# Local Ecological Knowledge (LEK) Can Guide Decision-Making in Inland Fisheries Management
## 4 Discussion
### Fishers' Ecological Knowledge  
LEK has proven valuable in providing insights into the presence, abundance, population trends, biology, and ecology of fish species (i.e., [4; 5; 31]). Such studies have been conducted globally, primarily encompassing coastal areas in developing countries where scientific information is often insufficient for effective fisheries management [1; 4; 7; 32]. Among these studies, a considerable amount of research has focused on the reproductive cycles of various fish species, revealing information about the timing of spawning events, preferred spawning grounds, changes in fish behavior associated with reproduction, and even length at maturity [11; 33; 34]. LEK on length at maturity, yielding numerical data, offers the opportunity for statistical comparison with CSK and has been used as an index of overfishing [11]. It is important to note that formal statistical comparison between CSK and LEK is often challenging [35], although scientists argue that efforts should be made to align them in similar terms for the purpose of comparison [11; 29]. The fishers of the Polyphytos Reservoir are primarily familiar with species of economic importance. Mentions of _Anguilla anguilla_ in their responses reflect historical knowledge, as this species can no longer reach the reservoir due to downstream dam construction along the Aliakmonas River that has interrupted its continuity. The length at first maturity, as reported by local fishers in this study, occasionally differed from the lower limit documented in the existing literature. It is crucial to highlight that in the literature, information on sexual maturity may refer to the median or mean length at which 50% of the population achieves maturity for the first time. This distinction might not be apparent to the fishers, who were specifically asked about the length of the smallest mature specimen. The lack of awareness among many fishers concerning the size of first maturity stems from their common use of large-sized nets or hooks, primarily targeting larger individuals. This results in a lack of personal observations on the maturity of smaller-sized individuals. Fishers' observations on the breeding periods of commercial species closely align with the literature's findings [22; 36]. Most species typically spawn during spring. However, according to the literature, northern pike, typically reproduces during the winter months, generally between February and April [22]. It is essential to recognize that these studies were conducted in northern countries with colder winter temperatures, which may differ from those in southern Mediterranean countries, such as Greece. Hence, the interviewed fishers may accurately believe that the species' spawning peak is in February. In contrast, wels catfish, based on various sources [22; 37], is reported to spawn from April to June. Nevertheless, some sources suggest a more extended spawning period from early June to August [38], consistent with the observations from interviewed fishers. Given the substantial presence of giant individuals of this species in the ecosystem, a focused study on its reproduction in the lake would be particularly valuable. From the above, it becomes clear that the fishing ban period in the Reservoir does not encompass the entirety of the commercial species targeted by professional fishers, such as the northern pike and the wels catfish. These specific species are mainly caught with fyke nets, therefore, contemplating a prohibition on the use of these specific fishing tools during their reproductive periods could be examined as an additional management measure for their protection. Additionally, the initiation of the fishing prohibition period in the lake should be reconsidered. According to the consensus among fishers, the start of the prohibition period is later than the onset of common carp reproduction, leading to overfishing of the species stock. Implementing a complete ban on common carp fishing throughout its reproductive period would contribute to its protection.