Food presentation

The Behavioural Effects of Feed Presentation Treatments on Captive Strawberry Poison-Dart Frogs, (Dendrobates pumilio)

R. Campbell-Palmer1, C. Macdonald2 , N. Waran1
1University of Edinburgh, UK 2Royal Zoological Society of Scotland, UK

The majority of environmental enrichment studies have involved captive mammals. Global declines in amphibians have prompted increased attention towards captive breeding and reintroduction programs. Amphibian ethology and psychological requirements in captivity remains a neglected area of research. These animals are often presumed to adapt readily to captivity. However other studies suggest “limited neural complexity” and “innate education system” may render amphibians less able to adapt to captive conditions.

Feed related behaviours are highly affected by captivity, as in the wild foraging constitutes a major activity. Feeding time offers a diversion in the relatively static captive environment, however, the predictable manner in which food is often provided demands few appetitive or consumatory behaviours.

This study determined that feed presentation affected the behaviour of a population of Dendrobates pumilio, kept on public display at Edinburgh Zoo. Feeding behaviour and daily group activity was compared when frogs were presented with either a point source or enriched (“leaf”) feed technique. The leaf feed method consisted of a shallow dish covered with dried leaves that enabled the insects to hide amongst them. Food (live pinhead crickets) was retained longer in the leaf feed compared to the standard open dish feeding ( 66.84, p<0.01).

Overall feed treatment had little effect on the proportional frequencies of behaviours displayed by the group as a whole (including hiding, locomotion, vocalisation, sitting and perching). Social interactions occurred most during leaf feeding (F1,2 = 5.48, P 0.013). There was no difference in mean number of foraging individuals with feed treatment (F1,2 = 2.35, P = 0.124). Females tended to feed sooner (F1,2 = 9.63, P = 0.002), foraged more often ( = 123.95, P<0.0001) and spent longer in feed area than males, regardless of feed treatment. Duration of daily time spent in feed area was significantly increased when leaf feed was presented (F1,2 = 6.98, P = 0.001) and individual focal foraging observations determined frogs exhibited more prey-tracking behaviours. The enriched feed presentation tended to increase time intervals between prey capture events therefore making foraging more challenging, reducing rapid feeding rates and prolonging foraging activity.

Though the use of live insects is an important enrichment technique, routine point source feeding can still become predictable and unchallenging, as evident from the casual observation that many frogs tended to gather in close proximity to feed area prior to food addition. This behaviour constitutes a learnt activity that is indicative of behavioural complexity beyond simple hard-wired behaviour. This type of predictive response could provide evidence that amphibians could respond to appropriate environmental enrichment and “training” for reintroduction. Reintroduced amphibians are still faced with a low success rate. The provision of naturalistic enclosures and appropriate husbandry practices designed to target species-specific requirements could be used to increase behavioural repertoire, improve animal welfare and also raise the profile of a group which could be described as “poor exhibit animals”.

Author’s address:
C. Macdonald
Royal Zoological Society of Scotland
Edinburgh EH12 6TS
United Kingdom
e-mai :

The effect of food presentation on the mortality rates and reproductive success of a colony of Rodrigues fruit bats (Pteropus rodricensis).

S. Sanderson1, A.L. Fidgett1, C. Evans2, J. Denton2

1North of England Zoological Society, Chester Zoo, Chester, Cheshire, CH2 1LH, United Kingdom; 2School of Biological Sciences, University of Manchester, Manchester, M60 1QD, United Kingdom

The nutritional content of a diet as fed can vary dramatically from that consumed. This paper describes how a change in diet presentation – the feeding of whole versus chopped fruit thus allowing greater feed selection/discrimination – led to protein, vitamin and mineral deficiencies in a group of 50 Rodrigues fruit bats (Pteropus rodricensis). This manifested as a drop in birth rate from 79/100 adult females to 21/100 adult females, 100 % juvenile mortality and a four fold increase in adult female mortality. Adult males appeared to be unaffected. Behavioural and skeletal changes will also be described as will methods of diet evaluation and the use of ZootritionTM.

Chow, How and Wow!

Food and Feed Presentation for Primates at Edinburgh Zoo

L. McMonagle, C. Macdonald

Royal Zoological Society of Scotland, Scotland, UK

Primates display a wide range of feeding methods and feeding specialties. In order to successfully keep a range of primate species in captivity their dietary needs must be met, not only through the nutrient composition of foods but also through the opportunity to display natural feeding behaviours. This poster outlines some of the practical ways in which keepers at Edinburgh Zoo use a wide number of food-based environmental enrichment devices/techniques in order to encourage the primates to display natural feeding behaviours. Many of these methods are presented to a range of species with equal success. Other species, however, are known to have unique feeding behaviours, or needs, which require specific presentation methods to allow each individual to display these behaviours naturally.
Primate staff at Edinburgh Zoo have developed many ways of feeding those species with specific requirements so that as well as using food-based enrichment designed to encourage more general behaviours, methods designed solely to target a particular behaviour such as foraging, problem solving, tool-use, investigation, locomotion and co-ordination are employed.

