GSA 20, located in the Central Mediterranean Sea, extends on an area of 16823 km². The MEDITS survey has been carried out in this region since 1994, primarily during the third quarter of the year, with an initial sampling intensity of about 31 hauls per year (1994-2001), increased  to 36 hauls per year  in 2002 The survey was not conducted in the following years: 2002, 2007, from 2009 to 2013, 2015 and 2017.