Animal activists are preparing for possible skirmishes in Canberra's nature reserves after the government announced plans to cull 2000 kangaroos.

The government said on Friday that multiple nature reserves would be closed in the evenings from Monday, May 16, while staff moved to control the population of eastern grey kangaroos.

Robyn Soxsmith, of the Animal Protectors Alliance, said the group was determined to stop the kangaroos being shot. Credit:Jay Cronan

The cull was necessary to protect biodiversity and minimise impacts on other flora and fauna in critical grassland and woodland, director of parks and conservation Daniel Iglesias said.

But animal activists say they have no plans to hold back their efforts to stop the culls and scare off kangaroos, even as some face penalties and fines in court.