All the animals at Whipsnade Zoo in Bedfordshire, from little lemurs to enormous elephants, are being weighed and measured in an annual survey.
It's a huge task for keepers as they began the task of cataloguing each one of its 2,500 animals. The heights and weights of 200 species are being recorded.
Click below to watch a report by ITV News Anglia's Claire McGlasson
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Despite the sunny spells, in-between the scattered showers, it will feel colder compared to Sunday, helped by the breezy conditions.
Norwich City moved up to third in the Championship table after taking all three points in the vital derby clash against Ipswich Town
Cold with wintry showers this evening and during Monday.