I

Asiatic Herpetological Research

December 1993

Vol. 5, pp. 147-165

The Ecology of the Caucasian Salamander (Mertensiella caucasica Waga) in
a Local Population

DAVID N. TARKHNISHVILI AND IRINA. A. SERBINOVA 2
1

Georgian Academy of Sciences, Tbilisi, Georgia^Moscow Zoo, 123242 Moscow, Russia'Institute of Zoology,

Abstract. -The different aspects of ecology of Mertensiella caucasica Waga, 1876 were investigated in afrom Borjomi Canyon (central Georgia) for five years (1985-1990). The aspects of thewere more precisely determined. The main fecundity is about 16.9 eggs per female.
cycle
species'
There are about 2 years in a period from egg deposition (June to first half of July) to the end ofmetamorphosis in nature. Animals have spent most of the time in shelters after metamorphosis. They
local populationlife

aappear on the ground surface at night during the breeding period. Commonly the adults don't retreat toin comparatively small plots (100-300m)
great distance from population localities. Localities are situated1189
along the streams. Estimation of adult animal number showed that the population consists ofis higher than known values of most amphibians (approaches
survival
Annualadult(1989).
specimens
Larval survival is 0.27-0.32 in the second year of life. The characteristics of demography0.77).
in localities depends mostly on subUe constitution of(especially, low renewal rates) and spatial restriction
the(which is a result of allometric growth specifics). The small recent geographical range of M.
speciescaucasica

is explained

as a result of morphological and ecological peculiarities.

General morphologicalconstitution limits adaptive possibilities of any particular representative of die European salamander tribe.

This is an explanation of quite high ecological similarity of M. caucasica and Chioglossa lusitanica.

Key Words: Amphibia, Caudata, Salamandridae, Mertensiella caucasica, Caucasus Mountains, Georgia,
population ecology.

Introduction
Natural populations are the single way of
species existence. Autoecological researchdoesn't allow a complete understanding of
the life of a species in nature.

there

That is why

must be information of life cycles,

geographical range, population size,
number dynamics, etc. On the other hand itis hard to explain ecological aspects of thespecies existence without any informationof their habitat preferences, feeding habits,

breeding sites, etc.

By analyzing connections between
species population ecology and autecology,
as well as morphology and geographicaldistribution, the most complete notion can

Investigations on someamphibian species biology have allowed
scientists to elaborate complex works
connected with different aspects of their life

be formed.

history.

A wonderful example is Bell's

works onthe

Smooth Newt (Bell and

Lawton, 1975; Bell, 1977).

There aren't many data of regular© 1993 by Asiatic Herpetological Researchstationary investigations about the ecologyof the rare or narrow-ranged species. Long
term research of such species enlarges theknowledge ofthebiologyofwide

taxonomic groups.
Moreover, theseto find out
beusefulinvestigations may
rareof
species preservation.
ways

A local population of the endemic
salamander, (Mertensiella caucasica), fromthe western Caucasus of Georgia has been
investigated for a five year period (1985This work gives additional
1990).
information about the life history of thisspecies.

The geographical distribution of the
Caucasian Salamander was mainly
established in the beginning of this century.

Information was summarized by Nikolsky(1913). Later investigations commonly
took place in earlier reported localities or in
adjacent areas.

Some new localities forsalamanders were found by Bakradze and
The real
Tartarashvili (pers. comm.).
wasM.
caucasicaofgeographic range
established. The Caucasian Salamander isAsiatic Herpetological ResearchVol. 5 p. 148

December 1993

FIG. 1. Distribution of Mertensiella caucasica.

spurs of the
Trialetian Mountain Range. Probably it is
the result of historical changes in the Kura
River bed (Fig. 1). Populations are mainly
distributed in the forest belt, but in someplaces they can be found close to subalpine
distributed

meadows.

inexternal

Humidity

locations reaches 1000

in

the

species'

mm or more per

year (another narrow-ranged representativeof the salamander tribe, Chioglossa
lusitanica, has similar requirements ofhumidity).
In the most dry part of the range of M.
caucasica, the eastern one, salamanders live
only in coniferous forest. When humidity
reaches 1200 mm/year in the middle area,
they can also be found in subalpine
meadows. Salamanders are distributed indeciduous forest only close to the BlackSea coast, where humidity is very high(2000-2400 mm/year; Fig. 1). The highdependence of the animal on humidity does
not itself limit the species distribution, but
determines sensitivity of specimens to otherenvironmental factors.

It is very

that the rheophilous species

interesting

Ranodonsibiricus, more restricted to water habitats

than M. caucasica, is geographical limitedby coniferous forests like M. caucasica ineastern localities (Paraskiv, 1953). Local
populations, distributed along tributaries of
the Chorokh and Kura rivers (in upperflow), are formed by salamanders within its
area.
is

Width of streams in salamander plots
more that 1-1.5 m in spring andnotbecause of stepped disposition of streams,
they run slowly in some places. There aremany slowly draining pools about 20-30
cm in depth with a lot of shelters. The
bottoms of streams and pools are covered
with stones, and there is a lot of nonStepped
decayed organic matter.
disposition of streams is formed by stoned
conglomerations and fallen logs.

Apparently, mountain ranges between
stream canyons don't allow widesalamander migration and local populations
are comparatively isolated. There is noevidence that direct migrations of animals
occurs during their life cycle. Individuals
are found a maximum of 200-300 m
distance from streams.

