Trends in European zoo collections in the 21st century

[Haliaeetus]

@lintworm
What would be interesting to see what is the percentage of ABC animals vs the "niche" species that help zoos distinguish themselves. And then see if there is a trend of homogenization as often claimed here on the forum. Of course selecting what are the ABC species will be extremely subjective (although could be done by animals kept by at least x amount of institutions) and is there a need to make a distinction between EAZA and non-EAZA zoos (as there has been a view EAZA has been driving this). So many interesting questions, so little time. It does name me appreciate the work you did @lintworm

I haven't got any hard data but I notice that the recent decades have seen the rise of specialized zoos, mainly on popular taxa as cats, primates and even crocodiles and turtles : these zoos can afford many less popular species in their collection plans. In the same time many European fauna themed zoos have risen (I recognize that the concept is extremely large, from comprehensive collections encompassing all taxa to large semi-natural parks with half a dozen species of large hoofstock). In France a few collections (Biotopia Dunkerque, Parc animalier des Pyrénées) have been specialized in French fauna (mainland + overseas territories, primarily Guiana).
Obviously it isn't the solution for every taxa : I haven't never seen any North American nor ungulate-themed zoo in any corner in Europe within the 20 last years (even if both concepts may be very interesting), and such parks seem unlikely to be created in a foreseeable future.

 

[remar]

There are also endangered species without an EEP, but where the zoos involved are part of breeding programs for reintroduction, such as European hamster and Bavarian pine vole.

I hate to correct you, but the comparison of Bavarian pine vole and European hamster is inaccurate. Bavarian pine voles are far away from being released in the wild. If there are still wild animals, which doesn't seem so, there would be even the need of new founders right now. Last summer, the entire known stock (captive and wild) were approximately 25 individuals.

Regarding the statistic stuff. Did you count the dead end species as a loosing species?
I'm wondering, if it would be better to ignore them (dead ends and species lost, that were already dead ends in 90s, which vanished now). For species like the amazon river dolphin or western gorilla their destiny was already decided many years ago, and has nothing to do with the current trend.

 

[Haliaeetus]

I'm wondering, if it would be better to ignore them (dead ends and species lost, that were already dead ends in 90s, which vanished now). For species like the amazon river dolphin or western gorilla their destiny was already decided many years ago, and has nothing to do with the current trend.

Surely Western Gorillas ?

 

[remar]

Most likely not

It never stops to amaze me. You can check your post as long as you want and you still overlook the easiest mistakes.

 

[lintworm]

What would be interesting to see what is the percentage of ABC animals vs the "niche" species that help zoos distinguish themselves. And then see if there is a trend of homogenization as often claimed here on the forum. Of course selecting what are the ABC species will be extremely subjective (although could be done by animals kept by at least x amount of institutions) and is there a need to make a distinction between EAZA and non-EAZA zoos (as there has been a view EAZA has been driving this). So many interesting questions, so little time. It does name me appreciate the work you did @lintworm

I had started with gathering data on which species were kept in 2000 and in 2023 in the Dutch EAZA zoos. That dataset could be used for that, though gathering the exact species kept in especially Artis and Blijdorp in 2000 is quite the challenge as I don't have stocklists. I might still finish that, but it certainly isn't a priority.

I hate to correct you, but the comparison of Bavarian pine vole and European hamster is inaccurate. Bavarian pine voles are far away from being released in the wild. If there are still wild animals, which doesn't seem so, there would be even the need of new founders right now. Last summer, the entire known stock (captive and wild) were approximately 25 individuals.

I should indeed not have written reintroduction, but rather that they are part of a conservation effort outside of an EEP.

Regarding the statistic stuff. Did you count the dead end species as a loosing species?
I'm wondering, if it would be better to ignore them (dead ends and species lost, that were already dead ends in 90s, which vanished now). For species like the amazon river dolphin or western gorilla their destiny was already decided many years ago, and has nothing to do with the current trend.

