So far, the literature contains only little information on the feeding ecology of the Elongated Tortoise Indotestudo elongata (Blyth, 1853). The species is known to be omnivorous, feeding on miscellaneous plants such as herbaceous leaves, flowers, fruits and fungi, as well as on animal proteins in the form of slugs, worms and insects (Nutpand 1979; Ernst & Barbour 1989; Moll 1989; Manthey & Grossmann 1997). Das (2010) described the species as primarily herbivorous, with a diet comprising leaves, flowers, and fruits, but also fungi, dead animal matters and slugs. So far only Platt et al. (2001) conducted a more detailed investigation on the feeding ecology of I. elongata in the wild viz. in Myanmar: one scat predominantly contained remains of grass and traces of leaves and mushrooms, the second scat contained exclusively mushrooms. Furthermore, the authors reported on observations of local hunters, according to whom the tortoises also fed on fallen flowers (Dolichandrone spathacea, Milletia brandisiana, Markhamia stipulata), fruits of Olax scandens, flowers and foliage of Allium spp., and at the beginning of the wet season also on grass sprouts. Probably as a natural source of calcium, I. elongata was observed to consume egg shells of the Red Jungle fowl Gallus gallus (Platt et al. 2001).

The Kulen Promtep Wildlife Sanctuary is a 400.000 ha protected area in the Northern Plains of Cambodia. The actual study area, at an elevation of only 50 m above sea level, is covered by open dipterocarp,

deciduous forests consisting mostly of members of the family Dipterocarpaceae and Tectona grandis, with an under storey of grass and scattered scrub. Large areas of grasslands and bamboo forests are present as well. In July 2009, 30 I. elongata, rescued from the illegal trade, were released, ten of which were fitted with radio transmitters (Ihlow, in preparation). The tortoises were tracked for five months during both the rainy and the dry season but only little of the daily activity of this crepuscular species was covered. During this time, some direct observation on the feeding ecology could be made.

The Cat Tien National Park covers 71,920 ha of both evergreen and deciduous lowland forests (100 m to 300 m above sea level). It is located in Dong Nai Province in southern Vietnam. During a herpetological field survey in August 2008 (Geissler, 2010), an adult female I. elongata was discovered within a dipterocarp forest. During the handling a faecal sample was collected for content analysis.

During the study in Kulen Promtep Wildlife Sanctuary, three of the ten tagged tortoises were observed several times to feed on live Quantula striata, a land snail species (see Fig.1) that is common in lowland

Herpetology Notes, volume 5: 5-7 (2012) (published online on 14 January 2012)

Observations on the feeding ecology of Indotestudo elongata (Blyth, 1853) in the wild in Cambodia and Vietnam

Flora Ihlow1*, Peter Geissler1*, Sothanin Sovath2, Markus Handschuh3 and Wolfgang Böhme1

1 Zoologisches Forschungsmuseum Alexander Koenig, Adenauerallee 160, D-53113 Bonn, Germany;

2 Department of Nature Conservation and Protection, Ministry of Environment, Phnom Penh, Cambodia;

3 Angkor Centre for Conservation of Biodiversity, Kbal Spean, Phnom Kulen National Park, Siem Reap Province, Cambo-dia;

* Corresponding authors: nc-ihlowfl@netcologne.de, pgeissler84@yahoo.de

Figure 1. Indotestudo elongata feeding on the snail species Quantula striata in the Kulen Promtep Wildlife Sanctuary in northern Cambodia. Photo: F.Ihlow.

Flora Ihlow et al. 6

deciduous forests in Indochina and peninsular Malaysia and which is also known to be consumed by various birds and mammals (Barker 2004). According to own observations Quantula striata is quite abundant in the Cambodian lowlands during the rainy season. These thin-shelled snails were eaten as a whole including their shell, probably as a source of both protein and calcium.

