Colour variation in the common hamster Cricetus cricetus in the north-eastern foot-hills of the Harz Mountains

Abstract

We investigated the occurrence of colour variations in the common hamster Cricetus cricetus (Linnaeus, 1758) between 1915 and 1980 in the north-eastern foot-hills of the Harz Mountains in Saxony-Anhalt. Material was collected by a professional hamster trapper. The most frequent colour variants were white hamsters followed by piebald and yellow animals. The occurrence of colour morphs was strongly male biased. Only one black hamster, probably an atypical melanistic form, was found in the entire sample of 73 657 hamsters. Overall the percentage of variant individuals was 0.0855%. The frequency decreased significantly over the observed period. Investigations during the 1990s in a neighbouring area showed no colour variation in a smaller sample set. A possible connection between the decline in hamster numbers during this period in the study area and the reduced frequency of colour morphs is discussed.

Full text

Act a Theriolog ic a 45 (3): 377- 383 , 2 000.
PL ISS N 00 01 -705 1
Colour variation in the common hamster Cricetus cricetus
in the north-eastern foot-hills of the Harz Mountains
Anja KAYSER and Michael STU BBE
Kayser A. and Stubbe M. 2000. Colour variation in the common hamster C ricetus
cric etus in the north-eastern foot-hills of the Harz Mountains. Acta Therio logica 45:
377-383.
We investigated the occurrence of colour variations in the common hamster Cricetus
cricet us (Linnaeus, 1758) between 1915 and 1980 in the north-ea stern foot-hills of the
Harz Mountains in Saxony-Anhalt. Material was collected by a professional hamster
trapper. The most frequent colour variants were white hamsters followed by piebald
and yellow animals. The occurrence of colour morphs was strongly male biased. Only
one black hamster, probably an atypical melanistic form, was found in the entire
sample of 73 657 hamsters. Overall the percentage o f variant individuals was 0.0855%.
The freque nc y decreased significan tly over the observed period. In vestigations du ring
the 1990s in a neighbouring area showed no colour variation in a smaller sample set. A
possible conn ectio n between th e decline in hamster numbers during this period in the
stud y area and the reduced freq uency of colour morphs is discussed.
Institute o f Zoology, Martin-L uther-University Halle-Wittenberg, Dom platz 4, PF
University, D-06099 Halle/S., Germany, e-mail: kayser@zoolo gie.u ni-h alle.de
Key words-. Cricetus cricetus, colour variations, population decline, Germany
Introduction
The com mon hamster Cricetus cricetu s (Linnaeus, 1758) with its red-brow n to
grey-brown back and black belly, white patches on snout, cheeks, shoulder, upper
thigh, dorsal surface o f feet, lips and ear edges is one o f the most colou rful animal
species of the European fauna. Within this norm al coloration, considerable colou r
variations occur. A white spot on the breast is often found in the w estern distri
bu tion area, but rather infrequent in the eastern d istribution area (Niethammer
1982). Melanism is typical for Thuringia, Bashkiria and Ukraine (Zimmermann
1969, V orontsov 1982). Such black hamsters show white ear edges, feet and snout.
A single melanistic hamster was also found in the Magdeburger Borde district o f
Germ any (Weber 1973). Very dark “ atypical m e lanistic” hamsters have been
recorded from the northern foot-hills of the Harz Mountains, near Dresden and
Rheinhessen (Petzsch 1958, Thom as 1963, Zimmermann and Handtke 1968). The
colouration of these ham sters ranged from slightly darker than normal, with
occasional remnants of the normal colouration (eg light spots), to intense black.
Black hamsters without clear description are reported from Silesia, Zorbig and
other areas w hich probably belong to the same atypical melanistic form (Schlott
[377]

