Extraction without tooling around — The first comprehensive description of the foraging- and socio-ecology of wild Goffin’s cockatoos (Cacatua goffiniana)

Abstract

When tested under laboratory conditions, Goffin’s cockatoos (Cacatua goffiniana) demonstrate numerous sophisticated cognitive skills. Most importantly, this species has shown the ability to manufacture and use tools. However, little is known about the ecology of these cockatoos, endemic to the Tanimbar Islands in Indonesia. Here we provide first insights into the feeding- and socio-ecology of the wild Goffin’s cockatoos and propose potential links between their behaviour in natural settings and their advanced problem-solving capacities shown in captivity. Observational data suggests that Goffin’s cockatoos rely on a large variety of partially seasonal resources. Furthermore, several food types require different extraction techniques. These ecological and behavioural characteristics fall in line with current hypotheses regarding the evolution of complex cognition and innovativeness. We discuss how the efficiency of (extractive) foraging may preclude tool use in wild Goffin’s cockatoos, even though the corresponding cognitive and ecological prerequisites seem to be present.

Notes on ecology of wild goffin’s cockatoo in the late dry season with emphasis on feeding ecology

“…In terms of social structure, most species of parrots show complex social organization (Seibert, 2006) with the majority of cockatoo species studied in the wild exhibiting high sociability and little variation in their social structures (Mulawka, 2014). First insights into the social structure of wild Goffin's cockatoos are provided by field observations where individuals were observed either solitary, in pairs or in groups (Cahyadin et al, 1994a;O'Hara et al, 2018). A seemingly similar social structure was reported for a close relative (White et al, 2011), the Western Long-Billed Corella (Cacatua pastinator).…”

“…However, wild-caught Goffin's cockatoos were observed to open the fruit by removing stripes of the thick outer layer, dropping the majority of the papaya flesh, and foraging on the seeds (O'Hara et al, 2018). Alternatively, as some pieces of the flesh were also superficially digested, most likely in order to absorb the fruit juice, papaya feeding might be argued to not represent a case of "pure" extractive foraging.…”

“…Similarly, Goffin's cockatoos are able to gradually bite through the thick layer of young coconuts by removing stripes of the mesocarp, a process which might require several days to complete, in order to access the endosperm and fruit water (O'Hara et al, 2018). The cassava roots, located several centimeters underground, can be accessed by Goffin's cockatoos through continuous biting at the bottom of the plant and then gradually removing soil with their beaks in order to expose the large starch containing tubers (O'Hara et al, 2018).…”

“…However, an alternative approach suggests that tools are rarely more useful than evolved anatomical adaptations in ecological contexts faced by wild animals (Hansell & Ruxton, 2008). Indeed, tools do not seem to provide additional advantage for parrots who mostly interact with their environment through the powerful beak employed for a variety of activities including exploring, object manipulation, foraging, climbing, and even acting as an additional limb with the strong, dexterous tongue of some species used as an appendage (Lambert et al, 2018;O'Hara et al, 2018). Due to this functional flexibility, the parrot beak is often described as a "multi-purpose tool" (Huber & Gajdon, 2006;Hansell & Ruxton, 2008; see Auersperg, 2015 for a review).…”

“…Due to this functional flexibility, the parrot beak is often described as a "multi-purpose tool" (Huber & Gajdon, 2006;Hansell & Ruxton, 2008; see Auersperg, 2015 for a review). Goffin's cockatoos were observed using their beak for digging in loose soil, shovelling clumps of hardened soil, tearing thick fruit layers, removing tree bark and dismantling rotting tree trunks (O'Hara et al, 2018).…”