This is an interesting post. In a thread about innovation, it'd be impossible to not mention technology, as that has obviously played a huge role in the development of the modern world, including zoos, but I like how the post didn't give a blanket positive outlook on technology, as there are certainly both zoos that have used technology to enhance their animal exhibits, but also zoos in which technology has been a hindrance to exhibit quality.3. Interactive screen, Nordsøen Oceanarium
Electronic displays in zoos
Photo: @snowleopard
Electronic displays, computer generated images, interactive screens and related technology, for which I invented a collective name virtualia, have found its way to zoos. Often, the effect is not good. The strength of zoos is that, with a big cost and effort, they showcase real, living animals. Fitting entertainment attractions with virtual creations runs into a danger summed by Cory Doctorow in the scifi story Down and Out in the Magic Kingdom. People can watch virtual images at home and don't need to go out for them. One can put all the virtual material online and close the place.
This example in Nordsøen Oceanarium shows how to do electronic displays and CGI well. I analyzed it, and managed to describe six principles of well done virtualia:
- IT should show something meaningful, not just be for its own sake.
- Use artificial only to show things which cannot be shown real. An example would be animals impossible to keep in zoos like giant whales. Don't replace real with artificial.
- Virtualia should not distract visitors from real-life displays, because these are the strength of the zoo.
- Clearly separate real and artificial in space. Don't try mixing displays and real nature. This never really works and can produce an uncanny feeling.
- Blinking lights or noise should not disturb those visitors who want to relax in peace. Many people have an excess of computers screens at work and wish to escape from them.
- Understand that IT is short-lived. Today cutting-edge animation will look painfully old 10 years in the future.
Similar examples:
Too many to mention. Unfortunately, some electronic displays are not well done. For example, many Zoochat members complained on electronic information plates in aquaria which slowly switch between species, making identifying fish in tanks frustrating. Others break down altogether.
Photo: @Chlidonias
This display appears to capitalize on, and probably promote, internet addiction and similar behaviors. These manifest in that people compulsively look for an electronic display or play computer games, and are now recognized as a serious danger to mental health. They affect a significant percentage of people, especially young. Therefore, zoos and aquaria should be careful with virtual displays!
Zoo of the Future: A Photographic Gallery of Innovation in Zoological Gardens of the World
- Thread starter Jurek7
- Start date
10. Cheetah and rhino mixed exhibits
Mixed-species exhibits with carnivores 1.
Photos: @devilfish
Mixed species exhibits became very common in zoos, to save space and to provide more interest to visitors. However, mixed species exhibit involving cats, and exhibits of carnivores and potential prey animals are rare. Several mixed exhibits of Cheetah and rhinos have been successful: Borås Djurpark, Attica Zoological Park, Flamingo Land (White Rhinos) and Zoo Leipzig (Black Rhinos).
Photo: @snowleopard
The exhibit at Boras is divided by a line of rocks, through which only cheetah can pass. Leipzig zoo designed a whole system of rock crevices and hiding places for cheetah, including a large raised grassy area.
Similar exhibits:
Photos: @devilfish
Zoorasia zoo mixes a single Cheetah, Eland, Grant's Zebras and Reticulated Giraffes. Apparently, it is the cheetah which is chased more often. Apparently, no animal was injured, but stressful interactions are common.
Photo: @Javan Rhino
However, this exhibit may be an inspiration to another, fully successful one. For example, maybe a giraffe enclosure with cheetah would work, without other ungulates? Or maybe African ungulates could be successfully mixed with servals, or other smaller carnivores, for example caracals, jackals, bat-eared foxes or zebra mongoose?
Other big cats have practically never been successfully mixed with other species, unless they were tame animals raised together. In that case, a lion will happily lay with a lamb. All I recall are small fish in moats of tigers and jaguars, and a Chinese softshell turtle which lived for some time in the the tiger moat in Frankfurt Zoo. Note, however, that there is another precedent. Wild mongoose moved in and life in dry moats of lions and tigers in one Asian zoo.
Mixed-species exhibits with carnivores 1.
Photos: @devilfish
Mixed species exhibits became very common in zoos, to save space and to provide more interest to visitors. However, mixed species exhibit involving cats, and exhibits of carnivores and potential prey animals are rare. Several mixed exhibits of Cheetah and rhinos have been successful: Borås Djurpark, Attica Zoological Park, Flamingo Land (White Rhinos) and Zoo Leipzig (Black Rhinos).
