An animal-loving youngster was so upset after a red squirrel was knocked down on a road outside his home he urged forestry chiefs to erect warning signs.
Kielder is home to about 70% of England's remaining red squirrels
Luke Hodgson, six, wrote to the Forestry Commission after seeing the fate of the creature at Sidwood, near Greenhaugh, Northumberland.
They listened to his appeal and installed six warning signs.
The signs, which alert people to red squirrels crossing, were being unveiled on Tuesday.
Two large permanent signs have been installed near Luke's home and another four on the 14-mile drive between Kielder Castle and the A68.
His father Paul said: "Luke's always been keen on wildlife and loves spotting red squirrels.
"He's a very hands-on lad and it's typical of him that he should want to get something done to stop more squirrels suffering the same fate.
"The squirrels like to cross the road from our garden to reach some beech trees, which can put them in danger. Luke is thrilled by the new signs."
Luke and fellow pupils at Greenhaugh First School have been doing a project on red squirrel conservation.
Forestry Commission ecologist Tom Dearnley said: "We are doing our best to protect Kielder's red squirrels and Luke has played his part by suggesting the signs.
"The creature doesn't have the best road sense and needless deaths can be avoided by motorists driving slowly.
"The squirrels have found a real friend in Luke and we're pleased he likes the signs."