An Analysis of Animals in Speculative Zoos in the United State

MOG2012

Well-Known Member
As I've hit a writers block for the New England thread and a lack of interest in the planet zoo thread, I'm going to pause on working them and instead focus on my Las Vegas spec zoo. However, I wanted to go in a big research phase so this thread, I will be analysing all of the mammals in American captivity and how they can be in spec zoos. I will start my first post in a couple days with monotremes being first.

Abundance Scale:
Abundant: 51+
Extremely Common: 36-50
Common: 21-35
Uncommon: 11-20
Rare: 6-10
Extremely Rare: 1-5

Feasibility Scale:
Extremely Plausible: 5
Plausible: 4
Somewhat Plausible: 3
Barely Plausible: 2
Implausible: 1

I will also include exhibit design considerations, captivity metrics, some general information, and educational/visitor appeal information for each species.
 
what will be your main sources of how many are in various zoos?
will this be all known specimens in accredited and unaccredited zoos?
sounds like a lot of work, good luck but it will be very interesting
 
what will be your main sources of how many are in various zoos?
will this be all known specimens in accredited and unaccredited zoos?
sounds like a lot of work, good luck but it will be very interesting
I’m going to do every known specimen held in captivity in the United States in the last decade including in the pet trade (also phase in and phase out species) with some spec zoo help such as enclosure, group sizes, exhibit types, compatible species, etc. I’m going to use a various sources online such as the zoos’ websites, AZA information, zootierliste, zoo chat, etc.
 
I’m going to do every known specimen held in captivity in the United States in the last decade including in the pet trade (also phase in and phase out species) with some spec zoo help such as enclosure, group sizes, exhibit types, compatible species, etc. I’m going to use a various sources online such as the zoos’ websites, AZA information, zootierliste, zoo chat, etc.
Fair warning. The websites of some zoos may not be entirely accurate. In most cases, I see even some notable species held off the website, as well as smaller species.
 
Order Monotremata
5 species across 2 families
2 species kept currently (40%)

This order is the only known family of mammals to lay eggs.

Echidnas - Family Tachyglossidae (4 species)

Short-beaked Echidna - Tachyglossus aculeatus
There are 5 subspecies of this species; Eastern Short-beaked Echidna (T. a. aculeatus), Kangaroo Island Echidna (T. a. multiaculeatus), New Guinea Short-beaked Echidna (T. a. lawesii), Tasmanian Echidna (T. a. setosus), and Western Short-beaked Echidna (T. a. acanthion). Out of these 5 subspecies, only Western Short-beaked Echidnas aren't currently found in American captivity, being only found in Australian captivity. This is also the only species of echidna found in American captivity.

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Image Credit to @Coelacanth18 at Los Angeles Zoo
AZA Abundance: Rare
Non-AZA Abundance: Extremely Rare
Overall Abundance: Uncommon​
The two unaccredited zoos that have echidnas are the Ellen Trout Zoo and TGR Exotics Wildlife Park with Ellen Trout Zoo obtaining their echidnas when they were an AZA member and TGR Exotics obtaining them from the pet trade from West Papua. These echidnas are present in the exotic and illegal pet trade of the US but are uncommon.
Generic Species: Uncommon
Nominate Subspecies Overall Abundance: Extremely Rare
Kangaroo Island Subspecies Overall Abundance: Extremely Rare
New Guinea Subspecies Overall Abundance: Extremely Rare
Tasmanian Subspecies Overall Abundance: Extremely Rare​
The Short-Beaked Echidna is found in Australia and New Guinea including some islands of the Australian coast. The New Guinea and Western subspecies are common in tropical climates and the Kangaroo Island, nominate and Tasmanian subspecies are found in temperate climates with the nominate subspecies also being found in arid climates.

While these echidnas can live for more than a decade in captivity, they're difficult to breed in captivity with improved breeding success recently. They are solitary species, often only being housed alone or in small groups of 2-3 individuals. During the breeding season, a group of up to 10 males may follow a female for mating opportunities.