Photo: @snowleopard
The exhibit at Boras is divided by a line of rocks, through which only cheetah can pass. Leipzig zoo designed a whole system of rock crevices and hiding places for cheetah, including a large raised grassy area.
Similar exhibits:
Photos: @devilfish
Zoorasia zoo mixes a single Cheetah, Eland, Grant's Zebras and Reticulated Giraffes. Apparently, it is the cheetah which is chased more often. Apparently, no animal was injured, but stressful interactions are common.
Photo: @Javan Rhino
However, this exhibit may be an inspiration to another, fully successful one. For example, maybe a giraffe enclosure with cheetah would work, without other ungulates? Or maybe African ungulates could be successfully mixed with servals, or other smaller carnivores, for example caracals, jackals, bat-eared foxes or zebra mongoose?
Other big cats have practically never been successfully mixed with other species, unless they were tame animals raised together. In that case, a lion will happily lay with a lamb. All I recall are small fish in moats of tigers and jaguars, and a Chinese softshell turtle which lived for some time in the the tiger moat in Frankfurt Zoo. Note, however, that there is another precedent. Wild mongoose moved in and life in dry moats of lions and tigers in one Asian zoo.
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The difficulty with something like mongoose and bat-eared fox would primarily be that they are prolific diggers, and the holes they create could pose a risk of injury to the ungulates. It's the same reason it's relatively rare to see warthogs in mixed-species set-ups with other ungulates.
10. Cheetah and rhino mixed exhibits
Mixed-species exhibits with carnivores 1.
Photos: @devilfish
Mixed species exhibits became very common in zoos, to save space and to provide more interest to visitors. However, mixed species exhibit involving cats, and exhibits of carnivores and potential prey animals are rare. Several mixed exhibits of Cheetah and rhinos have been successful: Borås Djurpark, Attica Zoological Park, Flamingo Land (White Rhinos) and Zoo Leipzig (Black Rhinos).
Photo: @snowleopard
The exhibit at Boras is divided by a line of rocks, through which only cheetah can pass. Leipzig zoo designed a whole system of rock crevices and hiding places for cheetah, including a large raised grassy area.
Similar exhibits:
Photos: @devilfish
Zoorasia zoo mixes a single Cheetah, Eland, Grant's Zebras and Reticulated Giraffes. Apparently, it is the cheetah which is chased more often. Apparently, no animal was injured, but stressful interactions are common.
Photo: @Javan Rhino
However, this exhibit may be an inspiration to another, fully successful one. For example, maybe a giraffe enclosure with cheetah would work, without other ungulates? Or maybe African ungulates could be successfully mixed with servals, or other smaller carnivores, for example caracals, jackals, bat-eared foxes or zebra mongoose?
Other big cats have practically never been successfully mixed with other species, unless they were tame animals raised together. In that case, a lion will happily lay with a lamb. All I recall are small fish in moats of tigers and jaguars, and a Chinese softshell turtle which lived for some time in the the tiger moat in Frankfurt Zoo. Note, however, that there is another precedent. Wild mongoose moved in and life in dry moats of lions and tigers in one Asian zoo.
This is a style of mix though, that while it's been done "successfully", I'd really like to see some zoos with this mix do some more research on stress hormones and behavior in these mixed-species exhibits. In order for a mixed-species exhibit to be successful, in my opinion, it should not only include species that won't cause direct, noticeable harm (e.g., predation, disease risk, injuries), but should also consider and evaluate more subtle harm, such as behavioral differences/abnormalities, and stress levels. While I have no doubt these exhibits are great for visitors, I wonder how good they really are for the cheetahs and ungulates.
Generally, when changing, it is often not possible to know the borders unless one crosses them. So I describe some mixed successes and failures, because they have an important role in improving zoos.
You mentioned a need of evaluating exhibits for stress of animals. Surprisingly, real feelings of animal often play little role in treating exhibits.
Warsaw zoo has a brown bear exhibit in a public park near the entrance to the zoo. There were several studies that these bears breed, behave naturally and have the same level of stress hormones as brown bears in another exhibit inside the zoo. Still there were many calls to close this exhibit because it is 'principally' bad. There were many studies of dolphins and killer whales showing they live, have stress hormones and all possible characteristics no worse than wild animals, but activists still want to close the dolphinaria and repeat they think the cetaceans suffer.