Asiatic Herpetological Research

December 1993

Vol. 5 p. 149— stream bed and branches
-*S —
and
of stones—Olarge pools where larvae were found\ — steep banks where shelters are locatedyyjfallen

trees

piles

FIG. 2. Schematic diagram of the study site for Mertensiella caucaska.
Tfie Study Area

The studied population inhabits
coniferous forest ecosystems along thesecond range tributary of the Kura River in
Borjomi Canyon (eastern part of the
The plant
species' range) (Fig. 1).
association is formed by Taxus baccate,
Picea orientalis and deciduous spots. The
size of the inhabited location is a bit morethan 200 m, and it is situated between 1000
and 1300
altitude, about 2 km from thestream mouth. Slopes are precipitous, built
by corrosion of underground tree roots ormrelatively gradual, partially coveredbypteridium, Matteuccia struthiopteris, fromthe adjoining stream banks.
There aresome stone conglomerations and fallentrees in the study area, shown on the map(Fig. 2). Air temperature is close to stream
water temperature (13-15°C in summer) in
shelters formed by stones and logs.
Dynamics of air temperature in Borjomi
Canyon in May to July, 1989 is shown in
Fig. 3. Quiet pools and shelters are relative
rare, slopes are steeper and stream flow isfaster at upper and lower localities. Densityof salamanders here falls rapidly as well asaway from the stream banks in theseplaces.

Methods
The main quantitative data were obtained
during excursions with a lantern aftersunset along the study area. The locationof each adult animal was mapped, substrate
type and distance from stream bank (moreor less than 50 cm) was recorded. Adult
animals were marked individually by toeclipping.

Combinations from clipped digits

hind-limbs (not more than 2 in 1 foot)responds to individual number of animals
from 1 to 99. Zero-1 clipped digit in thefront leg mean number of hundred. Marksof salamanders recaptured in the next year
were renewed. Data of capture-recapture
were statistically counted as in Kaughley(1977). Substrates of animals caught were
subdivided in 6 types: shallow water; sandand pebbles above water shore; wet stones;in

wet ground; moss or lichens; dry groundand stones. These types were ranked
Basicaccording to their humidity.
investigations were conducted on 8-10 and
21-23 June, 1986, 24-28 June, and 5-7.
August, 1987, 3-5 and 21-24 July, 1988,
16 June- 12 July, 1989, 2-9 July, 1990.

We had 337 contacts with males and 202
with females (including specimens found
two or more time). Recording of larvae
was conducted during night excursions.

We caught females from nature in the
reproductive period and obtained eggs
using a hormonal stimulation method(Gontcharov et al., 1989) to study someecological and morphological features of
early development. Eggs were incubated in
Weiss bowls in dechloronated water at atemperature of 14°C as well as in aquaria at

Asiatic Herpetological ResearchVol. 5 p. 150

December 1993

Date
FIG. 3. Air temperature at the Mertensiella caucasica study site during the period of reproductive activity.
Stippled bars represent periods of rainfall.

40 -i

i-

Males

Females30-

The coloration
precision of 0.1 mm.
patterns of some animals was also
recorded.

X>

S
3Results

20-

Z

10-

The niche of larvae and adult specimens.

12 3 4 YV~

i-2

5

6

Substrate
FIG. 4. Location of salamanders by substrate type.
1- shallow water; 2-

wet sand and pebbles; 3- wetstones; 4- moist ground; 5- moss or lichens; 6- drystones.

Solid bars represent males.

Stippled bars

represent females.

a temperature varying from 5-22°C. Before
completion of metamorphosis, larvae were

kept in 20 liter aquaria, where water waschanged every third day. Food consistedof crustaceans (Daphnia, Cyclops), Tubifex

and Chironomid larvae.

Morphological studies were conductedon larvae, juvenile and adult animals with abinocular magnifies and calipers. Theirsnout-vent length (L), head length (Lc),and tail length (Led) were measured with a

Salamanders don't have an even
distribution within the study site.
Preference to every substrate depends on
the amount of moisture of each particular
substrate. Frequency of captures decreases
with distance from water or potential
shelters. The number of animals capturedout of shelters depends on time and season.
Most adult specimens were recorded close
to the stream (less than 50 cm from thewater shore): 60±4% of males, 62±5% of
In contrast to data on thefemales.
ecologically similar species, Chioglossa
lusitanica (Arntzen, 1981), there is nodifference between male and female
attachment to water in M. caucasica.
Animals commonly may be found on wet
sand or stones at the water shore, and they
avoid dry soil and stones. The distributionof substrate type of captured animals for theDecember 1993

30-

Asiatic Herpetological ResearchVol. 5 p. 151

Vol. 5 p. 152

Asiatic Herpetological Research

6-

T3

D

December 1993

Asiatic Herpetological Research

December 1993

given locality. Obviously, animals
prefer places with plenty of shelters. The
mean number of salamanders captured
in aVol. 5 p. 153

states of courtship and amplexus are shown

in

Fig.

b-f.

7,

Accordingtoourwhere there were logs and wooden blocks,
combined with stone conglomerations, andobservations, sexual behavior of M.
caucasica is similar to that of Salamandra
salarnandra (Joly, 1966). The corn on thedorsal side of male tails has no special rolein courtship and amplexus. We have also
observed an attempt of copulation (Fig. 7h)
on 28 June, 1989 and 2 males in an
amplexus pose on 8 June, 1986.
Apparently, we have observed, in the latter
case, rival combats, described for S.

a lot of small pools and shelters under treeroots. The total number of adults recordedsalamandra by Kiistle (1986), but in thiswork the behavioral display is not the

1986-1990 period, including
recaptures was 455. The place where eachspecimen was found in 1989 is noted insame.

during night excursions per 10 m along thestream bank in 1986, 1987, and 1989 was
9.2 ±1.86 males and 5.26+1.13 females.
According to the "mean crowding" index of2^ -1) the mean value
Lloyd (1967) (m=m+The
respectively 21.8™ and 12.78.
inwasobserved
placeshighest density
is

for

the

Fig. 2.
realThis data could give a notion of

space distribution of animals.

