What goes into deciding a phase-out?

tigris115

Well-Known Member
10+ year member
I know that phase outs in zoos can sometimes come off as arbitrary or even cruel but I never like jumping to conclusions so I'd like to ask if anyone here knows what specifically goes into making the decision to phase out a zoo species, especially in the AZA.

I also ask that you all make at least some attempt to talk with respect and with courtesy. You are all adults and thus I expect you to act as such. This may come off as overbearing but I've seen discussions spiral into hell before so I'm preventing it the best I can.
 
Every few years, each TAG is required by AZA to produce a Regional Collection Plan. As part of the RCP, a decision tree is used to determine what level of management, if any, a species will receive. The tree uses a variety of factors, such as prevalence within AZA, genetic sustainability of the current population, likelihood of future imports (either from the wild or from outside zoological entities), related taxa being managed within AZA, conservation status, whether the species is focused on in another geographic region (such as EAZA), etc. This is the document that usually defines a species as a phase out.

A phase out species is generally one which is a) not sustainable due to demographics and genetics, and b) there is not interest in managing on a large scale. I'd say item B is usually the key driver. It's worth noting that the RCP isn't binding per se, and zoo's have a considerable amount of autonomy. If a zoo wants to continue to work with a species that the TAG wants to phase out, they are free to do so, as evidenced by Bronx's work with gaur, for example. They just have to follow ethical acquisition protocols, as defined by AZA accreditation standards.
 
What are some of the factors that play into lack of interest?

Because I feel that there should be some interest in not having everything super monotonous, especially for threatened and endangered species.

As well, I think too many phase outs can be used as a weapon by the antis, since they can say "Zoos only care about the basic cute stuff."
 
What are some of the factors that play into lack of interest?
Lack of interest can be caused by a lot of factors. A non-exhaustive list includes:
  • The high cost of keeping (and feeding) a particular species.
  • A species generally not breeding well in captivity.
  • A species being a relatively poor exhibit animal- think very shy/seclusive species, fossorial species that live their entire lives underground, etc.
  • Limited space in a zoo. As zoos focus on improving welfare and having larger homes for species, they inevitably need to make tough choices as to what species they will stay committed to.
  • Difficulty acquiring new individuals of a particular species.
  • A species filling the same niche as another species that, for whatever reason, is easier to manage and/or has stronger exhibit/education/conservation value.
While there are certain species (particularly a few species of old world monkeys) that I am rather critical of the lack of AZA interest and support for, overall I will say that there are normally extremely good reasons for a phase out, and the decisions aren't made lightly.
 
While there are certain species (particularly a few species of old world monkeys) that I am rather critical of the lack of AZA interest and support for, overall I will say that there are normally extremely good reasons for a phase out, and the decisions aren't made lightly.
Oh I'm sure there are a ton of good reasons for phasing out a species. Especially as a lot of times, animals can have quirks that us guests don't see but make their upkeep a royal pain. For example, I recall one member (greater kudu pfp) saying that gaur are mean and flighty as hell. Though cape buffalo aren't being phased out and iirc, they're hellish in their attitude

Tho it is also very, VERY hard to not play favorites with some critters.
 
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Lack of interest can be caused by a lot of factors. A non-exhaustive list includes:
  • The high cost of keeping (and feeding) a particular species.
  • A species generally not breeding well in captivity.
  • A species being a relatively poor exhibit animal- think very shy/seclusive species, fossorial species that live their entire lives underground, etc.
  • Limited space in a zoo. As zoos focus on improving welfare and having larger homes for species, they inevitably need to make tough choices as to what species they will stay committed to.
  • Difficulty acquiring new individuals of a particular species.
  • A species filling the same niche as another species that, for whatever reason, is easier to manage and/or has stronger exhibit/education/conservation value.
While there are certain species (particularly a few species of old world monkeys) that I am rather critical of the lack of AZA interest and support for, overall I will say that there are normally extremely good reasons for a phase out, and the decisions aren't made lightly.

Health is another big one, especially with primates.
 
Health is another big one, especially with primates.
Yes, I am aware of some examples of this. As I said that was a non-exhaustive list of possible reasons for phase outs, as in reality every decision is made individually, and there are plenty of different reasons. Another one not mentioned that's quite common is a low founder base and inbreeding depression.
 
