Zoe, 48, took on the role as host of BBC Radio 2’s Breakfast Show after 53-year-old presenter Chris stood down in January to take on duties over at Virgin Radio.
The Strictly Come Dancing It Takes Two host had a successful run at the start of the year but has since seen figures drop for the Breakfast show.
According to Rajar, Zoe has lost 780,000 weekly listeners for the second quarter of the year.
Recent reports mean the radio programme has suffered its lowest audience figures in over nine years, with the last drop seen back in 2010.
Although Zoe’s audience figures have dropped, the industry body has reported the Breakfast Show is still the most popular for the time slot.
Compared to this time last year when Chris was fronting the show, the former BBC Radio 2 presenter had 800,000 more listeners than his successor.
The decrease in figures has meant an increase elsewhere on the station, with Ken Bruce’s mid-morning show seeing more listeners tuning in.
Ken, 68, has seen his audience figures boosted, making his show the most popular radio programme in the UK with 8.49 million listeners.
Of the news, Ken told the BBC: “After 34 years as a part of the BBC Radio 2 family, I'm astounded that the allure of my daily grumpy musings, coupled with PopMaster, continue to entertain.
“Many thanks to the long-suffering listeners,” he continued.
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