{"title":"Are perch (Perca fluviatilis L.) getting larger or smaller in Swedish lakes?","authors":"Holmgren Kerstin, Erik Petersson","doi":"10.1111/eff.12719","DOIUrl":null,"url":null,"abstract":"Space- for-time approaches are often used to indicate current or future changes over time. A European gillnet standard facilitates spatial-scale comparisons of fish communities in European lakes. Fish size was generally lower and densities higher in warmer lakes, but less is known about trends over decadal time scales. We analysed the size of European perch ( Perca fluviatilis L.) in 2121 Swedish lakes sampled during 1996– 2021. The aim was to test whether size changed over time, and whether trends were similar in southern and northern regions. We analysed mean length and occurrence or relative abundance of size classes from the smallest ( < 100 mm) to the largest individuals (≥350 mm), and length at 1 and 5 years. The large data set was used to find general trends over time within regions, and within-lake trends were tested for 40 time-series lakes. The mean length of perch decreased in the southern and increased in the northern region. The proportion of the smallest perch increased","PeriodicalId":11422,"journal":{"name":"Ecology of Freshwater Fish","volume":"32 4","pages":"735-749"},"PeriodicalIF":1.6000,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/eff.12719","citationCount":"1","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Ecology of Freshwater Fish","FirstCategoryId":"97","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1111/eff.12719","RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"FISHERIES","Score":null,"Total":0}
引用次数: 1
Abstract
Space- for-time approaches are often used to indicate current or future changes over time. A European gillnet standard facilitates spatial-scale comparisons of fish communities in European lakes. Fish size was generally lower and densities higher in warmer lakes, but less is known about trends over decadal time scales. We analysed the size of European perch ( Perca fluviatilis L.) in 2121 Swedish lakes sampled during 1996– 2021. The aim was to test whether size changed over time, and whether trends were similar in southern and northern regions. We analysed mean length and occurrence or relative abundance of size classes from the smallest ( < 100 mm) to the largest individuals (≥350 mm), and length at 1 and 5 years. The large data set was used to find general trends over time within regions, and within-lake trends were tested for 40 time-series lakes. The mean length of perch decreased in the southern and increased in the northern region. The proportion of the smallest perch increased
期刊介绍:
Ecology of Freshwater Fish publishes original contributions on all aspects of fish ecology in freshwater environments, including lakes, reservoirs, rivers, and streams. Manuscripts involving ecologically-oriented studies of behavior, conservation, development, genetics, life history, physiology, and host-parasite interactions are welcomed. Studies involving population ecology and community ecology are also of interest, as are evolutionary approaches including studies of population biology, evolutionary ecology, behavioral ecology, and historical ecology. Papers addressing the life stages of anadromous and catadromous species in estuaries and inshore coastal zones are considered if they contribute to the general understanding of freshwater fish ecology. Theoretical and modeling studies are suitable if they generate testable hypotheses, as are those with implications for fisheries. Manuscripts presenting analyses of published data are considered if they produce novel conclusions or syntheses. The journal publishes articles, fresh perspectives, and reviews and, occasionally, the proceedings of conferences and symposia.