In a new series of features, the Earth Times asks two leading experts to give their views on some of the hottest green topics of the 21st century. This week, we ask: Are zoos a force for good, or just an out-dated mode of animal cruelty? Tackling the issue head-on are Liz Tyson and Rosalind Smith.

Liz Tyson is the director of the Captive Animals' Protection Society, a UK-based charity leading the campaign to end the use of animals in entertainment. Working for a 'world without cages', CAPS encourages a more compassionate attitude and relationship between humans and animals and seeks to end the exploitation of animals in circuses, zoos and the exotic pet trade.

Rosalind Smith is a marketing assistant at Newquay Zoo Environmental Park in Cornwall, England. The award-winning zoo is home to more than 130 species of animal, including lion and zebra. The zoo is an active member of the Vietnamese Carnivore and Pangolin conservation programme, and supports a number of other global conservation initiatives, among them projects working to protect red-fronted macaws in Bolivia and sloth in Colombia.

With the internet, as well as DVDs, 3D TV etc, are zoos really necessary to teach people about animals in the 21st century?

Rosalind: I would say definitely. The overall trend from research done on the success on TV and DVD conservation messages is that the viewing public are becoming hardened to them. A visit to the Zoo is interactive - visitors see the animals, and then are able to learn more about them and then realise - "that fishing cat we saw is the most endangered cat in the world" and there is the link between the animal you have seen, their care and their IUCN status.

Liz: No, not at all. There is a wealth of information out there for someone who is interested in learning about wildlife to access at the touch of a button. Furthermore, the educative message delivered by zoos is, at best, distorted and, at worst, damaging to the cause that the zoos purport to champion - that is; the conservation of species.

A zoo shows the animal completely out of context, outside of its natural habitat and the ecosystem it was designed to inhabit. Also, the message that the child takes away with them is: if you ever you want to see a tiger, come to the zoo, where we can show you one at your convenience. What it fails to demonstrate to the child the urgency of the need for habitat conservation, or the complexity of the role of the tiger in its natural habitat, or the ways in which that child could aid the conservation of the species in reality.

What are the differences between 'good zoos' and 'bad zoos'?

Rosalind: This is such a huge question. A good zoo is one that has the animal welfare at the top priority, which makes an effort to recreate the natural environment that these species thrive in. A good zoo supports a number of conservation projects - "puts it money where its mouth is" so to speak, and promotes conservation projects round the world alongside donating skills, time and money. A good zoo will put a strong emphasis on education and run workshops, educational talks and make educational materials in order that conservation is accessible to all ages.

But how does a zoo manage to do all of these things unless it has visitors? So from my point of view a good zoo will also provide an amazing visitor experience, with feeding talks, a chance to feed the animals yourself, open exhibits and a chance to get closer to the animals and species. A good events diary and value for money will also go a long way to making a zoo a good zoo for visitors.

Liz: Whilst we are fundamentally against the keeping of animals in captivity for entertainment, it would be wrong to deny that some zoos are worse than others. Just last year, we carried out an investigation where the owner of a zoo sliced a growth off the face of one of the animals in its petting zoo with a penknife without any anaesthetic rather than take it to the vets. Another zoo we investigated feeds the animals stale bread and cakes as the majority of their daily diet.

Every single investigation our organisation has carried out into zoos has led to the exposure of serious issues; for the animals, the staff or the visitors. These zoos range from some of the country's biggest and longest-established to small set-ups where amateur animal collectors have turned their menageries into money-making ventures. As such, what may appear to be a "good zoo" on the surface, may prove to be something very different when you begin to dig deeper. Animals are not ours to control and imprison and as such, I agree that there are "bad zoos", I agree that there are "worse zoos" but I do not believe that there is such thing as a "good zoo".

Can artificial enclosures ever be a proper substitute for an animal's natural habitat?

Rosalind: In reality - no, not really - but a good zoo will aim to recreate a natural habitat as far as possible. For example our Capuchin monkey enclosure has been recently redesigned so it includes lots more foliage, leaves, bark - to recreate a jungle habitat as opposed to it looking like an army assault course with planks and ropes as some do.

Liz: Having had the privilege of seeing troops of monkeys springing from tree to tree in complete freedom, having come across the paw print of a jaguar who had recently passed over the trail our group was walking, having seen a deadly snake devour a frog whole, having seen the enigmatic pink river dolphins rise up out of the river for air and having seen macaws flying high above the trees screeching at interlopers in defence of their territory, I can say with great confidence that a zoo enclosure can never be a proper substitute for an animal's natural habitat.

A number of strict standards are currently in place for zoos to adhere to. But what further improvements can still be made?

Rosalind: Zoos in this country are justifiably bound by regulations regarding the treatment of animals etc. Zoo's abroad do not necessarily have the same guidelines that we do and this something that should be focused on. In the UK zoos all have to meet a very high standard.

Liz: There are over 400 zoos in the UK alone, ranging from butterfly farms to menageries of 100 or so animals to the immense safari parks that have thousands of animals ranging across large areas of land. Many of the smaller zoos are exempt from the licensing standards and thus, are not subject to inspections. For the larger zoos, they are inspected once a year (at best) or once every three years (as a minimum). The inspection is carried out over a maximum of two working days and might have to assess hundreds or even thousands of animals. When you bear in mind that the inspectors also need to review record keeping, health and safety, procedures, education and conservation contribution in the allotted time, it becomes clear that, even with the best of intentions, the system is simply unworkable.

Do zoo visits really inspire a passion for conservation, or are they merely passive entertainment?

Rosalind: I think this depends very much on who the visitor is. There are some people who visit zoos, see the animals but don't engage with the other information and messages available. However a visitor who is interested in the animals and in conservation efforts can be really inspired by a visit to the zoo to get involved and to do more to help, whether this be donating time, money or skills to a cause, or making simple changes at home, such as switching all the lights off, to aid the fight against global warming. So definitely zoos can inspire a passion for conservation.

It's also important to note that whilst yes, zoos have had a history in the past of not doing as much as they should for the animals in their care, zoos are no longer about animals in cages. Zoos definitely have a place in the world whilst human activity is destroying habitat and the environment at the rate that it is. Otherwise a lot of our most important and loved species of animals, birds and plants will no longer be around for future generations.

Liz: It is impossible to say what zoos inspire in other people - I am sure that for some people they do inspire passion in the same way they provoke sadness or anger in others. I think the overriding point here is that, even if they did inspire a passion for conservation, the end does not justify the means. Subjecting an animal to a lifetime of captivity, whether to inspire a passion for conservation or to entertain are two sides of the same coin. One motivation may be seen as more acceptable from a societal point of view but the situation of the tiger pacing up and down in his enclosure day-in day-out remains the same regardless of the motivation of the zoo owners.

For more information, check out:

Captive Animals' Protection Society and Newquay Zoo Environmental Park