Southern Cassowary

Extrapolation directe à partir du rôle de disperseur exclusif documenté par la Wet Tropics Management Authority (gouvernement du Queensland) — aucune étude ne mesure directement l'arrêt de la dispersion après une disparition du casoar.

The Wet Tropics Management Authority documents that the cassowary is the only animal in Australia's tropical rainforest able to swallow whole the fruit of more than 70 tree species, too large for any other local disperser. Its disappearance would therefore mechanically — not gradually — remove the only means of carrying these seeds beyond the parent tree's shade.

What's missing to confirm it: A direct measurement of undispersed fruit accumulation following an actual cassowary disappearance, rather than an inference from its exclusive disperser role documented while it is still present.

Extrapolation à partir de Campbell et al. (2023), qui mesurent l'érosion de la fonction de disperseur natif du casoar le long d'un gradient de fragmentation forestière, sans documenter sa disparition complète.

By fitting cassowaries with an ingestible tracking device across four Wet Tropics sites with varying degrees of urbanization, Campbell et al. show that birds in the most intact forests feed almost exclusively on native fruit, while those in the most urbanized areas already pass more exotic seeds — the function degrades before the bird even disappears locally.

What's missing to confirm it: Comparable tracking in a forest where the cassowary has fully disappeared, rather than one where its presence is merely declining, to confirm the trend continues all the way to a full stop.