Fauna norvegica 2020-10-16T12:27:02+00:00 Fauna norvegica Open Journal Systems <p>Fauna norvegica is an international journal focusing on Nordic fauna. In addition to faunistic studies, contributions concerning systematics and taxonomy, biogeography, biodiversity in order to describe abundance and distribution, as well as methodological development, are welcome. Submitted manuscripts will be considered for publication after peer review. There are no page charges for manuscripts accepted for publication.</p> Approaching the Arctic: the occurrence of Parin’s spinyfin Diretmichthys parini (Beryciformes: Diretmidae) in the Nordic Seas 2020-04-16T12:38:58+00:00 Arve Lynghammar Ingvar Byrkjedal Berit Margrete Bugjerde Rupert Wienerroither <p>Two adult specimens of the tropical to subtropical fish species <em>Diretmichthys parini</em> are reported from the North Sea and the northern Norwegian Sea, respectively. Both were accidentally caught as bycatch by commercial trawlers. Although not uncommon in Icelandic waters, it has not been documented from the Nordic Seas previously. In light of the major currents and water temperatures in the area, this is puzzling. Whether this pattern reflects a true distributional change or increased awareness and reporting from fishermen is not known.</p> 2020-04-03T00:00:00+00:00 Copyright (c) 2020 Arve Lynghammar, Ingvar Byrkjedal, Berit Margrete Bugjerde, Rupert Wienerroither Walleye pollock Gadus chalcogrammus Pallas, 1814 found north of Spitsbergen indicates a Pacific-Atlantic connection in the species 2020-10-16T12:27:02+00:00 Ingvar Byrkjedal Gunnar Langhelle <p>A small (36.5 cm) female walleye pollock <em>Gadus chalcogrammus</em> Pallas, 1814 was caught north of Spitsbergen in<br>2011. The specimen had a high number of pyloric caeca (n=109), indicating a Pacific origin. The record is the first<br>evidence of a possible input to the small Atlantic population of walleye pollock from the large populations on the<br>Pacific side.</p> 2020-10-16T00:00:00+00:00 Copyright (c) 2020 Ingvar Byrkjedal, Gunnar Langhelle The freshwater shrimp Gammarus lacustris (Malacostraca, Amphipoda) in lakes on the Hardangervidda mountain plateau, southern Norway: distribution and environmental requirements 2020-04-16T12:39:54+00:00 Tore Qvenild Trygve Hesthagen Arne Fjellheim <p>The distribution of the amphipod <em>Gammarus lacustris</em> on the Hardangervidda mountain plateau was mapped by&nbsp;screening published data from 245 lakes in 11 and 16 catchments in western and central/eastern areas, respectively.&nbsp;These data are primarily based on stomach analyses of brown trout <em>Salmo trutta</em>. In central/eastern areas, <em>G.&nbsp;lacustris</em> was recorded in 79% of all the lakes examined, while there are only two former records (4%) in the western&nbsp;area. The distribution pattern of <em>G. lacustris</em> on Hardangervidda appears to be related to environmental conditions.&nbsp;The apparent absence of <em>G. lacustris</em> in the western area may be explained by a combined effect of cold water due to&nbsp;higher deposits of snow and water with low ionic strength as a consequence of its bedrock of Precambrian gneisses&nbsp;and granites with little or no moraine cover. However, lakes in central/eastern areas sustain <em>G. lacustris</em> in spite of&nbsp;dilute water, as <em>G. lacustris</em> has been recorded in 89 lakes of which 28% had calcium concentration &lt;1.0 mg L<sup>-1</sup>, eight&nbsp;of them with pH &lt;6.0. The lower lethal threshold for calcium concentration seems to be ~0.5 mg L<sup>-1</sup>. <em>Gammarus&nbsp;lacustris</em> was found in lakes at altitudes of 832 to 1396 m a.s.l. Furthermore, their occurrence increased significantly&nbsp;with lake size, being 69% in lakes &lt;1.0 km<sup>2</sup> and 97% in larger lakes. The number of refugia with better water quality&nbsp;is likely to increase with lake size. <em>Gammarus lacustris</em> is highly searched for as prey by all size groups of brown&nbsp;trout (15-45 cm). Access to proximity refugia that reduce predation pressure from fish may also increase with lake&nbsp;size. Climate changes are now in progress in this mountain area, and detailed mapping of <em>G. lacustris</em> is important&nbsp;in order to trace future range changes.