Some possible exhibits with this species could be a generic Australian one, a New Guinea exhibit, Australian desert, Australian Rainforest, etc. with this species being found in every region of Continental Australia. In zoos, this species is sometimes held in mixed species enclosures with the following being compatible species based on different mixes in zoos (and theoretical mixes) though echidnas are often seldomly seen due to their seclusive, burrowing and nocturnal behaviors. Red lights are somewhat commonly used in enclosures for this species as it "replicates" their natural period of activeness as accurate as possible for visitor viewing.

Terrestrial Vertebrates: Huon Tree Kangaroo (Dendrolagus matschiei), Tammar Wallaby (Notamacropus eugenii), Southern Hairy-Nosed Wombat (Lasiorhinus latifrons)
Arboreal Vertebrates: Boyd's Forest Dragon (Lophosaurus boydii), Koala (Phascolarctos cinereus), Laughing Kookaburra (Dacelo novaeguineae), Princess Parrot (Polytelis alexandrae), Tawny Frogmouth (Podargus strigoides)

If you have male echidnas, the birds wouldn't be compatible. In general, it would be best if the echidnas have a seperated enclosure so they won't be disturbed. If it wasn't obvious, not all of these species are compatible together but individually as a species, each are compatible.

Overall Feasibility for Spec Zoo Usage: Somewhat Plausible as these are present in the pet trade but are hard to breed. This species would serve as a representation of one of the three major groups of mammals (monotremes) and could be used as an animal ambassador (it would be shy though). In popular culture, the echidna is less featured than the platypus though it has been featured recently as Knuckles in the Sonic the Hedgehog franchise.

Other Echidna species (Genus Zaglossus)
These 3 species are only found in Australian captivity due to having highly specialized dietary needs (insects, earthworms, etc.)
Overall Feasibility for Spec Zoo Usage: Implausible

Platypus - Family Ornithorhynchidae (1 species)
Platypus - Ornithorhynchus anatinus
Despite being well known, the Platypus is rare in captivity, only being found in 1 zoo outside of Australia. Until 2019, most of the world had no platypuses since 1957 but then Taronga Zoo loaned two individuals to serve as ambassadors.

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Image Credit to @WhistlingKite24 with a wild platypus as there are little to none photos I could find that clearly show the individuals in Escondido.

AZA Abundance: Extremely Rare
Non-AZA Abundance: Not Present
Overall Abundance: Extremely Rare​

The Platypus is found in waterways in Eastern Australia, including Tasmania. The platypus is monotypic and is the sole species in its family. It is found in temperate climates though it's commonly housed indoors.

Platypus typically live up to 20 years in captivity which is around 5 years more than their wild lifespan. Like the echidnas, these species are hard to breed in captivity with the first breeding happening a little over a century after the first platypus in captivity. These creatures are solitary except during the breeding season with 2-3 individuals being housed in the same enclosure in captivity.

Some possible exhibits with this species could be a generic Australian one, an Australian freshwater exhibit, and an Eastern Australia exhibit. In zoos, this species is never held in mixed species enclosures due to being easily stressed with noise and vibrations often leading to illness and death.

Overall Feasibility for Spec Zoo Usage: Implausible as it took over 60 years for platypus to be outside of Australia, due to the strict exportation laws, costly enclosure needs, and highly specialized diets (live yabbies which are illegal in some states).

Progress
1/106 families
2 species currently present


What do you think so far? Please identify any mistakes, errors, feedback, etc.
 
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Already, your take on the feasibility of monotremes is really well-executed, and dare I say, this might be your most put-together thread you’ve made thus far!

Conceptually, this is a thread I have been looking forward to, and I hope you have further plans to carry on this thread as far as it can go; keep it up @MOG2012 !

By the way, here’s to having a new follower ;)
 
While I agree that they aren't a species that's likely to be seen much in zoos in the future, I wouldn't necessarily say that platypus are an implausible acquisition. The fact that there was a 60 year gap between American displays of the species doesn't mean it would take 60 years to get new ones - for most of those 60 years, no one was trying to get platypus, in large part because their husbandry was considered such a daunting challenge for American zoos (there were a few facilities that toyed with the idea - Omaha, National Aquarium, etc - with varying degrees of seriousness). Especially now that there's an American facility which has successfully kept the species for years, I'd say it's all the more plausible that future imports could be made. Nothing that would make the species common, per se, but I could potentially envision a future where platypus are about as common in the US as giant panda.
 