I did include dead end species as losing species too. If you look at all species that were lost since 2000 most EN & CR animals could indeed be described as dead ends already in 2000, so that would indeed change the narrative a bit.

 

[TeaLovingDave]

Javan warty pig - Sus verrucosus A4
The only suid to be lost this century (yet) is one that has never been on-show. San Diego Zoo planned to import this species and 2.2 animals left Surabaya Zoo, Indonesia, for quarantine in Poznan Nowe Zoo in 1993, but that ended up being their final destination. The final animal passed away in 2004.

Interestingly, I just stumbled across a report *from* Poznan Nowe in one of the back issues of International Zoo News I have been cataloguing over the course of the last year indicating that these individuals were *always* intended to remain at Poznan:

 

[lintworm]

Where rarities appear or disappear

Whereas Europe has thousands of “zoos” and hundreds of EAZA members, it is a relatively select group where new species are first kept or where species are kept last. When ignoring gained-but-lost and lost-but-gained species there are only 55 zoos where a new species for the continent appeared first. With 68 zoos that were the final zoo keeping a certain species, there are slightly more of those.

The top-3 of zoos showing new species is as follows and isn’t very surprising:

1. Zoo Plzen - 18 species

2. Tierpark Berlin - 9 species

3. Zoo Prague - 8 species

The rest of the top-10 is slightly more mixed:

4. RSCC - 6 species

5. Zoo Leipzig, Chester Zoo * Hamerton Zoo Park - 4 species

6. Best Zoo - 3 species

7. Zoo Wroclaw, Poznań Nowe Zoo, Zoo Zuerich, Zoo Ostrava, Zoo Cologne & de Paay - 2 species

This leaves 41 zoos where 1 new species for the century appeared. As a small note some species appeared (near-)simultaneously in multiple zoos, such as Chacoan mara in De Paay and Best Zoo, so these are double counted.

What is apparent is that this is a mix of the usual suspects of Germany, Poland, United Kingdom and Czechia as well as 2 small private Dutch zoos. If one would make a list of which zoos hold the most rarities, many of these places would pop up too.

@Michal Sloviak Saharan striped weasel were one of many mammal species first kept in Zoo Plzen this century

When looking at zoos that were the last to keep a certain species, the top-3 is the following:

1. Zoo Plzen - 12 species (with another 12 gained but lost species last kept in Plzen)

2. Tierpark Berlin, Twycross Zoo - 5 species

With the top-10 being completed by:

4. Zoo Antwerp, Zoo Berlin, Marwell Zoo, Poznan Nowe Zoo & Port Lympne Wild Animal Park - 3 species

9. Burgers’ Zoo, Zoo Cologne, Zoo Duisburg, Howletts Wild Animal Park, Zoo Krefeld, Zoo Prague, Diergaarde Blijdorp, Zoo Tallinn, Thrigby Hall & Zoo Usti - 2 species

This leaves 50 zoos which were 1 species was kept last before it disappeared.

This list of zoos is much more a mix of the zoos which have a name for rarities now with zoos that used to hold the most diverse collections or ones filled with rarities. Many of the zoos in this list have had a large net loss in terms of species.

@gentle lemur Twycross zoo functioned as a retirement home for multiple very rare primate species this century, including Europe's final Phayre's langur

When looking at years when these species (approximately) appeared or disappeared it is clear that there are less new species appearing in recent years, but also less species disappearing than in recent years:

Year........# gains...........# losses
2000............5......................8
2001............5......................9
2002............6......................5
2003............5......................3
2004............5......................2
2005............5......................5
2006............4......................7
2007............2......................5
2008............14....................2
2009............7......................7

---------------------------------------

2010............7......................8
2011............7......................4
2012............5......................3
2013............3......................2
2014............0......................4
2015............0......................4
2016............1......................2
2017............3......................3
2018............6......................3
2019............5......................2

----------------------------------------

2020............0......................5
2021............5......................2
2022............1......................2
2023............2......................1

For the period of 2000-2009 there were 58 species gained and 53 lost, whereas for the period 2014-2023 23 species were gained and 28 were lost. It is too easy to say that this means we will inadvertently see a decline in the net number of species, as if one would look for the period of 2016-2023 there would be a net gain of 3 species.

