Nature Trust of New Brunswick

Green Island Nature Preserve – Florenceville, NB

Photo Credit: Iowa State University

Florenceville-Bristol, New Brunswick


The Green Island Nature Preserve is an ecologically significant island located north of Florenceville in the St. John River. This nature preserve is 8 hectares (20 acres) in area and is home to the endangered cobblestone tiger beetle (Cicindela marginipennis) and the very rare Anticosti aster (Symphyotrichum anticostense).


The island was used by First Nations people and was subsequently occupied by early settlers.


Green Island is a combination of wetland and woodland. It is home to the Anticosti aster (Symphyotrichum anticostense) which is federally listed as a threatened species. This nature preserve acts as the first formal protection to this plant in New Brunswick. This species of aster has a range from the upper shores of the Restigouche and St. John Rivers, to the Gaspé Peninsula, Anticosti Island, and northern Maine.  The Anticosti aster is a slender perennial plant that grows 50-60 cm tall. Its small daisy-like flowers bloom in late summer, have a yellow centre and pale purple or blue outer rays grown on very long stalks. The leaves are very narrow and often arching. The Anticosti aster is dependent on cyclic disturbances caused by high spring waters to keep shrubs and other competing species from taking over their habitat.

This preserve is also a home to the endangered cobblestone tiger beetle (Cicindela marginipennis). The island provides a favourable habitat for the cobblestone tiger beetle because it is an alluvial floodplain and is partially submerged annually. The cobblestone tiger beetle is endangered due to its limited geographic distribution and small population. The favourable habitat for the cobblestone tiger beetle is formed by flooding during the spring freshet and the water flow patterns created by the presence of nearby islands and beaches.

Access and Activities

This preserve can only be accessed by boat. Because of the endangered species, please view this island from the shore or take a paddle in the St. John River. The best place to view this island and is from the Trans-Canada Trail near Florenceville-Bristol or from Route 130 on the west side of the Saint John River.

View or navigate to this preserve via Google Maps.

Click the map below for more detail.

*The property is undeveloped and there are a variety of hazards and risks associated with accessing this preserve. While this nature preserve is open for public access, visitors must assume responsibility for their own actions and safety and are to use the land at their own risk.*


The Nature Trust of New Brunswick
404 Queen St. 3rd floor
P.O. Box 603, Station A
Fredericton, New Brunswick E3B 5A6
Phone: (506)457-2398
Fax: (506)450-2137

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