Due to @Aardwolf 's helpful post, Platypus will be changed to Barely Plausible.

I also saw that I made the mistake of marking the Huon Tree Kangaroo as terrestrial when it's mostly arboreal.

Order Didelphimorphia: Part 1
126 species across 1 families
6 species kept currently (4.76%)


Opossums - Family Didelphidae (126 species)

Virginia Opossum - Didelphis virginiana
There are 3 subspecies of Virginia Opossum; Eastern Virginia Opossum (D. virginiana virgianana), North Mexican Virginia Opossum (D. v. California), and Yucatan Virginia Opossum (D. v. yucatenensis). This opossum is the only marsupial native to the United States and is also the northernmost found marsupial in the world.
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Image Credit to @RatioTile at Woodland Park Zoo


AZA Abundance: Abundant
Non-AZA Abundance: Abundant
Overall Abundance: Abundant

As a native species of the United States, most individuals in captivity are rescues with most of the zoos that having them in their native range. In zoos, this species is commonly used as an animal ambassador due to their docile and somewhat cute appearance.

The Virginia Opossum is found as South as northern Costa Rica to as north as southern Canada. This opossum is vary adaptable, being found in many different climates. For the nomination subspecies, it's found in mostly temperate climates though with the population in Florida, it could be also said to live in tropical climates. The North Mexican subspecies is found in mostly arid climates with some temperate climates and the Yucatan subspecies is found in tropical climates. In captivity, the housing can be both indoors and outdoors as the opossum is extremely adaptable.

Virginia Opossums are profilic breeders though they only live 2-4 years in captivity and likely lower due them being mostly rescues. They are solitary species, often only being housed alone or in family groups (a mother with pouch young) . During the breeding season, they are sometimes housed in pairs.

Some possible exhibits with this species could be a City life exhibit, native animal exhibit, North american exhibit, nocturnal house, forest exhibit, childen's zoo, etc.. In zoos, this species is sometimes held in mixed species enclosures with other native/rescue animals. They are arboreal so there is always some "tree-like or branch" object in the enclosure.

Terrestrial Vertebrates: Striped Skunk (Mephitis mephitis)
Arboreal Vertebrates: Great Horned Owl (Bubo virginianus), North American Porcupine (Erethizon dorsatum)
Both Terrestial and Arboreal Vertebrates: Common Raccoon (Procyon lotor)

Skunks are the most common animal for mixed species with these opossums. If there are opossum joeys, there shouldn't be owls or raccoons. If it wasn't obvious, not all of these species are compatible together but individually as a species, each are compatible.

Overall Feasibility for Spec Zoo Usage: Extremely Plausible for zoos in it's native range as they are common to see as rescues but if the zoo is not in the native range, then it is Plausible as there are sometimes joeys in zoos, and they are still found in most of the United States.

Grey Short-Tailed Opossum - Monodelphis domestica
This species is monotypic being one of the only marsupials without a pouch. Grey short-tailed opossums are commonly found in the exotic pet trade with them also being used as research models in science (hence their nickname as "the laboratory opossum")
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Image Credit to @Alwaysevergreen in the United Kingdom as there isn't any photos of it in the United States

AZA Abundance: Not Present
Non-AZA Abundance: Extremely Rare
Overall Abundance: Extremely Rare

As a species with no conservation value, this opossum isn't found in any AZA facilities with it only being found in around 5 non AZA-accredited facilities in the US, likely obtained via the exotic pet trade.