Notethat larvae can be found outside of the local

population habitat significantly more often
than adults. This is connected with the factthat some of the larvae leave the shelters

Copulated females have a slightly
opened cloaca. There are more than threedays between copulation and egg
deposition. Each female deposits from 1 1
to 24 eggs (N=9, M=16.9, a=3.9). Interand intra-clutch variability of fertilized eggs
sizes

is

shown in Fig. 8.

Darevsky andand continue development in the lower
parts of the stream (see below).

Polozhikhina (1966) found that the sizes of
90 eggs found in nature ranged from 5.0-

Apparently, this process does not disturb
normal metamorphosis and juvenile animals

5.6

return to the population locality.

Activity of animals gradually
decreases after the completion of theLife Cycle.

The salamander breeding period
habitats

occurs from

in

the

observed through the transparent ventral
skin. There are well distinguished matingcorns at the adult male shoulders.
Amplexing animals were found on the
ground close to shelters. Cyren (191 1) and
Obst and Rotter (1962) described normal
sexual behavior of salamanders in water inWenatural and laboratory conditions.
observed normal sexual behavior twice: on
28 June, 1988 and 4 July, 1990. In thefirst case it took place about 2 m from thestream bank in a conglomeration of treeroots. In the second case it happened close
entrance of a rock chink.

We don't exclude the possibility of normal
For example, matingof C. lusitanica may take place both instreams and on the shore. The consequent

copulation in water.

sticking
places.

themto the substrate inshadedreproductive period.

investigatedsecond half of June until early July. Mostof the females found in July are ready foregg deposition. The large oocytes can be

to water, at themm. Females deposit separate eggs,

Egg development takes 45 days until
hatching in aquaria, where the average

When thetemperature is 14.8°C.
from
6° to 26°
changestemperature(M=16.5, o=4.7) development is extended

We can expect similar
developmental rates in nature, when thetemperature of the water is about 14-15° inJuly to August. The hatching of most partto about 48-5 1 days.

of the generation takes place not earlier thanlate

August.

Larvae found in June can bedivided into 3 groups on the basis of snout-

vent length: the I group- L=14.6-19.5mg); themmgroup- L=23.7-(M=106-180
27.5 mm (M=330-664 mg); the III groupL=29.0-35.4 mm (M=632-1400 mg). By
IIvirtue of larval size distribution, Freytag(1954) as well as Koroljov (1986)
concluded a 3 year period of larval

development in the Caucasian Salamander.
Kuzmin (1992) established no annual ringin the I and II larvae group hip bones andonly one annual ring in the III group larvae

Asiatic Herpetological ResearchVol. 5 p. 154

December 1993

YEAR 4YEAR

YEAR 2

active| embryonal development

HHH hibernationj^s hatchingloo! egg deposition

ci=i^

metamorphosis

The reproductive cycle of Mertensiella caucasica. A- underground parts of the stream bed; B- open
Csurface and temporary shelters on die ground; D- constant shelters on the ground.
water;

FIG. 9.

hip bones.

On the basis of this information

represent a single generation.

Kuzmin (1992) supposed that larvae of I
and II size groups had most probably
hatched in the given year. Nevertheless,analysis of time of reproduction andembryonic development during the year
opposes Kuzmin's opinion.
ApparenUy, salamander larvae remain in
shelters after hatching and go out whenwater temperature increases al least to 13°C
(at the beginning of the next summer).

Size differences within a generation areformed by prolonged breeding time (notonly between breeding locations [Mertens,
1968], but within populations, too) and/or
by variation of individual growth rates.
Larvae have developed during the warm
After
period of the second year.
hibernation, they have a metamorphosis in
Their
July-August of the 3rd year.

development

fromfertilized

egg

to

Lack of annual ring on hip bones can be
explained by incomplete development ofhind legs just after the hatch.
Larvaegrowth is delayed by autumn temperaturecompleted metamorphosis takes about two

Thus, animals of the I and II
size groups have a previous year hatch andthe period after metamorphosis and before

decreasing.

years in nature.

Salamanders have a concealed life during
maturity. According to Kuzmin (1992), 3-

December 1993

Asiatic Herpetological ResearchVol. 5 p. 155

5 annual rings can be observed in hip bonesof adults. Therefore, salamanders can firstbreed in the 3rd year after metamorphosis.
The total life cycle of the CaucasianSalamander from egg to egg is about 4

years (Fig. 9).

Growth and Development

Embryogenesis of M.

caucasica issimilar to other large-size egg amphibian

development(Fig.

10 a-c).

Analyzing

experimental observations, hatching takesmmplace when total length is 17-20(L=10.5-11.5 mm). When hatching starts,
a larvae has well developed externalgills
and a tail fin. Sometimes the rudiments of
3 toes can be distinguished on the hindlegs. Pigmentation is formed by a coupleof faded pigmented stripes. There are rareindividual melanophores on the surface ofthe stripes.
line of small circular non-A

pigmented patches lays along each stripe(Fig. 10 d). The gut is filled with yolk.
The total length of the smallest larva caught
in nature was at least 25 mm(commonly,
L=15 mm, minimum = 14.6 mm). Larvae

found in nature already have no yolk in thegut. Their external gills are smaller thanthose of animals that have not yet hatched.
There are 4-5 toes on the hind legs andmore pigment cells (Fig. 10 e).
Inlaboratory conditions, whentemperature is 14.8°C, yolk disappears
from the frontal part of the gut 16 days after
hatching at a length of 13.8114 mm. The
first larvae with16

a snout-vent length of 15-mm can be found in streams in early

June, but most of them appear in July.

The

small larvae, which have over wintered,appear in stream pools in small, probably

The largest group (8sibling groups.
larvae) was found on July 5, 1988.
Individual sizes in that group provides

FIG.

