## 4 Discussion  
The main aim of the present study was to initiate and design a monitoring plan for temporary aquatic habitats that are of naturalistic concern but that have been neglected for a long time despite their inclusion in the Habitat Directive. Indeed, detailed wetland inventories are lacking in large areas of the world (e.g., Asia, South America) [26], and overall, small wetlands are often disregarded or not identified in regions where inventories are made [43]. In this study, our inspection and monitoring activities highlighted the great importance of these habitats within the coastal water network. In fact, of all coastal water bodies, more than a third (53/137) were temporary, and these were evenly distributed within the study area. Their occurrence, from autumn to spring, allows the increased dispersion of many organisms that do not find available habitats during the dry months. Indeed, temporary ponds are often used as breeding spots for amphibians (see Introduction) because the distribution of such wetlands guarantees continuity along the entire coast and serves as an important ecological corridor for both native and alien organisms in dispersion and/or migration, such as the smooth newt _Lissortirion vulgaris_ (observed within ponds from group C) and the non-native red swamp crayfish _Procambarus clarkii_ (groups D and E). From a conservational point of view, the finding of three different types of habitats listed in the main international conventions for environmental protection is significant, with particular reference to the priority habitat 3170\", which was the most abundant habitat on the entire coastline. Mediterranean temporary ponds are a peculiar type of temporary wetlands, which mainly occur around the Mediterranean basin in southern Europe and North Africa, but also in other regions with a Mediterranean climate (i.e., mild and rainy winters, hot and dry summers) [44]. Mediterranean temporary ponds in southern Europe are an EU Priority Habitat under the auspices of the Habitats Directive, and special protections apply in several Mediterranean countries [28; 45]. These very shallow ponds are present only during winter and late spring and harbour several rare or threatened species of plants, amphibians, and invertebrates listed in international conventions (the Habitats Directive, the Bern Convention, and the IUCN Red List) [9]. The preservation of such habitats is also a priority of the Mediterranean Wetlands Strategy, which aims at \"stopping  
\begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline
**Group** & **Site** & **O\({}_{2}\) (mg/L)** & **O\({}_{2}\) (\%)** & **T\({}_{4m}\)** & **T\({}_{w}\)** & **pH** & **PO\({}_{4}\)\({}^{3-}\)** & **NO\({}_{3}\)\({}^{-}\)** & **EC** \\ \hline  
and reversing the loss and degradation of Mediterranean wetlands as a contribution to the conservation of biodiversity and sustainable development in the region\" [1]. In this study, only MTPs have been monitored over time in order to survey both hydroperiod and surface size. To collect information on occurrence and surface size, the use of UAVs was preferred to satellite images because of limitations in data availability in adverse atmospheric conditions and sensors' spatial resolution [46]. However, the current progress of remote-sensing technologies appears promising for improving the detection and mapping of small wetland features [46; 47]. Over the last decade, the use of drones for both civilian and scientific purposes has aroused growing interest, so much as to mark the beginning of a new era of remote sensing [48] in the study of the environment [49]. Indeed, drones represent a relatively risk-free and low-cost way to observe natural phenomena rapidly and systematically at high spatial and temporal resolutions [50]. For these reasons, drones have recently become a major trend in wildlife research [51; 52] and management [53; 54; 55].