Given their invasiveness, it seems pretty darn irresponsible to me. Hopefully they'll be non-breeding animals.
Should zoos keep potentially invasive species?
- Thread starter Giant Panda
- Start date
Given their invasiveness, it seems pretty darn irresponsible to me. Hopefully they'll be non-breeding animals.
Ummm, what? You do realize they will be in a zoo enclosure with virtually no possibility of escaping and becoming an invasive species?
No enclosure is 100% escape-proof when human error is thrown into the mix and lots of non-native populations are descended from zoos. Raccoon dogs are proven invasives across eastern and northern Europe. They are adaptable generalists, highly mobile, and have a wide thermal tolerance range. As if the economic impact and threat to native wildlife weren't enough, they also pose a public health risk.
If the US had ratified the CBD, it would be obliged to take preemptive action against potential invasives. The EU, for instance, has the forward-thinking Commission Implementing Regulation 2016/1141 (which includes zoos). Regardless, as a conservation organisation, OKC Zoo should lead by example. Raccoon dogs are neither threatened nor, frankly, all that interesting to the bulk of visitors. However slim the likelihood, I don't think it's worth the risk.
I’m sure they will take plenty of precautions. Considering it’s a new exhibit, I’m sure there was plenty of planning. They made the decisions for some reason. There’s a reason there are TAGs. Zoos don’t just pick animals out of thin air to exhibit. If animals weren’t exhibited based on invasiveness, all zoos would have would be exotic megafauna and local species. US zoos probably couldn’t exhibit native European species and vise versa. Kinda defeats the purpose of exhibiting a wide variety of species for a greater education value if zoos are limited based on invasiveness.
Well, that's all right then!
Barring a recent change, raccoon dogs are not recommended by the AZA small carnivore TAG.
Actually, most species pose no real risk. However, going into an adaptable, mobile, generalist omnivore listed by DAISIE as one of the 100 worst invasives is just unnecessary. No zoo has enough species to justify that on collection grounds. There is also no evidence that displaying a vast range of species is educational for visitors.
To be taken seriously as conservation organisations, zoos cannot just be stamp collections. That is particularly true if those stamps pose a legitimate threat to local ecosystems.
Cool. So I guess we should be all on board for banning facilities in Florida from holding all non native crocodilians, pythons, or other tropical reptiles. While we’re at it, we should ban degus from being held in collections too because they are considered invasive in pretty much all the US and they are rodents so they are a huge escape risk. They have no conservation needs so why would a facility want them (hint: there are a few). Any aquariums by the coast can’t hold potentially invasive fish species either because the risk of a storm releasing them is too high as well.
You need to give more credit to the animal care professionals who make the decisions and the companies who build the exhibits. If you are so concerned about the local ecosystem around OK City, then why don’t you call them. I’m sure they’ll forgo the plan and construction that’s almost certainly nearly completed because one of the species they plan on housing (or potentially already house behind the scenes) is considered invasive and you don’t trust them to keep them secure. Maybe your example will prevent zoos from doing something so reckless in the future.
I don’t mean to be rude but that line of thinking doesn’t make sense to me.
Go on, what's so crucial about keeping raccoon dogs? You suggested, and swiftly dropped, a half-baked education argument; any other ideas? As suggested by my first post, I'd be quite happy if they were rescued and prevented from breeding. Context suggests that isn't the case, but we'll have to see. Your posts, however, suggest you'd support a breeding population. Why?
As for the attempts at absurd examples, I think they're quite the opposite. Wouldn't it be wonderful if the Everglades, say, were not a witless menagerie of non-native nasties? New Zealand, for example, has anti-reptile legislation similar to what you're satirising. If only Florida had enacted something similar (hint: they'd save millions of $$$ for starters).
I also recognise a continuum of invasiveness which, like most of my posts, you've chosen to ignore.
Now it's my turn to be confused. Are you honestly suggesting escapes never happen at accredited facilities? Again: introduce human error and no system is fool-proof.
Is this an attempt at goading? You realise the purpose of a discussion forum, right?
I don’t need to know the exact reasons as to why they want raccoon dogs or how they are obtaining them to trust that a large institution like Oklahoma City Zoo is getting these animals through a reputable source. I’ve never pretended to know why they are getting them or if they were a breeding pair. If it seemed like I did, it’s because I’m giving examples for why they might be getting them. I don’t feel like I need to fully explain why raccoon dogs have an educational benefit. Potentially these are rescues and they will have some sort of sign that tells people why they are not good pets and the harm they can cause the environment if they get out.