10.

Embryo and larval development ofMertensiella caucasica.

mm

for 70 days andthe specific growth approaches

length increases 6.27

0.24%/day.

At the same time homogeneity of generation
increases: CV=23% in June and becomes

9.9% in August. This process is probably
caused by more rapid growth and/or
comparatively high mortality of the smalllarvae.

Morphological changes, connected withof first
hibernated animals (in 1985) is shown in
the histograms of June and August larval

metamorphosis (i.e. yellow coloration of
unpigmented spots, decreasing of gill size,
reduction of tail fin- Fig. 10 f) began in
animals with at least 30 mm snout-vent
length. They approach that size in the 3rdyear of larval development. Comparing
sizes of the 2nd and 3rd year larvae, thespecific body growth rate is 0.12%/day inthe period between August and June of thenext year.
Commonly, metamorphosis

Mean total

takes place at a snout- vent length of 30-35

some information about intra-clutch larval
size

when L=17.35±0.48,
max = 19.2, coefficient ofL
7.8,
approaches

variation:

min=16.0,
variation

total=29.25±0.60,

CV=5.8%.

min=27, max=31.3,

Summer growth

size distribution (Fig.

11).

Asiatic Herpetological ResearchVol. 5 p. 156

December 1993

10

June

1

Males

5-

ru
N=10

kLixi

o-

—I
30

1

T"

40

Femalesx = 71.1

50

70

60

X>

6 = 8.4£2

SE = 2.65

10I

August

50

170 1

H
60

mi
80

L (mm)
FIG. 12. Size distribution of adult Mertensiellacaucasica in the study area. L- snout-vent length.

£
s

Z

~i

r^M

1

1

1

1

40

30

in the studied population are shown in Fig.

t~

1

50

60

1

1

70

L (mm)
FIG.

11.

Size distribution of Mertensiella

1905; Nesterov, 1911) reported that meancaucasica larvae at the study site in 1985.

L in males approached 68.9 mm (N=7) andmm. Maximal larval size approaches 35.4mm (L total=70.3 mm) in the populationof
Snout-vent
length
withinanimalsvariesthemetamorphosed
limits of 32.9-42.4 mm (body mass,
M=694-1592 mg, N=ll). At the sametime 2 larvae, with L=43.8 and 44.6 mm,studied.

are in a collection from the surroundings of

Batumi (Kuzmin, pers. comm.). Animalsof all three size groups can be foundstreams even in May (Korolyov, 1986).

inPeculiarities of natural growth of M.
caucasica are similar to C. lusitanica.
this
Althoughspeciespassesmetamorphosis at smaller sizes (i.e. L=2425 mm) their linear growth for two summer
months approaches 0.29%/day and0. 10%/day for the rest of the year (Arntzen,

1981) and it is very similar to the analogous
index of M. caucasica. The slow growth ofsalamander larvae is mainly the result of
low water temperature in streams. The
specific total length growth rate of a single
animal (from 27.9 to 56.7 mm) was
0.54%/day, and total length increased from37.0 to 59.2
was 0.42%/day underat 23-25°.
conditions,laboratorymm

The snout-vent length of adults varies
insignificantly.

12. There aren't considerable intersexual
differences in sizes and general body
proportions, but apparently females canbegin breeding at a smaller body size.
Other authors (Cyren, 1911; Knoblauch,

Data on animals measuredmm(N=ll). The animalofanbody length
outlying population(Goderdzi Mountain Pass) varies between
females, 63.5

68-77

mm in males and 56-73 mm infemales. However, our population does
not show any specifics in adult animal size
distribution.

We will briefly discuss morphologicalchanges in the period from die beginning ofactive feeding to the end of metamorphosis.
When larvae begin to feed, melanophores
gradually disperse from the lateral sides,
filling the ventral surface of the larval body.

Even the size II larval group have only anarrow non-pigmented stripe remaining on
the ventral side. All lower surface is filledby pigmented cells and non-pigmented
patches remain only on the lateral sides ofthe size III larval group. These patches areused as a substrate of xanthophores andiridiophors, forming yellow spots later on(Tarkhnishvili and Tartarashvili, 1987).

The

intensity of basic coloration iscorrelated with the size of the animal thathas already started metamorphosis. The
animals with a large size at the beginning ofmetamorphosis have a dark-brown (not as

dark as in spotted salamander) coloration
with bright and comparatively large yellow
spots. Smaller size larvae do not have such

Asiatic Herpetological Research

December 1993

Vol. 5 p. 157

an intense basic coloration and spot pattern
is more or less reduced (spots are smaller
and/or poorly expressed). The intensity ofsalamander pigmentation, like other tailed
amphibians, may vary depending on thelightintensityatthelarvallocation(Fernandez and Collins, 1988).

Ground coloration of adults varies fromto Chioglossa
lusitanica or some M. luschani subspecies(Winter et al., 1987) to dark brown. The
reddish-brown (similar

spotted pattern may be expressed in adifferent degree to full reduction (especiallyin light colored specimens) (Fig. 13).

Poorlypigmented

animalswithcomparatively reduced spots (described by
Tartarashvili and Bakradze (1989) as thesubspecies M. c. djanashvilii- Fig. 13 a)
predominate in some populations from thesurroundings of Batumi, at the Black Sea
coast. Nevertheless, dark colored animals,with well developed spots (Fig. 13 e, f)predominate in the population from thesubalpic zone (Mountain Pass Goderdzi, in
Bakradze's collection). Salamanders withan intermediate intensity of coloration are
more abundant in our studied population,
but there are some specimens with less ormore reduced spot pattern. There is also a

FIG. 13. Color variation in Menensiella caucasica.

female, colored as the form described by
Tartarashvili and Bakradze. Probable, thespecific coloration of adults is connectedwith the character of larval development,
which depends on the special climaticconditions of each habitat. That is why
many light-colored animals occur in thewarm sea cost habitat and dark colored
ones are found at high altitudes.
Populations from Borjomi Canyon are in anintermediate place. Or course, we don't
exclude the possibility of inheritable fixingof one or another coloration type in
different populations.

