A hundred kangaroos are the latest victims of Melbourne's development boom, trapped between their natural habitat, a new rail line and schools in the state's northeast.

The kangaroos, from three mobs at Mernda and Doreen, have been blocked from their habitat at Plenty Gorge Park due to construction of the new Mernda rail extension and two schools.

“The construction in the area has left the kangaroos trapped, with no access to the Gorge and no water unless it rains,” ecologist Shai Ager said on Monday.

“Kangaroos can last a while without water, but if they stay there, they could die within a couple of months, especially if an alpha male dies. We could see seven to 11 females stranded without protection.”

Ms Ager has created a change.org petition, calling on the Department Environment, Land, Water and Planning to relocate the kangaroos to their habitat “just 20 minutes down the road”.

It has garnered more than 9000 signatures in less than a week.

DELWP regional director Kelly Crosthwaite said the authority was working to keep the kangaroos safe.

“(We) will continue to work with Parks Victoria, the Level Crossing Removal Authority and the community to ensure the best and safest outcome for the kangaroos,” she said in a statement.

The department has sent wildlife officers to check on the kangaroos, which they said are in good health and have access to food and water.

They have also left construction gates open on weekends to allow kangaroos safe passage back to their habitat.

But Ms Ager labelled it a “poor effort”.

“It’s not at all realistic to think all individuals from all three mobs are going to happily wait until the weekends, find the small gate opening and hop across roads to get back to Plenty Gorge,” she said.

“DELWP just needs to step up, take responsibility, listen to the 10,000 people who support this relocation and get the job done.”

By Benita Kolovos