The Grey Short-Tailed Opossum is found South of the Amazon River in Bolivia, Brazil, Paraguay, and Argentina. This opossum was the first marsupial to have it's genome sequenced. In captivity, it's housed indoors due to them being from tropical climates with their need for a high humidity

Grey Short-Tailed Opossums are also easy breeders with a similar lifespan in captivity of 3-5 years. They are solitary species, often only being housed alone due to them being aggressive even during breeding season

Some possible exhibits with this species could be a South American exhibit, tropical savanna exhibit, nocturnal house, animals in research exhibit, Children's Zoom etc. In zoos, this species isn't housed in mixed species exhibits due to them being semi-aggresive

Overall Feasibility for Spec Zoo Usage: Somewhat Plausible as they are present in the United States (non-accredited zoos, research facilities, and exotic pet trade) but they aren't present in AZA facilities. There isn't really a need for them to be exhibited due to their prevalence in the wild

Derby's Woolly Opossum - Caluromys derbianus
This species has 7 recognized subspecies though there isn't really any common names for them yet and there hasn't been a taxonomic study for them in American captivity.
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Image Credit to @RatioTile at Stamford Museum & Nature Center

AZA Abundance: Not Present
Non-AZA Abundance: Extremely Rare
Overall Abundance: Extremely Rare

Despite being common in European collections, Derby's woolly opossums are absent in AZA captivity due to a lack of interest and conservation needs. This species is relatively common in the pet trade which is likely the source of the 5 holders in the US.

Derby's Woolly Opossum is found in Central America from western Ecuador and Colombia to southern Mexico. This opossum is the largest in it's genus though only weighs 200-400 grams. In captivity, it's housed indoors due to their sensitivity to temperature fluctuations

Unlike most opossums, Derby's woolly opossums are less commonly bred though there has been succesfull breeding. They also have a longer lifespan than most opossums, surviving 5-8 years there. They are solitary species, though during breeding season, they can be housed in pairs.

Some possible exhibits with this species could be a nocturnal house, Central American exhibit, rainforest house, small mammal house, etc. In zoos, this species isn't housed in mixed species exhibits due to them being semi-aggresive

Overall Feasibility for Spec Zoo Usage: Somewhat Plausible as they are present in non-accredited American zoos but they aren't present in AZA facilities because there is a lack of interest.

Grey Four-Eyed Opossum - Philander opossum species complex
This species recently split up into P. canus, P. melanurus, P. opossum and P. vossi so I have no idea which species is in the United States.
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Image Credit to @RatioTile with a Guianan Four-Eyed Opossum in an American pet store.

AZA Abundance: Not Present
Non-AZA Abundance: Extremely Rare
Overall Abundance: Extremely Rare

As a species with no conservation value, this opossum isn't found in any AZA facilities with it only being found in 1 non AZA-accredited facilities in the US, Safari Tails Adventures which is in Mississippi. Despite being nearly absent in zoos, there is an established population in the pet trade via imports from mostly Guyana.

The Grey Four-Eyed Opossum species complex is found Guyana, Suriname, French Guiana, and northern Brazil. In captivity, it's housed indoors due to them being from tropical climates due to them being sensitive to the cold.

Grey Four-Eyed Opossums are also not hard to breed in captivity but isn't exactly easy due to their sensitivity with the environment. Like a lot of opossums, they have a lifespan in captivity of 3-5 years. They are solitary species, though they can be housed in pairs during breeding season or as a mother with her pouch young.

Some possible exhibits with this species could be a nocturnal house, tropical rainforest house, small mammal house, South America exhibit, etc. In zoos, this species isn't housed in mixed species exhibits due to them being semi-aggresive

Overall Feasibility for Spec Zoo Usage: Barely Plausible as they are present in the United States (a non-accredited zoo, and exotic pet trade) but grey four-eyed opossums don't have a breeding population in the US with a reliance on wild obtained individuals. They are also on the Phase Out list for the AZA RCP Marsupial and Monotreme TAG as of 2012 so it's unlikely that an AZA zoo will obtain them.

I'll continue later this week with the last two opossum species found in American captivity and the remaining species of opossum.
 
A great thread that helps me plan my speculative zoos without having to visit multiple “______” populations in North America threads here on ZooChat, exotic pet classifieds, and general availability searches on Google, Zooinstitutes, and the like. Your work is appreciated.
 
Technically correct, in the same sense that it would be entirely accurate to say that there are more than four species of fish. :D:p
The numbers I found online weren't really similar some ranged from 9 to 27 so I decided to make it true at all times (though more vague)
 
An interesting thread, though a few notes.

