Multispecies fish tracking across newly created shallow and deep habitats in a forward-restored lake

• Published in: Movement ecology 2023-07, Vol.11 (1), p.43-43, Article 43
• Main Authors: van Leeuwen, Casper H A, de Leeuw, Joep J, van Keeken, Olvin A, Volwater, Joey J J, Seljee, Ferdi, van Aalderen, Roland, van Emmerik, Willie A M, Bakker, Elisabeth S
• Format: Article
• Language: English
• Subjects: Acoustic telemetry; Aquatic ecological zones; Archipelagoes; Cyprinidae; Deep sand excavation; Deep water; Excavation; Fish nursery; Fish reproduction; Food; Food chains; Forward-looking restoration; Freshwater fish; Freshwater lakes; Guilds; Habitats; Heterogeneity; Human impact; Human influences; Lake renewal; Littoral environments; Macro-invertebrates; Marker Wadden; Omnivores; Perca fluviatilis; Percidae; Rivers; Sand; Shallow water; Shorelines; Spawning; Species; Spring; Spring (season); Tracking; Turbidity; Water depth; Wind effects
• ISSN: 2051-3933; 2051-3933
• DOI: 10.1186/s40462-023-00405-1

Freshwater fish communities typically thrive in heterogenous ecosystems that offer various abiotic conditions. However, human impact increasingly leads to loss of this natural heterogeneity and its associated rich fish communities. To reverse this trend, we need guidelines on how to effectively restore or recreate habitats for multiple fish species. Lake Markermeer in the Netherlands is a human-created 70,000-ha lake with a uniform 4 m-water depth, steep shorelines, high wind-induced turbidity, and a declining fish community. In 2016, a forward-looking restoration project newly created a 1000-ha five-island archipelago in this degrading lake, which offered new sheltered shallow waters and deep sand excavations to the fish community. In 2020, we assessed how omnivorous and piscivorous fish species used these new habitats by tracking 78 adult fish of five key species across local and lake-scales. We monitored spring arrival of adult fish and assessed local macro-invertebrate and young-of-the-year fish densities. Adult omnivorous Cyprinidae and piscivorous Percidae arrived at the archipelago in early spring, corresponding with expected spawning movements. During the productive summer season, 12 species of young-of-the-year fish appeared along the sheltered shorelines, with particularly high densities of common roach (Rutilus rutilus) and European perch (Perca fluviatilis). This suggests the sheltered, shallow, vegetated waters formed new suitable spawning and recruitment habitat for the fish community. Despite highest food densities for adult fish in the shallowest habitats (