Amphibian Ecology and Conservation

Instructors: Dr. Matthew J. Gray (mgray11@utk.edu)

Graduate Assistant: Roberto Brenes (rbrenes@utk.edu)

Phone: 974-2740 (MG), 946-1142 (BS), 974-3897 (RB)

Office: 247 Ellington PSB (MG), 258 Plant Biotechnology Building (BS), 201 PSB (RB)

Meeting Time and Place: 5:05–7:05 pm T,R 113 PBB (2 field trips required: 15 March and 6 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), anatomy, life history, and ecology. They will be aware of potential mechanisms of amphibian declines, understand how to identify and sample amphibians, and be aware of conservation strategies.

Required Text #1: The Ecology and Behavior of Amphibians, 2007 (ISBN 9780226893341)

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	20%	· Test #1	20%
· Test #2	20%	· Test #2	20%
· Test #3	20%	· Test #3	20%
· Amphibian ID Exam	15%	· Amphibian ID Exam	10%
· Mini-Presentation¹	15%	· Lecture²	20%
· Participation^3,4	10%	· Participation^3,4	10%

¹Mini-presentations will be 8-10 minute persuasive presentations attempting to convince the audience of a specific for cause amphibian declines. Two minutes will be allowed following presentations for questions. The class will vote on the top 3 presentations, and the winners will receive a gift certificate to Gander Mountain (see p. 4).

²Graduate student lectures will be 40-50 minute presentations on an amphibian ecology topic approved by the instructors. Topics must be approved by 7 February.

³Participation includes attendance on two field trips and two labs. You will earn 4% for attending each field trip and 1% for attending each lab.

⁴If you miss a field trip or laboratory, you can either: (1) attend the Southeast PARC meeting, (2) write a 10-page scientific paper on an amphibian topic of your choice, or (3) accept the percent deduction (4% per field trip or 1% per lab missed) in your final grade.

Your course grade will be determined using the following scale:

Grade	Final Weighted Percent	Grade	Final Weighted Percent
A	90–100%	C	70–76%
B+	87–89%	D	60–69%
B	80–86%	F	<60%
C+	77–79%

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 2013. A volunteer form (see website) must be filled out by the supervising individual. Scott Dykes (TWRA non-game biologist) is often looking for volunteer assistance (Region 4 Office: 1-800-332-0900; scott.dykes@tn.gov). You also may participate in TAMP surveys (organized by the UT Student Chapter of The Wildlife Society).

Extra Credit Form

Extra credit can be earned by attending the Annual Meeting of the Southeast Partners in Amphibian and Reptile Conservation (http://www.separc.org/). The meeting is 21 – 24 February at Hickory Knob State Park in McCormick, SC. Your final grade will be increased by 3.5% for attending the meeting from 22 – 23 February. Transportation will be provided. If interested, you need to sign up by 1 February if you are planning to travel with Dr. Gray. Registration ($50 for students) is required. Inexpensive accommodations are available (see website).

Full Syllabus

Teaching Resources:

Handouts

Required Tennessee Anurans

Required Tennessee Salamanders

Anuran Sonograms

Practice Exam – TN Amphibian Identification

Required Readings:

Students who have not taken a General Ecology course (e.g., BIO 250) should read: http://fwf.ag.utk.edu/mgray/wfs493/EcologyReadings.pdf . (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) Salamander Biodiversity

Required Readings:

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.

Supplemental Readings

Vitt and Caldwell: pp. 422-433 (book can be checked out from 258 PBB)

3) Anuran Biodiversity

Required Readings:

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).

d. Many families lay their eggs directly in the water, while others use leaves hanging over the water. What are the advantages or disadvantages of these strategies? Know examples of families that use each of these strategies.

Supplemental Readings

Wells: pp. 16-41

4) Amphibian Biogeography

Required Readings:

For Goin et al. readings, please speciation and the Duellman and Trueb readings, please see: biogeography

1. Please describe the difference between allopatric and sympatric speciation. Which is most common in nature? Goin et al. 179-180.

2. Define the difference between pre- and post-zygotic isolating mechanisms in amphibians. Please provide examples of each. Goin et al. 180-181.

3. Why are amphibians good models for studying biogeography? Goin et al. 193-195.

4. Why there is only one family of salamanders in the southern hemisphere? In your answer please discuss the adaptations of this family. Duellman and Trueb 483-485.

5. Please explain why salamanders of the genus Hydromantes (Plethodontidae) were at one time found in Europe and why Cryptobranchus is found in North America. Duellman and Trueb 484-485.

6. How do you explain the presence of a member of the Proteidae in Europe (Proteus anguinus), while 6 species of Proteids are restricted to the Southeast. Duellman and Trueb 484-485.

