й 1999 by Asiatic Herpetological Research
Distribution and Natural History
of the Lidless Scinks, Asymblepharus alaicus and Ablepharus deserti (Sauria: Scincidae) in the Aksu-Djabagly Nature Reserve
(Western Tian-Shan Mountains), Kazakstan
VLADIMIR
KOLBINTZEV 1 , LARISSA MIROSCHNICHENKO 2 , AND TATJANA DUJSEBAYEVA 2
1 Aksu-Djabagly Nature Reserve,
Tjulkubas Region, South Kazakstan District 487964, Kazakstan;
2 Department of Biology, Kazak State University, Al-Farabi Pr. 71, Almaty
480078, Kazakstan
Abstract.- The data of 8
years observations on two species of the Lidless Skinks, Asymblepharus alaicus and Ablepharus
deserti from the Aksu-Djabagly Nature Reserve (Western Tian-Shan Mountains)
are analysed with special attention to geographical distribution and to some
aspects of the natural history of these lizards. It is noted
that in spite of altitude contiguity the two species form few sympatric zones
with low population density. Both species have prolongated seasonal activity,
ranging from March-April to October-November. The appearance of the skinks
after winter hibernation, their activity and the beginning of breeding season
depend on climatic conditions, slope exposition and altitude of the site.
Key
words.- Reptilia, Squamata,
Scincidae, Asymblepharus
alaicus, Ablepharus deserti, Kazakstan,
distribution, activity, breeding.
Introduction
The Aksu-Djabagly Reserve is one of the unique
natural reserves of Kazakstan. Its flora and fauna are of a great interest
because of the presence a number of endemic and localized species, as well as
of species adapted to extreme environmental conditions. The Aksu-Djabagly
Reserve occupies the western part of the Talas Alatau Range
in the Western Tian-Shan Mountains between 1100-4200 m s. l. Permanent snow level is at about 3000 m. The
climate is very continental with an average monthly temperature of -4.9 C for
the coldest month (January) and of +21.6 C for the hottest month (July). Four
basic altitudinal zones are present in the Reserve (Karmisheva, 1973; Kovschar,
Ivashzhenko, 1990). These are mountain foothill zone with a low mountain dry
steppe and xerofitic plant association; the steppe meadows, with scattered
tree-like Juniperus
forests; subalpine zoneand alpine high mountain
meadows.The relatively small territory of the Aksu-Djabagly Reserve (7400 h) is inhabited by many species typical for the zoogeographical
provinces of the Europe, North Africa and Middle Asia. Among reptiles (total number 10 species) there are two
species of the skinks , the Alpine Lidless Skink (Asymblepharus alaicus) and the Desert Lidless Skink (Ablepharus deserti).
The first species (Fig. 1) is widespreaded in the Reserve, the other israre
species of the region .
Asymblepharus
alaicus and Ablepharus deserti are of an interest from few
points. The taxonomic posi-tion Asymblepharus alaicus and Ablepharus desertiwas cleared only recently after detailed revision by Eremchenko and
Shzherbak (Eremchenko, 1981; Eremchenko a. Shzherbak, 1986) who separated the
genus Asymblepharus
and suggested an independent evolution for the two
lineages of ablepharid lizards. Data on morphology and biology of the Alpine
and the Desert Lidless Skinks are not numerous and scattered through a number
of works (Atayev, 1985; Bannikovet al., 1977; Bogdanov, 1960; 1965; Bruschko,1995;
Said-Aliyev, 1979; Shammakov, 1981; Shnitnikov,1929; Terentjev a. Chernov,
1949; Yakovleva,1964). The monograph by Eremchenko and Shzherbak (1986) deservs
special attention because it contains all known data on the morphology,
distribution and biology of the ablepharid lizards of the former USSR.
The distribution and biology of two skink species
remains poorly studied. The present paper deals mainly with the distribution of
the Alpine and the Desert Lidless Skinks in the Aksu-Djabagly Nature Reserve
and presents data on their natural history.
Material and Methods
Field observations together with the description
of live and museum material carryed out onа Asymble-pharusalaicus and Ablepharus
deserti over a period of 8 years (1988-1996) and surved as
a basis for thepresent paper. We observed and collected skinks from 22
localities of the Aksu-Djabagly Nature Reserve (Fig. 2). We
identifyied the species in the field basing on their external morphology and
altitude distribution.