As for Florida, I wanted to give an example of how we trust those institutions to hold animals that we know are invasive and there is legislation on the legality of keeping those species. Would you be against a zoo in florida building a new reptile building because of the risk? What about the other examples I gave?
I do recognize the inherent risk of escape. It happens with every animal. But I think the immediate damage an escaped tiger could do is the same if not greater than the potential damage a pair of raccoon dogs could do. So why is it that the raccoon dog exhibit is too risky but you don’t have any issues with tigers or other dangerous animals being exhibited?
And I’m not goading. I just find your reasoning ridiculous so I was being sarcastic in the hopes to bring humor to a thread that has become way too serious.
I also feel like I’m addressing all of your points so to insinuate that you’re being ignored is absurd.
Maybe the immediate danger, a matter of days, is much bigger when a tiger escapes. Raccoon dogs are however an important vector of many diseases, most worryingly rabies. Their actual economic impact is actually not that bad, but their ability to spread lots of nasty diseases is a direct (human) health risk. Added to that is the fact that security of a tiger enclosure is a lot higher than that for your average small carnivore, so the actual risk of escape is higher for a raccoon dog than for a tiger.
I am not up to date with current legislation on invasives in Florida, but looking at the number they seem to have messed up big time... And in that regard zoos would do good in not being a potential source of more invasions, also from species not yet occuring wild in Florida, but for which there would be a risk. Zoos are branding themselves as environmental awareness centers, but building a facility with all kinds of potential invasives doesn't really help that message. Banning degu would be the same thing. Just look at the law the European Union has recently signed on banning several invasive plants and animals from being kept/sold. The list itself is far from perfect (and in some cases quite ridiculous), but the idea is sound. There have been enough modelling studies that have shown how cost effective such legislation is compared to cleaning up the mess after it's been created.
@Echobeast: To recap, my argument is that: 1) raccoon dogs are a potential invasive, 2) they present an escape risk, 3) there is no good reason to exhibit breeding animals. You've failed to refute any of the three, so scorning my stance as "absurd" and "ridiculous" rings pretty hollow.
So your last post suggests I should "trust" escapes won't happen, and you've followed that up by admitting they might. Cool.
The tiger point actually made me think. It's not equivalent to raccoon dogs, of course, because the trade-offs are different (for the RDs, no appreciable benefit weighed against the potential for a major conservation issue; for tigers, human safety against well-validated conservation, education, and economic benefits). Still a good question, though, and one some very senior figures are struggling with, given recent keeper deaths despite (or perhaps because of) the health and safety measures now in place. The answer: I don't know.
I agree with @lintworm on both Florida and degus. Again, there is a continuum of risk, so your aquarium example is too general for a meaningful response. A sturdy building on a temperate coastline holding only sensitive tropical reef species isn't a problem. An Open Pen Sea-Cage containing competitively superior non-native or GM species well-suited to that environment is an accident waiting to happen. In fact, it's one of the biggest issues facing marine conservation.
And anything in between? Obviously, it's a case-by-case issue. Since the case we're discussing is raccoon dogs, it's frustrating you're repeatedly ignoring them in favour of increasingly irrelevant alternatives.
For future reference, mockery and childish sarcasm rarely lighten the mood. And I wouldn't say this discussion was overly serious.
I didn't insinuate; I stated. You brought up the importance of TAGs, for instance, and ignored my prompt that raccoon dogs are not a recommended species. More systematically, you've repeatedly overlooked the specific threat raccoon dogs pose and instead retreated behind a string of what ifs. If you want to discuss this issue, discuss this issue. And if your insight ends with "I'm sure somebody somewhere knows what they're doing"... Message received.
So your last post suggests I should "trust" escapes won't happen, and you've followed that up by admitting they might. Cool.
The tiger point actually made me think. It's not equivalent to raccoon dogs, of course, because the trade-offs are different (for the RDs, no appreciable benefit weighed against the potential for a major conservation issue; for tigers, human safety against well-validated conservation, education, and economic benefits). Still a good question, though, and one some very senior figures are struggling with, given recent keeper deaths despite (or perhaps because of) the health and safety measures now in place. The answer: I don't know.
