Abandoned, lost, or otherwise discarded fishing gears (ALDFG), represent a major source of marine pollution worldwide, posing significant threats to biodiversity. This study assesses the influence of ALDFG on marine ecosystems along 300 km of the Valencian coastline (Spain), analysing the biodiversity responses following their removal in one (Benidorm) of the fifteen explored sites. Between 2022 and 2025, ten ghost nets and one discarded longline were detected and removed. During removal operations, benthic habitats and associated faunal communities were assessed through standardized underwater visual census conducted immediately after gear removal, followed by a survey based on horizontal and vertical transects.  Recovered gears were transported to the Fundación Oceanogràfic facilities, where associated organisms were identified and classified according to their interaction with ALDFG as: (i) entangled, (ii) associated, or (iii) exhibiting both interaction types. At the Benidorm site, a six-month post-removal monitoring survey was conducted to assess changes in benthic biodiversity following gear removal. Statistical analyses evaluated the randomic species distribution among ecological categories, the taxonomic patterns across phyla and the taxa contributing most to the observed differences. Concerning ghost nets, a total of 131 species belonging to eight phyla (Annelida, Arthropoda, Bryozoa, Chordata, Cnidaria, Echinodermata, Mollusca, Porifera) were recorded. Overall, 57.3% of species were entangled, 26.7% associated and 16% showed both interaction type. Mollusca were predominantly represented among entangled fauna (34.4%) and associated fauna (82.1%). The discarded longline hosted more than 2.700 egg capsules of Scyliorhinus canicula, highlighting artificial materials as potential oviposition substrates. At the Benidorm site, six months post-removal monitoring revealed an increase in Shannon diversity index (from 1.69 to 1.80), suggesting an early shift in community structure. Overall, this study provides new evidence on the taxon-specific ecological impacts of ALDFG, supporting the integration of biodiversity assessments into removal programmes to improve conservation and management strategies.