7. Where is the level of endemism higher, in oceanic or in continental islands? For example, Papua New guinea and Java or Zazibar (west of the Mozambique channel) and Madagascar East of the Mozambique channel). Duellman and Trueb 487-488.

8. According to plate tectonics theory (Wegener, 1912), Australia separated from Gondwanaland in the mid to late Jurassic (Approx. 140 mya) and drifted southeast to its current position 9279 miles from mainland Asia, while Madagascar separated from the continent during the middle Cenozoic about 35 mya (much more recently). However, the amphibian endemism is much higher in Madagascar than in Australia, why is that? Why doesn’t Australia have 100% endemism if separated so early? (Hint: Australia shares many families with Papua New Guinea, but few with Indonesia). Duellman and Trueb 489-490.

9. Why there are no Centrolenids in North America or Ranids in the southern tip of South America? Duellman and Trueb 490-492.

5) Amphibian Anatomy

Required Readings:

For the Duellman and Trueb readings, please see: (a) amphibian integument and (b) organ systems.

1. What are the two types of glands in amphibian skin? What are these glands responsible for producing? Duellman and Trueb 369-371.

2. Granular glands are normally known for their ability to produce toxic compounds. What other purposes are these glands used for other than producing toxins? Duellman and Trueb 370.

3. Describe three types of color producing structures in amphibian skin? What is the name for this type of general color-producing structure? Duellman and Trueb 374-377.

4. Please describe the major sections of the amphibian brain. In your answer please describe the major anatomical features of these sections and what purpose these features serve. Duellman and Trueb 390-393.

5. Please describe the anatomy of the amphibian heart. How is the typical heart structure modified in aquatic amphibians (e.g., Proteidae, Amphiumidae, and Sirenidae)? Duellman and Trueb 398-400.

6. What are the major ways in which amphibians respire? Please describe the process how amphibian lungs acquire oxygen. Duellman and Trueb 404-405.

7. What anatomical adaptations have frogs evolved for locomotion? How are the movements of anurans different from caudates? Wells 46-48

8. What behavioral and anatomical adaptations have anurans evolved for a subterranean lifestyle? Please describe the anatomical and behavioral differences between “hind-feet” and “head-first” burrowing. Wells 48-49.

9. Please describe the anatomical adaptations frogs and salamanders have evolved for arboreal lifestyles. What epidermal features of a toe-pad permit a treefrog to adhere to a substrate? Wells 49-51 and 65-67.

10. Please describe the anatomical differences between the feedings mechanisms of anurans and caudates. Wells 52-56 and Wells 70-73.

6) Amphibian Dissection Lab

Required Figures for Studying: Figure 1 and Figure 2

7) Amphibian Physiology

Required Readings:

1. Describe the amphibian skin, and explain how its adaptations allow amphibians to conserve water and exchange CO₂ and O₂. (Wells, 84-86)

2. Explain the function amphibian kidney, particularly in relation to Nitrogen excretion (Wells, 117-119)

3. Compare and contrast amphibian thermoregulation in water and on land, how can amphibians keep the temperature required for their metabolic function without active basking (as seen in reptiles) (Wells 137-140)

4. How do amphibians hibernate? Explain the physiological adaptations of amphibians (both salamanders and frogs) to hibernation in extreme climates. Comment on freeze tolerance. (Wells, 148-155)

5. Explain the differences and similarities of O₂ uptake in land and in water, how some species like Telmatobious coleus (Titicaca lake frog), manage to live underwater. Is this analogous to underwater hibernation? If so, how would you say is the metabolic rate of this species? (Wells 162-167)

6. Explain how the heart of an amphibian works (Wells, 168-170)

7. During times like aestivation or hibernation, the metabolic rate of amphibians has to be adjusted to survive long periods of inactivity. What are these adaptations? Compare metabolic rates between active and dormant amphibians (Wells, 188-194)

8) Amphibian Immunology

Required Readings: To be posted.

1. Describe differences in immune response between larvae and adult amphibians (Robert 2010)

2. Explain the role of glucocorticoids in immune response and stress. (Warne et al. 2011)

TEST #2 Material

9) Reproductive Strategies

Required Readings:

a. Be able to describe different strategies for anuran oviposition in standing water.

Wells: pp. 465-468

b. Be able to describe the differences between bubble and foam nests used in anuran oviposition and their adaptive significance.

Wells: pp: 472-478

c. Be able to describe the differences between two modes of salamander reproduction and their adaptive significance.

Wells: pp. 488-493

d. 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

e. Know which family of salamanders only exhibits direct development.

Wells: p. 491

f. Know the two salamander genera that exhibit ovoviviparity and viviparity.