I agree with @lintworm on both Florida and degus. Again, there is a continuum of risk, so your aquarium example is too general for a meaningful response. A sturdy building on a temperate coastline holding only sensitive tropical reef species isn't a problem. An Open Pen Sea-Cage containing competitively superior non-native or GM species well-suited to that environment is an accident waiting to happen. In fact, it's one of the biggest issues facing marine conservation.
And anything in between? Obviously, it's a case-by-case issue. Since the case we're discussing is raccoon dogs, it's frustrating you're repeatedly ignoring them in favour of increasingly irrelevant alternatives.
For future reference, mockery and childish sarcasm rarely lighten the mood. And I wouldn't say this discussion was overly serious.
I didn't insinuate; I stated. You brought up the importance of TAGs, for instance, and ignored my prompt that raccoon dogs are not a recommended species. More systematically, you've repeatedly overlooked the specific threat raccoon dogs pose and instead retreated behind a string of what ifs. If you want to discuss this issue, discuss this issue. And if your insight ends with "I'm sure somebody somewhere knows what they're doing"... Message received.
Yes they should.
“Invasive” in a continental sense (outside of the very limited example of small carnivores in Australia) is a Bugbear/Boogyman argument. In my opinion only....
As I’ve posted before, I believe it is a, slightly more platable to a certain sect of Conservationist, argument to justify Humanity’s mastery over nature. I.e: all invasive species....all Livestock killers....all witches must be destroyed!!! ;-).
I think it’s an overblown argument....outside of small islands or otherwise isolated habitats at least. Damaging even in many cases to conservation.
The Raccoon Dog’s impact in North America as a destructive invasive species or a disease vector, were it to escape would be absurdly minimal. Outside of establishing a few isolated, semi-urban populations (and probably human dependent [the name Dog would make any program of eradication politically unteneble]) in the immediate vicinity of any escape...continent wide spread is unlikely.
In Oklahoma the Raccoon Dog would face stiff completion ecologically from Raccoons and Grey Foxes immediately. Opossums, Red Foxes, Badgers, Skunks, Feral Dogs and Cats (the persistence of the last two really sinks the “invasive” hysteria) less directly. Prededation by large Owls and Raptors, Coyotes, Cars, Sportsmen, and less heavily, Bobcats. Pity the learning curve they will face when confronting Rattlesnakes for the first time.
To sum up....they pose no real invasive threat and if they survive the small carnivore gauntlet that is North America....fine...nothing they bring is anything the Native Fauna isn’t already well equipped to deal with.
Putting them on the Channel Islands would be bad...but I have a hard time imagining a seriously negative impact anywhere else...and in their case, as with many “invasives”, would actually increase biodiversity! In the unlikely event they were able to establish themselves.
Like I said...”burn the witch” lunacy really to argue otherwise.
Especially regarding the likelihood of escape and establishment in the first place...
“Invasive” in a continental sense (outside of the very limited example of small carnivores in Australia) is a Bugbear/Boogyman argument. In my opinion only....
As I’ve posted before, I believe it is a, slightly more platable to a certain sect of Conservationist, argument to justify Humanity’s mastery over nature. I.e: all invasive species....all Livestock killers....all witches must be destroyed!!! ;-).
I think it’s an overblown argument....outside of small islands or otherwise isolated habitats at least. Damaging even in many cases to conservation.
The Raccoon Dog’s impact in North America as a destructive invasive species or a disease vector, were it to escape would be absurdly minimal. Outside of establishing a few isolated, semi-urban populations (and probably human dependent [the name Dog would make any program of eradication politically unteneble]) in the immediate vicinity of any escape...continent wide spread is unlikely.
In Oklahoma the Raccoon Dog would face stiff completion ecologically from Raccoons and Grey Foxes immediately. Opossums, Red Foxes, Badgers, Skunks, Feral Dogs and Cats (the persistence of the last two really sinks the “invasive” hysteria) less directly. Prededation by large Owls and Raptors, Coyotes, Cars, Sportsmen, and less heavily, Bobcats. Pity the learning curve they will face when confronting Rattlesnakes for the first time.
To sum up....they pose no real invasive threat and if they survive the small carnivore gauntlet that is North America....fine...nothing they bring is anything the Native Fauna isn’t already well equipped to deal with.
