The monthly cruises currently involve eleven stations. Belgian marine scientists from all disciplines visit these stations on a regular basis for various research projects and monitoring programs since the early seventies.

Nine of these form a grid that encompasses the east-west and inshore-offshore gradients along the Belgian coastal waters. A tenth station (station B07) was selected to monitor as close as possible to the mouth of the Westerschelde estuary, which influences the coastal environment significantly. These ten stations are visited and sampled during a one-day trip.

On Station 421 only a CTD cast is being taken. Due to its distance off the coast this station could not be included in the one-day trip. It is visited during the monthly seabird census that is performed by the Institute for Nature Conservation with the Zeeleeuw. Both cruises are contiguous in the cruise schedule of the Zeeleeuw.

The monthly measurements are completed with seasonal samplings evaluating the tidal fluctuation of the parameters. These 13h-cycles are being performed on stations 120 (inshore) and 330 (offshore).

The following samples are taken :

• A depth profile of temperature, conductivity, turbidity and light penetration with a CTD equipped with a OBS sensor and PAR sensor
• Transparency of the surface waters with a secchi disc.
• A watersample with a Niskonbottel at 3m depth
• A sedimentcore with a Reineck boxcorer
• A phytoplanktonsample with a 10 µm mesh planktonnet is taken on stations 120, 215, 330, 700 and 421