Ring-tailed lemurs, Red-ruffed lemurs and Sclater’s Black lemurs
All of these species are known to adopt an inverted posture whilst feeding in the wild- suspended upside-down under the branches of their chosen feeding-site enabling them to exploit food sources above and below them. At Edinburgh we provide all of these species with, amongst other things, rope “ walkways “ as part of their enclosure furnishings. By suspending fruit such as grapes or bananas on a long, thin piece of rope from these walkways, the lemurs have to adopt the inverted posture in order to reach the food that is otherwise out of reach.

Alaotran Gentle Lemurs
Found solely in the papyrus and reed beds surrounding Lake Alaotra on Madagascar, these lemurs prefer to eat only the stems and soft pith of giant bamboo plants. They move vertically using leaping and clinging movements. The outside enclosure also has a metal grid, suspended from floor to ceiling by parallel ropes. Bamboo is then intertwined through the grid so that the animals have to maneuver down the ropes using hands and feet simultaneously, in a vertical position, as they would when feeding in the wild. The inside house is also furnished with vertical larch poles and rope. The feeding sites can be changed daily to encourage foraging and activity and the position of the ropes requires balance and agility to reach food sites in a vertical position.
One of the feeding enrichments used with the chimpanzees is the artificial termite mound. This is a concrete structure with open tubes at various positions within the mound into which items such as honey, natural yoghurt, mustard and fresh orange juice are placed. Browse such as willow branches is scattered around the enclosure. This method not only presents the chimps with a cognitive challenge to produce suitable tools but also offers them a wide range of tastes and flavours which they do not receive on a regular basis.
Allen’s Swamp Monkey
As their name suggests, these guenons live in wet, marshy habitats and have webbing between their fingers and toes. Although not deep enough for them to swim into, by floating scatter items such as sunflower seed and peanuts etc. in the water of their pool they will wade into the water to retrieve the food. Shellfish are also presented to them in this manner providing them not only with the opportunity
to actively “fish” for food but also to retrieve an important nutrient component of their diet.

Author’s address:
L. McMonagle
Royal Zoological Society of Scotland, Scotland
United Kingdom

The use of “Toy-food” in Emmen Zoo, presented in an entertaining program for zoo visitors

Zoo Emmen, the Netherlands

Zoo Emmen wishes to increase its visitors involvement in wildlife and nature in an entertaining manner. It intends to do so by providing information about nature and the environment in the widest sense of the word, hopefully stimulating visitors’ interest. Central to Zoo Emmen’s activities are its presentations of animals and plants, reflecting their natural environment as closely as possible. Visitors should learn in an entertaining manner, which will only be possible if information is presented in an attractive way.
Visitors have to be aware of the fact that animals, just like humans, need good, healthy food. The animals get their meals on a regularly basis, which is not a contribution to the reduction of unnatural behaviour in the animals. ‘Toy-food’ is therefore offered to animals in Zoo Emmen, and this phenomenon can be interesting for visitors as well.
‘Toy-food’ is given besides, or in addition to, the existing diets of the animals. The enrichment food-items have to meet following demands: (1) the animal has to work harder and longer to get the food, (2) curiosity of the animal has to be tickled, (3) behaviour like play/flight/fright/hunt/competition must be stimulated/provoked by the food offered, (4) the ‘toy-food’ may not lead to habituation, not even on a long term, (5) the offered food may not lead to scared, angry or shocked visitors. Toy-food examples are: herbs and coconuts. But also the way of presenting food items: hang food high or hide food. Use food dispensers that open irregularely at different places on different times on the outside enclosure.
An ‘infotaining’ program was developed in 2002: a powerpoint presentation about enrichment/ ‘toy-food’ (what is toy food, why do we feed toy food, toy food in relation with normal diets, safety and health), followed by guided tours where keepers show the ‘toy-food’-act.
The development of the program had four messages: (a) wake interest of visitors, (b) increase knowledge of visitors, (c) change attitude of visitors, (d) change behaviour of visitors. The program will provide visitors clarity about the idea ‘enrichment’. The powerpoint presentation is shown to adults and children, therefore it has a lot of photo’s and a short video.

· Stichting ‘De Harpij’, Verrijkingsboek, Ideeën voor gedragsverrijking van dieren in dierentuinen, 1998
· The American Association of Zoo Keepers, Inc., Enrichment Notebook, 2nd edition, 1999
· Havinga ME, Plannen van voorlichtingsprogramma’s, Werkboek blok 2.2, Voeding en preventie, Hanzehogeschool van Groningen, Groningen, 1995-1996
· Steehouder M et al, Leren communiceren, Handboek voor mondelinge en schriftelijke communicatie, derde geheel herziene druk, Wolters Noordhoff, Groningen, 1992