Additionaly we used museum material fixed in 10 %
neutralized formalin and preserved in 70 ethanol. The
confirmation of species identification was mainly based
on the peculiarities of the scalation around the yes (see Eremchenko a.
Shzherbak, 1986). We also described character of the skink habitats together
with plant composition and visually classified the dominant substrate of the
sites. Altitudes and slope exposition were also taken
into consideration. All colonlected and museum specimens were measured in mm
according to Eremchenko and Shzherbak(1986); their
life history stages were recorded as juvenile, subadult, adult. All the skinks
captured for the present study were returned to the
sampling sites. Skink populaton density inferred by counting the numbers of
lizards active on the ground surface alonga transect and by turning over stones which were refugesover certain small square areas.
Results and Discussion
Distribution, habitats and density of the
populations - Figure2 shows 22 localities of two species examined. All the records (including museum material) weremade by the authors
themselves.
In the Aksu-Djabagly Nature Reserve the Alpine
Lidless Skink mostly inhabits the subalpine and alpine zones between 2500-3000
m where the density of the lizards is highest, particularly just on passesand
on mountain ridges. For example, on 5 August1988 we
recorded 47 specimens of Asymblepharus alaicus along the main ridge
of the Kazanchukur Range (3100 m) over an area of 50 x 50 m and overturning more than 150 stones.
During a sunny midday in July 1995 we observed 16 adult specimens in
an area of 200 x 30 m in the course of half of hour on the Ulken-Kaindy Pass
(2900 m). Transect accounting on the way down to 2400 m
revealed 8 specimens overan in area of 40 x 4 m. Using secondary ranges and
lateral splinters of the main ridge the skinks can come down to a slope as low
as 1500 m (extremely rare to1200 m) where they have very low population
density.The habitats of Asymblepharus alaicus in the
Aksu-Djabagly are very variable. There are alpine meadows scattered with
stones (Fig. 3), rocky slopes with Juniperus brush (Fig. 4) and scree slopes.
There is practically no Alpine Lidless Skink in sparse Juniperus forests. A combination of the slopes with different exposition is the
first important condition for Asymblepharus habitats because of the
possibility of using them during different times of the day. The second
essential condition is in the presence of suitable refuges represented by
bushes, screes or stone rubbles.Typical habitats for the Desert Lidless Skink
in the Aksu-Djabagly Reserve are dry south exposed slopes of no more than 2000
m in altitude (Fig. 5). As a rule, the plant community includes Ferula plant xerofitic steppe, with bushes of Rosa, Honeysucle, Cotoneaster,
Spirea scattered juniper trees (Fig. 6).However, the density of Ablepharus deserti popula-tion in the Reserve is
not high in general. Only in rare cases we observed
the lizards near human settlements. The Aksu and Djabagly rivers with their
banks of southern and northern exposure are the natural boundaries separating
the habitats of the Alpine and the Desert Lidless Skinks in the reserve. The
two species were found as sympatric in few areas only.
This occurs in the valleys of rivers flowing down a slopes having northern exposition.
In this situation around at 1200-1500 mа Asymblepharus alaicus occupies, as a rule, the river banks and Ablepharus deserti inhabitsthe
slopes having an eastern and western exposition (Fig. 7). However, both species
have here very low density.
Figure 1. The map of
the localities of the Lidless Skink in the Aksu-Djabagly Nature Reserve (Western Tian-Shan Mountains). Asymblepharus
alaicus and
Ablepharus deserti have independent enumeration:
open circles represent the localities of Asymblepharus
alaicus;
closed circles represent the localities of Ablepharus
deserti.
Asymblepharus alaicus: 1) Chuuldak (2000 m); 2)
Minzhilky Ravine (2600 m); 3) Kshy-Kaindy Pass (2200 m); 4) Kshy-Kaindy Ravine
(1850 m); 5) Ulken-Kaindy Pass (2900 m); 6) Ulken-Kaindy Ravine (2000 m); 7)
Kaskabulak (2600-3300m); 8) Aksay Pass (2900 m); 9) the Upper of the Djabagly
River (3000 m); 10) Kizolgenkol Lake (2200 m); 11)the upper of the Middle
Karasay River (3000-3100 m); 12) Low Karasay Ravine (3000-3100 m); 13)
south-western slope of Kokseky Ravine (3100-3200 m); 14) eastern slope of the
Aksay Ravine (2600 m).
