The World Health Organisation today publishes a report warning that noise is one of the most hazardous forms of pollution.

Contributing researchers at Queen’s University Belfast point out that noise doesn’t just impact on humans. It also changes behaviour in animals, including amphibians, arthropods, birds, fish, mammals, molluscs, and reptiles — terrestrial or aquatic.

Though unsurprising the idea of noise pollution having a negative impact on animals certainly goes unremarked when compared to our new-found awareness of the toxic impact plastics have when dumped in our oceans.

That awareness is in part because of the decades-long campaigning by conservationist David Attenborough. He has, since 1952, used television to reveal the wonders of our world. He has been a significant, if not the significant, figure is creating today’s awareness around wildlife and our obligations to it.

He, and his camera crew, have brought wildlife spectacle — think of his remarkable hummingbirds footage — into our sitting rooms.

Wildlife and plants have been demystified. It says something profound about us that despite this pointing out, this powerful evangelism, the world’s animals and fauna are threatened as never before.

One of the responses to that destruction has been the establishment of zoos and wildlife parks where animals exist as a spectacle, an entertainment in an educational ark.

They may be physically present but the context is wrong, the wild spirit absent. It may be time to reappraise the value of these legacy institutions, just as was done with the tradition of performing circus animals which have been banned in more and more countries.

That inspectors have raised concerns about the National Reptile Zoo, after rare turtles died within days of arriving in Kilkenny, is another alarm call.

Some years ago 159 animals died at Fota, including 18 corncrakes. That toll was more than double that at Dublin Zoo, where 68 animals died. Many may have been natural but other factors may be relevant too.

Commercial reality exacerbates welfare issues. Profits at Fota — €294,599 — fell 65% last year while the Zoological Society of Ireland, which operates Dublin Zoo and Fota, fell by 71% from €2.6m to €765,000.

The sharp drop came as Dublin visitor numbers fell more than 8%. There are many reasons for this, including the papal visit, but whether it is a blip or a trend remains to be seen.

Nevertheless, it raises a challenging question: Has Attenborough’s work made the idea of exhibiting animals held in life-long captivity obsolete?

Has his magnificent hummingbird footage made shabby, bored captive bears seem something far less noble than they are?

These institutions do much more than exhibit animals — Fota has released 1,250 natterjack toads in Kerry to help bolster a dwindling population.

This is priceless work, so maybe it’s time for a change of emphasis. Maybe the protection of habitat and the animals dependent on it, like corncrakes and curlews, is today’s primary mission.

How that might be funded without exploiting a cast of captive animals seems the real question. Do we really need to visit a zoo or a wildlife park to support animal or habitat protection?

The answer is, surely, all too obvious in Attenborough’s films.