A founder of a leading East Anglian wildlife park and zoo, Lord Fisher of Kilverstone, has died after a short illness aged 91.

The landowner, local councillor and decorated naval officer closed the internationally-respected Kilverstone Wildlife Park after years of losses in late 1991.

Although it attracted about 160,000 visitors at the height of its popularity, the soaring costs of running a Latin-American zoo with about 700 creatures and employing 20 staff, became too great.

He also became the first peer of the realm to be elected leading citizen of Thetford since the town was entitled to have a mayor. In May 1962, he became Mayor of Thetford Borough Council and was re-elected a year later. When he had been first elected to the council in 1957, he had been on holiday in the United States and was informed of the result by cable.

John Vavasseur Fisher, who was born on July 24, 1921, went to Stowe and Trinity College, Cambridge. As the grandson of the famous Admiral of the Fleet, Lord (Jackie) Fisher, who was first sea lord during the first world war, he served in motor torpedo boats during the second world war. In 1944, he was awarded the Distinguished Service Cross for an action involving German E Boats.

He became heavily involved on the family's Kilverstone estate, growing produce including vegetables and especially carrots on the light Breckland soils. In 1964, he also had the vision to launch another new enterprise – marketing a butchered and jointed half hogget of Kilverstone lamb, weighing about 19lb, direct to the housewife, for the oven or deep freeze.

On his father's death in 1955, he became the third Baron Fisher of Kilverstone. He became involved in local affairs also serving on the former Wayland Rural District Council and held a number of posts with the local Conservative Association including president and also former treasurer for south Norfolk. Appointed a member of the Eastern Gas Board between 1962 and 1971, he pressed for the town to get access to the then cheaper source of energy, later North Sea Gas. He was a deputy lieutenant of Norfolk between 1968 and 1982 and had been appointed a magistrate after his election as Mayor in 1962.

He and his wife, Lady Fisher, opened the wildlife park on April 1, 1973, and it housed the only Latin-American zoo in the world. In the same year, as an additional attraction, he even introduced two new species of deer to the wildlife park – two pairs of Chinese water deer and two pairs of Muntjac.

Kilverstone, which became an important breeding centre where about 100 animals and 130 birds were bred each year, was internationally recognised for rearing endangered species including tamarins, spider monkeys and marmosets. Later, it became world famous for its Falabella miniature horses. At one stage, they owned the smallest horse in Britain, Victor, who stood just 26 inches high.

They always faced a challenge of huge overheads. In 1981, speaking in the House of Lords, he warned that the proposed Zoo Licensing Bill would have a 'crippling' effect and add further additional charges.

When he announced the park's closure, he said that it had lost money throughout most of the 1980s. He told the EDP: 'We've been living on optimism for 18 years, but the buck must stop here. My pocket has run out.' He was always prepared to stand his ground. In 1981, he won a legal battle with the tax authorities, who wanted to charge him Vat for leasing the shooting on the family's 3,000-acre estate. He had been shooting, his favourite hobby, since the age of 12 as he told the High Court when the cost of running a shoot became too high in the 1950s, he invited friends to contribute.

He had been living quietly for some years in Sussex and died in hospital at Eastbourne. He is survived by Lady Fisher and leaves two sons, two daughters and grandchildren. He is succeeded by his son, Patrick, the fourth baron.

Funeral arrangements to be announced.Michael Pollitt