Bear Seamount

Overview

Bear Seamount is the westernmost extinct volcano in a chain of undersea mountains known as the Western New England Seamounts. Bear Seamount is the oldest of the chain; it was most recently active 100 millions years ago. The seamount is formed of hard substrate and is dominated by invertebrate organisms that filter their food from the surrounding water. Several species of coral grow on the Western New England Seamount.1

Much like that of a geographically isolated terrestrial island, the flora and fauna of Bear Seamount exhibit a relatively high number of species that are isolated from other populations. Several species are also found on the other side of the Atlantic, indicating that the chain of seamounts of which Bear Seamount is part form a stepping stone for species crossing the Atlantic.2

Surface area

632 mi2 (1636.87 km2)

Depth

The surface of the seamount is 1500 m below sea level.3 The steep sides of the seamount drop over 1000 m to the floor of the continental slope.4

Bathymetry including key features

The seamount has been partially buried by the deposition of fine sediments. Unlike at least one other of the New England Seamounts, there is no erosion at its base; sediments form a smooth transition from the wall of the seamount to the seafloor.5

Substrate

The upper surface of the seamount is generally covered in thick deposits of sediment, there are outcrops of volcanic rock and variously sized rocks dropped by icebergs during glaciation.6

Information on average (seasonal/annual) oceanographic conditions

The seamount lies in the path of oceanic currents flowing southwesterly along the continental slope.7

1 New England Seabirds, Undated
2 Malakoff, D., 2003
3 Census of Marine Life, 2003
4 Moore, et al., 2003
5 U.S. Geological Survey GLORIA Mapping Program
6 Ibid.
7 Moore, et al. 2003