It's an unsatisfying and not very scientific answer, but from personal experience, I can't over-emphasize the role of personal preference for staff as well. If you have a bird curator who really is into psittacines or waterfowl or pheasants, than that's what your collection is going to show a bias towards, sometimes a very strong bias (I had a herp curator I worked with who had zero interest in anything that wasn't either a) a varanid or b) venomous). If that person leaves the institution, the collection can change very suddenly to reflect the interests of whoever replaces them.
 
As well, I think too many phase outs can be used as a weapon by the antis, since they can say "Zoos only care about the basic cute stuff."

A large portion of the total species held by zoos are either marked as "phase out," "not recommended," or are not monitored at all - the AZA formally manages only a tiny percentage of the total species in their care.

For example, I recall one member (greater kudu pfp) saying that gaur are mean and flighty as hell. Though cape buffalo aren't being phased out and iirc, they're hellish in their attitude

Cape Buffalo are walking the phase out line as it is. The difference with Gaur being there's another very similar Asian bovid that was competing for space with Banteng. For space reasons, it was one or the other for formal management.

It's an unsatisfying and not very scientific answer, but from personal experience, I can't over-emphasize the role of personal preference for staff as well. If you have a bird curator who really is into psittacines or waterfowl or pheasants, than that's what your collection is going to show a bias towards, sometimes a very strong bias (I had a herp curator I worked with who had zero interest in anything that wasn't either a) a varanid or b) venomous). If that person leaves the institution, the collection can change very suddenly to reflect the interests of whoever replaces them.

I've heard many times this is one of the biggest reasons a program or group can take off or sink like a rock. It often comes down to what the curators want to work with more than anything.
 
Well I do hope there's still some institutional interest in ungulates because those are my favorites if we're playing that game.

There is, though it also depends on the type of ungulates we're talking about. A lot of smaller species are falling out of favor currently.
 
Is there any AZA talk about "oh crap, we might all be homogenized?"

My understanding is there is some discussion about the issue of many curators only wanting to hold managed species, yes. I don't know any real specifics.
Conversely, a good degree of homogenization is necessary for stable long-term populations and the AZA wants zoos to be holding these species (eg. Red Panda, Meerkat.) Stable, genetically healthy populations and SSPs versus homogenization of collections is a very nuanced discussion as far as mammals and birds are concerned. Herps, fish, and invertebrates are a lot more of a wild card.
 
Is there any AZA talk about "oh crap, we might all be homogenized?"

A lot of curators, senior keepers are very similar as many people on this forum. They like animals, they like to visit zoos and they like to see new species. So yes there is this talk, but there is also the professional realisation that homogenisation is needed for the reasons Great Argus mentions. This tension is present in the process and like in all processes there is what we want, what is needed and what is feasible and they are in most cases not the same.

All in all what I've seen is that personal preference plays a key role in decisions on which species to manage and which not all though factors are at play that are often not widely known outside the people working closely with it. A species I work with was considered extinct in the wild and was briefly part of a programme, but suddenly a lot of zoos got rid of it and the programme was discontinued (although some zoos did continue keeping and breeding the species and they are the reason they are still around). The species is colourful and visitors like to see them, but what happened. Firstly there were big questions about the purity of the taxon and finding out which birds were not mixed with related taxa would have been a lot of work and quite a high investment money wise. Secondly there was a disease aspect where a significant part of the population carried a virus that could transmit to related species. For many not so committed zoos this burden was too high so the interest dropped to those really passionate about it and willing to invest the time and money in resolving these issues.
 
A genetically stable population almost inherently requires the maximum number of spaces and holders to support the genetic diversity of a species overall; as many holders as possible will need to be able to support the breeding program to maintain this genetic diversity; complex breeding programs will usually require multiple spaces per holder, raising the cost and overall commitment to keeping the species.

When the cost and commitment are too high for a large enough number of zoos to bear, or compete directly with another supported program, a species population tends to become unsustainable, and those are the species that become phase-out species.