The Caucasian salamander is included
with the Luschan Salamander, M. luschani,in the same genus because of the tail corn,
the secondary sexual character of males(Ozeti, 1967). This character appears inandmales with a length of at least 130
it seems to be of no functional importancemm

as some investigators have proposed, forexample Cyren, (191 1).

The main changes of general body
proportion occur during ontogenetic
development. First, relative tail length
Mertens (1968)
increases after hatch.
reported this for larvae with a total length of
Based on our data,

more than 45 mm.

comparatively rapid tail growth begins at
the earliest stages of development andextends to the adult stage. On the other
hand, comparative length of head decreases
The changes of general(Fig. 14).
proportions have different intensity indifferent
stages.
developmental
Allometrical dependence of head and bodylength on the total length of the I and II sizegroup larvae is described by equations:

Lcd=0.35L 126
Lv=1.71L°- 26

The coefficients of allometric equations
for the III size group larvae is different:

Lcd=0.08L 17
Lc=1.5L°- 52'

Asiatic Herpetological ResearchVol. 5 p. 158

2.0

Spotted Salamander

December 199310

D Caucasian Salamander

1.5

Led

_L

10

Lc

0.5

J

Stage of Ontogenesis
Fig. 14. Changes in body length proportions in Mertensiella caucasica (open square) and Salamandra
salamandra (solid square) during ontogenesis. 1- larvae with total length less than 35 mm; 2- larvae withtotal length greater than 35

mm; 3- yearlings; 4- juveniles; 5- adults, solid line- L/L cc

j;broken line- 1/L C.

The coefficients of static allometricalequations for recently metamorphosed

proportion changes are common in the twothespecies (as in most Tetrapoda):

animals are:comparative

Lcd=0.23L 142
Lc=1.04L 062

lengthofhead(L/Lc)

Hence, the most rapid comparative

decreases and that of tail (L/Lcd) increases.
But in these tendencies, both are quite rapid
in M. caucasica.
In S. salamandra thechanges are gradual and moreover, tailincreasing of tail length is during late larval

length growth is poorly distinguished (Fig.

development. The comparative decreasingof head is the most rapid in the I and II size

14).

groups, but later this process isn't so clear.

Nevertheless,

it

takes

part

in

Population Number Dynamics andRegulation.

metamorphosis.
Plenty of eco-morphological features
separate M. caucasica from the otherrepresentatives of European salamander
tribe,

1967).

depended on subtilization (Ozeti,

The latter is a base determined

ecological similarity between M. caucasica
and C. lusitanica (Borja-Sanchiz and

Mlinarsky, 1979). Perhaps this is a reasonof similar breeding ways of these species
differing from other European salamanders.

The changes of general proportion of M.
caucasica and S. salamandra, which are
shown in Fig. 14, allow a comparison ofthese species. The general trends ofbody

The analysis of our 1986-1990 capturerecapture data allow us to study population

number,numberdynamics

demographic peculiarities.

andWe obtained

quite full information in 1989. In that year
the captured animal number, in relation toreal population number, was comparatively

The general picture of results ishigh.
shown in Table 1. We had 532 contacts
with animals. We met an animal twice inthe same night only on 7 occasions. They
were on the surface, essentially not
moving.

In all cases animals were captured

same plot, not more than anagainhour later. The 50 animals of 68 recaptured
in theDecember 1993

Asiatic Herpetological Research

TABLE 1. Mark-recapiure results for Mertensiella caucasica in 1989.
Date

Vol. 5 p. 159

Asiatic Herpetological ResearchVol. 5 p. 160

December 1993

used as an index of number (Bozhanski and
Semenov, 1982). We used the Jolly-Seber
method (see Caughley, 1977) to estimate
the real number of the local population andmales and 17% (OM=5.9%) of females
captured in July 1990 were marked in June
1989. Hence, survival rates of the period
from July, 1989 to July, 1990 is

dynamics during the breeding period in
1989.
The total number of breeding
animals was 1187 and the percentage ofmales was 58±0.001. The greatest numberof active animals was in the end of June.

Pm=31.8/38. 5=0.83

Females appeared a bit later than males.

0.77.

its

Unfortunately, the data of 1986-1988
don't allow us to correctly estimate thenumber of salamanders in those years. It
varied from 10-20 to 460 individuals, whenthe errors exceeded mean values, i.e.
significantly lower than real quantity. The
highest value (460) was recorded when the

Schumacher method was used on 1990
The values recorded for the 1986-

data.

1988 data didn't exceed 200. Thus, theannual number value significantly increases
when the research period is prolonged andcaptured specimen number increases. Thatis because only a smallpart of the
population

left their shelters,even in the

It should be noted that only 8
individuals (9.0±2.0%) of all 89 marked in

1986-1988 were found again in 1989. Thisquite a high number because 89

isindividuals aren't

Unfortunately, there is a lack of
information about renewal rates of tailed

amphibian populations.

Ignoring age
survival ofmaculatum
approaches 0.72
Ambystoma
for males and 0.60 for females (the mean
male number is 641 and capturing of males
is a bit more often (Husting, 1965). These
structure, the annual

for males and 0.55 for females

England(Bell,

1977).

There arelow

survival rates ofand some Anura
viridescens
Notophtalmus
when higher mortality of males is observed

considerable
lusitanica

meandata are quite similar to ours. On the other
hand, annual survival of the Smooth Newt

July.