@Daubentoniidae Of all the Todd Dalton imports the smooth-coated otters have been among the biggest success stories
What is apparent from this data though is that in the first part of the century many dead end species were lost, which were set to disappear anyway. This includes many remnants from the days zoos could just import anything without caring whether they could really breed them like Commerson’s dolphin and bald red uakari. The first decade also saw the rise of Zoo Plzen as a place for mammal rarities and was the peak time for Todd Dalton importing numerous species via his RSCC. With those drivers on the gaining and losing site diminished in recent years, there is much more relative stability. In 2023 only zoos in Baden-Wurttemberg actually gained new species with new bats for Zoo Karlsruhe and quokka for the Wilhelma. In the next and final mammal post I will try to look ahead to what might be happening in the future based on what we know from the 1990s and the 21st century.

If you think this post was rather short and lacking more in depth analysis, I am sorry, but I have been rather busy lately and I want to get the mammals finished as soon as possible.

@evilmonkey239 Groundhogs are notorious for making predictions, but can they predict their own future in Europe?

 

[Jurek7]

It is interesting, and also worrying, how few zoos and people genuinely work in Europe to bring new species!

As @Haliaeetus mentioned when working together with foreign zoos, large numbers can be imported. Yellow-footed rock wallaby are a good example with multiple zoos importing at least 16 of them from the US this century.

Yes, but a species with a large zoo population on another continent is usually not as valuable for conservation - although of course, always nice to see!

 

[Batto]

how few zoos and people genuinely work in Europe to bring new species!

Is that part of their job description?

 

[HOMIN96]

Is that part of their job description?

In the eyes of average zoochatter, yes it is

 

[DDcorvus]

It will be interesting to see if the role of Todd Dalton and Plzen (although it was as well a dedicated person there who drove that process) will be picked up the coming decade. They had the interesting combination of determination/passion and resources to bring species in which has been proven rare. People that might be interested in this might not have the knowledge, network, finances to bring in a greater number of species, but those institutions that would have that other are not having the interest (or it is more difficult for an individual to push for this due to internal processes). So you need a particular person on a particular place to have this role, which makes it uncertain if they can be replaced.

This is of course a separate discussion of the fact if we want to see this to continue?

 

[Batto]

In the eyes of average zoochatter, yes it is

If only they supported the additional work and expenses financially...

 

[Jurek7]

One of these few remarkable people interested in bringing new animals - and not just any but threatened species - is Radosław Ratajszczak. He worked at Poznan zoo, then became the director of Wrocław zoo (the time of building the Afrykarium) and then retired and leads the Cuc Phuong primate center in Vietnam.

He worked in a team, naturally. But if I understand well, long ago he was the driving force in the import of Bawean deer and Leadbeater's possums to Poznan, then the unsuccessful import of Javan warty pigs, then the import of Visayan warty pigs. Wrocław also kept the Balabac chevrotains in quarantine for Tim Dalton, and kept one pair in barter. Mr Ratajszczak also did a good work in the field - among others rediscoveries and first surveys of rare langurs in Vietnam.

 

[lintworm]

What's next?

For most Zoochatters, it was an unexpected fact that between 2000 and 2023 the number of mammal species kept in Europe has been stable. My preliminary analyses indicate that even between 1990 and 2023 there hasn’t been a sizable net change. Zoochatters tend to be pessimistic about the future of rarities in zoos, but the present and (recent) past should give some cause for optimism, right?