11. Arctic tundra, Zoo Sauvage of St-Félicien, and others
Mixed-species exhibits with carnivores 2.
Following up on the carnivore mixed species exhibit thread, I selected several unusual exhibits.
Photo: @TinoPup
In the wild, Arctic foxes follow polar bears for weeks at a time. However, this mix, which has existed since 2000, is unusual for a zoo to the point that some Zoochatters considered it impossible. The success of these exhibits seems to come from their size (ca 2,670m2 / 28,800 ft2 and 2,800 m2 / 30,500 ft2 from Google Earth) and hilly shape so the foxes can easily remain out of sight of the bear. Foxes seem to have an innate drive to walk for long periods and benefit from such a large exhibit probably more than the much bigger bears.
Photo: @zoo_enthusiast
I did not find a photo of Arctic foxes from this zoo, so this one is a stand-in by @Maguari
Dhole and sun bear mixed exhibit at ZooParc de Trégomeur
Photo: @Maxime
I like this exhibit because it chose threatened species, ones relatively rare in zoos, and not usually mixed. Dholes used to have a bad reputation because, despite weighing less than a golden retreiver, dholes in large packs regularly hunt sambar deer the size of a light horse, and were even observed to chase away and kill tigers. Here, three dholes and three sun bears coexist without a problem. The canids also have access to their own exhibit.
Photo: @Maxime
Biologists describing confrontations between lions and spotted hyenas in East Africa found that the group which cumulatively has a bigger body mass dominates the other. So part of the success may be that this is a relatively small group of dholes.
A stand-in dhole by: @Austin the Sengi
Crab-eating raccoon and bush dogs Zoo Parc Overloon
Photo: @vogelcommando
Photo: @snowleopard
Another two species uncommon in zoos and rarely mixed. Bush dogs, although small, are serious predators, cooperatively hunting prey as big as capybara, rhea, brocket deer, and tapirs. So somebody may better watch out for its ringed tail!
Photo: @Morgan
Mixed species exhibit, Parque de Las Leyendas
Photo: @Nick@Amsterdam
In this island exhibit for tayras, tufted capuchins, and South American coatis, apparently, at least coatis and capuchins breed. Note that tayras eat lots of fruit in the wild, and their biggest recorded prey is an opossum. In fact, capuchins may turn out to be the most troublesome in this mix.
Photo: Giant Eland
A stand in tayra by @ThylacineAlive
Chitwan, Zoo Ostrava
Photo: @twilighter
Asian black bears and hanuman langurs in a 1,4 ha enclosed patch of forest win praise in many points: uncommon species, unusual mix, rarely displayed habitat and a giant, spacious exhibit with natural vegetation. This exhibit has been described several times on Zoochat, and has its own page on Zoolex: ZooLex Exhibit - Chitwan
Photo: @twilighter
Crocodile and dwarf mongoose mixed exhibit, Basel Zoo
Photo: @twilighter
Members of the order Carnivora are not always the top dogs. This exhibit is entirely indoors. It started as crocodile and fish exhibit, and over the years, birds and dwarf mongoose were added. Mongoose bred several times and move between the branches at the back of the exhibit, although crocodiles apparently snatched several ones passing close. This concept was copied by Aquatis Lausanne, where mongoose have a long extension of the land area.
Photo: @lintworm
Stand in photo @Green_mamba
Unfortunately I did not find a photo of another small mixed exhibit which existed in Basel zoo in the 2000s -2010s. This is a shame, because it was one of most unusual concepts in any zoo. How can snakes and mice coexist in one average-sized exhibit?
The trick was surprisingly simple. Two adult puff adders are huge, ground living, nocturnal and generally slow. Harvest mice are climbers, diurnal and agile. The adders stayed in the front, sandy part. The back part was full of dense sticks, which snakes could poorly enter. Especially, thick straw formed a sort of palisade. A group of harvest mice lived on tall weeds sticking out behind and high above snakes. They also had their own resting place accessible through an opening in the wall. This exhibit existed for years, but few years ago was replaced by an exhibit of horned adders and Nephila spiders. Nice still, but not so unique.
Mixed-species exhibits with carnivores 2.
Following up on the carnivore mixed species exhibit thread, I selected several unusual exhibits.
