Black Sea Bream is a marine fish that nests and spawns on the seabed off the south coast of the UK. One spawning area is located close to one of Cemex’s Marine Licence extraction areas off the Sussex coast. There is a Marine Conservation Zone (MCZ) in place, and we arrange the monitoring of the nests every year to ensure our activity is not having a detrimental effect.

The first and second phases of this year’s Black Sea Bream nest survey have been completed by environmental consultants, ABPmer. During the first phase, a survey vessel runs across parts of the MCZ and geophysical sensors generate an image of the seabed tens of metres across.

Black Sea Bream create nests by moving sediment to expose the underlying bedrock on which they lay their eggs. Changes in backscatter between the sediment and bedrock show up as contrasting shades. Dense nests have once again been identified (the dark dots on the image), each measuring 1m to 2m across.

The second phase involves lowering an underwater video camera into the water column and visually reviewing nests observed in the geophysical data.