Wells: p. 493

Supplemental Readings

Wells: pp. 465-493 (modes of anuran reproduction)

10) Salamander Courtship and Mating

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)

11) Anuran Courtship and Mating

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)

12) Larval Ecology and Metamorphosis

Required Readings:

What do tadpoles eat? Altig et al. (2007)

Wells:

a. Understand how limb development is different between larval salamanders and tadpoles.

Wells: p. 559

b. Be able to describe a few oral adaptations of larval salamanders that assist in suction feeding.

Wells: pp: 561-562

c. Know whether salamander larvae are herbivorous, omnivorous or carnivorous.

Wells: p. 562

d. Be able to explain some of the costs and benefits of cannibalism for larval salamanders. What are some explanations for cannibalizing different species?

Wells: pp. 563-564

e. Be able to provide some examples of tadpole species that delay lung development and why this may occur.

Wells: pp. 565

f. Be able to provide some explanations why the limbs of tadpoles emerge late in development compared to salamanders.

Wells: pp. 565-566

g. Understand the mechanism that induces carnivory in spadefoots found in the southwestern United States. Also, understand how frequency of cannibalistic and omnivorous phenotypes differs between spadefoot species (S. bombifrons and S. multiplicata) and why this may occur.

Wells: pp. 575-576

h. Although most amphibian larvae are solitary, be able to provide some benefits of aggregation behavior and what may be the adaptive significance of each benefit.

Wells: pp. 588-590

i. Be able to describe the “selfish herd” effect and provide an example.

Wells: p. 589

j. Be able to describe kin recognition and offer some explanations why this may be advantageous.

Wells: pp. 591, 593-596

k. Be able to explain the factors that drive a larval amphibian to decide when to initiate metamorphosis according to Werner (1986, 1988) and Rowe and Ludwig (1986, 1988). NOTE: Your explanation should discuss differential mortality and growth rates in the aquatic and terrestrial environments and the amount of time between metamorphosis and the age of first reproduction.

Wells: pp. 601-602

l. Know what hormone likely is responsible for initiating metamorphosis in response to an environmental stressor.

Wells: p. 608

Supplemental Readings

Walsh et al. 2008: Plasticity and Metamorphosis

Petranka and Kennedy 1999: Tadpoles: Macrophagous Predators

Wells: pp. 564-566, 604-608

13) Predators, Defense, and Escape

Required Readings:

a. Why might explosive breeding be favored as a reproductive strategy in the presence of predation?

Wells: p. 696

b. Describe the tradeoffs between foraging activity and predator avoidance in larval amphibians.

Wells: pp. 704-706

c. Describe how predation may act as a selective force on growth rates of larval amphibians.

Wells: p. 708

d. Know the difference between cryptic coloration and aposematic coloration.

Wells: pp. 709-710 (cryptic) and pp. 721-724 (aposematic)

e. What are some defensive postures associated with toxic amphibians?

Wells: pp. 716-719 (Figures 14.29 and 14.30)

f. Describe the two general categories of compounds found in amphibian defensive secretions.

Wells: pp. 719-720

g. Describe the “unken reflex” as it relates to aposematic coloration.

Wells: p. 724 (also Figures 14.29 and 14.30)

Supplemental Readings

Jared et al. 2011: Amazonian toad adaptations

14) Foraging Ecology

Required Readings:

Wells (2007) and Altig et al. (2007)

a. What is the function of the hyobranchial apparatus in caecilians and aquatic salamanders (McDiarmid and Altig Handout, p. 244)

b. What is/are the major difference/s on foraging strategies between aquatic anurans, caecilians, and aquatic salamanders (Slide show, other sources)

c. What is/are the major difference/s on foraging strategies between adult anurans and its larvae (Slide show, other sources)

d. What is the ecological role of tadpoles? What happens if they are removed from an aquatic ecosystem? (Altig et al. 2007)

e. Be able to describe a few oral adaptations of larval salamanders that assist in suction feeding. Wells pp: 561-562

f. Know whether salamander larvae are herbivorous, omnivorous or carnivorous. Wells p. 562

g. Be able to explain some of the costs and benefits of cannibalism for larval salamanders. What are some explanations for cannibalizing different species? Wells pp. 563-564

Supplemental Readings:

1. Bwong and Measey 2010

2. Sih and Petranka 1988

3. Verdade et al. 2000

4. Wassersug 1972

TEST #3 Material

1) Sampling Techniques

Required Readings:

North American Amphibian Monitoring Program

· Know information in the following sections: Nightly Sampling Conditions, Data Collection (including calling index), and Placement of Stops along Routes

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)

Green et al. (2009): Disease Monitoring and Biosecurity (know information in sections 26.3 & 26)

2) 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

Supplemental Readings

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

3) Ranaviruses

Required Reading:

Gray and Miller (2013) (know all information)

Supplemental Readings:

a. Ecopathology of Ranaviruses infecting Amphibians (Miller et al. 2011)