Photo: @TinoPup
In the wild, Arctic foxes follow polar bears for weeks at a time. However, this mix, which has existed since 2000, is unusual for a zoo to the point that some Zoochatters considered it impossible. The success of these exhibits seems to come from their size (ca 2,670m2 / 28,800 ft2 and 2,800 m2 / 30,500 ft2 from Google Earth) and hilly shape so the foxes can easily remain out of sight of the bear. Foxes seem to have an innate drive to walk for long periods and benefit from such a large exhibit probably more than the much bigger bears.
Photo: @zoo_enthusiast
I did not find a photo of Arctic foxes from this zoo, so this one is a stand-in by @Maguari
Dhole and sun bear mixed exhibit at ZooParc de Trégomeur
Photo: @Maxime
I like this exhibit because it chose threatened species, ones relatively rare in zoos, and not usually mixed. Dholes used to have a bad reputation because, despite weighing less than a golden retreiver, dholes in large packs regularly hunt sambar deer the size of a light horse, and were even observed to chase away and kill tigers. Here, three dholes and three sun bears coexist without a problem. The canids also have access to their own exhibit.
Photo: @Maxime
Biologists describing confrontations between lions and spotted hyenas in East Africa found that the group which cumulatively has a bigger body mass dominates the other. So part of the success may be that this is a relatively small group of dholes.
A stand-in dhole by: @Austin the Sengi
Crab-eating raccoon and bush dogs Zoo Parc Overloon
Photo: @vogelcommando
Photo: @snowleopard
Another two species uncommon in zoos and rarely mixed. Bush dogs, although small, are serious predators, cooperatively hunting prey as big as capybara, rhea, brocket deer, and tapirs. So somebody may better watch out for its ringed tail!
Photo: @Morgan
Mixed species exhibit, Parque de Las Leyendas
Photo: @Nick@Amsterdam
In this island exhibit for tayras, tufted capuchins, and South American coatis, apparently, at least coatis and capuchins breed. Note that tayras eat lots of fruit in the wild, and their biggest recorded prey is an opossum. In fact, capuchins may turn out to be the most troublesome in this mix.
Photo: Giant Eland
A stand in tayra by @ThylacineAlive
Chitwan, Zoo Ostrava
Photo: @twilighter
Asian black bears and hanuman langurs in a 1,4 ha enclosed patch of forest win praise in many points: uncommon species, unusual mix, rarely displayed habitat and a giant, spacious exhibit with natural vegetation. This exhibit has been described several times on Zoochat, and has its own page on Zoolex: ZooLex Exhibit - Chitwan
Photo: @twilighter
Crocodile and dwarf mongoose mixed exhibit, Basel Zoo
Photo: @twilighter
Members of the order Carnivora are not always the top dogs. This exhibit is entirely indoors. It started as crocodile and fish exhibit, and over the years, birds and dwarf mongoose were added. Mongoose bred several times and move between the branches at the back of the exhibit, although crocodiles apparently snatched several ones passing close. This concept was copied by Aquatis Lausanne, where mongoose have a long extension of the land area.
Photo: @lintworm
Stand in photo @Green_mamba
Unfortunately I did not find a photo of another small mixed exhibit which existed in Basel zoo in the 2000s -2010s. This is a shame, because it was one of most unusual concepts in any zoo. How can snakes and mice coexist in one average-sized exhibit?
The trick was surprisingly simple. Two adult puff adders are huge, ground living, nocturnal and generally slow. Harvest mice are climbers, diurnal and agile. The adders stayed in the front, sandy part. The back part was full of dense sticks, which snakes could poorly enter. Especially, thick straw formed a sort of palisade. A group of harvest mice lived on tall weeds sticking out behind and high above snakes. They also had their own resting place accessible through an opening in the wall. This exhibit existed for years, but few years ago was replaced by an exhibit of horned adders and Nephila spiders. Nice still, but not so unique.