Zoos are ever evolving and we still learn more about mammal husbandry every day. What was good 10 years ago might not be acceptable anymore 10 years from now. The leaps in husbandry that even some of the most popular mammals like elephants and rhinoceroses have undergone in the past decades are staggering. They have led to increased welfare and breeding results unimaginable in the 1990s. That alone should be enough to say that truly predicting the future is impossible, but it is an interesting pastime. What is clear is that there has been a trend towards larger (and better structured) enclosures for decades and I don’t see any indication this will suddenly stop. Until now this has not led to a net decrease in available “holding slots'' for mammals. As many new zoos emerged or have expanded in size this century. While some places like the Netherlands now seem saturated for zoos, there is still plenty of room for improvement in countries with less of a zoo culture like in France or Southern Europe. Excluding wild parks a conservative guesstimate of how many holding slots there are in Europe for mammals ranges around 25.000. Which would mean that if every species was kept in the same amount of zoos, there would be 40 holders per mammal species. This means space per se will likely not be the determining factor, but I am aware that there are plenty of reasons why some species are kept more often than others.

@Animal Advances in rhino husbandry show how much can change in a short amount of time

There is however an increasing trend towards endangered species, preferably ones that are EEP managed. This together with a hunch that zoos increasingly chose the same “cute” species to draw in crowds could be seen as indication we are in for a decline in mammal species richness in the coming decades. I do personally think that is an oversimplification, especially for mammals. Diversity has always been driven by a limited number of zoos and as long as they “resist” to make the same collection choices as the masses, the numbers don’t need to change. I assume that there is a trade-off between making rules top-down and how many zoos adhere to them. If EAZA gets too strict, I would guess there will be more EAZA zoos that will follow their own course and keep non-recommended species. Apart from EAZA zoos there are numerous non-EAZA zoos with an appetite for rarities. These either are happy to import new species, like Hamerton, or are increasingly a refuge for species that have a hard time in EAZA, like Tierpark Germendorf-Oranienburg. It is not unlikely the role for such non-EAZA zoos will grow when it comes to managing rare species. The upside from being EEP-managed is that even rare species have a high chance of remaining in Europe. Compared to 2000 there are probably less species at high risk of extinction, as can be seen by the large numbers who are increasing in popularity, many having been extremely rare at the start of the century (white-lipped deer and Francois’ langur are examples).

@hmb_zoo Though possibly not in time for these lesser spot-nosed guenon, non-EAZA zoos have the potential to maintain large number of species "unwanted" in EAZA zoos

When looking at the numbers the outlook now is not all that different from 2000. There is a similar number of dead end species and for the coming 23 years my estimate is that we will lose some 80-140 species (dead end species and more), so on average 3.5-6 per year, that is around the same number lost the past 23 years (103 species lost since 2000, excluding gained-but lost species). While Zoochatters seem to hate the loss of species, it is a given that it happens regularly given how many species are only around in low numbers. The question is not how many species will be lost, but how many new species will appear in the future to compensate for that loss. That is something that really cannot be predicted with high accuracy. It will likely come down to how many zoos/individuals that think it is worth the effort. Once a species has been imported, there are often plenty of zoos willing to take on offspring if the species is successful (Palawan porcupine and black-and-rufous sengi are but 2 examples). So it is not that zoos don’t have an appetite for new species, but rather that they lack the appetite for the immense workload necessary for an intercontinental import (the workload is lower if you source new species that are already around in the private trade or kept in research institutions in Europe). Based on the past 8-10 years an average gain of 2-3 new species per year seems a reasonable lower benchmark. For 23 years that would amount to 46-69 new species. So if very few zoos are willing to go the extra mile it seems a net loss of 10-95 species is realistic. That would amount to a 2%-15% decline over a period of 23 years. But if the appetite for new species is higher in a few zoos, that would probably easily shift to a range of 5% decline to 5% growth. All in all I personally think it is most likely we will see a slight decline (somewhere around 5%) in the number of mammal species kept for the coming 23 years, but I wouldn’t bet any money on it.

