The kea is one of six native parrot species of New Zealand . This It is olive-green parrot with bold orange-red under wing coverts is one of the few parrot species with sexual dimorphism: m M ales have longer bills and are heavier (960 g average) than females (780 g). It is endemic to the South Island where about 3000-5000 kea live in the mountain areas of southern beech (Nothofagus) forest, sub-alpine scrub and alpine grassland. No other parrot species occurs at such high altitudes throughout the whole year, even when there is snow during winter.

There they forage on more than 100 species of plants and insects: they feed on fruits and seeds from trees, bushes and grass, and nectar from flowers. They dig for roots of grass and herbs and catch insects. They feed on carcass and rubbish. About 150'000 keas were shot during the last 100 years because some keas attack and feed on live sheep. Since 1986 kea are fully protected by the government.

Compared to the kea's closest relative, the kaka, Nestor meridionalis, that inhabits lower altitude temperate forests, the kea has an extended juvenile period. After up to six months sixteen weeks of full dependence on their parents, young kea aggregate in social flocks until they form breeding pairs at the age of 4 to 5 years.

Testing social learning in the field

We conducted an experiment in which the efficiency of captive keas opening a complex food container was increased by observation of a skilled conspecific. However, only testing social learning in free ranging animals can demonstrate social learning in natural conditions. For that purpose, a tube-lifting paradigm was developed and tested on keas both in captivity and in Mount Cook National Park , New Zealand . The task was to remove a tube from an upright pole in order to gain access to a reward inside the tube. The top of the pole was higher than a standing kea so that, to remove the tube, an individual had to simultaneously climb onto the pole and manipulate the tube up the pole with its bill. Because only one naïve bird managed to remove a tube twice in 25 half-hour sessions, one bird was trained to solve the task and to provide demonstrations for others. Even under such conditions, only two of at least 15 birds learned to remove the tube in 28 sessions. There was no indication that observer birds' use of bill and feet when exploring the tube changed with increasing number of observations of tube removal in a way that would, in principle, increase the likelihood of tube removal. The results suggest a dissociation of social learning potential, as assessed in laboratory animals, and social transmission of foraging techniques in natural populations.

Social structure of kea in MT Cook Village , New Zealand

Social structure is the scaffold of social transmission of new behavior (Huffman 1996) . Social data are also relevant to evaluate alternative benefits of sociality other than social learning such as e.g. social support and to consider the relevance of each of them in the evolution of sociality in kea. For example, we observed juveniles making regurgitating behavior towards other juveniles and fledglings, because this might help individuals to overcome periods of food scarcity when their foraging skills are insufficiently elaborated. Thus, establishing a network of allies might be an important alternative to social learning, both of them being a topic of social intelligence. Whereas there are solid data about social dynamics and alliances in primates, it only recently started to be described in captive birds such as corvids. Our study is aimed at contributing some data for wild parrots. Data about presence of individual birds, agonistic interactions, play behavior, allopreening, allofeeding and hunching (soliciting food from other animals) were collected whenever they were seen in the field. Scan samples of categories of activity and nearest neighbors were also recorded. These data (for agonistic interactions more than 2000 interactions meanwhile) provide the basis for a paper we are working on about the social structure of wild kea. Until now we have little evidence for redirected aggression, or any other type of aggression involving more than two parties in kea. Nevertheless there are some indications that allies may be important especially for young keas aggregated in flocks in order to acquire a high social rank.

Molecular ecology of wild kea

So far we were had insufficient knowledge about kinship of the kea at our study site in Mount Cook National Park, New Zealand . Therefore, we collect blood samples from more then forty individuals and Drs Bruce Robertson and Neil Gemmell (School of Biological Sciences , University of Canterbury , New Zealand) are addressing two aspects of kea ecology using molecular genetic techniques: (a) the identification of sex and (b) the assessment of relatedness of individuals within two separate localities using micro satellite genotyping.

High quality genomic DNA has been extracted from blood samples taken from the keas during 2003. Drs Robertson and Gemmell have adapted avian molecular tests of sex to kea. Using polymerase chain reaction (PCR) amplification of length polymorphism at the CHD gene with two primer sets (P2/P8: Griffith et al . 1998 & CHD2550/CHD2718: Fridolfsson & Ellegren 1999). There is a male bias in sex ratio (1:1.9 males). This is consistent with male sex biases found in the other large New Zealand parrots and barring sampling bias might reflect female mortality or biased sex allocation.

Relatedness of individual kea is being assessed using seven kakapo-specific microsatellite loci, which are informative in other NZ parrots. PCR conditions for these loci have been optimized for kea and at the time of writing, genetic variation has been screened at one locus (Sha01), which displays considerable allelic variability in kea. Relatedness values will be determined for all individual pair wise comparisons from this data. Drs Robertson and Gemmell are also assessing the presence of matrilineal groups using mitochondrial DNA variation at the 5' end of the kea control region.

The Trap-Tube Problem: No Understanding for a Trap?

This experiment, originally developed by Visalberghi & Limongelli (1994), examines cognitive abilities of tool use. Studies of tool use imply an understanding of the relation between an object and its purpose or the effect caused by an action. Tool use in wild keas has not been observed yet, but due to their highly developed explorative behavior and object manipulation causal understanding of a certain degree can be assumed.

Six kea participated in the experiment and were tested individually. In a short training phase a simple transparent Plexiglas tube was used and the individuals had to use a stick (plunger) to pull the rewards towards them. In the following test we used a Plexiglas tube with a transparent trap. Rewards could only be obtained by pulling the plunger to the side without the trap.

All six keas spontaneously solved the criteria in the training phase and obtained all rewards within a few minutes. During the test sessions none of them ever acted above chance level. Apparently there was no understanding of the causal properties of the tool-trap-reward configuration. Interestingly no learning appeared in a total of 100 trials.

Since we cannot exclude the lack of understanding between the use of the object (the plunger) and its effect on the reward a test with a new apparatus was conducted. Keas could move the reward directly with their bill, but by understanding the physical properties of the trap should avoid this side. As before subjects never acted above chance level. Even when the trap was removed (thus enabling them to gain the reward by pushing it only a few centimeters when choosing this side) they showed no preference for either side. Thus kea did not understand the functional relevant features of this means-end task.

Ontogeny of neophilia and object exploration in Kea

There are radical behavioral changes between fledged, juvenile, subadult and adult keas. Chicks normally start to leave the nest and to explore the surrounding area of the nest between the 11 th and 15 th week after hatching. Juvenile, subadult and adult Keas are highly explorative and hardly neophobic, whilst fledglings show neophobic behavior in the beginning. So far little is known about the period and especially the development of the changes. Therefore, neophilia experiments were conducted with two fledgling hatched in 2003 at the Konrad Lorenz Institute for Comparative Ethology and at the zoological Garden Schönbrunn, Vienna . Known and unknown objects were presented to the subjects at different stages of ontogeny. The first one took place during nestling period (8-10 weeks after hatching), the second and the third after it had left the nest (16-19 and 20-21 week). The last one was done when the subject was about nine month old, independent off its parents and housed together with other keas. Obvious change from neophobic to neophilic behavior happened between 17 and 18 week of life. N I repeated the n eophilia experiment were repeated with older keas and e xperiments on with older keas and conducted the tube lifting and string pulling experiments were conducted with the fledglings as well in order to compare age classes. Analyses of data are in progress.