To Zoo or Not to Zoo: What to Do About Husbandry-Challenged Species?

[Coelacanth18]

It seems clear that husbandry practices are more successful for some species than for others. Zoos are very good at keeping some species alive and breeding them, while other species have never fared well in captivity for a variety of reasons. While many hard-to-keep species may be of little concern, others are endangered and could stand to benefit from ex situ management if the husbandry was successful; unfortunately, this is often not the case. Furthermore, establishing captive populations when the species is already in a precarious state is risky (case in point: Sumatran rhino).

With that being said, it is also true that husbandry develops over time. It was once very hard for zoos to keep gorillas alive, let alone breed them, but eventually zoos got the hang of it and now the husbandry for gorillas is very well-developed. That expertise and husbandry knowledge required quite a bit of trial-and-error in order to succeed; had it not been done, however, gorillas would not be the mainstay of major zoos around the world like they are today.

So my question is this: are there species for which we should accept that captive management is too problematic to pursue? Perhaps we only need more husbandry knowledge and expertise to make it possible to keep them; on the other hand, perhaps there is a challenge with keeping that species for which there is really no good solution. Obviously, this might vary in a case-by-case basis (and I would love to hear any number of those), but the root of what I'm getting at is whether developing good husbandry technique is simply not possible for some species.

 

[FunkyGibbon]

A couple of basic points:
I think these days people are not prepared to accept large numbers of deaths whilst that 'feeling out' process is undertaken. This site may be more 'bullish' on that issue than most communities though.
People probably would accept the deaths if there was a demonstrable need to establish a captive population (assuming an ex-situ modelof conservation). However, endangered populations almost by definition can't afford lots of losses in this way, so that's also a non-starter.
Just by pure logic then, the only cases where people might accept large-scale losses are either species where there a currently large numbers but we know there will be a large population decline, or species where numbers are already low, and extinction is seen as inevitable.
Especially in the second case people are, I assume, pretty wary of being the one who 'killed off' the last of a species, even if extinction was inevitable anyway.

 

[Coelacanth18]

@FunkyGibbon : I see your point about the trial-and-error process being more controversial today than it may have been in the past. Along with your points about endangered species not being in a good position to sustain further losses, I agree that probably it should only be done if it is necessary to the survival of that species (or if it can be demonstrated that the gains will outweigh the losses). However, I think that one could make that argument for a number of species that have demonstrated husbandry challenges in captivity. Of course, that would introduce a new question, which is: at what point do we decide that it's necessary?

 

[JVM]

This is a great question! I think a key reason for these failures is how many species were imported to multiple facilities around the same time, only for numbers across the wider gap to die out, often persisting in only a few key institutions, as happened with River dolphins and Sumatran rhinos. I think it would be better to import a few individuals to a single facility that is prepared to make a long-term investment in the species and is willing to coordinate with ex-situ programs to further research - and if that facility can succeed, the research can be extended elsewhere, versus importing the species to a dozen locations and hoping they can all figure things out.

 

[Coelacanth18]

@JVM : Thanks! I think you make a very good point. I've heard of that strategy being used for a few species in Europe (and a few in the US as well), and while the progress can be slow it can be quite effective.

 

[TeaLovingDave]

I think it would be better to import a few individuals to a single facility that is prepared to make a long-term investment in the species and is willing to coordinate with ex-situ programs to further research - and if that facility can succeed, the research can be extended elsewhere, versus importing the species to a dozen locations and hoping they can all figure things out.

Something which has been done pretty successfully at Leipzig with Eastern Quoll, and which they hope to replicate with Greater Bilby in the coming years. Copenhagen looks to be planning something along these lines with Tasmanian Devil, too.

