Enrichment Techniques

• Enrichment for tortoise and turtles - The following techniques have been found to work well:- Live shrimps in the pool for box turtles, Live locust feed for box turtles – increases activity and turtles have been observed working together to obtain locusts, i.e. one turtle will catch and just hold the locust whilst another will eat it with relative ease as it’s clamped in its mate’s jaw. We also use wild food – in the summer offering the tortoises as much natural food as possible. This ranges from browse such as the usual willow and cherry branches to a variety of weeds like thistle, dandelion and grasses. The larger species, such as African spurred and leopard tortoises will tackle even the spiniest of thistles.
  Whole food items are also used depending on the size of species all the tortoises are offered whole vegetables or half cut, this not only makes food last longer but also keeps their beaks trim.
  Tropical tortoises, i.e. yellow-footed tortoises and Home’s hinged-back tortoises are sprayed daily with water. This has been found to increase activity particularly in the warmer months.
  Home’s hinged-back tortoises are given leaf litter substrate, which encourages foraging as these tortoises naturally eat grubs and tiny insects on the forest floor in the wild. They will also enjoy burying themselves in it.
  

• Enrichment for Lizards - We use canopy branching for green iguanas. This is particularly successful in the summer when a variety of browse is available. We have used poplar, lime, willow and cherry. Not only does this give the iguanas a choice of food, it provides them with privacy, more branching to explore and it creates a more natural smell in the enclosure. We spray the branching daily to prolong its life.
  
  We vary feeding areas regularly. The iguanas seem to get used to being fed in one position so by offering food in different areas it becomes more interesting.
  
  We also scent enclosures such as for the Nile Monitors prior to feeding, as we do with the snakes.
  
  We also hide the monitors food. This works well as it encourages them to climb and use their limbs to obtain food. Wigwams that we have built are used to place food inside.
  
  Live insect food is also used. Locust have been found to work best and dramatically increase activity. The monitors will still search for insects long after they have all gone.
  
  Rotten logs in enclosures have been found to work wellwith juvenile monitors that are more insectivorous than the adults. Monitors will spend a great deal of time in the logs looking for grubs and in most cases the logs were destroyed.

• Enrichment for Snakes - Quite possibly the hardest of all reptiles to enrich due to the fact that they will sleep 16 hours a day and if digesting a meal may sometimes lay motionless for days. There are, however, forms of enrichment that we have tried.
  
  Scenting around the enclosure prior to feeding increases activity in the snakes.
  
  Offering hiding places around the enclousre using soil and down pipes as well as hollowed out logs. Canopy branching, has also been used. It is best for arboreal species, such as the Madagascan tree boa. Not only does it provide snakes with more natural surrounding and interesting smells, it also encourages them to climb more. They appear to feel safer amongst foliage and are actually more visible for visitors. Branches used include willow, eucalyptus and poplar. The only disadvantage is that the foliage tends to dry out quickly and needs replacing regularly.
  
  All of our snakes are fed from long canes or tongs, most are fed dead rodents. With all the species we try and make their feeding as exciting as possible by simulating live prey. This is simply done by shaking the food item to encourage the snake to strike but also once taken to still fight with the food to get the snake to constrict its prey.
  
  

• Enrichment for Bird species - We have a diverse collection of birds at Colchester Zoo which vary greatly in physical adaptations and levels of intelligence. We use environmental enrichment to stimulate them in different ways. Presentation of food plays an important part in the enrichment we do. We also use toys and natural materials wherever possible. Obviously different things are effective for different species and individuals but we’d like to give you an idea of some of the things used.
  
  Scatter feeds are used a lot to prolong feeding and encourage the birds to forage. Main food items can be used and small things like seeds and insects work well, such as with our keas and ibis. Different sized and whole fruit is given to our parrots who manipulate it with their feet and beaks. A variety of nuts are given to the macaws which again provide stimulation as well as nutrition. We hang or spear fruit on branches for some birds and also hide food in boxes and paper for birds like our lories, magpies and hornbills. We make food ice pops in summer. Our lory nectar is rarely given in a bowl, instead we hang paper cups and bottles around the enclosure. We hang small animal drinker bottles which they have learnt to use. Our keas have a barrel which has holes in, which we put food in. They must physically push and pull the barrel around to obtain the food. We use this and other methods of enrichment randomly to keep the birds interested.
  
  Boxes and bottles make good toys on their own for many, or stuffed with straw for hornbills, cranes and keas. These birds also like unusual objects to play with such as metal lids and balls. Straw, bark and branch piles stimulate foraging among many, especially our ibis and cranes. We need to provide natural materials for the parrots to chew and use natural branches in most bird enclosures. We want the enclosures themselves to be as enriching as possible and allow natural behaviour.

