Wildlife experts and more than 100 children will give a petition at Buckingham Palace on Saturday.
They will be led by a jazz band, and participants include the choir SOS From the Kids, who will perform and perform a song that appeared on Britain’s Got Talent in 2019.
Broadcaster Mr Packham is due to deliver a speech outside the palace, while a four-metre-tall statue of a white stork will carry a giant envelope symbolizing the petition in its beak.
The Wild Card campaign is urging the royal family, who own 1.4% of the land in the UK, to conserve nature on their estates before appearing as ambassadors at the Cop26 climate summit in November.
build on an open letter to Queen Sent in June by more than 100 scientists and celebrities, including Hugh Fernley-Whittingstall, Kate Humble and Anita Rani, the petition sheds light on the issues of royal land.
The campaign states that the average tree coverage in the European Union is 37%, while the Duchy of Cornwall property owned by the Prince of Wales has only 6% tree coverage.
Ecologists believe the royal estates will naturally contain beavers, wolves, bison, wild boars, pine martens and white storks, which could be introduced if they go wild again, campaigners have said.
The wild card campaign more broadly calls for 50% of the UK to be completely wild again, calling on the royal family as the UK’s largest landowner to act first.
Royal-owned territories include the Crown Estate and the Duchy of Lancaster and Cornwall.