Oh I'm sure there are a ton of good reasons for phasing out a species. Especially as a lot of times, animals can have quirks that us guests don't see but make their upkeep a royal pain. For example, I recall one member (greater kudu pfp) saying that gaur are mean and flighty as hell. Though cape buffalo aren't being phased out and iirc, they're hellish in their attitude
Cape Buffalo are not being phased out in any formal capacity but they are largely remaining consistent with the same handful of holders with no likelihood of expansion, partly for the reasons you mention.
 
Is there any AZA talk about "oh crap, we might all be homogenized?"
For starters, I think you have to define homogenized. Complete homgoenization where every zoo holds the exact same species is never going to happen, there will always be nuances and differences between facilities. For example, gorillas, chimps, both orangutans, and three species of gibbon are all being actively managed by the AZA, and while each is fairly common, it's not like every single zoo is holding seven species of ape. While it'd be great to see more interest in, say, managing four or five gibbon species instead of three, it's simply not realistic especially since in pair-living species a large number of holders are needed to make a population sustainable. If five zoos each keep thirty penguins, you might have a pretty stable, sustainable population, the same cannot be said if five zoos were keeping a pair of gibbons. While yes, there are species I wish were kept by more zoos, the idea that only a small number of species are held by all zoos is in many cases overblown as well.

Some things though have been done to kind of counteract this homogenization. Some SSPs in recent years have been merged, with one SSP Coordinator working with a few closely related species. Examples of where this is happening include gibbons, orangutans, spider monkeys, tigers, and red pandas. What this does is it balances the interest in a particular group between species that have extremely similar care requirements and fill the same exhibit niche. For example, if there was a sudden burst of interest in siamangs, the Gibbon SSP could try to help balance that with making sure the other two gibbons have enough holders too, and this prevents a sort of competition between similar SSPs in need of the same, finite number of spaces.

While relatively rare right now, I hope to see that trend of merging SSPs continue in the future. I'd imagine it'd be beneficial to have a Spheniscus SSP to balance the popularity of African penguins with the two South American species, and I'd imagine it could be beneficial for some SSP merges in lemurs to ensure the eulemur species aren't being crowded out by ring-tailed and ruffed lemurs.

Another thing happening is there seems to be more international cooperation nowadays. While sometimes this might increase homgoenization (e.g., sloth bears are being housed primarily in US zoos, but sun bears primarily in European), oftentimes this could help mitigate it. Gene flow between the two continents by swapping individuals can help reduce inbreeding depression, and sometimes there's enough international interest to manage a species that there isn't enough interest at the continental level. While this strategy is limited to species without overly stringent import laws, it remains a beneficial strategy to balance the homogenization of regional zoo associations.
 
It's worth noting that the RCP isn't binding per se, and zoo's have a considerable amount of autonomy. If a zoo wants to continue to work with a species that the TAG wants to phase out, they are free to do so,

May I ask about this part? I've been reading RCPs online (usually old ones because the newer ones aren't available to me as the public), and have found that some of them appear to use stronger language than others, including explicit mention of breeding moratoriums, or assigning staff to enforce/monitor the phase out.

Are these just cases of TAGs getting out too far ahead of what they're officially able to enforce? Or am I reading those terms too strongly and should instead translate them in my head to something more along the lines of "recommendation against breeding" or "assistance with moving a species out"? Or is it more that the TAGs are trying to use maximum non-binding rhetorical power in a way that might persuade and convince all but the most committed zoos away from the species?

I noted that you said phase outs aren't binding "per se", which makes me wonder what hidden levels may or may not be hiding inside of that phrase (ie. you didn't say they weren't binding "at all"). It seems like there might be a spectrum between:
  • completely non-binding recommendations that can be followed or ignored at will
  • recommendations that everyone basically already agreed on at the time and that are included mostly for thoroughness of the taxon, but where enforcement would never become an issue because the recommendation would simply get changed if any zoo really wanted the species
  • recommendations that can't be enforced but are pushed hard to try to persuade zoos to comply
  • recommendations that can't be enforced directly but that get enforced indirectly by making things difficult for zoos that go against the TAG to do other things
  • recommendations that are enforced through social rather than official means (the equivalent of making the zoo an outcast or persona non grata within the TAG, for example)
  • or maybe other options that I'm not thinking of??
I've tried to read through old threads to figure this out, but the accounts of what this means seem to vary wildly. Maybe it's different depending on how powerful or insistent the individual TAG is? Or maybe it's different between AZA and EAZA, and I'm getting them merged and confused in my head? Or maybe this is a case where the full details are only explained depending on where one is within the zoo's organizational chart (ie. a policy that gets listed bluntly when explaining it in a simplified fashion to zookeepers, but where the details are better understood by the curators or directors -- kind of in the same way that accountants or finance folks in a business may give simplified answers to most employees, even if they know there are lots of loopholes that only they deal with)?

