i imagine there are probably more ring tails in captivity around the world than in madagascar
Apparently even the ringtailed lemur studbook keepers think that it is in fact a necessity to limit the reproduction of the species in captivity and for zoos to make more room for more threatened lemur species.
Obviously the figures which follow are a decade out-of-date, but as it happens a book released in 2010 (
Lemurs of Madagascar 3rd Edition Mittermeier et al) - gave fairly precise numbers for how many individuals of each lemur species were held in captivity at the time of writing. These provide an interesting insight into just how heavily weighted towards Ring-tailed Lemur captive populations of lemurs are.
It's also interesting to see a number of species now entirely absent from captivity which were still held in 2009, and several others which are on the verge of disappearing:
Microcebus murinus - c.150 individuals worldwide
Microcebus mamirata - 4 individuals in Madagascar
Microcebus rufus - 4 individuals in Madagascar
Microcebus jollyae - 4 individuals in Madagascar
Microcebus lehilahytsara - c.24 individuals in Europe and Madagascar
Microcebus simmonsi - 4 individuals in Madagascar
Microcebus mittermeieri - 4 individuals in Madagascar
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Mirza zaza - 6 individuals in USA and Europe
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Cheirogaleus medius - c.50 individuals in USA and Europe
Cheirogaleus major - 5 individuals in Europe and Madagascar
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Hapalemur griseus griseus - 16 individuals in USA and Europe
Hapalemur griseus gilberti - unstated number of individuals in Madagascar
Hapalemur griseus ranomafanensis - "several" individuals in Madagascar
Hapalemur occidentalis - 18 individuals in Europe
Hapalemur alaotrensis - 66 individuals in Europe
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Prolemur simus - 19 individuals in Europe and Madagascar
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Lemur catta - 2500 individuals in zoos worldwide, and "many more in smaller roadside collections, laboratories, and the pet trade"
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Eulemur fulvus - c.160 individuals worldwide
Eulemur rufus / Eulemur rufifrons - unclear numbers due to taxonomic confusion - both species found in "a number of collections worldwide"
Eulemur albifrons - c.150 individuals worldwide
Eulemur sanfordi - 6 individuals in USA
Eulemur cinereiceps - 12 individuals in Europe
Eulemur collaris - 37 individuals in USA and Europe
Eulemur macaco - c.160 individuals worldwide
Eulemur flavifrons - 75 individuals worldwide
Eulemur coronatus - c.100 individuals worldwide
Eulemur rubriventer - 165 individuals worldwide
Eulemur mongoz - 111 individuals worldwide
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Varecia variegata variegata - c.770 individuals worldwide
Varecia variegata subcincta - 38 individuals in Europe
Varecia rubra - 590 individuals worldwide
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Propithecus coronatus - 19 individuals in Europe and Madagascar
Propithecus coquereli - c.55 individuals in USA and Madagascar
Propithecus diadema - 2 individuals in USA and Madagascar
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Daubentonia madagascariensis - c.50 individuals worldwide
.