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Submarine channels are key features for the transport of flow and nutrients into deep water. Previous studies of their morphology and channel evolution have treated these systems as abiotic, and therefore assume that physical processes are solely responsible for morphological development. Here, a unique dataset is utilised that includes spatial measurements around a channel bend that hosts active sediment gravity flows. The data include flow velocity and density, alongside bed grain size and channel‐floor benthic macrofauna. Analysis of these parameters demonstrate that while physical processes control the broadest scale variations in sedimentation around and across the channel, benthic biology plays a critical role in stabilising sediment and trapping fines. This leads to much broader mixed grain sizes than would be expected from purely abiotic sedimentation, and the maintenance of sediment beds in positions where all the sediment should be actively migrating. Given that previous work has also shown that submarine channels can be biological hotspots, then the present study suggests that benthic biology probably plays a key role in channel morphology and evolution, and that these need to be considered both in the modern and when considering examples preserved in the rock record. [ABSTRACT FROM AUTHOR]

Author(s): P. J. Talling (corresponding author) [1]; R. B. Wynn [2]; D. G. Masson [2]; M. Frenz [2]; B. T. Cronin [3]; R. Schiebel [2]; A. M. Akhmetzhanov [2]; S. [...]

In the northeast Atlantic, much of the deep cold water flow between the Norwegian Sea and the main North Atlantic basin passes through the Faroe-Shetland and Faroe Bank Channels, generating strong persistent bottom currents capable of eroding and transporting sediment up to and including gravel. A large variety of sedimentary bedforms, including scours, furrows, comet marks, barchan dunes, sand sheets and sediment drifts, is documented using sidescan sonar images, seismic profiles, seabed photographs and sediment cores from the floor of the channel. Published information on current velocities associated with the various bedforms has been used to reconstruct the pattern of bottom currents acting on the channel floor. The results broadly reflect the current pattern predicted on the basis of regional oceanographic observations, but add considerable detail. The internal consistency of the results suggests that the methods used are robust, giving confidence in the fine detail of the observed bottom current structure. Bottom current velocities in the range <0.3 to >1.0 m s-1 are indicated by the range of observed bedforms, with the strongest currents associated with south-west transport of Norwegian Sea Deep Water (NSDW) at water depths of 800-1200 m. The main NSDW flow forms a relatively narrow core that follows the base of the Faroes slope. This core follows the 900 change in trend of the Faroes slope at the junction between the Faroe-Shetland and Faroe Bank Channels. The strongest currents within the NSDW core are found over the shallowest sill in the Faroe-Shetland Channel and in the narrowest part of the channel immediately downstream of the sill, and are generated by topographic constriction of the flow. Eastward flow of deep water along the northern flank of the Wyville-Thomson ridge suggests a complex current pattern with some recirculation of deep water within the deep Faroe Bank Channel basin. The observations suggest that Coriolis force is the main agent controlling the westward deflection of the NSDW into the Faroe Bank Channel, contradicting a previous suggestion that this was controlled by the topography of the Wyville Thomson Ridge. [ABSTRACT FROM AUTHOR]

The article presents the author's insights on first Scottish record of Balearie Woodchat Shrike in Westray, Scotland on May 26, 2013. It says that the rest of the bird that he saw had no sign of a white patch at the base of the primaries and inflight revealed very restricted pale bases. The author states that the shrike was settled and spent its time feeding on bumblebees and other insects. The author adds that when he returned to the site, he sees the bird lingers at an exposed site overnight.