</p> 2020-03-16T00:00:00+00:00 Copyright (c) 2020 Tore Qvenild, Trygve Hesthagen, TH, Arne Fjellheim The viability of the crustacean Eurycercus lamellatus (Branchiopoda, Cladocera) in a high mountain area in southern Norway 2020-04-16T12:39:26+00:00 Tore Qvenild Trygve Hesthagen <p>The branchiopod <em>Eurycercus lamellatus</em> is widely distributed in Norwegian lakes, ranging from coastal to alpine areas. On the Hardangervidda mountain plateau in southern Norway, <em>E. lamellatus</em> was searched for in 144 lakes in 11 catchments in the western and 16 catchments in the central and eastern areas. Their occurrence is mainly based on the diet of brown trout <em>Salmo trutta</em>. <em>Eurycercus lamellatus </em>was recorded in 25% and 70% of the lakes in these two areas, respectively. This may be due to striking differences in the environmental conditions, with more dilute water and lower water temperatures in western areas, and hence shorter growing seasons. The occurrence of <em>E. lamellatus</em> in central and eastern catchments increased with lake size, being found in 65% and 85% of lakes with a surface area of &lt;2.0 and ≥2.0 km<sup>2</sup>, respectively. In the western area, <em>E. lamellatus</em> occurred less frequently in lakes above 1000 m a.s.l. That was not the case for lakes in central and eastern catchments. In this central part of Hardangervidda, the relative abundance of <em>E. lamellatus</em> in the diet of brown trout was obtained from five different lakes, showing that they were preyed upon throughout the growing season (June to October). When the two big crustaceans <em>Gammarus lacustris</em> and <em>Lepidurus arcticus</em> are at low densities in these lakes, <em>E. lamellatus</em> became the staple food item for brown trout, except for larger fish (&gt;400 mm). However, under high predation pressure, <em>E. lamellatus</em> also contributed significantly to the diet of larger fish. The abundance of <em>E. lamellatus</em> seems to vary highly on a yearly basis in one of the lakes (Sandvatn). Even though <em>E. lamellatus </em>is described as a typical littoral species, it was common down to depths of 15 m.</p> 2020-03-31T00:00:00+00:00 Copyright (c) 2020 Tore Qvenild, Trygve Hesthagen A review of grass flies (Diptera, Chloropidae) of Karelia and Murmansk Province of Russia 2020-07-02T11:57:46+00:00 Emilia Nartshuk Alexei Polevoi Andrey Przhiboro <p><span style="background-color: #ffffff;">One hundred and sixteen species of Chloropidae (Diptera) are recorded in Russian Karelia and Murmansk Province: 112 in Karelia and 44 in Murmansk Province. Twenty-two and seven species are new for Karelia and Murmansk Province, respectively. <em>Calamoncosis oscinella</em> is for the first time reported from Russia and <em>Elachiptera breviscutellata</em> - from European Russia. Pseudogaurax venustus is reinstated as <em>Gaurax venustus</em>. Taxonomic notes are provided on <em>Eribolus nana</em>, <em>Polyodaspis ruficornis</em>, <em>Oscinella vindicata</em> and <em>Cetema simile</em>. The distribution and biological data are given for every species. Point maps are provided for species with at least one exactly known location. The zoogeographical structure of Chloropidae fauna on the examined territories is briefly discussed and compared with other north-European countries.</span></p> 2020-07-02T00:00:00+00:00 Copyright (c) 2020 Emilia Nartshuk, Alexei Polevoi, Andrey Przhiboro Distribution, identification and range expansion of the common Asellidae in Northern Europe, featuring the first record of Proasellus meridianus in the Nordic countries 2020-08-12T12:13:20+00:00 Joanna Lynn Kemp Andreas Ballot Jens Petter Nilssen Ingvar Spikkeland Tor Erik Eriksen <p><span style="background-color: #ffffff;">Two out of the three common Asellidae species in Northern Europe are increasing their ranges, aided by human<br>activities. Here we report the discovery of <em>Proasellus coxalis</em> (Dollfuss 1892) in new areas in Norway and the<br>discovery of <em>Proasellus meridianus</em> (Racovitza 1919) for the first time in the Nordic countries, verified with<br>DNA barcoding. A new, detailed photo-identification guide to <em>Asellus aquaticus</em> Linnaeus 1758, <em>P. coxalis</em> and<br><em>P. meridianus</em> is presented. In addition to head pattern, attention is drawn to the female pleopods as an easy way to differentiate between the two genera. Then detailed examination of male pleopods 1 and 2 can differentiate between <em>P. coxalis</em> and <em>P. meridianus</em>. The origins, competitive relationships and potential dispersal mechanisms of the two introduced species and the native <em>A. aquaticus</em> are explored. By examining the shipping activity at the small, freshwater port where <em>P. meridianus</em> was found, we highlight the great connectivity between many European brackish and freshwater ports and possible pathways for species transfer. The risk of trans-oceanic freshwater to freshwater (not just brackish and saltwater) species transfer through ballast water needs to be better communicated. <em>Proasellus coxalis</em> may have been introduced to the river system of Lake Stokkalandsvatnet together with fish transported in microaquaria used as live bait for fishing.