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Lakes provide ecosystem services such as water resources, tourism, biodiversity, and fishing, and therefore their management represents important societal challenges. Since the early 1960s, significant anthropogenic pressures (human population growth and industrial and agricultural development) have accelerated the degradation of lake ecosystems, leading to eutrophication and subsequent increased sedimentation on fish spawning grounds and decreased dissolved oxygen concentrations. This negatively affects the natural recruitment of whitefish (Coregonus lavaretus), an emblematic species of peri-alpine lakes. Over the years, such processes have resulted in a decline in the whitefish population stock, thereby leading to a drastic drop in catch and causing major economic losses. From the beginning of the 1980s, alongside the restoration of water quality, professional fishers, recreational anglers, state services, and researchers from INRA worked together to develop an applied research program called 'Pacage Lacustre' to improve and optimise salmonid stocking. The goal was to counterbalance the low juvenile natural recruitment and maintain whitefish populations. Here, we retrospectively retrace the key stages of this research program and its main impacts on society. Collaborative efforts played a key role in rehabilitating whitefish populations in lakes Geneva and Bourget, particularly when their abundances were the lowest. Therefore, these efforts had a substantial impact on preserving commercial and recreational fishery activities, in addition to favorable societal impacts, highlighting the importance of such collaborative work. From the beginning of the 1980s, professional fishermen and recreational anglers, together with state services and researchers from INRA, developed an applied research program focusing on the improvement and optimisation of salmonid stocking in the Lakes Geneva and Bourget. The aim of thispaperis to retrospectively retrace the key stages of this program and its main impacts on society. [ABSTRACT FROM AUTHOR]

[Display omitted] Tracking the behavior of invasive alien species (IAS) is challenging due to logistical constraints that hinder high frequency surveys. Real-time automated recorders offer a promising solution, but their feasibility needs testing and validation. The acoustic camera is an efficient method to obtain real-time records of the behavior of Hemimysis anomala , a mysid that has invaded a variety of aquatic ecosystems. This approach is also a valuable tool for high-quality video recordings of mysid swarms in shallow habitats. The feasibility of this device to record the continuous behavior, including exit and entry (hereafter referred to as emergence and homing) from a shelter over a diel cycle was validated. Emergence consistently correlated with the onset of civil twilight, while homing displayed more intricate temporal trends. Homing events were longer than emergence events, but both were significantly influenced by light conditions. The termination of emergence was concomitant to the onset of the light preference as already shown by past studies. However, homing showed an earlier onset before light conditions exceeded the preference values, possibly due to inter-individual variability and/or information sharing in swarm behavior. The survey also captured the collapse in the targets number detected by the end of March, underlining the termination of the winter swarm. Furthermore, we demonstrated the importance of high-frequency temporal resolution, with a sampling frequency of at least 10-min, to accurately capture the swarm behavior. Overall, we provide original new insights characterizing H. anomala ecology and encourage the development of real-time automated recorders to track the behavior of IAS. [ABSTRACT FROM AUTHOR]