аAblepharus deserti:
1)western mountain foothill of the Talas Alatau Range (1300 m); 2) Taldibulak
Ravine (1100 m); 3) northern moun-tain foothills of the Talas Alatau Range near
Djabagly Village (1200m); 4) Djabaglitau Range (1300 m); 5) valley between Aksu
and Baldabrek Rivers near the Kizilblek Village (1400m); 6) eastern slope of
the Baldabrek Ravine (1600 m); 7) mountain foothills near the Ergaly Ravine
(1200 m).
Fig. 2. Asymblepharus
alaicus.
Fig. 3. Subalpic meadow at 3000 m of altitude is a typi-cal
locality of Asymblepharus alaicus in the Aksu-Dja-baglyReserve.
Fig. 4. The locality of Asymblepharus alaicus in
theUlken-Kaindy Valley (2100 m).
Fig. 5. The locality of Ablepharus deserti in
the mouthof the Djabagly River (1200 m).
Fig. 6. View on southern slopes of the DjabaglitauRange (1500
m). The locality of Ablepharus deserti isin the background
, the locality of Asymblepharus ala-icusin the foreground.
Daily and seasonal activity
Eremchenko and Shzherbak (1986) noted that the
appearance of the skinks after winter hibernation depends on climatic
conditions, slope exposition and altitude. According to these authors, the
earliest appearance of Asymblepharus alaicus in northern Kirgizstan
was registrated on 26 March 1977 in the Kirgiz Range
(1600 m). In the mountains bordering the eastern coast of the Issik-Kul Lake
(2400 m) and on the slopes of the San-Kul-Too Range
having western exposition (2700 m) the lizards appear by late April. Yakovleva (1964)
noted an earlier activity of males in comparison with females.
Our observations on the Alpine Lidless Skink in the
Aksu-Djabagly show that lizards appear after win-ter hibernation in mid April
and, as a rule, are active untill late October-early November. On 29 October 1992 we observed some active adult specimens on the north exposed slopes at
1900 m. On 1
November 1995 skinks
were registrated on northern slope at 1300 m. For аsouthern slopes, active lizards were
recorded later. Based on data of Eremchenko and Shzherbak (1986) the last
active lizards in the Kirgiz Range (up to 3000m) were registrated on 3 November 1974. It seems the skinks have very prolonged seasonal activity. According to
Veventzev (1978) who studied Asymblepharusalaicus in the Almaty Nature Reserve
(Northern Tian-ShanMountains) some individuals were
occasionally found active during sunny days even in January-February when
small areas of ground get free of snow. On 5 August 1988
at altitude 3100 m we recorded the beginning of morning activity of the lizards
about 11:00 hrs; air temperature +13C. That low temperature
be enough for primary skink activity may shed some light on the prolonged
yearly activity of the lizards. The daily activity of the Alpine Skink from the
Aksu-Djabagly doesn't visibly differ from that of the Alpine skink, described
by Eremchenko and Shzherbak (1986) for the Kirgiz Range.These authors wrote
that in spring (April - first half of аMay)
skinks were active between 11:00-12:00 hrs and 19:00-20:00 hrs. According to
our data for summer period, these lizards appear on ground surface earlier and
are active untill 20:00-21:00 hrs. In autumn their activity shifts to the
second half of the day.
As a rule, Ablepharus deserti appears
after winter hibernation earlier than Asymblepharus alaicus because
of lower altitude of its habitats and the exclusively southern slope
expositions. In the Aksu-Djabagly the earliest record
for the beginning of Ablepharusdeserti spring activity was noted on 8 March 1989 at 1300 m. Most of the population, however, emerges from hibernation in
mid March. Kaluzhina (1951) reported that also in the Turkmenistan
the Desert Skink appears after hibernation in first half of аMarch. According to Yakovleva (1964),
in Kirgizstan lizards of this species come to the ground surface around mid March.
Paraskiv (1956) studied the Desert Skink in southern Kazakstan also noted the
first half of Marchas the time for the beginning of lizard activity. In the
Aksu-Djabagly the Desert Lidless Skink is active untill late October-early
November. The latest record here belongs to 3 November 1988. In other regions of southern Kazakstan the
skinks have the same activity pattern (Paraskiv, 1956). Yakovleva (1964) for
Kirgizia and Said-Aliyev (1979) for Tadjikistan reported late September - mid
October as theperod for winter leaving of Ablepharus deserti. The daily activity pattern of Ablepharus deserti in the Aksu-Djabagly Reserve
doesn't differ markedly from that of the Desert Skink previously described by
other authors from the surrounding territories.A visibly variable daily
activity of A.
deserti was observed by Bogdanov (1960) in Uzbekistan. For two months in
the year (March and September) skinks are active for most of the day (from 10:00-11:00 hrs to 18:00-19:00 hrs), whereas in summer they have a two-peak day activity. The first
peak occupies the time between 09:00 and 12:00
hrs. The second peak is between 17:00 and 19:00
hrs. In February and October their activity is maximal
after the midday. A two-peak activity is also typical for the Desert Skink from Kir-gizia
(Yakovleva, 1964).