 

[gentle lemur]

We have to accept that some species cannot be kept successfully in zoos and aquaria, for the foreseeable future at least. These include species such as pelagic seabirds, swifts and leatherback turtles which have specific requirements for space, environment or diet that cannot be met. There are other species which are difficult to keep ex situ, but may succeed in captivity in situ or in zoos where environmental conditions resemble those in their natural habitat, for example montane species like the volcano rabbit seem to do better at high altitudes (as at Chapultec Zoo in Mexico City). There are also species that might do well under lab conditions, but will probably never go on show in a zoo, such as golden moles.
It is interesting to consider the examples of some species which are currently at the start of their history in captivity. The Madagascar pochard is at the earliest stage, with in situ captive rearing and breeding by a joint Durrell and WWT team, with the support of the Malagasy government, and the prospect of using captive bred birds to establish a second wild population. However there seem to be very few suitable places left for wild birds of this species: so if numbers are to continue to increase, this species may need an ex situ population in a few years times.
The WWT also works with the spoon-billed sandpiper and a small ex situ group has been established at Slimbridge. This part of the programme is still experimental and perhaps husbandry techniques are not yet perfect, because the first hatchings occurred this year but the chicks failed to survive. Fortunately, captive rearing and release of chicks in situ, followed by education and protection measures on the birds' migration routes and wintering grounds, seem to have stabilised the number of wild birds. It is possible, but by no means certain, that a zoo population of this species may become established eventually.
The Javan green magpie is one step further along the path, the breeding programme started in 2011 at the Cikananga Wildlife Centre in Java, using birds from bird markets. This centre is supported by a number of zoos in Europe and America, with Chester Zoo taking a lead role in the magpie programme. In 2015, 6 pairs of magpies were taken to Chester, with some going on to Prague and Jersey. This year 4 birds were raised off-show at Chester, and it is possible that some birds will go on show next year.

 

[Coelacanth18]

Something which has been done pretty successfully at Leipzig with Eastern Quoll, and which they hope to replicate with Greater Bilby in the coming years. Copenhagen looks to be planning something along these lines with Tasmanian Devil, too.

Good examples. I also thought of Leipzig but for Chinese pangolins, and of Newquay for Owston's palm civet.

 

[Coelacanth18]

@gentle lemur : All very good info, thanks. In terms of keeping pelagic species like leatherback turtles, would you say that also precludes large fish like whale sharks, manta rays, and ocean sunfish?

 

[gentle lemur]

@gentle lemur : All very good info, thanks. In terms of keeping pelagic species like leatherback turtles, would you say that also precludes large fish like whale sharks, manta rays, and ocean sunfish?

These species all need a lot of space. Mola mola and the leatherback eat jellyfish, the sunfish can be trained to take other food and has been kept quite successfully I believe, but as far as I know the leatherback hasn't and it would take a vast amount of jellyfish to nourish a moderately sized specimen. Whale sharks and manta rays are plankton feeders and so they could be fed, but the rays are fast swimmers and can jump.
The faster swimmimg pelagic fishes like swordfish, tuna and dolphinfishes might be more difficult, but tarpon seem to do OK in large tanks.
I was also thinking of pelagic seabirds, like albatrosses, fulmars, shearwaters and petrels. It might be possible to keep some of the smaller species, but I've never heard of it.

 

[Giant Panda]

@gentle lemur: I don't know much about the situation with birds, but given your thoughts on pelagic species, what's your opinion on keeping, say, vultures in aviaries which will never realistically allow them to soar? Also, if we accept the "behavioural need" of a pelagic seabird to travel long distances, what about terrestrial species that do likewise? The comparative analyses that have been performed indicate that wide-ranging primates and carnivores both fare worse in captivity...

And to illustrate @FunkyGibbon's "basic points" with some examples and (non-bullish) notes:

Small populations that can "afford lots of losses": Double-clutching and cross-fostering may even increase reproductive output, eg. Chatham Island robins, Mauritius kestrels, and brush-tailed rock wallabies. We can also use models to predict both the impact of removing individuals on wild populations and the likelihood of establishing a sustainable captive breeding program (Ark or park: the need to predict relative effectiveness of ex situ and in situ conservation before attempting captive breeding). For example, what are the demographic consequences of removing x individuals from a population of y size given z parameters?

Abundant species expecting declines: Models based on IPCC projections can tell us which species are most vulnerable to global warming. One analysis concluded that only 21% of birds predicted to go extinct under climate change are currently threatened (http://www.uam.es/personal_pdi/ciencias/jspinill/BIBLIOGRAFIA_CASO/CB_2008_22_140_150.pdf). Time to pre-emptively start breeding the common ones?

