Nesting Ecology of the Western Slimy Salamander (Plethodon albagula) from an

Abandoned Mine Shaft in Arkansasby

Stan Trauth, Department of Biological SciencesArkansas State University

Family PlethodontidaeFamily Plethodontidae(lungless salamanders)(lungless salamanders)

Largest family of salamanders (27 Largest family of salamanders (27 genera and 240 species)genera and 240 species)

Most diversity in the Nearctic (25 Most diversity in the Nearctic (25 genera),but most species are genera),but most species are Neotropical (188 species) Neotropical (188 species)

Two subfamilies (Plethodontinae and Two subfamilies (Plethodontinae and Desmognathinae) and three tribes Desmognathinae) and three tribes (Hemidactyliini, Plethodontini, and (Hemidactyliini, Plethodontini, and Bolitoglossini)Bolitoglossini)

All plethodontids possess a nasolabial All plethodontids possess a nasolabial groovegroove

The Plethodontini lack aquatic larvaeThe Plethodontini lack aquatic larvae The genus The genus Plethodon Plethodon is strictly North is strictly North

American and is represented by at least American and is represented by at least 34 species34 species

Genus Pseudoeurycea showing nasolabial groove(from Biology of Amphibians,by W. Duellman and L. Trueb)

Salamanders of the Genus Salamanders of the Genus Plethodon Plethodon in Arkansasin Arkansas

Nine species of Nine species of PlethodonPlethodon Seven species occur in the Ouachita MountainsSeven species occur in the Ouachita Mountains Of the seven, two (Of the seven, two (P. caddoensisP. caddoensis and and P.P. fourchensisfourchensis) )

are endemic to Arkansas are endemic to Arkansas Of the remaining five, three (Of the remaining five, three (P.P. albagulaalbagula, , PP. . kiamichikiamichi, ,

and and PP. . sequoyahsequoyah) are in a sibling species complex) are in a sibling species complex

RedbackSalamander,P. serratus

Caddo Mountain Salamander, Plethodon caddoensis

Fourche Mountain Salamander, Plethodon fourchensis

Rich Mountain Salamander, Plethodon ouachitae

Western Slimy Salamander, Plethodon albagula

Rich Mountain, Polk County, AR

Distribution of Plethodon species in southwestern Arkansas

David Saugey, USFS Research Biologist, at Spillway Mine

Robyn Jordan, ASU Graduate Student

Entrance to Spillway Mine

Shaft extends horizontally 148.1 m

Measuring microhabitat parameters and counting egg clutches

Aggregate of nesting female Plethodon albagula

Brooding Data in PlethodonFacts About What Is Known

1. Most data on brooding have been gleaned through behavioral studies in the red-backed salamander (Plethodon cinereus), a small eastern species.

2. The primary focus has been on brooding females that either laid and brooded eggs in the laboratory or were removed along with their egg clutches from natural nesting cavities and then were sequestered in the laboratory setting.

3. Many observations were recorded during experimental manipulation of brooding females, their egg clutches, and/or their nesting environments.

4. Brooding information on most large species of Plethodon is lacking primarily because naturally-occurring egg clutches are deposited in secluded microhabitats in areas inaccessible to researchers.

Selected Critical Data Lacking On Plethodon Nesting Ecology

1. Nesting Phenology (timing of nesting events)--Based on seasonal sampling and necropsy of females

2. Nesting Frequency (reproductive cycling--annual, biennial nesting?)--Based on seasonal sampling and gonadal examination

3. Nest Site Selection (microhabitat requirements and utilization)--Unknown for nearly all large species of Plethodon

4. Nest Characteristics (nest quality and preparation)5. Nest Site Fidelity (return to the same or different

nesting sites)6. General Brooding Behavior (territoriality, defense of

nest site or egg clutch)

Primary Objectives 1. Document nesting sites of Plethodon albagula

in an abandoned mine shaft

2. Observe and record nest site information without disturbing females and/or their egg clutches

3. Evaluate microhabitat utilization by nesting females

4. Address data regarding brooding postures and nest site fidelity

5. Experimentally manipulate females and clutches todetermine if female choice occurs between nesting site and egg clutches (indirect egg discrimination)

6. Determine the short-term effects of prescribed burning on the reproductive output in this species (2004-2006)

Brooding Posturesof Plethodon

albagula

Six Common Postures

A. Egg Clutch Encircled by Body (EEBD)B. Eggs Near or Touching

Head and Snout (ETHD)

C. Eggs Near or Touching Shoulder Region (ETSH)

D. Eggs Near or Touching Body Trunk (ETTR)

E. Eggs Near or Touching Pelvic Region (ETHP)

F. Eggs Near, Touching, or Encircled by Tail (ETTL)

*Preliminary Results

1. Brooding females yielded 101 postural observations during the three nesting seasons (1999 - 2001).

2. The most common brooding position was ETSH (34.6%, 35/101) of the time.

3. Six brooding females exhibited nest site fidelity during the 1999 and 2001 seasons.

4. Two brooding females were found at the same nesting sites during the 2000 and 2001 nesting seasons.

5. One female (R335) has returned to the same nesting site five years (1999-2003) in a row

*Trauth et al. (In press, Herpetological Natural History)

Brooding Postures of an Individual Plethodon albagulaExamined During the 2001 Nesting Season

Nesting SiteExaminationDates

A. 14 SeptemberB. 28 SeptemberC. 26 OctoberD. 30 November

Nest Site Fidelity and Annual Reproduction

(Female - L280.5)

Nov. 3, 2000 Sept. 28, 2001

Nest Site Fidelity and Annual Reproduction

(Female - R198)

Nov. 3, 2000 Sept. 14, 2001

*Egg Discrimination*Egg Discrimination Brooding females (n = 13) were presented with theirBrooding females (n = 13) were presented with their

own egg clutches (displaced 50 cm left or right) and unfamiliar egg own egg clutches (displaced 50 cm left or right) and unfamiliar egg clutches at their original nest sitesclutches at their original nest sites

Females were released at an equal distance from both egg Females were released at an equal distance from both egg clutchesclutches

After 24 hr, 9 females (69.2%) had returned to their own next sites After 24 hr, 9 females (69.2%) had returned to their own next sites and were brooding unfamiliar egg clutches.and were brooding unfamiliar egg clutches.

These results suggest that brooding females exhibit indirect egg These results suggest that brooding females exhibit indirect egg discriminationdiscrimination*Master’s Thesis – Robyn Jordan*Master’s Thesis – Robyn Jordan

Sept. 2 Oct. 6

Nov. 3 Dec. 20

L276 -2001

Sept. 2 Oct. 6

Nov. 3 Dec. 20

L275 -2001

Sept. 2, 2000

Nov. 5, 1999

Dec. 30, 1999

Sept. 14, 2001

R335

August 22, 2003Oct. 11, 2002

Sept. 13, 2002

R335

Aggressive Behavior

1 2

3 4

L325

Successful Defense of Egg Clutch

5

Female (R12) laying eggs on 13 Sept. 2002

Conclusions

1. Female Plethodon albagula exhibit at least six broodingpostures; specific postures can be maintained for prolonged periods of time.

2. 6.31% of females exhibited nest site fidelity.

3. Oviposition during consecutive breeding seasons does occur, although most females exhibit the more typicalbiennial reproductive cycle.

4. Some type of egg discrimination exists.

Acknowledgments

Dept. of Biological Sciences,Arkansas State University

United States Forest Service,Ouachita National Forest

And my graduate and undergraduatestudents