378 A. Kayser and M. Stubbe
1923 in Petzsch 1936, Petzsch 1939, Zimmermann and Handtke 1968). Bechstein
(1801) and later Petzsch (1949, 1950) also mentioned pure albinos, white animals
with dark eyes, yellow ones (flavistic), piebald individuals and partial albinos.
Besides white, yellow, red and black, all kinds o f intermediates like sand coloured or
“iron grey” were found (Petzsch 1950, 1960). Little information about the frequency
of colour variations is available. Only melanistic forms can accum ulate due to their
dominant inheritance pattern (Gershenson and Polevoi 1940, Petzsch 1940 in
Petzsch and P etzsch 1956). In contrast to other colou r variations, melanistic
hamsters seem to have fitness and vitality similar to norm al colou red hamsters
(Petzsch and Petzsch 1956). In the Ukraine there are areas with a melanic frequency
of over 80% (Gershenson 1945 in Vorontsov 1982, K irikov 1934 in Petzsch and
Petzsch 1956), in Thuringia up to 15% (Stengel 1932) respectively between 0.5 and
18% (Zimmerm ann 1969). The existence o f subpopulations with melanism fre
quencies up to 50% was revealed in Thuringia (Zimmermann 1969).
Other colour variations seem to be unique peculiarities. Reports date back to the
times of intensive hamster trapping and control, when the species was a serious
pest to agriculture (Muller 1956, Jiittner 1957). The present status o f the species in
central and western Europe is characterized by an enormous decline even in its
main distribution areas like the Borde region in G erm any (Seluga and Stubbe 1997,
Weidling 1997, Weidling and Stubbe 1997b).
In this study, data collected throughout his life by the ham ster trapper Richard
Marscheider from Friedrichsaue in the north-eastern foot-hills of the Harz M oun
tains at the edge of the Magdeburger Borde were analysed with regard to colo u r
variations and their frequency, and compared with the current situation.
Material and methods
Trapping records by Richard Marscheider in the area o f F riedrichsaue and neighbouring villages
between 1915 and 1980 were analysed. Altogether, he trapped 73 657 hamsters in this period. All
colour variations were recorded and, until 1942 (with the exception o f 2 years), also the sex o f the
variants. Results were compared with data from a recent hamster recapture study carried out around
the Hakel. Methods o f live trapping of comm on hamsters have been described by Weidling and Stubbe
(1997a) and Weidling (1997). The investigation areas are a short distance from each other in the
north-eastern foot-hills o f the Harz Mountains at the southern edge o f the Magdeburger Borde district
in Saxony-Anhalt, Germany. Deep chernozems to brown earth chernozems of loess and an annual
rainfall of about 500 mm are typical for this region. Regression analysis was carried out using the
program Statistica.
Results and discussion
Fr eq u en cy of colou r va r ia tio ns
In Marsche ider‘s material white, yellow, black and piebald ham sters were
recorded as colour variations com prising 0.0855% (Table 1).

Colour variation in Cricetus cricetus 379
Table 1. N umber and frequency o f colour variations in the total number of
73 657 hamsters trapped near Friedrichsaue (east Germ any) in the period
1915-1980.
Colour variation Number Frequency (%)
White 50 0.0679
Piebald 7 0.0095
Yellow 5 0.0068
Black 1 0.0014
Total 63 0.0855
The m ost frequ ent variants were white hamsters, followed by piebald and yellow
(flavistic) animals. A black hamster was found only once (in 1924), and noted as a
peculiarity. It was probably not a true melanic but a rather dark atypical form.
Nowadays these variations are also called “black” by the hamster trappers in this
region. It was impossible to identify white hamsters as true albinos or white
hamsters with black eyes (leucism ). It might be that both forms were included in
the w hite category. The term “colo u rfu l” presumably means variegated or piebald
hamsters, because the trapper specifically mentioned it as a colour variation.
A similar frequency of white hamsters (0.083%) was found in the 4800 animals
trapped in Giersleben (district Bernburg in Saxony-Anhalt) (Stubbe et al. 1998).
Weber (1973) obtained mainly albinos and flavistic hamsters, but only one black
form (typical m elanism) from hamster trappers of the district Haldensleben at the
northern edge o f the Magdeburger Borde. Flavistic hamsters were here often
accumulated around a village or a locality. Such colour variation used to be more
frequent in form er tim es in certain districts of Saxony-An halt (Petzsch and P etzsch
1956). H amster furs bought by the company Gustav Meyer from Haldensleben
(Saxony-Anhalt) included fewer piebald hamsters than white or black ham sters
(Petzsch 1936).
The frequen cy of colou r variation in M arscheider’s data is very low com pared
with oth er published information , but it is the first investigation o f such extensive
material from a restricted area over a long period. Frequencies of colour variation
were often record ed only in fur collectin g centres. Such records do not necessarily
represent th e frequency in natural populations and are often w ith out clear
tem poral or side data. For example in Austria, Bauer (1960) reported from a fur
collectin g company 0.3-1.0% atypical melanistic furs, which were twelve times
more frequent than albinotic or flav istic ones. High frequ encies of atypical
melanistic ham sters are also given by Zimmermann and Handtke (1968) for some
areas in the M agdebu rger Borde, eg 0.05% o f 4000 ham sters trapped in the village
GroB-Bornicke. T he frequency of colour variation obviously varies locally. Even
dom inantly transmitted melanism can vary considerably in frequen cy in n e igh 
bouring villages (Zimmermann 1969).