*Quietly retreats*

 

[CGSwans]

Pangolins are the species I would think are most appropriate for an attempt at a large-scale, Sumatran rhino-style ex-situ intervention. There is still a sizeable population in the wild of several species, although obviously under immense pressure, so removing animals doesn't necessarily foreclose in-situ efforts. They have already been kept successfully - or at least - kept alive - at Night Safari, San Diego, Ueno and Leipzig, so the first hurdle to captive success has been cleared. They are so heavily trafficked that I imagine opportunities to boost the captive population will come from animals being intercepted from smuggling attempts, that are probably facing very uncertain fates upon release in any case. And finally they are relatively small, so it's easy to see how 50-100 zoos across Europe and North America could support 4-8 animals each.

 

[Coelacanth18]

@Giant Panda : Thanks for those examples. While I'll let gentle lemur speak for himself about what he meant, I interpreted his points about pelagic species to be more about physical needs than behavioral needs. Some large pelagic animals will simply not survive long if kept in an enclosure; a vulture that is denied the opportunity to soar may not be living optimally, but that doesn't mean they cannot be kept that way. The vulture will live (and quite probably breed) for decades, whereas a pelagic shark will typically live for a few months, if even that.

 

[Giant Panda]

@Giant Panda : Thanks for those examples. While I'll let gentle lemur speak for himself about what he meant, I interpreted his points about pelagic species to be more about physical needs than behavioral needs. Some large pelagic animals will simply not survive long if kept in an enclosure; a vulture that is denied the opportunity to soar may not be living optimally, but that doesn't mean they cannot be kept that way. The vulture will live (and quite probably breed) for decades, whereas a pelagic shark will typically live for a few months, if even that.

Quite possibly (that's why I began my post as I did), but I think ignoring behavioural needs is fallacious. It's a controversial topic, but these are behaviours animals are strongly motivated to perform even when the motivator itself is absent or unnecessary. If long-distance travel were a behavioural need for a species, and I think the evidence either way is lacking for most taxa, it would raise questions over our ability to satisfactorily keep that species in captivity. Food for thought.

 

[gentle lemur]

I think it's important to realise that each species may pose a different set of problems. I was generalising before when I talked about the problems posed by pelagic species. In some cases they could simply need a lot of space, in others they might require specialised diets or special methods of food presentation. Quite possibly some species need salt water or at least trace elements, some could be very sensitive to poor water quality. Albatrosses may need steady winds and a water surface with a consistent swell to fly properly. Scientists who have studied these species may be able to provide clues, but the husbandry of a new species is always going to be an experiment that may fail.
But even if you can keep an animal alive for its natural lifespan, you may not be able to breed it successfully. Even closely related species may have very different breeding systems and respond to different social or environmental cues.
I have personal experience from the time when I first started to keep Tanganyikan cichlids. I was particularly interested in the goby cichlids and I happened to visit the UK's only importer just after a shipment of these fascinating fishes had arrived. They were little known at the time and although this dealer probably knew more about Rift Valley cichlids than anyone in the country, he wasn't even sure which of the four known species they belonged to as this shipment had come from a new area of the Lake.
We did know that these species are mouthbrooders, so he advised me to take a large one and three smaller ones; hoping to get a group of 1:3 fishes, which is the standard practice for Rift Lake mouthbrooders, where polygamous males can serve large of numbers of females, who then swim away to incubate their eggs in isolation.
The following morning, I was horrified to find that the smallest fish had been killed overnight and a second had been badly injured (although it recovered after I removed it to another aquarium). I felt dreadful, and the only compensation for this unnecessary loss was that I was able to send the corpse to Humphrey Greenwood at the Natural History Museum, who identified the species as Eretmodus cyanostictus. A few days later I was able to return to the dealer to tell him that these fishes ought to be kept in pairs and to buy another female to pair with the convalescent fish, who seemed to be a male.
The reason for this unusual behaviour became clear when the original pair spawned, because I was able to witness their unique behaviour. The pair chose an isolated stone as their spawning site and the female incubated the eggs for about 2 weeks (half of the typical mouthbrooder term). Then she swam back to the spawning site and displayed to the male, before spitting out the larvae, one or two at a time, so that he could take them up and complete the incubation of the clutch. This breeding system is called biparental mouthbrooding and it requires these fishes to live in monogamous pairs: which explains why my original pair attacked the other two fishes. Subsequently both of my pairs bred several times and I was able to rear many healthy fry.

