The Secret Life of the Zoo (C4, 8pm)

CHESTER Zoo is Britain’s most popular zoo hosting 1.6 million visitors every year, but few ever see the world explored in this major new Channel 4 series. Using a range of filming techniques, including a micro-rig to capture animal behaviour close-up, this six-part documentary will take viewers behind the scenes – capturing in intimate detail both the remarkable behaviour of the animals and their close relationships with their keepers.

From a giraffe baby dropping six feet through the air as it’s born – to tigers moving house – to a pregnant viper being x-rayed, the series will present these spectacular rites of passage in the lives of rare animals as never before.

Chester Zoo opened on June10, 1931 and has been a conservation and education charity (North of England Zoological Society) since May 9, 1934. The North of England Zoological Society (NEZS) is the organisation that runs Chester Zoo and its conservation campaign, Act for Wildlife (actforwildlife.org.uk). It's a highly-respected centre for global conservation and research, and passionately campaigns for wildlife.

Charitable work extends across the UK and abroad, and the zoo supports and conducts around 100 field projects for conservation and education, through programmes spanning six geographic regions (South Asia, South East Asia, Latin America, Mascarenes and Madagascar, Africa, UK and Europe).

The zoo is home to more than 20,000 animals and in excess of 500 different species. Chester has been named the most visited paid-for attraction outside of London by the Association of Leading Visitor Attractions (ALVA) for the past four years and was, last year, was named the UK’s best zoo by users of the travel website, TripAdvisor.

One of our Nursery Team Lead Horticulturists, Keith Done, is retiring at the end of this month. Keith has worked at the Chester since 1969, and he thinks he is not only the current, but maybe also the "all-time" longest serving member of staff at Chester Zoo. Keith has lots of memories about George Mottershead (founder of Chester Zoo, who was featured in the BBC1 drama series Our Zoo), previous head gardeners, and the horticultural past.

The other long-serving staff members taking part in filming include: Niall Ormerod – lead keeper, primates – 44 years; Andrew Woolham – team manager, parrots and penguins – 31 years; Tim Rowlands – curator of mammals – 30 years; James Andrewes – assistant team manager, Twilight – 21 years; Alan Littlehales – lead keeper, elephant – 18 years; Anne Morris – lead keeper, parrots and penguins – 18 years; Chris Yarwood – lead keeper, primates – 17 years and Isolde McGeorge – specialist keeper, herpetology – 38 years.

Sugar Free Farm (ITV, 8pm)

NOW on day four of the sugar free diet, the celebrities are settling into the farm work but there is a tantrum over chickpeas in the pig field and a heated debate over dinner. Nutritionist Angelique Panagos tries to persuade them of the positives of a life without sugar, but even after a reality check at the hospital, Mark "The Beast" Labbett is still reluctant to listen. Olivia Colman narrates.

Back in Time for the Weekend (BBC2, 8pm)

MANY families are likely to while away much of their leisure time on their tablets, phones or computers – and the Ashby Hawkins are no exception. However, for this new series, the family are going back in time to find out how people entertained themselves before the advent of the internet. Presenters Giles Coren and social historian Polly Russell will be drawing on The Family Expenditure Survey, a government study which ran from the 1950s right through to 1999, to help guide the Ashby Hawkins as they visit a different decade each week. They begin in the 1950s, a time of formality and austerity, but while mum Steph struggles without the white goods, children Daisy and Seth discover there are upsides to living in the past.

Viv Hardwick