380 A. Kayser and M. Stubbe
Th e frequency o f colour variation in our data collected over 65 years is similar to
the spontaneous mutation rate o f fur colou r genes in the house mouse M us
mu scu lu s (Schlager and Dickie in Strickberger 1988). Albin otic and yellow forms
are recessive in contrast to the dominant norm al and m elanic types (Petzsch and
Petzsch 1956). The black and yellow form s belong probably to the E (Extension)
series o f the m ultiple allelomorphic system (Petzsch and Petzsch 1956, Searle
1968). T he status and genetic background o f albinism and other white and piebald
form s of Cricetus cricetus is uncertain (Petzsch and Petzsch 1956).
Se xu al differ e nce s in colou r va r ia ti on
The sex of 19 colour variations was recorded. All bu t one are males. The hamster
trapper had practised selective trapping o f males, so that about 80% males and 20%
fem ales were trapped. The frequency of the white colour variation is higher am ong
males than females (Table 2). The only black hamster from the same period was
also a male.
Data in the literature are insufficient to decide if there is really a higher
frequency of colou r variations in males.
Table 2. Sexual differences in the frequency o f the white colour variation.
Sex Number Frequency per trapped hamster
of the same sex
Females 1 0.037
Males 17 0.172
Te m por al ch an ge s o f c ol ou r var ia t io n fre que n cy
Different years were combined in five-year periods to compare the frequ ency o f
colo u r variation (Fig. 1). In the first few years only a few ham sters were trapped.
The refore the first year has been excluded from the further analysis and thirteen
five-year sets of data were obtained.
The frequency o f colou r variation decreases over the whole observed period (Fig.
2). An exception is in 1971-1975 when few ham sters were trapped because of the
population decrease. A regression analysis gives a significant red uction at the 5%
level with a correlation coefficient of r = -0.62 (Fig. 2). These data support the
observations of other trappers who report a general decrease of colou r variations,
with none in the last decades (K. Schufft, E. Minstedt pers. com m .).
On ly one male a little darker than usual was caught am ong 305 trapped
hamsters in a capture-m a rk-recapture study in the neighbouring H akel area
betw een 1994 and 1999. Its colouration was only a little bit darker than normal and
could only be recorded through direct com parison with a normal coloured hamster.

Colour variation in Cricet us cricetus 381
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1916-1921-1926-1931-1936-1941 -1946-1951-1956-1961-1966-1971-1976-
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Fig. 1. Number of colour variations (a) and total number o f trapped hamsters (b) in different five-year
periods.
Five-year period
Fig. 2. Frequency of colour variation from 1916 to 1980; regression: x = 0.308 - 0.023.y, correlation:
r = -0 .6 2 , p < 0.05.
No other colour variations were observed. It is rather unlikely that such a small
variant would have been recorded by R. M arscheider as a black hamster. Only
much darker anim als than usual are recorded by other trappers as black. This
means that no record of a real colour variant has been obtained in the nineties.