C.

more that 10% of theadult population.

in

the

and

marked adults was 33.8±9.3% in July,
1989 and 26.2±4.2% in July, 1990.
Hence, the annual survival approachedis only 0.45

population (Arntzen, 1981) is different
because of the permanent migration of partof the population. The number of two local
populations of this species is 1236 and1324 respectively. This is similar to our
information about M. caucasica, moreover,

males

all

highest activity period in late June to early

The estimate offor

Pm= 17/28.9=0.59 for females. The part of(Ischenko,

1989).

Klewen's (1986)

quantitative data for S. salamandra showthat annual survival varies between 0.55-

0.81

(mean

investigation.

0.66

in

four

years

of

A higher female survival

the study sites have a size similar to ours.

was recorded for the genus Desmognathus

Usually, the number of animals in the
widely distributed in Europe S. salamandra
populations can exceed some thousand
Theirspecimens (Klewen, 1986).
populations are spread over several
hectares, and animals can be found far from(Husting, 1965).

The Caucasian Salamander hasathe breeding sites.

comparatively low population renewal rate,
when mortality is low. Perhaps, this kindof population dynamics is typical for
populations with low total number and high

The capture of salamanders marked inprevious years gives some information

male survival. Organ (see Husting, 1965)
mentioned that a higher male survival was a
result of significant energy expenses ofabout mortality rates of adults. Ninety
eight males and 45 females were marked in
1989.
There were 38.5%
June,(OM=7.8%) recaptured males of the total of
39 found in July 1989, and 28.9%(OM=7.3%) recaptured females of the 38
total found.
The 31.8% (OM=5.7%) of

females during breeding.

We can only indirectly estimate
salamander mortality before mating. On thebasis of adult female number and mean
fecundity, we estimate that there were
8000-9000 eggs deposited in the study site.

December 1993

Asiatic Herpetological Research

TABLE 2. Data on mark-recapture of Meriensiella caucasica from 1986 to 1988.

Vol. 5 p. 161

Asiatic Herpetological ResearchVol. 5 p. 162

condition,

especiallytemperature and

The comparative large body

December 1993

1962; Tartarashvili, pers. comm.)

wewell as of C. lusitanica delimiting these

conclude that the area of salamander
localities of high altitude and on the BlackSea coast isn't larger than ours.
Chioglossa lusitanica localities have a

species from all other Europeansalamanders is breeding by egg deposition,

similar distribution (Arntzen, 1981). On
the other hand, a small population area

when fecundity is comparatively low.

might depend on attachment to the breedingsites (stream plots suitable for egg
deposition and larval development).
Spotted salamander populations are always
distributed in significantly wider areas(Klewen, 1985).

humidity.
surface reduces

homeostatic ability.
Another main feature of M. caucasica as

The biogeographical and ecologicalM. caucasica can be
explained by consequences of its
characteristics ofOn the basis of
paleontological date, Mertensiella aff.
caucasica was distributed sympatricallywith the Spotted Salamander in an areamorphological type.

As a result of the small area of thelocalities and the lack of breeding sites, theextending to central Europe in the Pliocene.
The reduction of the range of Mertensiella
was the result of the last glacial periods

population number is limited
comparatively low level, about(Borja-Sanchiz and Mlinarsky,1979).
Nevertheless,present range of S.
salamandra is quite wide (Thorn, 1968),
while the range of M. caucasica, like otherrepresentatives of the tribe, M. luschani andequal.

C. lusitanica, is comparatively narrow andin areas with mild climate. It is unlikely

fecundity. Nevertheless, the breeding sites
are used rather efficiently.
Temporaryponds vulnerable to periodic natural

thethat the Spotted Salamander can affect theofthese species.
ofthe
Althoughgenus
Mertensiella are allopatric to S. salamandra,
C. lusitanica has a wide sympatric zone
with this species (Bas Lopez, 1984). The
absence of S. salamandra in the Caucasus,
including the Great Caucasus, obviously

geographic

range

membersThe
depends on historical reasons.
ofissubtlespeciesgeographic range
limited most of all by climatic factors.
Wolterstorff et al. (1936) mentioned thatthe range of M. caucasica has not changed
considerably since the Eocene. Perhaps thelow homeostatic ability of adults limits their

at

a

1000

individuals, when the sex ratio is close toThis amount is enough to maintaindemographically andgenetically (Lande and Barrowclough,1989). The potential population growthrate is also limited by comparatively low
thepopulations

disturbances aren't used for egg deposition.
Thus, the population renewal possibilities
of M. caucasica are different from stagnantwater amphibians. A significant part of thelatter species are not able to breed
efficiently because many of the breeding

ponds within localities are destroyed during
egg and larval development. Apparently
the egg deposition of M. caucasica is done
only in places suitable for further
development. This type of reproduction iscorrelated with the high stability of
population number though the resilience tohabitat transformation is low.

migratory possibilities.

As we already noted, the captures ofanimals far from their population locality
were very rare. The salamanders don't
penetrate the comparatively distantmountain systems like the Great Caucasus.
They also don't occur in comparatively dry
localities along the Trialeti Mountain Rangein the East (Fig. 1) where there is no relief
limit. This is one of the reasons for the

restricted salamander distribution.

On thebasis of different research (Obst and Rotter,

This described model of population
dynamics practically excludes the numberof outbursts causedby climatic
perturbations which could stimulateconsiderable migrations. Since, settling ofinvestigated species is determined by the
low tolerance of adults, the small area of

population localities and breeding sites, andthe low fecundity. Hence the main reason
for the narrow geographical range of M.
caucasica are its morphological features andthe stable type of population cycle.

