Naturalist Chris Packham slammed the University of Cambridge for putting “absolutely outrageous” anti-bird nets on a row of trees.
The protective net has appeared on more than 20 trees at the Whittle Laboratory on JJ Thomson Avenue in the city.
A university spokesman said the nets were added “to discourage birds from nesting” during construction work.
On Thursday evening, Extinction Rebellion climate activists cut and removed some nets.
Responding to the images posted on social media, Packham posted on Twitter: “Seriously? I thought we had been there last year!”
“This is absolutely outrageous.”
“Networks mean trouble”
The use of nets on trees, bushes and hedges to prevent bird nesting is not illegal – but has long been under the focus of conservation groups.
Packham said to the BBC, “At a time when many of our bird populations are in free fall and most people are trying to preserve them, these nets are totemic symbols of the destruction or disturbance of their habitat.”
If they weren’t properly adapted, he claimed that they were “shown to be lethal.”
“From my point of view … networks mean problems, so if you put them on you can expect them to follow.”
The university said the affected trees near the Whittle Laboratory “will be checked for wildlife three times a day.”
The spokesman did not confirm whether the trees would have been cut down.
Martin Fowlie of the RSPB, who asks for new guarantees, said that the decision to cover the branches is “morally doubtful”.
“In the midst of a climatic and wildlife emergency, we can’t continue squeezing nature into small spaces,” he said.
“Depending on the size of the shirt, it is difficult to rule out birds, which will go through gaps in search of food.”
The university was recently targeted by climate activists who organized a series of blockades and actions in the city.
Extinction Rebellion members reacted to bird nets by describing the university as “an enemy of nature” and removing some of the nets overnight.
“We have freed some of the @Cambridge_Uni trees from their nets,” tweeted the group.
“Habitat destruction is the number one reason for the collapse of British birds. This practice must stop.”