</span></p> 2020-08-12T00:00:00+00:00 Copyright (c) 2020 Joanna Lynn Kemp, Andreas Ballot, Jens Petter Nilssen, Ingvar Spikkeland, Tor Erik Eriksen Factors determining parasite abundance in European perch, Perca fluviatilis, European whitefish, Coregonus lavaretus, and Arctic charr, Salvelinus alpinus, in an oligotrophic lake, southern Norway 2020-08-18T12:16:18+00:00 Tom Robin Olk Ann-Cecilie Henriksen Solveig Irene Dolven Mathias Leithe Haukø Espen Lydersen Tor Atle Mo <p>Time and spatial variations in macroparasite status were investigated in European perch, <em>Perca fluviatilis</em>, European whitefish, <em>Coregonus lavaretus</em>, and Arctic charr, <em>Salvelinus alpinus</em> in Lake Norsjø (Southern Norway), based on gillnet fishing in three locations in the spring, summer, and fall 2018. In addition, length, weigth, age, sex, δ<sup>13</sup>C, and δ<sup>15</sup>N were determined. Parasite abundance was modelled using negative binomial generalized linear models in relation to fish metrics, season, and sampling location. The most prevalent parasite species were determined by the diet and habitat of the host. European perch was mainly infected by acanthocephalans, European whitefish mainly infected by acanthocephalans and cestodes, and Arctic charr mainly infected by cestodes. The most prevalent parasites in European perch are transmitted by benthic animals. Parasites in European whitefish are transmitted by both benthic animals and copepods, while the most prevalent parasites in Arctic charr are copepod transmitted. This corresponds well with the δ<sup>13</sup>C signatures in the three species, indicating that European perch primarily fed in the littoral zone (δ<sup>13</sup>C: -24.9 ± 2.5 ‰), Arctic charr in the pelagic and profundal zone (δ<sup>13</sup>C: -29.4 ± 1.1 ‰), while European whitefish both fed in the littoral and pelagic zone (δ<sup>13</sup>C: -28.3 ± 2.3 ‰) of Lake Norsjø. Individual abundances of parasites depended on host age, length, sex, δ<sup>15</sup>N, and season. Positive correlations between parasite abundance and host age, length, or trophic level measured as δ<sup>15</sup>N were most common, and occurred in all three host species. Many parasites accumulate with age, and larger hosts provide more diverse habitats for parasites.</p> 2020-08-18T00:00:00+00:00 Copyright (c) 2020 Tom Robin Olk, Ann-Cecilie Henriksen, Solveig Irene Dolven, Mathias Leithe Haukø, Espen Lydersen, Tor Atle Mo The invasive amphipod Gammarus tigrinus Sexton, 1939 conquering the north of Europe using a new pathway: the first recordings from Norway 2020-09-09T12:17:49+00:00 Ingvar Spikkeland Jørn Bøhmer Olsen Ragnar Kasbo Kjell Magne Olsen Jens Petter Nilssen <p>The invasive amphipod <em>Gammarus tigrinus</em> has during the last decades spread to large parts of Northern Europe, mainly using pathways eastwards from The British Isles to Continental Europe and further northeast into the Baltic Sea. From the coastline it has to some extent spread further inland, especially in topographically low-relief landscapes with highly polluted rivers. This account reports another geographical direction of dispersal, towards north into Southern Norway. In coastal brackish-water regions <em>G. tigrinus</em> may displace other gammarids. Large parts of Norway consist of high-relief landscapes close to many estuaries, so the further spread into this country is doubtful. However, if the taxon can avoid the initial barriers using vectors and spread into new watercourses above such barriers and thrive in this new ambient water chemistry, it may have large negative influence on the other benthic fauna. But Norwegian lakes and rivers are most probably too electrolyte-poor to support this species. However, in estuaries and other brackish waters along the coast, at least in the southern part of Norway, the species will thrive. <em>Gammarus tigrinus</em> is the only known intermediate host for the native American acanthocephalan parasite <em>Paratenuisentis ambiguus</em>, which has the American eel as its main host. This parasite also infects the European eel, and this poses an additional threat to the already endangered eel in Norwegian rivers where <em>G. tigrinus</em> has been recorded.</p> 2020-09-09T00:00:00+00:00 Copyright (c) 2020 Ingvar Spikkeland, Jørn Bøhmer Olsen, Ragnar Kasbo, Kjell Magne Olsen, Jens Petter Nilssen