For the past two years the volunteer group has been creating a sea lion forest for the critically endangered species.
Chairman Bradley Curnow said aim of the project was to expand the area that was suitable for sea lion habitat.
"We have been growing this forest in the hope that sea lions will come back and discover it and think what a good place this is to have a pup."
The trust had a 10-year agreement with the Department of Conservation to work on about 3ha of Doc land near Aramoana Beach and the project was supported by the Dunedin City Council biodiversity fund, he said.
During the past two years volunteers had planted about 3000 native plants, including ngaio, olearias, broadleaf, toetoe, flax, Coprosma crassifolia, manuka and Pittosporum tenuifolium.
The group was also weeding out introduced species beside the beach, including the marshmallow plant.
In the Aramoana salt marsh they were removing Australian ice plant.
"It inhabits the salt marsh and forms blankets eliminating everything else."
By removing the Australian ice plant the native New Zealand ice plant was able to flourish instead.
The group also worked to control Juncus gerardii and sea couch on the salt marsh.
The group had observed indications that sea lions were beginning to take advantage of the redeveloped area.
Sawyers Bay photographer Jan Pearman has been volunteering for about two years at the sea lion forest and recently became a trustee.
As an abstract photographer she spent a lot of time at Aramoana and enjoyed "giving back" by taking part in planting and weeding activities, she said.
"It is such a beautiful place.
"Give it 10 years and this will be an absolutely brilliant native area."
