Site details

(lookup in gazetteer)
Flag of Norway
2 stars - De facto protected because of geographical conditions and location
Normal Focal Site

Map type: Google Maps  SVG (dynamic)  Image (static)

Lophelia reefs are common at several locations in the Trondheimsfjord, as shallow as 39m. Photo: HT Rapp

Synoptic description of site:

A open fjord, 130 km long, with three basins separated by tresholds. The fjord has mostly all kind of habitats and is well studied.

Extensive description of site:

The Trondheimsfjord situated in Mid-Norway, is 130 km long, having three sills with deep-water basins in between. Mean salinity is about 34psu and bottom temperature 7C. Soft and hard bottoms, as well as estuaries are present.

Habitats present:
Seagrass beds 

Description of fauna and flora:

The fauna and flora are well documented and have been researched since 1760. The deep-water corals with associated fauna are especially conspicuous.

Pristiness: High


Above treshold depth the fjord is influenced by transport of coastal water with reneval of ca 60 days. The deep water is changed once every year.

Human impact:

The area is subject to a low level of pollution from the area bordering the fjord, especially from Trondheim (pop.170,000), but the deeper parts of the fjord are little influenced. Commercial trawling and salmon farms are kept to a minimum.


All facilities for marine biodiversity research are available, from research vessel, fully equipped laboratories, indoor and outdoor basins, and a University Library.

Available database and website:

The Museum has an inventory of its collections, a long time (> 30 years) series of hydrographic data, and a literature database. The biological station has its own website

Dataset covering this area:


Commitment and ongoing research:

The Trondhjem Biological station and Institute of Natural History at the Norwegian University of Science and Technology undertake biodiversity-related research in the area. Future activity will be concentrated on projects using ROV techniques both for in situ video studies and also using technical installations.

Additional Information: Lists with the marine bottom organisms known from the Trondheimsfjord can be found in Brattegard, T. & T. Holthe (eds) 1997. Distribution of marine, benthic macroorganisms in Norway. Research Report for DN 1997-1. Directorate for Nature Management.