Changes in the fish species composition of all Austrian lakes >50 ha during the last 150 years

Abstract

The fish communities of all Austrian natural lakes (n ¼ 43) larger than 50 ha in surface area were assessed and the historical fish communities in c. 1850 were reconstructed. During the last 150 years, the fish communities of Austrian lakes have altered: in 49% of lakes at least one indigenous fish species, usually sensitive or small-bodied taxa, is now missing. Conversely, in all but one of the 43 lakes the number of fish species has increased. In particular, certain fish species of interest to angling and commercial fisheries now occur in more lakes. Generalised linear models were used to identify variables that would explain the loss of fish species using categories of lake use (ranking score). The category human population density around the lakes seemed to be one of the main causes for the loss of fish species. K E Y

Comparison of three standardised fish sampling methods in 14 alpine lakes in Austria

“…Local fisheries managers have broad experience with, and knowledge of, their lakes and were often able to provide evidence of rare or hard‐to‐catch species. It was important to test the catch statistical data critically to assess the reliability of the methods used (Zick et al. 2006), and in general, the information provided was very informative.…”

“…Up‐to‐date catch statistics and personal communication with the fisheries managers helped to identify species that were not detected by the sampling methods used. The information provided was checked for plausibility (Zick et al. 2006), and documented species were added to the list of species in each lake.…”

‘Global worming’: first record of an epidemic of Triaenophorus crassus in a population of Arctic charr Salvelinus umbla

“…During the last century, the uncontrolled introduction of alien and translocated species increased throughout Europe, and natural fish communities were severely disturbed (Cowx, 1998; Zick et al , 2006). Originally, only eight fish species occurred in the Lake Grundlsee [ S. umbla , lake trout Salmo trutta f. lacustris L., minnow Phoxinus phoxinus (L.), Danube bleak Chalcalburnus chalcoides (Güldenstädt), European chub Squalius cephalus (L.), bullhead Cottus gobio L., burbot Lota lota (L.) and stoneloach Barbatula barbatula (L.)].…”

The development of stocked eels (Anguilla anguilla) in previously eel‐free Austrian Alpine lakes

“…or starlet ( Acipenser ruthenus L.) were introduced into Austrian Alpine lakes to enhance commercial and recreational fisheries (Zick et al. ). The development of new transportation methods had made it easier to ship large quantities of live fish in oxygenated and cooled water tanks (Berka ).…”

“…Beginning in the early 1950s, 13 new fish species such as North American lake trout (Salvelinus namaycush Walbaum), grass carp (Ctenopharyngodon idella Val.) or starlet (Acipenser ruthenus L.) were introduced into Austrian Alpine lakes to enhance commercial and recreational fisheries (Zick et al 2006). The development of new transportation methods had made it easier to ship large quantities of live fish in oxygenated and cooled water tanks (Berka 1986).…”