The answer to this is explained within the very first chapter of the marvellous 1994 BOOK "THE ANIMALS CAME OUT TWO BY TWO" by David Taylor
Basically (David Taylor writes) ….. The Department of the Environment issued a set of official guidelines which would have to be adhered to if any organization wanted either to import dolphins or display them to the public in future. The crucial sections of these guidelines dealt with dolphin-pool dimensions. When the guidelines were issued it was obvious at once that none of the three British dolphinaria (Flamingo Land in Yorkshire, Brighton Aquarium and Windsor Safari Park) could, as they then were, comply. But at least the government gave them eight years to make the necessary alterations. In Windsor's case it clearly wasn't going to be a question of alterations. A whole new marine mammal complex would have to be built! The eight years would be up in 1993!
NOTHING AT ALL WAS DONE TO PLAN FOR THE 1993 DEADLINE!
When Windsor Safari Park was held up for sale in 1992 independent valuers stated it to be worth £20M
THE DOWNFALL AND LEGACY
Windsor's dolphinarium was one of the oldest in Britain, and looked it. Fundamentally it had changed little since the Smarts opened it in 1970 though its health and breeding record over the intervening years had been excellent and it had housed, as well as Atlantic bottle-nosed dolphins KILLER WHALES which on outgrowing the pool were then sold. Apart from the addition of an oval-shaped breeding pool in the mid-80s the dolphinarium remained more or less as originally constructed. On several occasions it had been tarted up to look more attractive to visitors but behind the layer of make-up the fabric was dilapidated. Even so, survey after survey had shown the marine mammal show to be the most popular attraction in the park! Windsor Safari Park NEEDED it's dolphinarium and prospective buyers knew it - and plenty of prospective buyers there were too!
But the cost of a new complex would run into several million pounds. Merely providing one suitably sized main pool with attendant filtration would cost around £800,000. Once built the running costs of the complex with its greatly increased volume of artificial sea water would be astronomic, a principal item being the electricity needed to pump some four million litres of water through the filters every two hours. The urgent necessity for a new dolphinarium, it's likely cost and the construction deadline (1993) were the main stumbling blocks on the way to buying Windsor Safari Park.
In a nutshell the park's DOLPHINS and KILLER WHALES had stolen the show from day one.
They had continued to steal the show all the way through the remaining years of the park and accounted for one massive part of the day that visitors loved and enjoyed the most. Losing this part of the park was unthinkable and yet it came with a massive price tag.
Effectively any prospective buyers - who may have been very enthusiastic upon arriving to bid for the park - soon learnt of "THE LEGACY" that was being handed down by the previous owners.
Investment in the the park's DOLPHINS and KILLER WHALES had recently been minimal. The requirements contained in the The Department of the Environment's official guidelines on what dolphinariums should look like in 1993, were sidestepped by both Southbrook and City Holdings when the official guidelines came out and then subsequently, by Themes International when they took over in 1988.
NOTHING WAS DONE! The 1993 deadline was "years away" but sadly this inaction was probably the final nail in the coffin for Windsor Safari Park. Prospective buyers simply would not buy the park with an outdated dolphinarium that could not meet the 1993 government guidelines, it was just too much too late.