339-341

j.        Understand factors that influence sexual selection in prolonged vs. explosive breeding systems.  Also, understand how energy allocation differs between prolonged and explosive breeders, and a few strategies that prolonged breeders may use to reduce energy spent on calling.

Wells: pp. 342-343

k.      Be able to provide at least 2 explanations why inguinal amplexus is considered more primitive than axillary amplexus.

Wells: pp. 454-456


Supplemental Readings

Wells: pp. 269-304, 314-316 (anuran calls)

                                    : Types of Anuran Calls: MP3 file from The Calls of Frogs and Toads by Lang Elliot (Stackpole Books)


9)      Parental Care


Required Readings: Wells (2007): Chapter 11, Kupfer et al. (2006)

1. What are the major types of parental care among anurans and which is considered to be the most common form? Wells, p. 517
2. In what ways have Anurans evolved to carry eggs on their bodies? Wells, p. 526-530
3. How do members of the genus Leptodactylus communicate with their tadpoles? Wells, p. 530
4. Which sex of the family Sooglossidae provides the parental duties? Wells, p 531-532
5. What is considered the most unusual form of parental care among Anurans? Wells, p. 536
6. How does parental care in Urodeles compare to parental care among Anurans? Wells, p. 540
7. What is an important consequence of salamanders that leave eggs too early? Wells, p. 541
8. What are the potential benefits of parental care that have been proposed? Which is considered to be the most reasonable benefit? Wells, p. 543
9. What are the costs associated with parental care? Wells p. 547
10. What unique form of parental care is exhibited in the caecilian species Boulengerula taitanus? Kupfer et al. (2006), p. 926
11. What is the cost to the mother using this particular form of parental care? Kupfer et al. (2006), p. 927


10)      Predators and Predation Avoidance Strategies


Required Readings: None


11)      Amphibian Movements and Connectivity


Required Readings: None


12)      Phenotypic Plasticity


Required Readings:  Adaptive plasticity in amphibian metamorphosis (Newman 1992)



TEST #3 Material


13)      Sampling Techniques


Required Readings:

           Marsh and Haywood (2010): Area based surveys

Wilson and Gibbons (2010): Drift fences, coverboards, and other traps

Skelly and Richardson (2010): Larval Sampling


a.       Know the difference between passive and active sampling methods and be able to provide an example of each.  Willson and Gibbons: pp. 230 – 241

b.      Be able to identify factors that a researcher must consider when determining “the best” trap type to use to sample amphibians.  Willson and Gibbons: p. 232

c.       What are the 3 main factors that are critical for interpreting data on amphibian capture rates using passive sampling methods?  Willson and Gibbon: p. 235

d.      What are some of the advantages and disadvantages of passive vs. active sampling methods for amphibians in terms of types and numbers of species captured, intensity of monitoring, and mortality threats?  Willson and Gibbons: pp. 234 – 240

e.       What are the median dimensions for plot/quadrat surveys and transect surveys for sampling amphibians?  Marsh and Haywood: p.249

f.       Be able to provide examples of some of the common uses/methods of area-based surveys for sampling amphibians and the main taxonomic groups they are associated with.  Marsh and Haywood: pp. 249 – 252

g.      What are the 3 main assumptions associated with drawing inferences from data collected during area-based surveys?  Marsh and Haywood: pp. 259 – 260

h.      Why is timing (e.g., breeding phenology, larval development) a critical factor in determining larval sampling efforts?  Skelly and Richardson: p.57

i.        What are some of the difficulties when using marking techniques for larval amphibians and what method is most recommended in terms of ease of marking and longevity of marks by the authors?  Skelly and Richardson: pp. 65 – 66


Miller and Gray (2009): SE PARC Disinfection Information Sheet #10 (know disinfectant concentrations)


 Supplemental Readings:

a.       Gray et al. 2013: Wetland Wildlife Monitoring and Assessment (section 7.3.1)

b.   PARC Inventory and Monitoring Guide (Graeter et al. 2013)

c.      Larval Sampling Data Sheet


14)      Amphibian Declines

Required Readings:

a.       What makes amphibians especially vulnerable to declines?

Wells: pp. 787-792

b.      What are some species in North America with relic populations?

Wells: pp: 793-794

c.       What is the region of the United States with the greatest number of species declining?  Also, be able to list a few species with distributions east of the Mississippi that are declining.

Wells: pp: 800-803

d.      Know which island in the South Pacific likely has the highest diversity of amphibian species per unit area in the world.

Wells: p. 795

e.       Be able to provide an argument for why we should care that amphibians are declining.

Wells: pp. 850-853


Required Readings: Importance of Amphibians

Hocking, D. J., and K. J. Babbitt. 2014. “Amphibian Contributions to Ecosystem Services”. Herpetological Conservation and Biology 9:1-17

1. Hocking and Babbitt describe four categories that ecosystem services can be divided. What are they? Pg.1
2. Give one example of amphibians fulfilling each of the ecosystem service categories described in the article. Pg.2-6
3. Describe one area of research Hocking and Babbitt believe is underexplored? Pg 9-10


Supplemental Readings

Wells: pp. 816-850 (hypotheses for declines)

Adams et al. (2013): U.S. Trends in Amphibian Occupancy

Frog Skin and Painkillers

Salamander Limb Regeneration Videos (Video1, Video2, Video3)


15)      Batrachochytrium dendrobatidis (Bd)

Required Readings:
Kilpatrick et al. (2010): Know the life cycle of chytrid, and how it infects and kills amphibians.
Bd Treatment (know 3 methods for treating chytridiomycosis)


Supplemental Reading:

        Voyles et al. (2018): Development of Disease Resistance

16)      Ranaviruses

        Required Readings:
        Gray and Miller (2013) (know all information)

17)      Batrachochytrium salamandrivorans (Bsal)

 Required Readings:
       Stegen et al. (2017): Ecology of Bsal (understand the results in Figures 1, 2, and 3)

Supplemental Reading:

        Van Rooij et al. (2015): Bd vs. Bsal Chytridiomycosis

18)      Toxicology -- No required reading.



