Chignecto Isthmus - A land bridge EarthCache

Chignecto Isthmus - A land bridge

An “isthmus” is a narrow strip of land, with water on either side, that connects two larger bodies of land. The Chignecto isthmus separates the waters of Chignecto Bay, a sub-basin of the Bay of Fundy, from those of Baie Verte, a sub-basin of the Northumberland Strait that is an arm of the Gulf of St. Lawrence. The isthmus stretches from its northerly point at an area in the Petitcodiac River valley near the city of Dieppe, New Brunswick to its southerly point at an area near the town of Amherst, Nova Scotia. At its narrowest point between Amherst and Tidnish, the isthmus measures 24 kilometres wide. Because of its strategic position, it has been important to competing forces through much of its history of occupation.

The name "Chignecto" derives from the Mi'kmaq name Siknikt, meaning "drainage place"; the name of the Mi'kmaq District where the isthmus is located. The Missaguash River (French: Rivière Missaguash) is a small Canadian river that forms the southern portion of the inter-provincial boundary between Nova Scotia and New Brunswick on the Isthmus of Chignecto. It had historic significance in the 18th century as the de facto border between French (to the west) and English-controlled territories.

The majority of the lands comprising the isthmus have low elevation above sea level; a large portion comprises the Tantramar Marshes, as well as tidal rivers, mud flats, inland freshwater marshes, coastal saltwater marshes, and mixed forest. Several prominent ridges rise above the surrounding low land and marshes along the Bay of Fundy shore, namely the Fort Lawrence Ridge (in Nova Scotia), the Aulac Ridge, the Sackville Ridge, and the Memramcook Ridge (in New Brunswick). The towns of Amherst, NS and Sackville, NB are located on the Isthmus itself.

In contrast to the Bay of Fundy shoreline in the west, the Northumberland Strait shoreline in the east is largely forested, with serpentine tidal estuaries such as the Tidnish River penetrating inland. The narrowest point on the Northumberland shoreline is opposite the Cumberland Basin at Baie Verte. If sea levels were to rise by 12 meters, the isthmus would be flooded, effectively making mainland Nova Scotia an island.

The Isthmus is an important transportation corridor with the Trans-Canada Highway and inter-provincial railway crossing over it.  It also carries the hyrdo and natural gas connections between Nova Scotia and the rest of North America. It is the only route for terrestrial wildlife to move in and out of Nova Scotia. Without deliberate planning to conserve ecosystem connectivity, development on the Isthmus could restrict the natural movement of plants and wildlife across this important land bridge.

Visit the Beaubassin and Fort Lawrence National Historic Sites at N45° 50.882' W64° 15.667' for another view and more history.

To log this Earthcache please answer the following questions and send in a timely manner to my geocaching profile or email. Answers not received will result in deleted logs. Look North - West towards the river.

1. What is the height of the land here above sea level?

2. How does measured height differ from height at Missaguash River?

3. Estimate the width of the Missaguash river?

4. What would happen if the Isthmus was flooded?  

5. Post a picture of the isthmus or the area.

[REQUIRED] In accordance with the updated guidelines from Geocaching Headquarters published in June 2019, photos are now an acceptable logging requirement and WILL BE REQUIRED TO LOG THIS CACHE. Please provide a photo of yourself or a personal item in the picture to prove you visited the site.