Archaius, Vol. 2, No. 1, 2025 

     Submitted 07.01.2025 

 Published 15.02.2025     

This report presents another case of opportunistic ornithophagy, wherein an adult male Malagasy Giant Chameleon (Furcifer oustaleti) consumed a Blue Tit (Cyanistes caeruleus). The chameleon in question is a captive-bred Hungarian F1 offspring of wild-caught parents, hatched in 2021 and raised in Gevelsberg, Western Germany. At the time of observation, the chameleon measured 51 cm in length and weighed 280 g. It is typically fed approximately 10 assorted insects weekly, which creates a constant foraging habit, as the chameleon is almost never fed ad libitum.

Maintaining chameleons in a relatively "hungry" state promotes alertness and physical activity, which are beneficial for their overall health and may positively impact their lifespan in captivity (personal observations). When ambient temperatures reach a stable 18°C during the day, the F. oustaleti is allowed to free-range in the owner's garden under supervision or is housed in a dedicated outdoor enclosure. During these periods, the chameleon has the opportunity to capture and consume a variety of insects or invertebrates that come within the striking range of its ballistic tongue.

On April 6th, 2024, the chameleon was exposed to the spring sun in a Lilac Tree (Oleaceae: Syringa vulgaris) and caught with its tongue a Blue Tit, Cyanistes caeruleus (Aves: Paridae) that was landing close to it. The bird was instantly killed due to the strong bite of the chameleon's jaw on the bird's chest and was motionless when the owner observed the scenario. The swallowing process took about 10 minutes in total, since the position of the bird within the chameleon's mouth was suboptimal, as it was holding the leg and the tail of the Blue Tit to position the prey more optimally for swallowing (Fig. 1). The bird was almost completely swallowed after 8 minutes (Fig. 2).

The weight of the chameleon before the ingestions of the Blue Tit was 334 g on April 2nd 2024. Directly after the bird was completely swallowed, the weight of the chameleon was 343 g on April 6th 2024. The weight gain is in accordance to the average weight of the Blue Tit, which is given in the range 9,7 – 12,2g (BTO 2025). Please note that here also the weight of insects, ingested in the meantime, will add on. A two week fasting period followed. After two weeks the weight dropped down to 313 g. Fecals were analysed regularly, but in contrast to the observations of Campagna Miskuff & Nečas (2020) no residues of feathers, beak or bones could be found.

The authors clearly state that this incident was unintentional and not facilitated by the owner and should not be seen as an encouragement of feeding wild birds. The Blue Tit is classified as "Least Concern" by the International Union for Conservation of Nature (IUCN 2025). In Germany, the Blue Tit is a common and widespread species, with stable populations across the country. It benefits from the availability of suitable habitats, such as mixed and deciduous forests, urban areas, and gardens. As such, there are no significant conservation concerns regarding the species in Germany at this time, despite technically, it is listed under the Federal Nature Conservation Act (2025), which provides protection for native species and their habitats. Harming or disturbing Blue Tits, their nests, or eggs is prohibited without a special permit.

This note is undermining that even captive bred and raised chameleons keep their wild instincts and will take the opportunity to catch and eat by free choice whatever looks appealing to them, even if the prey is larger than what they are normally get to eat.

Fig. 1: Observation directly after the catch (April 6th, 2024, 14:07). Furcifer oustaleti is holding the Blue Tit´s leg and tail for optimising the position to swallow it. Photo: Kathrin Rudolph.

Fig. 2: The Blue Tit is almost swallowed (April 6th, 2024, 14:15). Photo: Kathrin Rudolph.