 

[vogelcommando]

This is quite a complex thread and I have also some remarks and thought about the subject :
to take threatened / rare animals from the wild to bring them into zoos to do experiments to find out the best way of husbandry and breeding seems to me a bad idea but at the moment there are so many animals avaible at resue-centres ( mostly confistigated animals ) that a part of these animals could be brought to zoos which already have had some experience with the given ( or closely releated ) species. The benefit would be double - the rescue-centers got some more space for the animals still left ( and place avaible for new confistigations ), the zoos with some experience could gain more experience and made this information avaible to other zoos ( AND resucue-centers ). If animals die -which is of course well possible in animals about which little is known about captive husbandry ! - it's of course a real pitty but on the other hand - these specimens were lost for the wild population already.
The above has already be done - and proofed to be succesfull - with several species like Owston's palm civet, Philippine spotted deer and several Asian turtles and tortoise-species but also species like the pangolins, slow lories, loads of bird-, reptiles and amphibian species could benifit from such projects !
Now some notes on species mentioned already above :
Pelagic seabirds : very little experience has been gained with those species and therefor here also, if any are brought to rescue-centers, bring some of them to zoos so they can start to find out the best way to keep them.
Pelagic fish-species : I think several marine-institutes are working on these species to find out if its possible to raise some species in marine aqua-farms and large Aquariums and zoos with large aquariums could ( should ) try to cooperate with such institutes to find out husbandry-protocoles for captive specimens.
Vultures : the greatest captive breeding-succeses have been archieved with both New World ( Californian condor ! ) and Old World vultures ( Bearded, Griffon vulture ). Captive bred birds are roaming again in nature. Without captive breeding the Californian condor for example had been lost forever.
Pangolin : Has already mentioned above, loads of them are kept in quite poor conditions in rescue-centers in ( mainly ) Asia and it would be very wise to bring at least a part of these animals to a number of zoos which already have some experience with those animals. I'm sure a way can be found to figure-out how to keep and breed these species - first succeses already have been archieved - and with some financial support from the recieving zoos, also the rescue-center can improve the husbandry of the animals in their care.
Not mentioned sofar are the coral-fishes: only a very small amount is bred succesfully in captivity and here a lot has to be done to change this. In this case ( IMO ) zoos have to cooperate with private-keepers and marine research institutes to find ways how to breed at least some of the species.
Another group not mentioned sofar are the Hummingbirds, a family which has done very poor sofar in zoos.There are some - very succesfull - privat breeders and zoos would do very wise to try to learn from them how to keep and breed these birds !

 

[Hyak_II]

These species all need a lot of space. Mola mola and the leatherback eat jellyfish, the sunfish can be trained to take other food and has been kept quite successfully I believe, but as far as I know the leatherback hasn't and it would take a vast amount of jellyfish to nourish a moderately sized specimen. Whale sharks and manta rays are plankton feeders and so they could be fed, but the rays are fast swimmers and can jump.
The faster swimmimg pelagic fishes like swordfish, tuna and dolphinfishes might be more difficult, but tarpon seem to do OK in large tanks.
I was also thinking of pelagic seabirds, like albatrosses, fulmars, shearwaters and petrels. It might be possible to keep some of the smaller species, but I've never heard of it.

I can help answer some of these!

The singular most successful attempt at Leatherback captivity was by UBC in Canada. They managed to keep one alive for at least 3 years, on a diet consisting mainly of gelatin enhanced with vitamins and minerals. It was also fed small amounts of squid. The biggest issue is their complete inability to deal with barriers, captive animals need to be kept tethered at all times to avoid coming into contact with tank walls or bottoms.

Whale sharks have proven to be decently adaptable to captivity, with several collections in China and Japan housing at least 10-15 combined indivduals, and Georgia with their 4. Their ability to feed while stationary and also avoid barriers while swimming gives them a massive advantage over most other pelagic sharks, which much like the leatherbacks are simply unable to comprehend barriers effectively. To my knowledge the only facility currently housing a strictly pelagic species is Sendai Umino-Mori Aquarium in Japan, with a fairly good sized pair of Blue Sharks. Sadly both animals are looking rather worse for wear, and while both seem to be able to deal with the tank wallls at this point, they show many wounds from encounters with tank walls (smashed rostrums, sores and wounds on pectoral fins, etc...)