Putting them on the Channel Islands would be bad...but I have a hard time imagining a seriously negative impact anywhere else...and in their case, as with many “invasives”, would actually increase biodiversity! In the unlikely event they were able to establish themselves.
Like I said...”burn the witch” lunacy really to argue otherwise.
Especially regarding the likelihood of escape and establishment in the first place...
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And a very uninformed and demonstrably false opinion if you would know your invasives. It is true that the large majority of introduced species don't have any negative effects, but there are enough examples worldwide to be worried about also on large continents (though yes most of the famous and worst invasions have taken place on islands and Hawai'i is probably the invasion capital of the world...). But just as a few examples from all over the world and different taxa: Prosopis spp. invading drylands throughout the old world at tremendous speed and cost, marmorated stink bugs and Drosophila suzuki both threatening fruit growers with risks going into the 100's of millions, Ambrosia plants spreading with a high future probability of a lot of allergic reaction to its pollen, Australian acacia in most Mediterranean systems over the world and beavers causing havoc in Southern Chile.
Most species don't cause any problems, but the ones that do make up for that and it is way cheaper to prevent introductions happening in the first place than cleaning up the mess afterwards. There is a reason why countries like Chile, Australia and New Zealand are so strict on imports...
You are right. I should probably have stated specifically that my opinion is limited directly to mammals and most birds and a few reptiles.
I agree that many other species (fish, mollusks, insects, and plants) can be destructive even on a contenental scale. And that habitat destruction is contributing to the transition of continental habitats into something more insular.
Otherwise, I stand by my argument, false perhaps but most assuredly not uninformed.
Beavers in Chile is a pretty good example...the lack (aside from Pumas...which aren’t really) of an effective predator or any animal that utilizes the habitat in the same manner is key. However....North American beavers are almost as exclusively “destructive” in their native habitats. They may change the riverine habitats of Chile....but I think the landscape will adapt to their presence. The interchange that occurred with the merging of the continents continues. I’m kind of joking (reference my exception regarding isolated habitats in my original post) but the Beaver in Chile is an exception and not analogous to the Raccoon Dog in North America.
I agree that many other species (fish, mollusks, insects, and plants) can be destructive even on a contenental scale. And that habitat destruction is contributing to the transition of continental habitats into something more insular.
Otherwise, I stand by my argument, false perhaps but most assuredly not uninformed.
Beavers in Chile is a pretty good example...the lack (aside from Pumas...which aren’t really) of an effective predator or any animal that utilizes the habitat in the same manner is key. However....North American beavers are almost as exclusively “destructive” in their native habitats. They may change the riverine habitats of Chile....but I think the landscape will adapt to their presence. The interchange that occurred with the merging of the continents continues. I’m kind of joking (reference my exception regarding isolated habitats in my original post) but the Beaver in Chile is an exception and not analogous to the Raccoon Dog in North America.
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Zoos in the European Union are forced to phase out several species classed 'invasive'.
Unfortunately, the list of species is very bad. Several are popular zoo animals, good for education, which are already well established and commonly naturalized in Europe (like raccoon and Egyptian goose) or which invasive potential is zero (coati and American bison). At the same time the list does not include e.g. American mink which is very invasive, and animals fresh escaping from fur farms massively damage bird populations. Really details ruined a potentially very useful regulation.
Coming to think, zoos in the European Union should really lobby to be excluded from regulations like import of animal products and keeping invasive species. Zoo regulations already force zoos to do more than prevent uncontrolled spreading invasive species or animal diseases.
Unfortunately, the list of species is very bad. Several are popular zoo animals, good for education, which are already well established and commonly naturalized in Europe (like raccoon and Egyptian goose) or which invasive potential is zero (coati and American bison). At the same time the list does not include e.g. American mink which is very invasive, and animals fresh escaping from fur farms massively damage bird populations. Really details ruined a potentially very useful regulation.
Coming to think, zoos in the European Union should really lobby to be excluded from regulations like import of animal products and keeping invasive species. Zoo regulations already force zoos to do more than prevent uncontrolled spreading invasive species or animal diseases.
I believe this is an important discussion. It is well known that invasive species (both plant and animal) are one of the chief threats to nature. Plants and insects are the worse (I think) because of the near impossibility of eradicating them. Florida, as most of us know, is a disaster.
My question is, how many invasive species are the result of zoo escapes? I am not being sarcastic, this is a legitimate question. I would love to hear some specific examples, because off the top of my head I don't know of any. I believe the Burmese pythons and green iguanas in Florida are from released pets. The nutria throughout the Gulf Coast are from a fur farm whose fences were knocked out by a hurricane. The ungulates (nilgai et al) in south Texas are from game ranches, but not traditional zoos I don't think.
Examples from around the world are fine, but remember this discussion started with a zoo in the United States (and an AZA accredited zoo at that). I find it hard to believe (actually I find it impossible to believe) that an accredited zoo cannot keep track of two medium sized carnivores.
My question is, how many invasive species are the result of zoo escapes? I am not being sarcastic, this is a legitimate question. I would love to hear some specific examples, because off the top of my head I don't know of any. I believe the Burmese pythons and green iguanas in Florida are from released pets. The nutria throughout the Gulf Coast are from a fur farm whose fences were knocked out by a hurricane. The ungulates (nilgai et al) in south Texas are from game ranches, but not traditional zoos I don't think.
Examples from around the world are fine, but remember this discussion started with a zoo in the United States (and an AZA accredited zoo at that). I find it hard to believe (actually I find it impossible to believe) that an accredited zoo cannot keep track of two medium sized carnivores.
Well, David Gill was responsible for introducing sacred ibis to the British Isles, but I don’t think that one comes as a surprise to anybody...
Lex Salisbury was also responsible for the escape of patas monkeys in Florida from his private zoo; this too should not surprise anyone who is familiar with him.
Beyond that, I don’t know any specific examples. I know that invasive animals have escaped from zoos in Europe, but I’m not familiar with that occurring here in North America. Perhaps some tropical birds have escaped and bred after avaries collapsed during hurricanes?
Lex Salisbury was also responsible for the escape of patas monkeys in Florida from his private zoo; this too should not surprise anyone who is familiar with him.
Beyond that, I don’t know any specific examples. I know that invasive animals have escaped from zoos in Europe, but I’m not familiar with that occurring here in North America. Perhaps some tropical birds have escaped and bred after avaries collapsed during hurricanes?
I cant think of any invasive species that originated as escapees from AZA zoos, but it is certainly not outside the realm of possibility. Even medium sized carnivores can escape from AZA zoos and remain missing for a long time, like Sunny the red panda from the Virginia Zoo In a Rare Zoo Escape, Sunny the Red Panda Is Still at Large.
If we widen the consideration to introduced, but not necessarily invasive species, that originated from zoos then that has happened before. The black eastern grey squirrels found throughout the city of Calgary are descendants of escapees from the Calgary Zoo and pets from the 1930's. When I visited the Jurong Bird Park in Singapore I saw free-ranging green iguanas, although I don't know if the population there is breeding and whether it originated from the Jurong Bird Park or elsewhere.
If we widen the consideration to introduced, but not necessarily invasive species, that originated from zoos then that has happened before. The black eastern grey squirrels found throughout the city of Calgary are descendants of escapees from the Calgary Zoo and pets from the 1930's. When I visited the Jurong Bird Park in Singapore I saw free-ranging green iguanas, although I don't know if the population there is breeding and whether it originated from the Jurong Bird Park or elsewhere.
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I have been wrestling over the question of whether zoos should display potentially invasive species.
Invasive species are a major contributor to the loss of biological diversity. The IUCN considers invasive species as the second most common cause of the historical extinction of species and the most common contributing factor to the threat of extinction of mammals, reptiles, and amphibians (Invasive species) . Threats to biodiversity from invasive species can include direct predation, out-competing native species for finite resources, carrying and spreading diseases, and preventing reproduction. Invasive species can even indirectly threaten species by changing food web dynamics. Attempts to control invasive species and limit these threats to biodiversity can also have huge economic costs.
With such detrimental effects it is prudent that we closely examine the risks of introducing species to new environments where they may become invasive. As I noted in post #18 even medium carnivores can escape from AZA zoos and remain unrecovered for significant periods of time. If a breeding population escapes from a zoo and finds suitable habitat it can become established, like the black eastern squirrels in Calgary (Post #18).
Despite these potential dangers many zoos exhibit invasive or potentially invasive species. European zoos have significant populations of raccoon dogs, raccoons, Reeve’s muntjac and other invasive species in Europe. Some AZA zoos display wild boars in provinces or states where they are invasive (Calgary Zoo-Alberta) or have the potential to be invasive species (Minnesota Zoo-Minnesota).
I suspect that many of these zoos display these invasive species because the qualities that make them invasive species also make them well suited to captivity from a care and welfare perspective. They have adaptable diets and often do well near humans. They breed easily. They are well adapted to local climates and don’t need expensive winter shelters. They are often easy to acquire too. Returning to the wild boar example both the Calgary Zoo and Minnesota Zoo display wild boars because they can withstand the cold winters there without extensive shelters, they’re easy to care for, and they were probably easy to acquire.
In addition, these Zoos display wild boars because they help show the diversity of Northern environments. Russia’s Grizzly Coast at Minnesota has a breeding group of wild boars to help showcase the differences between North American and Asian Northern environments and complement nearby displays of large carnivores, like tigers, that prey on wild boars.
Animal selection considerations for zoo displays include welfare, exhibit needs, visitor interest, education, and conservation criteria. There aren’t too many species that have high value for every one of these concerns. Wild boars are not a conservation priority- by a large margin, but they are easy to care for, attractive to visitors, and can help convey educational messages, like the similarities and differences between the environments of Minnesota and Russia.
Returning to the example others made with raccoon dogs I would agree that there is little direct conservation value of displaying them, but I think they still have other display values. They are easy to care for and don’t require very large or complex exhibits. Northern zoos can display them without extensive indoor exhibits. I would also ague that they are of interest to visitors because they’re so cute and a unique species of wild dog. Finally, they can be used for educational messages, like the evolution of canids, and can help promote conservation of their native eastern Asian habitats.
Many invasive species have some good display values, but I don’t think that zoos should display breeding populations of them. Zoos should actively manage reproductive potential. This would help prevent threats to biodiversity if zoo animals escape. Zoo populations can be supplied from the abundant populations of invasive species outside their native ranges.
I believe that zoos can display invasive or potentially invasive species, as long as they are properly managed and satisfy animal collection considerations.
Invasive species are a major contributor to the loss of biological diversity. The IUCN considers invasive species as the second most common cause of the historical extinction of species and the most common contributing factor to the threat of extinction of mammals, reptiles, and amphibians (Invasive species) . Threats to biodiversity from invasive species can include direct predation, out-competing native species for finite resources, carrying and spreading diseases, and preventing reproduction. Invasive species can even indirectly threaten species by changing food web dynamics. Attempts to control invasive species and limit these threats to biodiversity can also have huge economic costs.
With such detrimental effects it is prudent that we closely examine the risks of introducing species to new environments where they may become invasive. As I noted in post #18 even medium carnivores can escape from AZA zoos and remain unrecovered for significant periods of time. If a breeding population escapes from a zoo and finds suitable habitat it can become established, like the black eastern squirrels in Calgary (Post #18).
Despite these potential dangers many zoos exhibit invasive or potentially invasive species. European zoos have significant populations of raccoon dogs, raccoons, Reeve’s muntjac and other invasive species in Europe. Some AZA zoos display wild boars in provinces or states where they are invasive (Calgary Zoo-Alberta) or have the potential to be invasive species (Minnesota Zoo-Minnesota).
I suspect that many of these zoos display these invasive species because the qualities that make them invasive species also make them well suited to captivity from a care and welfare perspective. They have adaptable diets and often do well near humans. They breed easily. They are well adapted to local climates and don’t need expensive winter shelters. They are often easy to acquire too. Returning to the wild boar example both the Calgary Zoo and Minnesota Zoo display wild boars because they can withstand the cold winters there without extensive shelters, they’re easy to care for, and they were probably easy to acquire.
In addition, these Zoos display wild boars because they help show the diversity of Northern environments. Russia’s Grizzly Coast at Minnesota has a breeding group of wild boars to help showcase the differences between North American and Asian Northern environments and complement nearby displays of large carnivores, like tigers, that prey on wild boars.
Animal selection considerations for zoo displays include welfare, exhibit needs, visitor interest, education, and conservation criteria. There aren’t too many species that have high value for every one of these concerns. Wild boars are not a conservation priority- by a large margin, but they are easy to care for, attractive to visitors, and can help convey educational messages, like the similarities and differences between the environments of Minnesota and Russia.
Returning to the example others made with raccoon dogs I would agree that there is little direct conservation value of displaying them, but I think they still have other display values. They are easy to care for and don’t require very large or complex exhibits. Northern zoos can display them without extensive indoor exhibits. I would also ague that they are of interest to visitors because they’re so cute and a unique species of wild dog. Finally, they can be used for educational messages, like the evolution of canids, and can help promote conservation of their native eastern Asian habitats.
Many invasive species have some good display values, but I don’t think that zoos should display breeding populations of them. Zoos should actively manage reproductive potential. This would help prevent threats to biodiversity if zoo animals escape. Zoo populations can be supplied from the abundant populations of invasive species outside their native ranges.
I believe that zoos can display invasive or potentially invasive species, as long as they are properly managed and satisfy animal collection considerations.
In the continental United States I feel that the list of invasive vertebrate species which have any capacity for significant damage to native ecology, which are not already causing problems now, is incredibly small. Zoos now are more secure than ever before, and if an animal didn't already escape in the past two centuries it's very unlikely to manage to do so in sufficient numbers to establish itself now.
The only naturalized zoo escapes in this country I can recall are the macaques in Florida - just about everything else descends from privately owned pets or animals being imported to the pet trade (feral parrots, pouched rats, Burmese pythons) or intentional releases for whatever reason (sparrows, pheasants, game antelopes)
The worst one for the environment in this country is the cat. Enormous populations that can exist independent of local food availability coupled with a widespread decline of larger limiting predators has produced the perfect invasive predator able to drastically damage native ecosystems. But cats are here to stay and nobody is pushing to ban them.
And even the cat is not killing off whole species, genera of songbirds on mainland North America - a few species are threatened, but overall, they are not causing extinctions here as they have on isolated insular environments with no native predators. They are an increased pressure on small animal species but they are a pressure that local prey are adapted to, as there are many predatory small mammals native already (raccoons, opossums, foxes, bobcats, weasels, etc).
The raccoon dog is, to our environment, another fox or something between one and a raccoon. It's not even a particularly well-adapted fox, superior in any respect to our native ones. If they were importing these guys to the New Zealand pet trade, I'd be afraid. But to an AZA zoo in the continental US? This is a region where even a release of a breeding group would almost certainly have no substantial ecological effects. It's a species that does nothing that native carnivores don't already do, and that native prey can deal with. To call it a disease vector is fear-mongering, given that some of the worst carrier animals for rabies are already superabundant, one native (the raccoon) and one our coddled and adored house cat. The raccoon dog isn't any more prone to rabies than any of the other carnivores in North America, and it's probable that feral raccoon dogs would be less closely associated with us (not nesting in our ceilings and crawlspaces, like raccoons, or sleeping on our beds like cats) so we'd be even less likely to be in close contact to a rabid one.
The only naturalized zoo escapes in this country I can recall are the macaques in Florida - just about everything else descends from privately owned pets or animals being imported to the pet trade (feral parrots, pouched rats, Burmese pythons) or intentional releases for whatever reason (sparrows, pheasants, game antelopes)
The worst one for the environment in this country is the cat. Enormous populations that can exist independent of local food availability coupled with a widespread decline of larger limiting predators has produced the perfect invasive predator able to drastically damage native ecosystems. But cats are here to stay and nobody is pushing to ban them.
And even the cat is not killing off whole species, genera of songbirds on mainland North America - a few species are threatened, but overall, they are not causing extinctions here as they have on isolated insular environments with no native predators. They are an increased pressure on small animal species but they are a pressure that local prey are adapted to, as there are many predatory small mammals native already (raccoons, opossums, foxes, bobcats, weasels, etc).
The raccoon dog is, to our environment, another fox or something between one and a raccoon. It's not even a particularly well-adapted fox, superior in any respect to our native ones. If they were importing these guys to the New Zealand pet trade, I'd be afraid. But to an AZA zoo in the continental US? This is a region where even a release of a breeding group would almost certainly have no substantial ecological effects. It's a species that does nothing that native carnivores don't already do, and that native prey can deal with. To call it a disease vector is fear-mongering, given that some of the worst carrier animals for rabies are already superabundant, one native (the raccoon) and one our coddled and adored house cat. The raccoon dog isn't any more prone to rabies than any of the other carnivores in North America, and it's probable that feral raccoon dogs would be less closely associated with us (not nesting in our ceilings and crawlspaces, like raccoons, or sleeping on our beds like cats) so we'd be even less likely to be in close contact to a rabid one.