Influence of Mediterranean Sea Temperature Increase on Gaeta Gulf (Tyrrhenian Sea) Biodiversity

In this study, temperature variations and invasion on marine fauna are investigated to ascertain their relationship in the Mediterranean at the Gaeta Gulf (Tyrrhenian Sea). Sea temperatures were collected from 1986 to 2009, the only period in which the AVHRR sensor installed on NOAA satellite was available. Changes in the sea surface temperature from satellite using GIS software were estimated. Research on marine species was carried out using the barcoding technique. Nine organisms of which one Anthozoa and one Malacostraca and eight belonging to Actinopterygii Class were barcoded from 2005 to 2019 and four of these were detected as non-indigenous species. The first sightings are related to Fistularia commersonii, and Sphoeroides pachygaster identified since 2009 and well reported in our previous publication. They have penetrated the Mediterranean from the Indian Ocean (through the Suez Canal) and from the Atlantic Ocean (Strait of Gibraltar) respectively and are still sporadic. These bioinvasions were linked for the first time to water heating, which increased by about 0.4 °C between 1989–1999 and 1999–2009. In addition, there are other identifications, such as Arothron diadematus from the Suez Canal, Percnon gibbesi from the Strait of Gibraltar; thermophilus indigenous species such as Pomadasys incisus and Astroides calycularis and sporadic autochthonous species such as Sudis hyalina, Tetragonurus cuvieri, Trachipterus trachipterus, and Remora osteochir. Non-native species and their invasions could lead to radical and sudden upheavals in the Mediterranean marine ecosystem and therefore require constant alert of sea surface temperature change.