19)      Climate Change -- No required reading.

Supplemental Readings:
a. Li et al. (2013): Climate change effects
b. Cohen et al. (2107): Bd and climate change


20)      Disease Intervention


Required Readings:

a.       Gray et al. (2017): Intervention strategies (pp. 343-354) 

b.       Woodhams supplemental: Managing chytridiomycosis 


Supplemental Readings:

a.       Bletz et al. (2013): Bioaugmentation

b.       Woodhams et al. (2016): Bioaugmentation


Podcasts: (MP4 Format unless noted otherwise)

1.      iTunes Instructions: (NOTE: it is best to watch videos using iTunes)

1)      Go to:

2)      Download Software

2.      Link to iTunes to Listen to Podcasts:  Launch Podcasts in iTunes U 

Slides: (PDF Format)

Lectures:  ID Exam

“Tennessee Anuran Identification”     (Matt Gray, UTK)

“Tennessee Salamander Identification” (Guest: Dr. Bill Sutton, Tennessee State University)

Lectures:  Test 1

                  “Amphibian Evolution: From Fish to Frog” (Guest: Dr. Becky Hardman, UTK)

                  “Amphibian Biodiversity” (Guest: Todd Pierson, UTK)

                  “Amphibian Anatomy and Physiology” (Daniel Malagon, UTK)

                  “Amphibian Immunology” (Guest: Dr. Louise Rollins-Smith, Vanderbilt University)

                  “Amphibian Microbiome” (Guest: Dr. Doug Woodhams, University of Massachusetts-Boston)

Lectures:  Test 2

                “Threat of Invasive Buckthorn to Amphibians” (Guest: Dr. Roberto Brenes, Carroll University)

                “Salamander Courtship” (Guest: Dr. Kevin Hamed, VHCC)     

                “Amphibian Reproductive Strategies: Part I” (Daniel Malagon, UTK)  

                “Amphibian Reproductive Strategies: Part II” (pages 4-7 only; Dr. Patrick Cusaac, UTK)  

“Anuran Courtship” (Dr. Matt Gray, UTK)

“Amphibian Parental Care” (Guest: Todd Pierson, UTK)

“Predators”  (Guest: Katie Harris, UTK)

“Amphibian Movements and Habitat Connectivity” (Guest: Dr. Val Titus, Green Mountain College)

“Phenotypic Plasticity” (only a required reading - see above: Newman 1992)

WFS 533 Lectures: Test 2

1)   Scott Hollis     

2)   Jonathan Cox    

3)   Ana Towe    


Lectures:  Test 3

“Amphibian Sampling I”  (Guest: Gabrielle Graeter, NCWRC and PARC)

“Amphibian Sampling II”  Guest: Todd Pierson, UTK  -- MP3 Audio Podcast)

“Amphibian Declines” (Dr. Matt Gray, UTK)

“Toxicology” (Guest: Dr. Jake Kerby, University of South Dakota)

“Batrachochytrium dendrobatidis” (Guest: Dr. Jamie Voyles, University of Nevada-Reno)

“Ranaviruses” (Matt Gray, UTK)

“Batrachochytrium salamandrivorans” (Matt Gray's Lab, UTK)

“Climate Change” (Guest: Dr. Jason Rohr, University of South Florida)

“Conservation and Management of Amphibians” (Dr. Matt Gray, UTK)

“Salamander Conservation” (Guest: Dr. Susan Walls, U.S. Geological Survey)

“Disease Intervention” (Guest: Dr. Doug Woodhams, University of Massachusetts-Boston)

“Amphibian Conservation Strategies: Captive Facilities" (Guest: Tim Herman, Indoor Ecosystems)





Spring Peeper: 

American Toad:

Southern Leopard:


Spring Peeper Trill:

Toad Release Call: 

American Toad Amplexus: 

Green Frog Laying Eggs: 


Salamander Courtship (Jim Organ, 1957):



Bsal in Europe: 
Bsal Rap:


TWRA Amphibian Identification: (frogs) and (salamanders) 

LEAPS Anuran Identification:             


Dr. Matt Niemiller's TN Amphibian and Reptile ID site: 


Dr. Matt Niemiller's Key to TN Salamanders:


Frogs and Toads of Georgia:       


Amphibians of the Great Smoky Mountain National Park:  


Larvae Identification:    and


PARC Habitat Management Guidelines:


Previous WFS 433/533 Websites

Spring 2018:

Spring 2017:

Spring 2015:

Spring 2014:

Spring 2013:

Spring 2012:

Spring 2010:

Spring 2009:

Spring 2008:

Spring 2007: