Polar Biology最新文献

{"title":"DNA metabarcoding reveals high diversity of fish and macrofaunal species in diets of little auks and other Arctic seabird species in Svalbard","authors":"Joep J. de Leeuw, Xantia van den Brink, Geir W. Gabrielsen, Reindert Nijland","doi":"10.1007/s00300-024-03276-3","DOIUrl":"https://doi.org/10.1007/s00300-024-03276-3","url":null,"abstract":"<p>Climate change is a major concern for the future of marine Arctic food webs. Diet shifts of seabirds can be used as indicators of environmental changes such as species compositions of food webs. However, studies on diets are often laborious and costly, while research in vulnerable Arctic environments benefits from short visits for data collection that minimize disturbance to Arctic wildlife and the environment. DNA-metabarcoding techniques are rapidly developing and could be used as an effective method of monitoring diet choice of seabirds. We tested DNA-metabarcoding on seabird faeces collected during short visits of typically around 30 min at breeding colonies of black-legged kittiwake <i>Rissa tridactyla</i> (3 colonies), Brünnich’s guillemot <i>Uria lomvia</i> (2 colonies) and little auk <i>Alle alle</i> (3 colonies). DNA metabarcoding based on COI and 18S of a limited number of faeces samples revealed a wide spectrum of fish species and crustaceans in the diets of these species, comparable with or even exceeding diversity in diet composition found in conventional, more invasive techniques where birds are shot or caught and handled to obtain samples. While previous studies on diet choice of little auk, a crustacean specialist, mainly report small fractions of unidentified fish remains, DNA metabarcoding of faeces revealed a large variety of pelagic and benthic fish species supplementing its diet. We conclude that DNA metabarcoding of seabird faeces can be an effective attribute to diet studies supporting our understanding of changes in numbers and distribution of Arctic seabirds and their marine environment.</p>","PeriodicalId":20362,"journal":{"name":"Polar Biology","volume":"35 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141572169","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diversity and functionality of soil prokaryotic communities in antarctic volcanic soils: insights from penguin-influenced environments","authors":"Diego Segura, Karen Jordaan, Beatriz Díez, Javier Tamayo-Leiva, Sebastian Doetterl, Daniel Wasner, Jerónimo Cifuentes-Anticevic, Angélica Casanova-Katny","doi":"10.1007/s00300-024-03273-6","DOIUrl":"https://doi.org/10.1007/s00300-024-03273-6","url":null,"abstract":"<p>In the nutrient-limited Antarctic terrestrial habitat, penguins transfer a significant amount of nutrients from the marine to the terrestrial ecosystem through their depositions (i.e., guano). This guano influences soil physicochemical properties, leading to the formation of ornithogenic soil rich in nutrients and organic matter. We hypothesize that soil prokaryotic communities will be strongly influenced by the contribution of nitrogenous nutrients from penguin rookeries, maintaining the influence over long distances. The objective was to establish how the soil prokaryotic diversity and community structure change with distance from a penguin colony, which provides large amounts of guano and nitrogenous compounds, and to study the effects of these nutrients on the functional role of these communities. Methods include volcanic soil sampling along a 1200 m transect from the penguin active rookery and the characterization of soil nutrient content and soil prokaryotic communities using 16S rRNA high-throughput amplicon sequencing. In contrast to our hypothesis, the results showed that the impact of guano from the penguin colony was restricted to the first 300 m. Probably because the penguin rookery was sheltered, strong wind and wind direction did not affect the transport of nutrients from the penguin rookery. Areas close to the penguin rookery were dominated by <i>Proteobacteria</i> and <i>Bacteroidetes</i>, while areas situated further away were dominated by <i>Acidobacteria</i>, <i>Actinobacteria</i>, <i>Chloroflexi</i>, <i>Gemmatimonadetes</i>, <i>Nitrospirae</i>, and <i>Planctomycetes</i>. Beta diversity analysis among the soil prokaryotic communities revealed a high degree of community heterogeneity, strongly associated with N compound characteristics (NH₄, NO₃, and %N), C, and pH. Inferences from N metabolism genes suggest a high potential of the microbial community for dissimilatory nitrate reduction genes (DNRA) to ammonium, assimilatory nitrate reduction (ANR), and denitrification. Although it is assumed that the nitrogenous compounds of the penguin colonies reach long distances and affect the prokaryotic community, this effect can vary with wind directions or the morphology of the site, reducing the impact of the guano over long distances, as our results indicate. On the other hand, functional predictions give some clues about the main actors in nitrogen cycling, through processes like dissimilatory nitrate reduction, assimilatory nitrate reduction, and denitrification.</p>","PeriodicalId":20362,"journal":{"name":"Polar Biology","volume":"24 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141550185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Trends in Arctic-nesting loon (Gavia spp.) populations in North America","authors":"Ingrid L. Pollet, Sarah E. Gutowsky, Ray T. Alisauskas, William Harvey, Dana K. Kellett, Kristen M. Lalla, Josée Lefebvre, Jake Russell-Mercier, Jennifer F. Provencher, Emily D. Silverman, Paul A. Smith, Mark L. Mallory","doi":"10.1007/s00300-024-03277-2","DOIUrl":"https://doi.org/10.1007/s00300-024-03277-2","url":null,"abstract":"<p>Several species of loons (or divers; Gaviidae) breed in Arctic Canada, and concern has been raised about their changes in abundance in light of threats such as bycatch and at-sea industrial development. These loons are not well monitored, but we gathered localized count data for three Arctic-nesting loons (Pacific loon <i>Gavia pacifica</i>, red-throated loon <i>G. stellata</i>, and yellow-billed loon <i>G. adamsii</i>) from multiple sources and estimated mean annual population change to estimate species-specific trends over varying time periods. Most breeding ground information between 1996 and 2022 suggested stable numbers for each species, although data were scarce for yellow-billed loon. Trends during the non-breeding season from 1966 to 2021 were estimated for red-throated and Pacific loons from the Christmas Bird Count, a citizen science general bird count, and suggested overall stable or increasing numbers, despite some substantial regional differences. Again, yellow-billed loon numbers were not captured well during the non-breeding season. Aerial winter waterfowl surveys on the east coast of North America (2008–2011, 2014) showed positive trends for red-throated loons for most locations north of 38° latitude and stable trends elsewhere. The paucity of both breeding and non-breeding count data for yellow-billed loons is unfortunate, as this species is found in high numbers in fishing gear in the Arctic. Overall, the limited available data do not suggest that loon populations breeding in the Canadian Arctic have experienced extensive declines, but monitoring of yellow-billed loons should be a priority.</p>","PeriodicalId":20362,"journal":{"name":"Polar Biology","volume":"30 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141522049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Consumption of Antarctic krill Euphausia superba by mackerel icefish, Champsocephalus gunnari off the South Orkney Islands: filling an information gap in the current ecosystem-based management approach","authors":"J. A. Canseco, N. Alegría, E. J. Niklitschek","doi":"10.1007/s00300-024-03270-9","DOIUrl":"https://doi.org/10.1007/s00300-024-03270-9","url":null,"abstract":"<p>The Antarctic marine ecosystem is largely dominated by <i>Euphausia superba,</i> the most abundant krill species consumed by a wide array of predators, including whales, penguins, flying birds, seals, fish and cephalopods. The current management of the krill fishery follows an ecosystem-based approach which takes into account the distribution, abundance of <i>E. superba</i> and its main predators plus their interactions. Mackerel icefish, <i>Champsocephalus gunnari,</i> was once considered the most abundant meso-pelagic fish species and a very important consumer of <i>E. superba</i> until its population was collapsed by overfishing in the early 90s. Currently, <i>C. gunnari</i> populations are slowly recovering which may increase predation on <i>E. superba</i>. Therefore, in this study, we analyze the distribution and density of <i>E. superba</i> and <i>C. gunnari</i>, gain some insights about the type of foraging strategy of <i>C. gunnari</i> and estimate its consumption of <i>E. superba</i> under three different biomass scenarios of <i>C. gunnari</i>: 7000 (<i>B</i>_t), 70,000 (<i>B</i>_50%) and 140,000 (<i>B</i>₀) t. We focus particularly on the potential area of overlap between <i>C. gunnari</i> and Adélie penguin (<i>Pygoscelis adeliae</i>) off the South Orkney islands. Bayesian geostatistical models were employed to test whether <i>C. gunnari</i> followed an ideal or generalized ideal-free distribution. Spatially explicit consumption estimates were derived under the scenarios of 7000 (<i>B</i>_t), 70,000 (<i>B</i>_50%) and 140,000 (<i>B</i>₀) t of <i>C. gunnari</i> biomass. We found that both species exhibit a higher probability of presence and density north of the South Orkney Islands, where they present a high overlap. The probability of presence of <i>Champsocephalus gunnari</i> was best explained by the ideal-free distribution whereas its acoustic density was best explained by an independent spatial model, showing no relation to the distribution of <i>E. superba</i>. Individual consumption of <i>E. supeba</i> by <i>C. gunnari</i> was estimated to be 153.5 ± 77.9 g ind⁻¹. Thus, current biomass (<i>B</i>_t) would only remove ~ 0.07% of <i>E. superba</i> biomass in the focus area. Under a pre-exploitation biomass level (<i>B</i>₀), <i>C. gunnari</i> would remove ~ 1.4% of <i>E. superba</i> biomass. This study provides novel insights into the relationship between a key species like <i>E. superba</i> and a highly specialized consumer such as <i>C. gunnari</i> around the South Orkney Islands and contributes to fill in an important gap regarding fish consumption of krill in the Antarctic ecosystem.</p>","PeriodicalId":20362,"journal":{"name":"Polar Biology","volume":"58 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141529307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Population structure of the bivalve Aequiyoldia eightsii (Jay, 1839) in the shallow water zone of Admiralty Bay (King George Island, Antarctic Peninsula)","authors":"Isabella B. Alcântara, Adriana G. Dalto, Helena P. Lavrado","doi":"10.1007/s00300-024-03268-3","DOIUrl":"https://doi.org/10.1007/s00300-024-03268-3","url":null,"abstract":"<p>The protobranch <i>Aequiyoldia eightsii</i> is one of the most common bivalves in Antarctica and for the first time, its population structure was studied in Admiralty Bay, an Antarctic Specially Managed Area (ASMA), to establish a baseline for future monitoring. Density, size structure, length–weight relationship, condition index, and shell morphometry were evaluated at the shallow coastal zone of the bay. High abundance values of <i>A. eightsii</i> were related to sites with greater contributions of mud particles and total organic carbon contents in the sediment, while the condition indexes were higher in Martel Inlet, possibly due to higher food availability. Individuals obtained from gravel-rich sediments were significantly larger than compressed, while rounded forms were observed in sandy and muddy bottoms of the bay. Positive allometric growth was reported in most sites, except Botany Point, where specimens presented an isometric growth. The results demonstrated that the sediment composition and its organic content influence the population structure of <i>A. eightsii</i> as well as biological factors such as predation and recruitment rates. It is also worth noting that the phenotypic shell variability observed for this protobranch species in geographically close sites (hundreds of meters) highlights the importance of local-scale heterogeneity to be considered in future monitoring programmes for Antarctic marine ecosystems.</p>","PeriodicalId":20362,"journal":{"name":"Polar Biology","volume":"344 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141505718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Feasibility and knowledge gaps to modeling circumpolar seabird bycatch in the Arctic","authors":"Ingrid L. Pollet, Yuri Artukhin, Signe Christensen-Dalsgaard, Erpur Hansen, Kathy J. Kuletz, Flemming Ravn Merkel, Guðjón Már Sigurðsson, Hallvard Strøm, Jennifer F. Provencher, Mark L. Mallory","doi":"10.1007/s00300-024-03272-7","DOIUrl":"https://doi.org/10.1007/s00300-024-03272-7","url":null,"abstract":"<p>Alteration and diminution in sea ice cover in the Arctic region will give rise to an intensification and expansion of fishing activities in the Arctic and associated marginal seas. Increased fishing activity, especially in the summer, could pose a direct threat to the millions of seabirds breeding in this region, as well as non-breeding migrants, and potentially result in an increase of bycatch mortality. To inform what conservation and management actions may be needed, an analysis of where seabirds/fisheries interaction are most likely to occur is required. Here, we establish what information would be required to effectively model circumpolar bycatch risk of seabirds in the Arctic, and then we assess the availability of the requisite data. The quality and availability of fishing effort, and bycatch monitoring effort data are not homogeneous among Arctic countries. Undertaking a true circumpolar analysis at this time would be difficult, and with the current data accessibility, many assumptions would have to be made, potentially leading to caveats in the results. Improved communications between the various agencies and institutes working on fisheries and seabirds would strengthen the quantitative basis for future analyses. We offer suggestions on how to improve bycatch estimates and the identification of high-risk areas for seabird bycatch in the Arctic.</p>","PeriodicalId":20362,"journal":{"name":"Polar Biology","volume":"46 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141505719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aquatic bird predation by antarctic and subantarctic pinnipeds vagrants off argentina","authors":"Antonella D. Padula, M. Alejandra Romero, Rodrigo Machado, Alan F. Rosenthal, Mariela Dassis, Diego H. Rodríguez, Caio J. Carlos, Juan Pablo Seco Pon, Pablo Denuncio","doi":"10.1007/s00300-024-03271-8","DOIUrl":"https://doi.org/10.1007/s00300-024-03271-8","url":null,"abstract":"<p>Antarctic and Sub-Antarctic pinnipeds are well-known seasonal visitors of the Southwest Atlantic Ocean. According to the literature, at their breeding grounds, they feed mainly on a variety of fish, cephalopods, and crustaceans. During the non-breeding period and far away from its breeding colonies, little is known about their feeding habits. Here, we present records of predation on aquatic birds by Antarctic and Sub-Antarctic pinnipeds off northern Argentinian coast (37°27′ S, 57°06′ W to 41°50' S 65°02' W). We examined the gastrointestinal contents of 22 specimens of three pinnipeds species (<i>Arctocephalus gazella</i> [n = 10], <i>A. tropicalis</i> [n = 11] and <i>Hydrurga leptonyx</i> [n = 1]) collected from 1996 to 2023. Aquatic birds remains were found in the gastrointestinal tracts of three individuals (13.64%): two <i>A. gazella</i> and one <i>H. leptonyx</i>. We identified feathers, and other bird parts by comparing them to specimens from scientific collections and descriptions/illustrations from the literature. Two of the three aquatic birds found in the gastrointestinal tracts were most probably Magellanic Penguins (<i>Spheniscus magellanicus</i>), whereas the other one was a Great grebe (<i>Podiceps major</i>). To our knowledge, this is the first study reporting predation on aquatic birds by Antarctic pinnipeds far from their breeding colonies.