INTERNATIONAL PET ANT TRADE:
INCREASING RISK AND DANGER IN EUROPE
(HYMENOPTERA, FORMICIDAE)
A. Buschinger - Myrmecologische Nachrichten, 2004
(original title: Risiken und Gefahren zunehmenden
internationalen Handels mit Ameisen
zu Privat-Haltungszwecken (Hymenoptera: Formicidae)
English translation from Aliens, 2004)
Summary
In Europe, Austria, France, Germany, Spain and UK, for the
past few years an ever-increasing trade in pet ants has
been observed. Internet companies provide formicaries,
accessories and living ants of European origin, as well as
from overseas (South America, Indonesia, Australia).
In this article I discuss various risks of this trade: escaping
ants may establish and cause economic or biodiversity
impacts, carry diseases that switch over to indigenous
species and bastardise local faunas. Even “intraspecific”
faunal bastardisation may occur.
I suggest urging governments of all nations to ban the
trade of invertebrate species, in particular ants and exotic
species, for commercial and non-scientific purposes. Ex-
ceptional permits should only be granted when escape-
proof keeping can be guaranteed.
Introduction
During the past 2-3 years, there has been an ever-increas-
ing interest in keeping various ant species as pets at home.
In the US it is illegal to trade ant queens, however, in Eu-
rope, where restrictions are mostly lacking, a couple of
Internet-shops have established where the ant keepers can
order living ant colonies, formicaries and accessories. Since
these shops advertise and sell ants from nearly all over the
world, there is some cause for concern. Information on the
amount of this trade can be obtained from a number of
Internet forums (URLs given below). From the forums it is
also clearly recognizable that the species in question are
usually not identified, often sold under wrong names or
just with a genus name, e.g. “Pheidole sp.”, this being a
genus with 900 species worldwide, among them several
already known as major pests.
I – The risk of bastardisation of faunas
As with any intended or casual release of foreign organ-
isms in a given ecosystem, the exotic species in a few in-
stances may establish viable populations and thus
bastardise the local faunas. Even known invasive ant spe-
cies may be released in countries where they have not
been found as yet, because the dealers and customers as
laymen are unable to differentiate between hazardous and
(perhaps) harmless congeners.
Ants in particular are a greater risk to local faunas than
other exotic organisms: They are generally highly domi-
nant members in most terrestrial ecosystems. And, if re-
leased, it is usually not one or a few single specimens that
may die before having the chance to reproduce (as for
example the numerous spiders, millipedes, scorpions, man-
tids etc coming free every year). A complete ant colony,
whether escaped or set free by the keeper may find and
reorganize itself in a suitable place and, provided that
favourable ecological conditions are given, begin to re-
produce. Potential inbreeding among the progeny of a
single queen is not a serious problem in ants, as is often
erroneously believed. In any case most (potentially) inva-
sive species are polygynous and have several reproduc-
ing queens in a colony. Pet ant keepers prefer polygynous
ant species because they are believed to survive longer in
captivity. In addition, “spectacular” species are sought
after, such as the Australian bull ants (Myrmecia sp.), or
leafcutter ants (Atta and Acromyrmex spp.) and weaver
ants (Oecophyllasp.) - all offered for sale in Germany and
other European countries.
II – The risk of developing additional pest and/or invasive
ant species
Germany presently is plagued by about a dozen introduced
ant species. Most of them are confined to hot houses,
green houses of Botanical gardens, zoos etc. A few are
invading homes, hospitals, restaurants etc., among them
the Pharaoh’s ant, but also a few Pheidole species. Others
surviving in the open are the Argentine Ant (Linepithema
humile) and Lasius neglectus (Dekoninck et al 2002; see
also http://www.creaf.uab.es/xeg/Lasius/Ingles/
index.htm). Both have the potential of eradicating numer-
ous native ant species.
Most pest ants probably have arisen from widespread
synanthropic species that have been carried around the
world through traditional commerce. Pet ant keepers and
dealers are always demanding “new”, “interesting” spe-
cies. Ant collectors and dealers will hence try to bring ever
more species from nature hat never had the “chance” to be
distributed by man. Among the numerous Pheidole spe-
cies that are very popular because of their big-headed sol-
dier caste, there may be dozens of potential pest ants.
Since both dealers and customers are laymen, they are
unable to correctly identify the ant species in question.
Many are sold with evidently incorrect (nonexisting) names,
or only identified up to the genus (Pheidole, Messor and
others). Ant taxonomy is very difficult, even for the few
contemporary professional myrmecologists, and many
groups (genera) are taxonomically unsettled as yet, so it is
absolutely impossible both for dealers and customers to
assess whether or not a given species may be an actual, or
possibly future, pest.
III – The risk of ant parasites switching over to native
species
All animals carry parasites, which, if released in a foreign
habitat, may switch over to native species, threatening
them, even if the original host species cannot survive in
the new environment. These parasites may be mites, nema-
todes, protozoans, fungi, bacteria etc. Some ant species
are known to be intermediate hosts of tapeworms. In south-
ern France a Tetramoriumspecies is known to carry a tape-
worm infesting domestic fowl (genus Raillietina; Nadakal
et al1971).