Asiatic Herpetological Research

December 1993

In analyzing morphological reasons of
Caucasian Salamander ecological specifics
in comparison to related species, we can

not accept as a main character only body
proportions. Ecological particularities of all
the European salamander tribe mainly

dependon

comparatively

large

egg

formation (and probably skin structure).
These characters limit Europeansalamanders to breed only in flowing waterin comparatively wet places.

Although the European salamander
adaptive type allows comparatively wide
interspecies variability in some features, forexample coloration patterns and degree ofsubtilisation, the general morphologicalconstitution restricts adaptive ability ofparticular representatives of the group. In asense M. caucasica is a morpho-ecologicalequivalent of C. lusitanica. These species
have similar life cycle, population spatial
structure and number dynamics, climaticand biotopic preferences, etc. The central
adaptive possibility and the feature
determined place in the group can be
distinguished among a lot of morphological
There are some othercharacteristics.
features which separate these species andreveal the independent origin of both ofthem. This is, for example, tail corn inmales. Nevertheless, this structure does
not take place among main ecologicalfeatures of species and reflects only theVol. 5 p. 163

In conclusion, we would like to give an

opinion on an interesting detail connectedwith the distribution of M. caucasica.

Three anuran species, the Colchic Toad
{Bufo verrucosissimus), the CaucasianParsley frog (Pelodytes caucasicus), and
the Asia Minor Frog (Rana macrocnemis)
live sympatrically with the CaucasianSalamander.
Rana macrocnemis is
distributed all over the Caucasus. Bufo
verrucosissimus and Pelodytes caucasicus
like M. caucasica do not penetrate theeastern part of the Trialeti Mountains
because of lack of humidity. However,they are distributed in some locations in the

Great Caucasus. The northern parts of the
Trialetian and Adjaro-Imeretian mountains
are more that 50 km from the southern partsof the Great Caucasus in Central Georgia.
There are no suitable localities for forest
amphibians between these mountain
The comparatively small
systems.
transitional zone could have been crossed
many times by B. verrucosissimus and P.
caucasicus after the Great Caucasus system
was formed. If we take into consideration
the comparatively high fecundity (about
500 eggs per year for P. caucasicus andB
for
10,000
per
year
eggs
.

and

verrucosissimus)

thetemporalvariability of the breeding sites, a few
climatically favorable seasons could cause agreat increase in population number and as
result, a
According to the

a

final

massivephylogeneticalmigration.
of M.
caucasica population dynamics, we can notexpect any similar process. Hence, the lackof M. caucasica in the Great Caucasus has

characteristic

historical rather than autecological reasons.

complexity of the phylogenetical ways.

Color patterns have rarely been used in
speculations, but thisa favorable object ofThe
presence of lightadaptationists.
colored specimens in some M. caucasica
populations, their predominance in otherpopulations of this species and in M.
luschani and, finally, fully reduced ofspotted specimens in C. lusitanica are notconnected with variability of the plant coverin localities and do not affect theirisWe

can't speculate
ecological preferences.
about the adaptive meaning of coloration inthis case. Coloration is closely related tothe climate type of localities.

peculiarities

Acknowledgments
The authors wish to express their
gratitude to Dr. S. L. Kuzmin for his great
help in providing material and literature.

We also thank Mr. R. V. Tartarashvili forinteresting information and material. Dr. J.
Ilieva helped us greatly to prepare theEnglish text of this article.

Literature Cited

Apparently,

we could consider this characteristic as afixed non-adaptive reaction to temperatureand humidity changes.

ALBERS, P. H. AND R. M. PROUTY
Survivalof spotted1987.
salamanders eggs inAsiatic Herpetological ResearchVol. 5 p. 164

temporary woodland ponds of coastal Maryland.
Environmental Pollution 46(1):45-61.

December 1993

FERNANDEZ, P. J. AND J. P. COLLINS.

1988.
Effect of environment and ontogeny on color
pattern variation in Arizona tiger salamanders

ARNTZEN, J. W.

1981. Ecological observation on
Chioglossa lusitanica (Caucata, Salamandridae).
Amphia Reptilia 3/4:187-203.

(Ambystoma tigrinum nebulosum Hallowell).
Copeia 1988(4):928-938.

FREYTAG, G. E.
BAS LOPEZ, S.

Biogeographia de losamfibies y reptiles de Galicia, un ensago de
1984.

Der Kaukasus-

1954.

Salamander, ein seltener Terrarien pflegling.
Die Aquarien und Terrarien Jahrbuch:l 15-1 19.

Amphibia Reptilia 5:289-310.

sintesis.

GOLUBEV, N. S.
BELL, G. A. C.

1977.

The life of the smoothnewt (Triturus vulgaris) after metamorphosis.
Ecological Monographs 47(3):279-299.

BELL, G. A. C. AND J. H. LAWTON. 1975. The
ecology of the eggs and larvae of the smoothnewt, Triturus vulgaris (Linn.). Journal ofAnimal Ecology 44(2):393-424.

tail

1981.

[The peculiarities of the

autotomy and regeneration of the Caucasiansalamander]. Voprosy gerpetologii.
Leningrad 5:40. (In Russian).

Nauka,GONTCHAROV, B. F., O. SHUBRAVY, A.
SERBINOVA, AND V. K. UTESHEV. 1989. The
USSR program for breeding amphibians,
I.

and

rare

includingI.

endangered

species.

International Zoo Yearbook 28:10-21.

BENESKI, J. T., E. J. ZABISKO, AND J. H.
LARSEN.

1986.

Demography and migratory

patterns of the eastern long-toed salamander,

Ambystoma macrodactylum columbianum.
'

HUSTING, E. L.

1965. Survival and breeding
population of Ambystoma
maculatum. Copeia 1965(3):352-362.
structureina

Copeia 1986(2):398-408.