382 A. Kayser and M. Stubbe
The reduced frequency of colou r morphs in the com m on hamster in the study
area in this cen tury is correlated with the general decrease of the species in this
period. There has been not only a marked reduction o f the hamster d ensity
thro ughout its range but also a distribution regression even in the main distri
bu tion and damage area. M ost damage used to occur in Germany, especially in the
Magdeburger Borde district and the neighbouring northern and n orth-eastern
foot-hills o f the Harz Mountains (Seluga and Stubbe 1997, Stubbe et al. 1997,
Weidling and Stubbe 1997b). The fall in phenotype colour variation frequ ency may
reflect an overall loss of genetic diversity as a result of the regressive population
developm ent or a decrease of the allele frequency. Continuing genetic studies on
the remnant populations are therefore urgently required to clear this point.
Acknowledgements: We are very grateful to R. Marscheider for collecting the unique data. We w an t to
thank S. Hauer, K. Neumann and two anonymous referees for their useful comments on an earlier
version of the manuscript and K. Williams for improving the English.
References
Bauer K. 1960. Säugetiere des Neusiedlersee-Gebietes. Bonner zoologische Beiträge 11(2-4): 141-342.
Bechstein I. M. 1801. Hamster. [In: Gemeinnützige Naturgeschichte Deutschlands nach allen drey
Reichen. I. M. Bechstein, ed], Siegfried Lebrecht Crusius Verlag, Leipzig: 1005-1026.
Gershenson S. and Polevoi V. V. 1940. Inheritance of black colour in the Common hamster (Cricetus
cricetus). Comptes Rendus (Doklady) Academie o f Sciences URSS 2 9(8-9): 608-609.
Jüttner P. 1957. Hamsterschäden und Hamsterbekämpfung. Deutsche Landwirtschaft 8(4): 201 -202.
Müller K. R. 1956. Starke Hamsterschäden an Sonnenblu men. Nachrichtenblatt für den Deutschen
Pflanzenschutzdienst 10: 59-60.
Niethammer J. 1982. Cricetus cricetus (Linnaeus, 1758) - Hamster (Feldhamster). [In: Handbu ch der
Säugetiere Europas, Bd. 2/1, Rodentia II. J. Niethammer, F. Krapp, eds]. Akademische Verlags
gesellschaft, Wiesbaden: 7-28.
Petzsch H. 1936. Bemerkungen zur Melanismus- und Farbspielfrage beim Hamster. Zeitschrift für
Säugetierkunde 11: 343-344.
Petzsch H. 1939. Neue Fundnachweise von Farbspielen des Hamsters (Cricetus c ricetus L.). Zoologischer
Anzeiger 125(9/19): 269-270.
Petzsch H. 1949. Uber anomale Weißscheckung bei der Hausmaus (Mus m uscul us) und beim Hamster
{Cricetus cricetus). Mitteilungen Museum für Naturkunde und Vorgeschichte und N aturw issen 
schaftlicher Arbeitskreis 2(1): 1-8.
Petzsch H. 1950. Der Hamster. Die Neue Brehm-Bücherei, Leipzig, Wittenberg: 1-56.
Petzsch H. 1958. Erster belegter Fund eines melanistischen Hamsters (Cricetus c ricetus) aus der
Umgebung von Dresden. Säugetierkundliche Mitteilungen 6: 78-79.
Petzsch H. 1960. “ Eisengraues” Farbspiel des Hamsters (Cricetus cricetus cric etu s Linné, 1758).
Zoologischer Anzeiger 165(11/12): 418-422.
Petzsch H. and Petzsch H. 1956. Zum Problem des Vererbungsm odus für Melanismus bei dem
gemeinen Hamster (Cricetus cricetus L.) in Hinsicht auf die Evolution. Zoologischer Garten N. F.
22(1/3): 119-154.
Searle A. G. 1968. Comparative genetics of coat colour in mammals. Academic Press, London: 1-308.
Seluga K. and Stubbe M. 1997. Zur Bestandssituation des Feldhamsters (Cricetus cr ice tus L.) in
Ostdeutschland. Säugetierkundliche Informationen 21: 255-264.
Stengel E. 1932. Die Verbreitung des Hamsters und des wilden Kaninchens in Thüringen. Jenaer
Zeitschrift für Naturwissenschaften 67: 181-198.

Co lour Vari ati on in Cricetus cricetus 383
Strickberger M. W. 1988. Genetik. Carl Hanser, München, Wien: 1-843.
Stubbe M., Seluga K. and Weidling A. 1997. Bestandssituation und Ökologie des Feldhamsters Cricetus
cricet us (L., 1758). Tiere im Konflikt 5: 5-60.
Stubbe M., Stubbe A. and Weidling A. 1998. Der Feldhamster im Spiegel von Presse und Ämtern, von
Vernichtungs- und Naturschutzstrategien. [In: Ökologie und Schutz des Feldhamsters. M. Stubbe
and A. Stubbe, eds]. Wissenschaftliche Beiträge M artin-Luther-U niversitä t Halle-Wittenberg,
Halle/Saale: 333-416.
Thomas E. 1963. Melanistische Hamster, Cr icet us crice tus L., aus Rheinhessen. Zeitschrift für
Säugetierkunde 28: 43-47.
Vorontsov N. N. 1982. IFauna of the U.S.S.R. Mammals III (6)]. Nauka, Leningrad: 1-388. [In Russian]
Weber B. 1973. Erstnachweis eines Hamsters Cricetus c. cricetus L. mit typischem Melanismus für die
Magdeburger Börde. Hercynia N. F. 10: 161.
Weidling A. 1997. Zur Raumnutzung beim Feldhamster im Nordharzvorland. Säugetierkundliche
Informationen 21: 265-273.
Weidling A. and Stubbe M. 1997a. Fang-Wiederfang-Studie am Feldhamster C ricetus cricetu s L.
Säugetierkundliche Informationen 21: 299-308.
Weidling A. and Stubbe M. 1997b. Der Feldhamster - Überleben in der intensiv genutzten Agrar
landschaft. [In: Einfluss der Großflächen-Landwirtschaft auf die Fauna]. Thüringer Ministerium
für Landw irtschaft, Naturschutz und Umwelt, Erfurt: 34-37.
Zimmermann W. 1969. Die gegenwärtige Verbreitung melanistischer Hamster (C ricetus cricetus L.) in
Thüringen und Bemerkungen zu deren Morphologie. Hercynia N. F. 6: 80 -89.
Zimmermann W. and Handtke K. 1968. Atypischer Melanismus beim Gemeinen Hamster Cricetus c.
cricetus L. im Nördlichen Harzvorland und in der Magdeburger Börde. Hercynia N. F. 5: 1-6.
Received 10 M ay 1999, accepted 26 October 1999.