@hmb_zoo Importing new species from other continents is a lot of work, but if you can get them to breed, other zoos are often easily interested as the rise of the rufous bettong shows

It is easy to see where future losses will be: it is a given we will see a net loss of primates and ungulates in the coming decades and a fair number of currently kept rodents will be gone from Europe too in the future. It is however much harder to predict which species will be gained. I personally think we will see a further gain in Australasian species, I think it is likely either long-beaked echidna and/or platypus will be on show in Europe within a decade. I also expect more small endangered European mammals getting captive breeding programs. This would include the likes of Pyrenean desman and Romanian hamster (and hopefully renewed attention for marbled polecat), but also locally endangered/endemic species like Dutch tundra vole (an endemic subspecies that is endangered). There is also an opportunity that intercontinental animal exchanges will become more common with zoos in Asia, Africa and the Americas becoming ever more professional. This has the possibility that more international breeding programs will be established or endangered species being transferred to other continents for educational purposes. The import of Brazilian mergansers by Prague last year is an example and there is ample opportunity that the same will happen with mammals. Especially smaller mammals, including carnivores and primates, would likely profit from that.

@Najade I think it is a reasonable guess that long-beaked echidna will find their way to Europe again in the near future

But with the future being the future, the outcome could well be different. What is certain is that we should count ourselves lucky to have such a diverse cast of zoo mammals on the continent with plenty of exciting additions this century to compensate for the losses. That mammal diversity has remained stable at a continental level, while enclosures have become so much better, is a big win for me personally. It also gives me hope that there won’t be a sudden breakdown in diversity with all zoos following the old Dublin route of focusing nearly exclusively on crowd-pleasers.

With that we have come to the end of the first part of this thread (after close to 70.000 words), I hope you enjoyed it and stay tuned for the birds after a long break!

 

[Lafone]

Excellent thread. Interesting and I certainly learned a few things reading it!

 

[remar]

Well, i guess there is one thing left to do

A big thank you @lintworm for sharing this amazing masterpiece with us!

 

[JVM]

This thread was a wonderful read and as an American who until recently was almost completely ignorant about European collections and is still only just taking my first steps into a larger world, deeply educational. The contrasts between the EAZA and AZA are very fascinating but I've also really appreciated the historical notes and looking at the how and why certain species are rising and disappearing - whether it be related to lifespans, rates of reproductions, or demeanor. A huge thanks to @lintworm for the incredible effort it probably took to compile all of this valuable data, analyze it and organize these posts, and warm appreciation to all of the zoochatters who added their own knowledge.

I definitely think one of the more understated factors in this thread is that it sounds like decent new facilities have opened more frequently in Europe than in the United States. New collections mean more spaces for both existing and new species balances losses of both at other institutions; whereas we haven't had a single new terrestrial collection in over two decades, and therefore space is sadly much more competitive. It also sounds like Europe might have more focused and specialist collections compared to here, not that they are absent here.

 

[Brayden Delashmutt]

Also, which wolf subspecies are EEP managed?

 

[PossumRoach]

Also, which wolf subspecies are EEP managed?

There’s an EEP program for non specific grey wolves and another Iberian wolves.

 

[lintworm]

And then on to birds....

Well, I promised you all there would be a lot of similar posts about birdy trends in this thread at some point this year. Unfortunately for you, life has caught up with me and due to a combination of factors , I have a lot less time & energy to write and analyze for fun this year. This means it is unlikely there will ever be a continuation in as much details for our feathered friends. But as it has taken me quite a lot of time put together the bird dataset last year, it would be a waste not to write at least a tiny little bit.

So the summary is as follows (based on data up to June 2023): in the period 2000-2023 a total of 2240 bird species were kept in European zoos according to Zootierliste, that is roughly 2.5x the number mammal species kept in the same time period (which stands at 880).

