So while I was just browsing the internet I found this study about hunting success in dragonflies. The spangled skimmer dragonflies (Libellula cyanea) were wild-caught but then housed in a large greenhouse-style enclosure with dimensions of 7.3×7.3×4.6 metres for the duration of the study. The greenhouse contained shrubbery and artificial ponds (as well as camera banks for photographing the insects hunting) and was enclosed by wide mesh screening that allowed natural light, air currents and small prey to enter the enclosure. This natural small prey was supplemented with fruit flies that were released and encouraged to stay in the enclosure with piles of rotting fruit. However, I couldn't see any information regarding how many dragonflies were in the enclosure at one time. The study, which includes an image of the enclosure, is included below: Linking biomechanics and ecology through predator–prey interactions: flight performance of dragonflies and their prey
While I was doing research for an MSc assignment, I found this rather interesting information from last year - the organisation ADEFFA at their centre in Camadoca (Catalonia) have managed to successfully rear a number of splendid cruisers Macromia splendens to emergence; one translation I found mentions five larvae being maintained and three adults metamorphosing. This dragonfly is listed as Vulnerable on the IUCN Red List and its keeping is part of an ex-situ breeding project that also includes the Pyrenean desman. The translated link mentioning the number of dragonflies is included here: Google Translate This translated Twitter link has pictures of the larvae and adults of the dragonflies: Google Translate
Just looking at the main page for ADEFFA, it seems like the Camadoca Centre is open for guided tours of 1.5 to 2 hours. Google Translate
I have just realised, on looking back at the news about breeding damselflies for the upcoming exhibit at Slimbridge, it also mentions right at the bottom of the article that new trials will begin to rear the nymphs of emperor and hairy dragonflies so that they can also be integrated into the display: Rearing Damselflies - a successful first for WWT Slimbridge! | WWT
A few miles from us, just into Northamptonshire, Dame Miriam Rothschild hosted the National Dragonfly Museum at Ashton Mill, part of her estate near Oundle. https://www.ruarymackenziedodds.co.uk/dragonflies I never visited, and it did not stay open for very long. A 16pp guide-book was produced by Anglian Water in 1985. I don't know if it had live specimens along with the mounted ones...
It's an old forum, but I know the facilities involved in this topic, so I'll write this down. This image source is Upo Dragonfly Country's homepage. "Upo Dragonfly Country"(Upo Jamjari Nara/우포잠자리나라) in Changnyeong county, South Korea, is a facility built to display live dragonflies. not only larvae but also adult dragonflies are displayed in huge glass greenhouse, but the size of the greenhouse is so large. So I think few people have seen adult dragonflies detail. In this video, you can see the figure of Upo dragonfly country. The Dragonfly Exhibition Center starts at about 4 minutes and 40 seconds. there are no adult dragonflies, but you can see the announcer feeding mosquito larvae to dragonfly larvae from 6 minutes of this video. Although it is the only place where living dragonflies are displayed at all times in Korea, I don't like their operation method. They are engaged in experience activities such as catching live guppies, and touching frogs in several hidden boxes to find out which boxes the frogs are in, and I don't think these activities have any educational effect. In addition, they explain that the natural enemies of dragonflies, such as Largemouth bass and Quail on display, are locked up because "the sin of eating dragonflies". I think this explanation not looking good. Although Largemouth bass is an exogenous species that disrupt the ecosystem in Korea, but that explanation can make children, who are the main visitors of here, have biased views on animals.
Here is a link to the article how orangeblack Hawaiian damselfies are reared in captivity for conservation (eggs are collected and larvae reared individually and returned shortly before moulting into adults): 'They're Super Cute': How One Scientist Is Saving Weird Bugs From Extinction
Seems like an incredible place ! Very refreshing to see such an enormous focus on these invertebrates. Interesting, I'll have a read of this later, thanks for sharing !
Saint Louis Zoo has dragonflies zooming around in the Butterfly House attached to the Insectarium. I'm not well-versed in insect taxonomy, so I couldn't tell you what species, but I saw quite a few of them the last time I went to that area. Sadly, the Insectarium is closed right now due to Covid-19, and has been since the zoo reopened; hopefully it will be viewable again sometime in the near future.