Not sure if I've asked this all as clearly as I'd like, but any help getting me closer to clarity would be greatly appreciated!
 
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May I ask about this part? I've been reading RCPs online (usually old ones because the newer ones aren't available to me as the public), and have found that some of them appear to use stronger language than others, including explicit mention of breeding moratoriums, or assigning staff to enforce/monitor the phase out.

Are these just cases of TAGs getting out too far ahead of what they're officially able to enforce? Or am I reading those terms too strongly and should instead translate them in my head to something more along the lines of "recommendation against breeding" or "assistance with moving a species out"? Or is it more that the TAGs are trying to use maximum non-binding rhetorical power in a way that might persuade and convince all but the most committed zoos away from the species?

I noted that you said phase outs aren't binding "per se", which makes me wonder what hidden levels may or may not be hiding inside of that phrase (ie. you didn't say they weren't binding "at all"). It seems like there might be a spectrum between:
  • completely non-binding recommendations that can be followed or ignored at will
  • recommendations that everyone basically already agreed on at the time and that are included mostly for thoroughness of the taxon, but where enforcement would never become an issue because the recommendation would simply get changed if any zoo really wanted the species
  • recommendations that can't be enforced but are pushed hard to try to persuade zoos to comply
  • recommendations that can't be enforced directly but that get enforced indirectly by making things difficult for zoos that go against the TAG to do other things
  • recommendations that are enforced through social rather than official means (the equivalent of making the zoo an outcast or persona non grata within the TAG, for example)
  • or maybe other options that I'm not thinking of??
I've tried to read through old threads to figure this out, but the accounts of what this means seem to vary wildly. Maybe it's different depending on how powerful or insistent the individual TAG is? Or maybe it's different between AZA and EAZA, and I'm getting them merged and confused in my head? Or maybe this is a case where the full details are only explained depending on where one is within the zoo's organizational chart (ie. a policy that gets listed bluntly when explaining it in a simplified fashion to zookeepers, but where the details are better understood by the curators or directors -- kind of in the same way that accountants or finance folks in a business may give simplified answers to most employees, even if they know there are lots of loopholes that only they deal with)?

Not sure if I've asked this all as clearly as I'd like, but any help getting me closer to clarity would be greatly appreciated!

Not very binding at all, to be honest.

TAGs may voice opinions, but at the end of the day, they're just opinions, really. I remember a few years back someone posted on the listserve about some parrots of a non-managed species (very uncommon in US zoos) that were confiscated and needed placement. Within minutes, there was a follow up message from the then-chair of the Parrot TAG, pointedly reminding folks that those weren't a managed species. A major AZA zoo still took them, and that was that.

I'm a studbook keeper. I have (not really, but almost) howled with irritation when I've logged onto facebook and seen yet another zoo cheerfully post pictures of one of several very common, not-managed species that is a direct competitor with my managed species for space. My TAG chair and I can't go to those zoos and say, "Hey, you need to drop X species and start exhibiting Z species." It just doesn't work that way. I can suggest, advise, beg, plead, etc, and sometimes I win a convert or two, but they're all within their rights to hear me out, shrug, and say, "Nah, we're good."

Now, there are rules for the compliance WITHIN the SSP - if your zoo doesn't follow the recommendations - try to breed this animal, transfer this animal, etc - then the SSP and TAG may play hardball (well, a little harder). They may decide not to work with you, not to send you additional animals in the future (assuming you own the animals at your zoo, not much can be done about that), or things like that. Also, whenever a zoo is up for re-accreditation, AZA sends out an email asking if other zoos/program leaders have any objections or concerns about that zoo's conduct, and if so to submit their experiences.

So yeah, not especially binding at all, to answer your question.
 
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