• Enrichment for Prosimians - The prosimians are a group of primate that includes the lemurs.
  At Colchester Zoo we currently have Red ruffed lemurs, Black and white ruffed lemurs and Ringtailed lemurs.
  Prosimians can be very hard to enrich as they do not have opposable fingers, this means that they find it harder than the monkeys and the apes to manipulate items. The Ringtailed lemurs can also be very wary of new objects in their enclosure and therefore harder still to provide enrichment for. Even so there are many methods that we can utilise to keep the lemurs stimulated.
  Most of the lemurs' enrichment revolves around their diet, hiding it within boxes and bags works well as does hanging whole food from the perching. Sometimes the food will be cut up extremely small and thrown amongst the grass encouraging them to forage naturally. All these methods aim to prolong their feeding times.
  Sensory enrichment is another form of enrichment that we have had some success with. As they rely on scent as their main form of communication amongst each other, we can occasionally remove an item of perching from one lemur exhibit and place it in another.
  As most primates, the lemurs are a social animal and live in family units the size depending on the species. With 8 ringtailed lemurs, you will be able to see them engaging in many social activities from feeding together, grooming, playing, scent marking and participating in stink fights, the aim of which is to attract the attention of the dominant female.
  

• Enrichment for Sealions - When people think about animal training they often think of sealions balancing balls on their noses or jumping through hoops. Training animals of all kinds is a good way of enriching their lives. Animals in captivity don’t have predators nor do they have to worry about food or migration etc. So they need something to keep them mentally and physically stimulated. We can do this through training sessions even if what we train isn’t something that animal would naturally do. Training can also be helpful for different medical procedures. You can use training to teach animals to live in the environment you provide for them.
  
  We have trained all the sealions to target a different shape so when separating them we can move the shapes around and get the sealions to target their own shape.
  
  We are training each sealion to lie down with their front flippers tucked in and their back flippers extended out behind. This is so we can take a blood sample from the back flippers without having to restrain or sedate the sealions. To date we have never taken blood but it is useful to train for the future and we practice it every day.
  
  Each sealion is trained to open their mouth, so we can have a good look inside and check teeth. The sealions will also let us check their ears and eyes.
  
  For our feed times we have taught the sealions to touch a target on the windows around the pool. This gives people an excellent opportunity to see the sealions close up and the sealions a chance to see lots of different people. Two of our sealions can also touch a target held on our under water viewing tunnel.
  
  For our feeds we have taught the sealions to impersonate seals by sliding on their belly. We have taught this so we can tell people and demonstrate the differences between seals and sealions.
  

• Enrichment for Display Birds - On the bird display section we are responsible for the care of a variety of different types of bird ranging from tiny parakeets to enormous vultures and every different shape, size and colour in between. As an integral part of their care, we recognise that the use of ‘enrichment’ has huge benefits to play in maintaining the health and general well being of our charges.
  Of course, we do use ‘traditional’ methods of enrichment with our birds and if you were to take a look into the parrot aviaries, you could not but help notice the plastic balls, cardboard boxes, string, rope, paper bags, puzzles, leather dangly bits, fresh browse and an array of other toys and oddments put there for their pleasure.
  When it comes to birds of prey however, the task of providing ‘traditional’ enrichment becomes more challenging. On the whole they do not share the same inquisitive minds as the parrot species, so more often than not the addition of a toy to an enclosure would be largely ignored and at worst could even frighten the bird. That doesn’t mean that we give up on the idea altogether though. For example, we have found that placing food in cardboard boxes or tubes for vultures means they have to work for their lunch in much the same way as they have to open up a carcass in the wild. Turkey vultures, one of the few birds of prey with any kind of a sense of smell to talk about, will spend time sniffing out treats hidden around their enclosure. Changing perching around alters a bird’s environment and feeding whole carcass food is a real hit as the birds will spend much of an afternoon plucking at fur or feathers, teasing out bones and pulling on ligaments.
  
  But when talking about enrichment, then it is an absolute must that we also talk about training. Training is enrichment! Of course training does allow us to perform public demonstrations that are both entertaining and educational (we hope), but it also has huge benefits for the birds.
  
  Firstly, training stimulates the birds mentally. It makes them think. They have to work out what we are asking of them. In the same way as doing a crossword puzzle or playing a game of chess is enriching for us, then learning a behaviour is enriching for a bird. Also, training can be physically demanding. You can ask a bird to fly, climb or run and this improves the health of the bird and in turn it’s general well being.
  
  Secondly, training is a means to enrichment. A trained bird can be allowed to perform natural behaviours that are impossible within the confines of an aviary. A buzzard can soar on the thermals. Harris’ hawks can cooperate in a team to hunt down a pretend rabbit. Parakeets can explore in a flock. A kite can snatch food in mid air as it would insects in the wild and a falcon can escape the blistering heat of a hot summer’s day and rise carefree up into the clouds to cool off. All this is possible because the birds are trained.
  
  So, whilst ‘traditional’ enrichment may not always be that obviously in effect at the Bird Displays section, don’t worry, the birds are leading full and enriched lives.