Now Manta rays are a different story. While there are very few facilities holding them (Georgia in the US and Okinawa in Japan are the main two that come to mind), they actually adapt superbly well to captive life. They pick up on feeding from cups very quickly, and they show good barrier avoidance. In fact, they do so well that Okinawa has actually had breeding success, with at least 4 pups, if not more being born, and I believe all but the first (which was killed by another manta) are all still alive. They singular biggest factor that hinders them from spreading in the aquarium world is their sheer size and the amount of space needed to house them.

Pelagic fish are iffy, but most of the big ones (Tuna, Dolphinfish, Billfish, etc..) have been attempted with decent levels of success, mainly in Japan or in Aquaculture/research facilities in the US. The key with them is lots of run space or a system that lets them unidirectionally constantly.

Pelagic birds are another tricky one. There are very few because, simply put, they make poor display animals. When on land they tend to simply sit or perch in one area, and move little, which can make them prone to foot issues like bumble foot. However the full array (Albatross, Shearwater, Petrel, Booby, Tropicbird, Frigate Bird, Terns, Gannet, Giant Petrel) have been kept with varying levels of success. Of course many of these birds arrive as un-releasable rescue birds, which generally puts them at a disadvantage due to compromised health and the stressful methods which they enter captivity. Boobies, Gannets and Giant Petrels have all bred successfully, and not surprisingly the Boobies and GP's were all collected as eggs or young chicks, giving them a significant advantage to adapting to captive life.

 

[Coelacanth18]

@Hyak_II : Thanks for all of that info Hyak! I'm glad that manta rays and whale sharks both do well in captivity; I saw both of these species when I visited the Georgia Aquarium, and while most people make a big deal of the sharks, I was equally enamored with the mantas. Both of these species are threatened as well, although due to the space requirements I'm not sure if captive management would ever be a viable option for these species.

Would anyone be willing to explain to me the differences between pelagic birds and coastal birds? In my head I just lump all of them together as sea birds, and as such I have been confused by why there are husbandry issues, considering that we keep many coastal birds in captivity very easily.

 

[Hyak_II]

No problem! I'll also have to agree, while whale sharks are very cool, the Mantas definitely rank just as high, if not more so for me. I could potentially see the rays taking a bit of a foot hold if more breeding occurs, but whale sharks I think are fairly close to max holding capacity.

Also I can help with your other question, as well! Essentially, coastal birds are birds that, well, live on the coast. Sandpipers, most gulls, most plovers, certain terns, and pelicans are all good examples. Basically these birds spend decent amounts of time on land, usually stay closer to shore, and are usually fairly capable of walking well. On the other hand, pelagic birds, like Boobies, Alcids, Petrels, Albatross, Tropicbirds, certain terns, and to a lesser extent Kittiwakes, are a bit different. They generally only come to land to breed, sleeping either on the wing or on the water for most of the year. They tend to range much farther out to sea, and may not come close to land for weeks at a time. They are also much less capable on land, usually having to scoot around almost on their stomachs or waddle around preposterously. Essentially they are adapted to either be flying or swimming, as opposed to spending time on land.

 

[gentle lemur]

I can help answer some of these!

Thank you very much for all these details. I'm afraid UK aquaria are all much too small for these fishes etc and we are well behind the curve with all these species, so I have little detailed knowledge.
Some of the seabird species are kept here and I agree with your assessments - cormorants, waders (shorebirds), sea ducks, skuas, gulls & terns and gannets can generally be kept successfully (although some species may pose particular problems). I hadn't heard about giant petrels, but I am not surprised as I remember seeing a sheathbill thriving at Regent's Park many years ago. Auks are more difficult, but they can be kept successfully now. As has been said earlier in this thread, the other species have mainly been kept as rescued individuals and I am sure that a body of knowledge about them is being built up. However that is not quite the same thing as a successful zoo exhibit. I find it hard to imagine one for most of these species.
I think one the saddest sights I have ever seen at a zoo was in an old black and white BBC TV programme presented from Bristol Zoo by the late James Fisher (a quick search on Google suggests it may have been 'News from the Zoos' transmitted 25th March 1959 or possibly from his later series 'World Zoos' in 1961); there was a shot of three frigate birds squatting uncomfortably on the ground, they were quite obviously not in a aviary and unless they were rescued individuals, they had either been wing-clipped or pinioned. I don't know if anyone knows more about these specimens.