(HAR) in the zoo – Interactions with familiar and unfamiliar humans


The interactions that zoo animals have with familiar people (usually keepers) are probably both qualitatively and quantitatively different from those they have with unfamiliar people. Keepers are individually familiar because they daily spend a lot of time with the animals, and within this context a lot of interactions are possible. These may, of course, include both positive (e.g. feeding) and negative (e.g. catching for veterinary inspection) interactions. Zoo visitors, on the other hand, are individually unfamiliar because each is present for a very short period; however, it is possible that animals generalise experiences with individual visitors (and perhaps also interactions with keepers) to visitors as a whole, so that the total number of interactions with zoo visitors may be quite high. Such generalisation might be related, amongst other things, to the ease with which the animals can discriminate between different categories of people. So, to what extent are animals able to discriminate between different kinds of people, or even individual people?There is evidence from both the agricultural and the laboratory literature that animals can distinguish familiar and unfamiliar handlers. Calves, for example, behave differently towards familiar and unfamiliar handlers (Rousing et al., 2005) and towards different handlers dependent upon their previous interactions with them (De Pasille´ et al., 1996) and with their usual caretaker (Boivin et al., 1998). They can, furthermore, develop a general fear of people if subjected to rough handling, although positive handling can overcome this (De Pasille´ et al., 1996). A number of cues including clothing (Rybarczyk et al., 2003; Munksgaard et al., 1999) and facial features (Rybarczyk et al., 2001) allow them to make these discriminations. Rabbit pups also appear to be able to distinguish between people according to how much they are handled (Csata´di et al., 2007). According to Davis (2002) the ability to discriminate between humans has been shown in rats, chickens, llamas, rabbits, sheep, cows, seals, emu, rhea, penguins and honeybees. There is even anecdotal evidence that reptiles (Bowers and Burghardt, 1992) and octopus (Mather, 1992) can show discrimination between categories of people. What about animals in zoos? Hediger (1970) gives anecdotal examples of zoo animals such as tigers and shoebills Balaeniceps rex recognising and greeting their keepers, but few quantitative studies have been undertaken. Mitchell et al.’s investigations of mangabey–human interactions at Sacramento Zoo show that the animals behave differently towards keepers, observers and the public (Mitchell et al., 1991a), and also to different age/sex categories of zoo visitors (Mitchell et al., 1992b). Similarly colobus monkeys show different frequencies of human-directed behaviours towards keepers, other zoo workers and the public (Melfi and Thomas, 2005). Again, there is a need here for more research on the extent to which animals in zoos distinguish different categories of people, and how much they generalise their interactions across these categories.

Negative, positive and neutral interactions
There is a general consensus in the farm animal literature about what constitutes different qualities of interaction (Waiblinger et al., 2006; Hemsworth, 2003; Boivin et al., 2003; Rushen et al., 1999). Negative interactions can include hits, slaps, shouting and fast speed of movement (Hemsworth, 2003), and generally rough, aversive and/or unpredictable handling (Waiblinger et al., 2006). Positive interactions include feeding and petting (Boivin et al., 2003), and positive use of verbal and physical effort (Hemsworth, 2003). These are all part of the day-to-day interactions with the stockperson, and stockpeople show differences, which are related to their attitudes and personality, in whether their interactions are predominantly positive or negative (Waiblinger et al., 2002). Of course, there are other interactions which can also be aversive, for example restraint and veterinary treatment (Waiblinger et al., 2006), and which may not occur on a day-to-day basis. We know virtually nothing of how this applies in the zoo setting. One of the few empirical investigations of differences in stockperson (keepering) styles involved a comparison of three different rhinoceros keepers at Paignton Zoo (Ward and Melfi, 2004). All three keepers showed primarily positive interactions, but differed in the number of negative interactions they initiated. This was reflected in different latencies showed by the animals when required to move by the different keepers. Keeper interactions with tigers in an interactive zoo exhibit also differed between keepers and involved both positive (playing, patting) and less positive (hitting) interactions; these were related more to keeper than tiger personalities (Phillips and Peck, 2006). In the few other studies where keeper–animal interactions have been considered, negative and positive interactions have generally not been documented, but general-purpose categories of positive style have been erected, based on time spent with the animal, and/or talking to the animal (Mellen, 1991; Baker, 2004). Here, again, there is a clear need for empirical research, to establish what differences there are in keepering styles, how these relate to keeper characteristics, and what effects they have upon the behaviour (and indeed other life history characteristics: see Mellen, 1991) of the animals. We must recognise, however, that human–animal interactions in zoos are not restricted to those they have with their keepers; they are also likely to interact with other zoo personnel, contractors brought in for routine maintenance and building work, and the visiting public. There appear to be no empirical studies of human–animal interactions involving the first two categories, and very few involving the third. Mitchell et al. (1992c) investigated threats shown by mangabeys and human visitors to each other at Sacramento Zoo. Infants of both human and mangabey were rarely involved in harassment. Men and boys, however, threatened the male mangabeys significantly more than they threatened the females, and significantly more than women and girls did. This may reflect something like Hediger’s category ‘‘animals viewing humans as a conspecific’’ acting for humans as well, or it may represent something more general about human gender differences in attitudes and behaviour to zoo animals. We do not know. Not all visitor–animal interactions are so negative. Cook and Hosey (1995) showed that chimpanzees and human visitors at Chester Zoo were willing to engage in relatively long sequences of interactions which were characterised by fairly neutral behaviours such as eye contact, making noises and gestures, and begging for/ offering food. Similarly a long-billed corella (Cacatua tenuirostris) at Adelaide Zoo made great efforts to interact with humans, although unfortunately the behaviour of the humans was not recorded (Nimon and Dalziel, 1992). Thus, animals in zoos build up a history of interactions with a mixture of familiar and unfamiliar people. What sorts of relationships are set up as a result?