Out of these 5 subspecies, only Western Short-beaked Echidnas aren't currently found in American captivity

While I know where you got this information, it's worth noting it's not 100% clear whether the subspecies are as claimed.

While these echidnas can live for more than a decade in captivity

As has been noted already, a decade is below average for echidnas - thirty to forty years is common, and it's not uncommon for animals to reach their 50's. The oldest documented echidna in the US was almost 60.

If you have male echidnas, the birds wouldn't be compatible.
Arboreal Vertebrates: Great Horned Owl (Bubo virginianus)

If you're going to suggest mixed species exhibits, might want to err on the side of caution. Why exactly are male echidnas incompatible with birds? I've heard nothing re this before. Also I would strongly discourage housing opossums with Great Horned Owl, given it is well documented that these owls predate even adult opossums...
 
As has been noted already, a decade is below average for echidnas - thirty to forty years is common, and it's not uncommon for animals to reach their 50's. The oldest documented echidna in the US was almost 60..
The Brookfield Zoo currently has three short-beaked echidnas who are 50+, one female who will soon turn 56 (the current oldest echidna in the US), and a breeding pair aged 50 and 51 years old who had puggles together in 2022 (aged 47 and 48 years old) and 2024 (49 and 50), so this goes to show that 50 is certainly a reachable age, let alone still in the breeding age range!
 
one female who will soon turn 56 (the current oldest echidna in the US)

If he is still alive, Omaha's male is similar aged.

so this goes to show that 50 is certainly a reachable age

In addition to Omaha as I just mentioned, assuming they're still alive animals at Toledo and The Living Desert are also running in their 50's. Then of course there's JR the Long-beak at Taronga who should hit 60 this coming year I believe.
 
The Brookfield Zoo currently has three short-beaked echidnas who are 50+, one female who will soon turn 56 (the current oldest echidna in the US), and a breeding pair aged 50 and 51 years old who had puggles together in 2022 (aged 47 and 48 years old) and 2024 (49 and 50), so this goes to show that 50 is certainly a reachable age, let alone still in the breeding age range!
I’m fairly sure the individual at Toronto is around 40-41 years old. Not as old as the individuals you mentioned but definitely older than the range @MOG2012 initially presented. Which is cool to know as I was unaware that echidnas had such a lengthy lifespan until now.
 
If he is still alive, Omaha's male is similar aged.
Omaha's male echidna, Casper, was born in 1971, and would thus be two years younger than Adelaide (Brookfield's 56-year-old female).
Then of course there's JR the Long-beak at Taronga who should hit 60 this coming year I believe.
JR's age is unknown, but he is believed to be born around 1968. He once lived at the Dallas Zoo, where he was named Pinocchio, before he moved to the London Zoo, then later Taronga Zoo, where he remains now.
 
Source being? That doesn't match the AZA docs.
Source for Casper's age: - it may be a little outdated article, but it does state he was brought to the San Diego Zoo in 1971 when he was quite young and he was an estimated 42 years old as of 2013.
Casper the echidna is the first of his kind at Omaha's zoo
Source for Adelaide's age:
x.com
Somewhere around then yes, I might be mixing up the dates on that one.
As for JR's age, I found this information described by a senior keeper at Taronga Zoo to @Casuarius_casuarius in this photo.
‘JR’ the Eastern Long-Beaked Echidna (Zaglossus bartoni) - ZooChat
 
Source for Casper's age: - it may be a little outdated article, but it does state he was brought to the San Diego Zoo in 1971 when he was quite young and he was an estimated 42 years old as of 2013.
Casper the echidna is the first of his kind at Omaha's zoo
Source for Adelaide's age:
x.com

Hmm - studbook records pin them both as believed born in 1970. They are both wild caught so assumptions are made either way. Adelaide's 'birthday' matches the date she arrived in the US, not necessarily her real birthday. There's no listing for San Diego on Casper's transfer record either, who knows there. Either way, both are assumed to be approximately the same age and in theory are both 55 this year.
 
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