However, the tortoises were not observed feeding on the numerous empty shells available which indicates that the need for protein may be the main reason why the tortoises feed on these snails. In addition, we were able to observe one specimen feeding on small individuals of another, so far unidentified, land snail species (see Fig.2). Larger individuals of this second species were not consumed, probably due to the tortoises’ inability to crack the thick shells. During the rainy season one individual was observed twice feeding on common earthworms when these came to the surface in high numbers when raining (see Fig.3). Another individual was observed once feeding on a heavily decomposed skull of Viverra cf. zibetha (see Fig. 4).

Additionally, fruiting bodies of two unknown species of mushroom, probably belonging to the families Lepiotaceae and Pluteaceae, were consumed during the rainy season. The scat from Cat Tien consisted of

Figure 2. Unidentified land snail species consumed by Indotestudo elongata in the Kulen Promtep Wildlife Sanctuary in northern Cambodia. Photo: F. Ihlow

Figure 3. Numereous earthworms emerging from the ground in the Kulen Promtep Wildlife Sanctuary in northern Cambodia. Photo: F. Ihlow.

Figure 4. Indotestudo elongata feeding on a skull of Viverra cf. zibetha in the Kulen Promtep Wildlife Sanctuary in northern Cambodia. Photo: F. Ihlow.

Figure 5. Vietnamese ricefield crab Somanniathelphusa spp. Photo: P. Geissler.

Feeding ecology of Indotestudo elongata 7

the remains of two Ricefield Crabs Somanniathelphusa spp. (see Fig. 5). At the beginning of the wet season these crabs are abundant around the seasonal ponds and on the forest floor (Ng, 1988). It is unknown if the tortoises consume these crabs for their proteins or also as a source of calcium. From the remains of the crab it was also impossible to ascertain whether the crab in fact was captured or, most probable, merely the carcass was consumed. Thus, our observations suggest that food items consumed by I. elongata vary according to their seasonal availability.

Acknowledgements. We cordially thank Rainer Hutterer (Bonn), Maximilian Boecker (Dattenberg), Jasmin Obholzer (Bonn) and Christoph Schubart (Regensburg) for their kind help in the identification of the various food items. Furthermore we thank Thomas Ziegler for reviewing this paper. PG gratefully acknowledges Tran Van Thanh (Bien Hoa), Le Xuan Canh and Ta Huy Thinh (Hanoi) for supporting the herpetological field work in Cat Tien National Park. FI is indebted to Hugo Rainey (WCS Cambodia Program) for his support.

References

Barker, G.M. (2004): Natural enemies of terrestrial molluscs. CAB International Publishing, Wallingford, 445 pp.

Das, I. (2010): A Field Guide to the Reptiles of South-East Asia. New Holland Publishers Ltd, Great Britain, 376 pp.

Ernst, C.H., Barbour, R.W. (1989): Turtles of the world. Smithso-nian Institution Press, Washington DC, 314 pp.

Geissler, P. (2010): Zur Diversitätsverteilung, Biogeographie und Ökologie der Herpetofauna verschiedener Waldgebiete im Cat Tien Nationalpark in Südvietnam, unpublished diploma thesis, ZFMK, Germany, 202 pp (in German).

Manthey, U., Grossmann, W. (1997): Amphibien & Reptilien Südostasiens. Natur und Tier - Verlag, Münster Germany, pp. 456-457.

Moll, E.O. (1989): Indotestudo elongata, elongated tortoise. In: Swingland, I.R., Klemens, M.K. (Eds.): The Conservation Bi-ology of Tortoises. Occas. Pap. IUCN Species Survival Com-mission, No. 5. IUCN Publ., Gland, Switzerland: 116-117.

Ng, P.K.L. (1988): The freshwater crabs of peninsular Malaysia and Singapore. Department of Zoology, National University of Singapore, Shinglee Press, Singapore, 156 pp.

Nutphand, W. (1979): The Turtles of Thailand. Bangkok: Siam-farm Zoological Gardens, 222 pp.

Platt, S.G., Khaing, S.T., Ko, W.K., Kalyar (2001): A Tortoise sur-vey of Shwe Settaw Wildlife Sanctuary, Myanmar, with notes on the ecology of Geochelone platynota and Indotestudo elon-gata. Chelonian Conservation and Biology 4: 172-177.

Accepted by Alexandru Strugariu