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You could easily cherry-pick studies showing no behavioral or physiological differences based on zoo exhibit factors, however someone else could easily cherry-pick studies showing behavioral or physiological differences. However, it is impossible to know how a factor is influencing an individual animal without assessing or evaluating their individual behavior and physiology. In cases where there are multi-layered, complex mixed-species exhibits, I would certainly hope any reputable zoo repeatedly evaluates the behavior and stress of individual animals, in order to ensure it is truly working for all residents. I don't know much about the Warsaw Zoo, but those studies you describe are great at determining if the Warsaw Zoo's exhibit is adequate for their current bears or not, but surely that study doesn't determine if every exhibit, at any zoo anywhere, is adequate for bears, and also doesn't determine if any individual bear would thrive in that exhibit. Animal welfare is complicated, and should really be based on actual data (which needs to be collected and analyzed), rather than based on emotions, gut feelings, anecdotal evidence, or over-generalizations. Again, I'm not saying any of these sorts of mixed exhibits are inadequate (many of them are likely fine), just that it is important to go through the scientific pathways in ensuring the exhibits are acceptable and there aren't unnoticed behavioral or physiological abnormalities.
12. The Nature Park Trails, Zoo Sauvage of Saint-Félicien
Mixed-species exhibits with carnivores 3.
Photo: @TheoV
Photo: @TinoPup
Zoo exhibits are generally too small to allow for predator-prey interactions except for very small animals. This zoo is an exception. The Nature Park Trails exhibit is a 325-hectare area visited by a tram ride over 7 km long and taking an hour. It has natural forest, prairie, ponds and replicas of farmsteads and camps. It shows American black bears, wapiti, white-tailed deer, bison, black-tailed prairie dogs, reindeer, muskox and mountain goat. Moose and some other animals my be separated*.
Photo: @TinoPup
According to Zoochatter reports, black bears receive their own food to keep them close to the train, but they still eat most of deer fawns. Nevertheless, the deer population maintains itself. Also, wild deer would likely naturally move into such a nice patch of habitat, like they settled on the grounds of several other zoos in North America.
Photo: @NRJMelvinT
*Thanks TinoPup for the update.
Similar exhibits:
Black bears were occasionally mixed with ungulates. I found information that Africam Safari in Puebla, Mexico mixed black bear, collared peccary, white-tailed deer, and waterfowl. However, I could not find a confirmation or any more detail about this exhibit. Several mixed exhibits exhist in Europe, but bears are not allowed to prey on other animals. Serengetipark Hodenhagen mixes black bears with kulan, bactrian camel, baboons, ostriches and Barbary sheep. Planète Sauvage, Ree Park - Ebeltoft Safari, and Safari de Peaugres mix black bears with bison. Animal Park Sante Croix mixes black bear, bison and coyotes.
Photo: @korhoen
Another idea which could inspire other exhibits. For example, mixing threatened gaur or banteng with sun bears or Asian black bears, yak with Asian black bear, or European brown bears with non-breeding European bison.
Mixed-species exhibits with carnivores 3.
Photo: @TheoV
Photo: @TinoPup
Zoo exhibits are generally too small to allow for predator-prey interactions except for very small animals. This zoo is an exception. The Nature Park Trails exhibit is a 325-hectare area visited by a tram ride over 7 km long and taking an hour. It has natural forest, prairie, ponds and replicas of farmsteads and camps. It shows American black bears, wapiti, white-tailed deer, bison, black-tailed prairie dogs, reindeer, muskox and mountain goat. Moose and some other animals my be separated*.
Photo: @TinoPup
According to Zoochatter reports, black bears receive their own food to keep them close to the train, but they still eat most of deer fawns. Nevertheless, the deer population maintains itself. Also, wild deer would likely naturally move into such a nice patch of habitat, like they settled on the grounds of several other zoos in North America.
Photo: @NRJMelvinT
*Thanks TinoPup for the update.
Similar exhibits:
Black bears were occasionally mixed with ungulates. I found information that Africam Safari in Puebla, Mexico mixed black bear, collared peccary, white-tailed deer, and waterfowl. However, I could not find a confirmation or any more detail about this exhibit. Several mixed exhibits exhist in Europe, but bears are not allowed to prey on other animals. Serengetipark Hodenhagen mixes black bears with kulan, bactrian camel, baboons, ostriches and Barbary sheep. Planète Sauvage, Ree Park - Ebeltoft Safari, and Safari de Peaugres mix black bears with bison. Animal Park Sante Croix mixes black bear, bison and coyotes.
Photo: @korhoen
Another idea which could inspire other exhibits. For example, mixing threatened gaur or banteng with sun bears or Asian black bears, yak with Asian black bear, or European brown bears with non-breeding European bison.
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12. The Nature Park Trails, Zoo Sauvage of Saint-Félicien
Mixed-species exhibits with carnivores 3.