All previous authors noted that juveniles and
sub-adults appear after winter hibernation earlier than adult specimens and return later to their winter refuges.
Breeding
As was first observed by Shnitnikov (1928),
viviparity is a typical feature of Ablepharus (=Asymblepharus ) alaicus. According to Yakovleva (1964), period of breeding activity of Asymblepharus alaicus in Kirgizstan occupies May-June, although some specimens copulate in July as well.
Such data contraddict to Eremchenko and Shzherbak' (1986) who registrated
frequent copulation lizards in Kirgizstan
in late March-early April. However, this contradiction couldbe a consiquence of
different climatic conditions in different years .
According to Said-Aliyev' (1979) in the southern regions of Tadjikistan the
Alpine Skink copulates in late March-April, in the northern regions in late
May-first decade of June. A single female pregnant with the eggs of 8.2 x 5.1
mm; 10.2 x 5.0 mm and 10.1 x 5.0 mm in diameter was found on 3
July1954. In the Aksu-Djabagly Reserve, we have found 5gravid females on 5 August 1988 at an altitude of 3100 m. One of these delivered 3
youngs on the next day. Some pregnant females approaching delivery we have also
observed 20
July 1995 at the Ulken-Kaindy Pass
(2900 m). On the next day the new born lizards were
met at 1900m. Based on our own data and Yakovleva's (1964) notes over a
two-month period of embryonic development of Asymblepharus alaicuswe
consider mid May - mid June as a period of copulating activity of the Alpine
Skink in the Aksu-Djabagly Reserve. As noted by previous authors
, for Ablepharus
deserti the egg-laying period varies depending on the
geographical location of the population. In Kirgizstan,
this period occupies the first decade of June (Yakovleva,1964).
In Uzbekistan, the Desert Skink lays its eggs after mid May. Paraskiv (1956) recorded
mid May - early June as optimal time for egg-laying by A.deserti in the Betpak-Dala Desert (southern Kazakstan) and in the northern
coastal territory of the Aral Sea.Unfortunately, we have no data on the
breeding season or on the clutch size of Ablepharus deserti in
the Aksu-Djabagly Reserve. However, some information on the breeding activity
of the Desert Skink inKazakstan are present in the work by Bruschko(1995), who
notes that the beginning of the breeding season depends on altitude. In the Borolday Mountains females with eggs at the last stage of the development were found from
mid May to the second half of June. For Northern
Aral Sea region Paraskiv (1956) recorded
the beginning of egg-laying by A. deserti in second the half of May. As Eremchenko and Shzherbak (1986) wrote, in Kirgizstan
the clutch sizeof the Desert Skink varies from 1 to 5 eggs
and rarely reachs 11 per female. Yakovleva (1964) recorded 2-8eggs per female
for the Kirgizstan populations. Said-Aliyev(1979) has found 10 July 1959 one
female having 3 eggs in every oveduct, the sizes of which varied from 9,1 x 3,2
mm to 11,1 x 4,1 mm in diameter. Shammakov (1981) notes 3-5 eggs in the clutch
of the Desert Skink from Turkmenistan.The lizards of both species become
sexually mature in the second year (Eremchenko a. Shzherbak,1986;
Said-Aliyev, 1979).
Enemies
According to literature data
(Eremchenko a. Shzherbak, 1986; Said-Aliyev, 1979; Yakovleva,1964) and to our
own observation, the Halys Pit Viper Agkistrodon halys , the Mountain Raser Coluber ravergieri, the Dione Snake Elaphe dione, the Steppe Ribbon Snake Psammophis lineolatum, the SteppeViper Vipera ursini and the among birds the Legger
Grey Shrike Lanius
cristatus, the Long-tailed Shrike L. schasch and the Rock Thrush Monticola saxalitis are the main enemies of both the
Alpine and the Desert Skinks in nature.