@Rhino00 The exciting addition of the Brazilian merganser to the European zoo world happened after June 2023, as did the death of Europe's last dwarf cassowary, so these changes aren't included in the numbers

Of those 2240 species 1656-1727 species were most likely present in 2000, and 1499-1510 species were most likely present in 2023, so a decline of 157-228 species. That means there has been roughly a 8.8%-13.2% (mean 11%) decline in the number of bird species kept in those 23 years. The median zoochat expectation was a 13% decline, so not that far off, but likely slightly too pessimistic. This decline can in large part be attributed to a decline in the number of passerines kept, whose number of species kept declined by almost 25% from 536-574 to 409-416. For non-passerines there was only a slight decline from 1119-1152 to 1090-1094 species, so 2%-5.4%. A large number of passerine species was also kept at some point between 2000 and 2023, but not at the start of the century or end of the sampling period, that concerned some 227 species. For non-passerines, only 85 species were present at some point this century but not in 2000 or 2023.

There are a few reasons for the decline and the high volatility of bird holdings. Most important to note is that the majority of bird species kept this century was never very common in captivity, and often incredibly rare, limited to 1-3 holders this century. Small populations are per definition at a high risk of extinction and in many cases that did happen. Especially with passerines there are few rarities that remain rarely kept for a long time without disappearing. Only the few zoos that don't treat these rare birds as expendables and set up a breeding regime (often exchanging animals with private keepers), are able to keep rare passerines for decades. Burgers' Zoo is probably the prime example of this, having good success and often larger numbers of their rare species. Compare this with zoos like Plzen and Walsrode whose rarities often appear and disappear at high pace because they were often only kept in very small numbers. Both Plzen and Walsrode of-course also have their success stories but the number of species they go through is quite staggering if you add it all up and breeding success much more limited when you keep only small numbers of a species.

@Therabu Burgers' Zoo has multiple breeding pairs of painted bunting and breeds up to two dozen of them per year. Such numbers are needed to keep such small fragile species long term

An important reason for the decline is also the ban on imports of wild birds into the EU that came into effect in 2005. Before that is was very common to see new bird species being imported and being kept in a single/a few zoos for a short period, before disappearing again. With the ban in effect, a sizable number of new species consists of confiscated animals, which in most cases also means they die out within a few years. But the number of species entering zoos is smaller than before. A ban on wild imports also meant zoos couldn't treat birds as expandable items as much as they used to, because there is no infinite supply anymore. There are still far more bird species in private hands than in zoos and many zoos with large bird collections frequently exchange birds with private keepers. But an important source has been gone for nearly 20 years now and especially with passerines this shows.

It is also important to note that bird diversity has throughout the century been driven by some bird parks and 20-30 large zoos. This century has seen the closure of several bird parks (which haven't really been replaced elsewhere), but also the significant decline in the number of bird species kept in some zoos. Both Berlins have seen huge declines (roughly 50%) in species numbers as an example, but many other zoos too. This is not uniform, a zoo like Cologne (but also Plzen) has actually seen their bird collection grow this century. But if diversity is driven by a few places, the closure of a single random bird park can mean the loss of multiple species simultaneously. Imagine if Loro Parque would close, that would mean the loss of dozens of species at once. That is something that wouldn't really happen with mammals. This reliance on a few zoos has made bird species numbers far more susceptible to changes than e.g. mammals.

@lintworm Bird houses like the new one in Berlin are increasingly rare, whereas large aviaries become the norm

Whereas mammal holdings remained stable because losses in big zoos were counterweighted by the rise of smaller zoos and zoos in e.g. France, this hasn't hasn't happened with birds. There have nevertheless been some winners when it comes to birds. An obvious one are the herons & ibisses, but also birds-of-paradise are now more popular. In general there seems to be a trend towards "fancy" species and species that do well in large (walk-through) aviaries. It also helps tremendously if you get yourself an EEP. From scaly-sided merganser and white-winged wood duck to Sumatran laughing-thrush and green cardinal. Birds with an EEP are ones that gain new holders the fastest. Many zoos hold less bird species than mammals, but as there are far more birds to chose from, a criterion like EEP status becomes important at once.

This is a very short summary of what could have been 100 separate posts, but it was not meant to be.