Photo: @TheoV
Photo: @TinoPup
Zoo exhibits are generally too small to allow for predator-prey interactions except for very small animals. This zoo is an exception. The Nature Park Trails exhibit is a 325-hectare area visited by a tram ride over 7 km long and taking an hour. It has natural forest, prairie, ponds and replicas of farmsteads and camps. It mixes American black bears, moose, wapiti, white-tailed deer, bison, black-tailed prairie dogs, reindeer, muskox, mountain goat and bighorn sheep.
Photo: @TinoPup
According to Zoochatter reports, black bears receive their own food to keep them close to the train, but they still eat most of deer fawns. Nevertheless, the deer population maintains itself. Also, wild deer would likely naturally move into such a nice patch of habitat, like they settled on the grounds of several other zoos in North America.
Photo: @NRJMelvinT
Similar exhibits:
Black bears were occasionally mixed with ungulates. I found information that Africam Safari in Puebla, Mexico mixed black bear, collared peccary, white-tailed deer, and waterfowl. However, I could not find a confirmation or any more detail about this exhibit. Several mixed exhibits exhist in Europe, but bears are not allowed to prey on other animals. Serengetipark Hodenhagen mixes black bears with kulan, bactrian camel, baboons, ostriches and Barbary sheep. Planète Sauvage, Ree Park - Ebeltoft Safari, and Safari de Peaugres mix black bears with bison. Animal Park Sante Croix mixes black bear, bison and coyotes.
Photo: @korhoen
Another idea which could inspire other exhibits. For example, mixing threatened gaur or banteng with sun bears or Asian black bears, yak with Asian black bear, or European brown bears with non-breeding European bison.
The animals at Sauvage aren't that mixed. They no longer have bighorn sheep, and mountain goats are in their own exhibit in the walk-through area, not the tram area. The moose are fenced off in a paddock. The general area has hidden fences and things like that, so species are sectioned off, it's just not noticeable to the average visitor. I did see black bears near white-tailed deer and caribou, all with piles of kibble in front of them. I saw multiple fawns, as well.
How are the prairie dogs contained?
I don't think they are, other than they are in an absolutely massive field - close to as far as you can see in most directions. The only other species in that area were some domestics, mostly horses, in fenced paddocks along the tram road (one of the homestead set-ups). I didn't see signs of the prairie dogs in any other area.
Interesting! Quite the dangerous game they're playing there from an invasive species standpoint...
The fact this is possible concerns me from a welfare and ethics standpoint. One of the foundations of animal welfare are the freedoms from pain, injury, and discomfort. Clearly, housing captive animals in an exhibit that allows for the non-negligible chance of predation infringes on these freedom of the deer. Humanely euthanizing surplus births to feed to carnivores is one thing (not saying I agree with that, just that it isn't as ethically concerning), but encouraging or allowing active predation is much more concerning.
Not necessarily, I think. Groundhogs and chipmunks are the only ground squirrels that make it that far up in Quebec, so their survivability may not be as good as it is in, say, Marquette Co. WI
.
The very fact that they are able to maintain a colony of that size there says a lot though.Not necessarily, I think. Groundhogs and chipmunks are the only ground squirrels that make it that far up in Quebec, so their survivability may not be as good as it is in, say, Marquette Co. WI
How is it different from giving herps live prey such as crickets or mealworms?
They've been doing it for years and don't seem to have an issue. The animals stretched far, there has to be hundreds of them at least, but didn't get anywhere close to the outside area. It's possible they use some deterrent on the perimeter as well, like a powder or something like places normally use to keep rodents out. It's also possible they explain it on the tram ride, but the whole thing is in French
I would like to see the source for that statement as I find it hard to believe. The bears are very well fed and catching a fawn is a lot of work. I also saw several fawns with their mothers, in areas that I didn't see bears in.
Compare seeing a lizard hunt and eat a bug to a large mammal hunting down a deer. Being killed by a lizard is a relatively quick process, certainly more so than being hunted and killed by a bear, and as such the amount of pain experienced is likely much higher for the deer. It's also very fair to say that there are different calibers of acceptable welfare for different taxa- just look at what is considered acceptable for doing research on chimpanzees compared to what is acceptable for doing research on mice.
That depends, among others, on the local legislation. Where I live, feeding live mammals to one another would be illegal.