We also found skink remnants in the nests of the Black-billed Magpic (Pica pica). Kuzmina (1970) observed the Himalayan Ruby Throad (Calliope pectoralis) feeding on the Alpine Skink in the Almaty Nature Reserve.
Acknowledgments
We thank to Sergey Gryasev who helped us in the
collection of the animals. We are deeply grateful to Prof. Ilya Darevskiy
(Zoological Institute of Russian Academy of Sciences,
St-Petersburg, Russia) who commented on an early draft of this manuscript. Our
special gratitude to Prof. Emilio Balletto (University of Torino, Italy) and Mrs. Bell (United Kingdom) for their useful remarks on the manuscript and
detail correction of English.
Literature Cited
1.
Atayev, Ch. 1985. Reptiles of the Mountains of Turkmenistan. Ilym, Ashkhabad. 344 pp.
аааааа (In Russian).
2.
Bannikov, A.G., I.S. Darevsky, V.G. Ishzhenko, A.K.Rustamov and N.N.
Shcherbak . 1977. Guide to the Amphibians and
Reptiles of the Fauna of the USSR,
Prosveshcheniye, Moscow. 415
pp.
аааааа (In Russian).
3.
Bogdanov, O. P. 1960. The Fauna
of Uzbekskoyа SSR.
Amphibians and Reptiles. Tashkent. 260
pp. (In Russian).
4.
Bogdanov, O.P. 1965. The Ecology
of the Reptiles of Middle Asia . Nauka, Tashkent. 258 pp.
аааааа (In Russian).
5.
Bruschko, Z.K. 1995. The lizards of the deserts of Kazakhstan. Konzhik, Almaty. 228 pp.
аааааа (In Russian).
6.ааа Eremchenko, V.K. 1981. Systematics of Eurasian lygosomid skinks of the genera Asymblepharus
аааааа
Yeriomchenko et Szczerbak, 1980 and Ablepharus (Fitzingerin Lichtenstein, 1823) (Sauria,а
аааааа Scincidae). Pp.54-55. In Problems
of Herpetology, Abstr. All-Union Conf., Nauka, Leningrad.
аааааа (In Russian).
7.
Eremchenko, V.K. and N.N. Shzherbak . 1986. Ablepharid lizards of the fauna of USSR
andа
ааааааа adjacent countries. Ilym, Frunse. 172
pp. (In Russian).
8.
Karmisheva, N.C. 1973. The flora and vegetation of the Aksu-Djabagly Nature Reserve.
Nauka,аа
ааааааа Alma-Ata.180 pp. (In Russian).
9.
Kovshar,
A.F. and A. A. Ivashzhenko. 1990.
The Aksu-Djabagly Nature Reserve. Pp. 80-102. In
ааааааа
Sokolov, V.E., and E.E. Siroechkovskiy (eds.). Nature Reserves of Middle Asia and Kazakstan.
ааааааа Misl, Moscow.(In
Russian).
10. Kuzmina, M.A.1970. The genus Caliope.
Pp.610-618. In Dolgushin, I.A., and M.N. Korelov
(eds.). The birds of Kazakstan. Vol.
3. Alma-Ata, Nauka. (In Russian).
11. Paraskiv, K. P. 1956. The Reptiles of Kazakhstan. Academy of Sciences of Kazakhstan, Alma Ata.
аааааа 228pp. (In Russian).
12.
Said-Aliyev, S.A. 1979. The Amphibians and Reptiles of Tadjikistan. Donisch, Dushanbe. 147
pp.
аааааа (In Russian).
13.
Shammakov, S. 1981. The Reptiles of Turkmenistan. Ilym, Ashgabat. 312 pp.
ааааааа (In Russian).
14. Shnitnikov, V.N. 1928. The Reptiles of Semirechye.
Society for the study of Kazakstan,
аааааа Kizil-Orda. 85 pp.(In Russian).
15.
Terentyev, P.V. and S.A. Chernov . 1949. Field guideof the reptilians and amphibians.
Sovetskaya
аааааа Nauka, Moscow. 340 pp. (In Russian).
16. Yakovleva, I.D. 1964. The Reptiles of Kirgisia. Frunse.
272 pp. (In
Russian).
17.
Veventzev,
V. 1978. On the
ecology of Asymblepharus
alaicus in the Almaty Nature Reserve. Pp.
аааааа
15-21. In The book of scientific works of the
students of Kazak Paedagogical Institute. Almaty.
аааааа (In Russian).