BOZHANSKI, A. T. AND D. V. SEMONOV.

1982.

[The data on the biology of the Caucasian(Mertensiellacaucasica)].
Zoologichesky Zhurnal 61(8): 1 1 18- 1 129. (Insalamander
Russian).

ISCHENKO, V. G. 1989. [The reproductive tactics
and demography of amphibian population].
nauki
tekhniki.
Itogi
ZoologiyaV.
17.
pozvonochnykh.
Problemy
populyatsionnoy ekologii zemnovodnykh ipresmykayushchikhsya. Moscow, VINITI:5-51.
i(In Russian).

BORJA-SANCHIZ, F. DE AND M. MLYNARSKI.
1979.
Pliocene salamandids (Amphibia,
Caudata) from Poland. Acta Zoologica Cracov
24(4): 175-188.

JOLY, J.

Sur l'ethologie sexuelle de1966.

Salamandra salamandra (L.).

Z. Tierpsychol.

23(l):8-27.

BRODIE, E. D., R. A. NUSSBAUM, AND M. Dl
GIOVANI. 1984. Antipredator adaptations ofAsiansalamanders(Salamandridae).

KASTLE, W.

1986. Rival combaLs in Salamandra
salamandra. Pp. 525-528 In Z. Rocek (ed.),Studies in Herpetology. Prague.

Herpetologica 40(l):56-68.

KAUGHLEY, G.
CYREN, O.

Beitrage zur Kenntnis der
Kaukasichen Feuer-salamanders, Salamandra
caucasica (Waga), seiner Lebensweis und1911.

Fortpflanzung.

I. S. AND V. F. POLOZHIKHINA.
1966.
[On the reproductive biology of the
Caucasian salamander- Mertensiella caucasica

DAREVSKY,

Zoologichesky Zhurnal 45(3):465-

466. (In Russian).

EKVTIMISHVILI, Z.

1948.
[Feeding of the
Caucasian salamander]. Trudy Zoologitcheskogo
Instituta
GSSR 8:239-245. (In Georgian).

AN

Analysis of vertebrate

A.

Wiley- Interscience
Publications., London, New York, Sydney,
Toronto.

361 pp.

Bericht der Senckenbergischen

Naturforschended Gesellschaft, Frankfurt a/M
42:175-189.

(Waga)].

1977.

populations.

KLEWEN, R.

1986.
Population ecology ofSalamandra salamandra terrestris in an isolated
habitat.
Z. Rocek (ed.),Pp. 395-398 In
Studies in Herpetology. Prague.

KOROLJOV, A. V.

1986.

Some data on the larvaeof Mertensiella caucasica.

Pp. 281-283 In

Z.

Rocek (ed.), Studies in Herpetology. Prague.

KUZMIN, S. L.

1992. Feeding ecology of the
Caucasian Salamander (Mertensiella caucasica)
with comments on life history.
Asiatic

Asiatic Herpetological Research

December 1993

1967.
The morphology of thesalamander Mertensiella luschani (Steindachner)
and the relationships of Mertensiella andSalamandra. Copeia 1967(2):287-298.

OZETI, N.

Herpetological Research 4:123-131.

LANDE, R. AND G. F. BARROWCLOUGH.
The

Vol. 5 p. 165

1989.

effective numbeity of population andgenetic variability and their application in the

population monitoring. Pp. 117-157 In M. E.
Sould (ed.) Viable populations for conservation.
Mir, Moscow. (Russian translation).

PARASKIV, K. P.

1953.

[Siberian salamanderAN

KazSSR,
Izvestiya
Biologicheskaya seriya 1:47-56. (In Russian).

(Ranodon sibiricus)].

Der Kaukasische

SEMLITCH, R. D. AND H. K. PEACHMANN.

Feuersalamander, Salamandra caucasica (Waga).

1985. Diel pattern of migratory activity forseveral species of pond-breeding salamanders.

KNOBLAUCH, A.

1905.

der

Berichte

Senckenbergischen
Naturforschenden Gesellschaft in Frankfurt am

Copeia 1985(1):86-91.

Main 36:89-110.

TARKHNISH VILI, D. N. AND
LLOYD, M.

1967.

Mean crowding.

Journal ofAnimal Ecology 36(1): 1-30.

Salamandridae].

MERTENS,

R.

1968.

"Normalentwicklung"zur

BemerkungendesKjaukasus-

1911. Salamandra caucasica

Izvestiya Kavkazskogo Muzuya 5:319(In Russian).

Waga.
327.

Zoologichesky Zhurnal

66(9):1328-1338. (In Russian).

Salamander].

1913. Herpetologia Caucasica.

Kantselariya Namestnika E. I. V. na Kavkaze,
272 pp. (In Russian).

Soobshcheniya

AN GSSR

133(1):177-179. (In Russian).

THORN, R.
NIKOLSKY, A. M.

V.

TARTARASHVILI, R. V. AND M. L. BAKRADZE.
1989. [The new subspecies of the CaucasianSalamanders. Salamandra 4:44^45.

NESTEROV, P. V.

R.

TARTARASHVILI. 1987. [On the development
in
of
some
spottedpigmentationd'Asieet1968. Les salamandres d'Europe,d'Afrique du Nord. Editions Paul

Lechevarier, Paris. 376 pp.

Tiflis.

OBST,

F. J.

AND J. ROTTER.

1962.

Notizen zu

Mertensiella caucasica (Waga) 1876. Aquarien
und Terrarien Zeitschrift 15(2):50-52; (3):84-86.

WOLTERSTORFF, W., L. A. LANTZ, AND W.
HERRE.

Ein Import des kaukasischen(Mertenjsiella caucasica).
Zoologischer Anzeiger 116(1/2):1-13.
1936.

Salamanders