As yet, extremely little has been known on the parasite
fauna of ants, but I have done some studies on tapeworms
(Buschinger 1973), on fungi (Sanchez-Peña et al. 1993),
and on gregarines, all found in ants (Kleespies et al 1997),
so I have good reason to infer that many more ant species
may carry one or other potentially dangerous parasite spe-
cies. A gregarine species found in North American,
Leptothorax ants from Montana, were able to infest Euro-
pean Leptothorax in laboratory experiments, and even the
Pharaoh’s ant. Unfortunately it did not affect this species
to an extent where its use for biological control would be
justified (Buschinger & Kleespies 1999). Though appar-
ently no incidence of such a parasite transfer among for-
eign and native ants has been recorded as yet, it neverthe-
less appears a real possibility.
IV – “Intraspecific bastardisation of fauna” – a neglected
risk
With “intraspecific bastardisation of fauna” I mean that
not only the introduction of a foreign species into a native
fauna or ecosystem may become hazardous, but also the
introduction of members of a species into distant popula-
tions of the same species. In Europe there are numerous
species with a very wide range, from Mediterranean through
sub arctic habitats. We may assume that their local popu-
lations usually have developed special adaptations to the
local climatic conditions etc. If transferred to a sufficiently
distant place they may either disappear (if they do not
tolerate the local conditions – the best case), or hybridise
with the resident population, which might weaken the
adaptiveness of the local population. Afurther problem in
this context is that expensive studies on biogeography
and phylogeography may be jeopardized.
One frequently studied question in Europe is whether a
given species has arrived from the Mediterranean refugia,
after the ice age, to the North of the Alps via the eastern or
western route. With modern DNAtechniques it is possible
to reconstruct such routes, but if (for example) an ant spe-
cies from France escapes in eastern Austria and by chance
establishes a population there, this may invalidate a lot of
research efforts.
V – URLs of Internet ant-sellers and forums
German “antstore” http://www.antstore.de (238 mem-
bers as at 15 January 2004)
German Ameisenforum http://www.ameisenforum.de
with a lot of discussions on the topic of introduction of
exotic ants. (559 members, many of them also in the antstore
forum).
France http://www.akolab.com/fourmis/forum/index.php
(in French; forum but also trading ants) (274 members)
Spain
http://www.upseros.com/comunidad/hormigas/
phpbb2/index.php (forum which doesn’t advertise ants,
but the owner sells ants on demand by e-mail) (258 mem-
bers).
Great Britain http://www.zsuk.co.uk/ presently does
not advertise ants, but has formerly sold many colonies,
e.g. leafcutter ants. Not all of the registered forum mem-
bers are ant keepers, but quite a high number are.
The German antstore in particular is importing ants from
Australia, SE-Asia, and Central America to Europe, and
also distributes ants from southern Europe in central and
northern Europe. In Germany and most European coun-
tries there is no legal restriction on the trade with exotic
animals, except for those endangered in their countries of
origin.
As yet, there is no ant species known which would be
endangered by taking them from the field in their countries
of origin. I do know only about restrictions in the USA
where trading ant queens (not workers) across borders is
illegal. The American Forum for ant enthusiasts, where
these restrictions are frequently discussed is: http://
pub8.ezboard.com/bantfarm (608 members on 15 January
2004).
VI – Conclusion
Of course, ants are not only imported by those specialised
companies, but as yet mainly by ordinary trade (with plants,
fruit, wood etc.), and also many colonies are taken home
by tourists. However, trading pet ant colonies may consid-
erably increase the numbers of imported colonies and also
of additional species, handed over to private customers -
who can be as young as 12-13 years old.
I think it would be worthwhile for IUCN (and othes) to
inform the governments of all nations on this quite recent
development, suggesting legal restrictions on exotic
arthropode trade, both because of dangers for their native
faunas and of additional invasive species whose eradica-
tion is always very expensive and nevertheless usually
fails (see fire Ants, Pharao’s ant, Argentine ant etc.)
References
Buschinger, A., 1973: Ameisen des Tribus Leptothoracini
(Hym., Formicidae) als Zwischenwirte von Cestoden.
Zool. Anz. 191, 369-380, 1973
Buschinger, A., Kleespies, R. 1999: Host range and host
specificity of an ant-pathogenic gregarine parasite,
Mattesia geminata (Neogregarinida: Lipotrophidae).
Entomol. Gener. 24, 93-104.
Dekoninck, W., C. De Baere, J. Mertens & J-P. Maelfait, 2002.
On the arrival of the Asian invader ant Lasius neglectus in
Belgium (Hymenoptera, Formicidae). Bull. Soc. roy. belg.
Ent. 138: 45-48.
Kleespies, R.G., Huger, A.M., Buschinger, A., Nähring, S.,
Schumann, R.D., 1997: Studies on the life history of a
neogregarine parasite found in Leptothorax ants from
North America. Biocontrol Science and Technology 7,
117-129.
Nadakal, A.M., A. Mohandas, K.O. John, and K.
Muraleedharan, 1971. Resistance potential of certain breeds
of domestic fowl exposed to Raillietina tetragona infections.
3. species of ants an intermediate hosts for certain fowl ces-
todes. Poultry Sci. 50:115-118.
Sanchez-Peña, S.R., Buschinger, A., Humber, R.A. 1993:
Myrmicinosporidium durum, an enigmatic fungal para-
site of ants. J. Invertebrate Pathol. 61, 90-96.
A. Buschinger
Zoological Institute,
Darmstadt University of Technology,
Schnittspahnstrasse 3,
D-64287 Darmstadt,
Germany,
Email: buschinger@bio.tu-darmstadt.de
Member of the IUCN SSC, Social Insect Specialist Group