</p>","PeriodicalId":20362,"journal":{"name":"Polar Biology","volume":"26 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141505720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reindeer (Rangifer tarandus) hindlimb joint kinetics: propulsive and energy storage mechanisms and mechanical work","authors":"Guoyu Li, Rui Zhang, Hao Pang, Junfeng Wang, Dan Jin, Xumin Sun, Dianlei Han, Zhisong Li, Lige Wen","doi":"10.1007/s00300-024-03265-6","DOIUrl":"https://doi.org/10.1007/s00300-024-03265-6","url":null,"abstract":"<p>As seasonal migratory animals, reindeer inhabit the natural habitats in Arctic regions and have evolved their hindlimb joints to adapt to the complex ground conditions there. Inverse dynamics of the joints is an important tool to study foot functions. Herein, with a motion tracking system and plantar pressure data based on kinematics and inverse dynamics of hindlimbs, we investigated the changes in joint angles, net joint moments, net joint powers, and work of reindeer at different speeds. Reindeer may adopt different movement patterns to efficiently utilize energy and adapt to the demands of different gaits and speeds. The joint ranges of motion (ROM) of the ankle joint (<i>α</i>_b), metatarsophalangeal (MTP) joint (<i>α</i>_c), and interphalangeal joint (<i>α</i>_d) of the hindlimbs were about 20.73°–28.87°, 40.37°–47.69°, and 24.47°–26.18°, respectively. The ankle joint produced positive work to provide propulsion. The positive work done at the ankle joint during walking, slow trotting, and fast trotting was 8.61 × 10^–2, 9.25 × 10^–2, and 15.44 × 10^–2 J·kg⁻¹, respectively. The MTP and interphalangeal joints both absorbed energy during walking, slow trotting, and fast trotting. The energy absorption at the respective speeds was 12.53 × 10^–2, 13.57 × 10^–2, and 19.90 × 10^–2 J·kg⁻¹, respectively, by the MTP joint and was 9.49 × 10^–2, 7.71 × 10^–2, and 10.26 × 10^–2 J·kg⁻¹, respectively, by the interphalangeal joint. The MTP joint and interphalangeal joint of the hindlimbs serve as the primary sites for energy storage and release, functioning as an elastic system. This study contributes to a deeper understanding about the biomechanical properties of hindlimb joints and provides a theoretical basis for designing extremity robots in extreme environments through analyzing the functional characteristics of reindeer foot joints.</p>","PeriodicalId":20362,"journal":{"name":"Polar Biology","volume":"4 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141173459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Water mass influence on spatial and seasonal distributions of diatoms, dinoflagellates and coccolithophores in the western Barents Sea","authors":"Qingshan Luan, Elaine Mitchell, Sian F. Henley, Andrew C. M. Orkney, Heather A. Bouman, Judith S. Braun, Alex J. Poulton, Keith Davidson","doi":"10.1007/s00300-024-03255-8","DOIUrl":"https://doi.org/10.1007/s00300-024-03255-8","url":null,"abstract":"<p>Arctic phytoplankton are highly sensitive to seawater physical and chemical conditions, especially in the context of rapid climate change and sea ice loss. We studied the spatial and seasonal distributions of diatoms, dinoflagellates and coccolithophores, and clarified their associations with light, temperature and nutrients in the western Barents Sea in late summer 2017, and winter, spring and early summer 2018. Diatoms, composed mainly of <i>Chaetoceros</i>, <i>Fragilariopsis</i> and <i>Thalassiosira</i>, bloomed in spring at the southern border of the marginal ice zone with mean abundance of 1.1 × 10⁶ cells L⁻¹ and biomass of 119.5 µg C L⁻¹, and were observed to follow the retreat of sea ice in the Arctic water to the north at the shelf break near Nansen Basin, contributing to the progression of the summer situation. Dinoflagellates flourished in surface waters south of Svalbard in summer, with maxima of 2.2 × 10⁵ cells L⁻¹ and 78.2 µg C L⁻¹. High abundances and calcite mass of coccolithophores were detected in the southern Barents Sea and southwest of Svalbard in summer, with maxima of 3.3 × 10⁵ cells L⁻¹ and 4.7 µg C L⁻¹. Two distinct phytoplankton assemblages, closely linked with Atlantic water and Arctic water, were geographically separated by the Polar Front in two summers, with a percent similarity below 11.9%, suggesting great influence of the two water masses on large-scale distributions of phytoplankton. Redundancy analysis revealed that temperature was one of the most important factors in shaping the seasonal distributions of diatoms, while irradiance showed positive correlation with dominant dinoflagellates of each season. From the perspectives of phytoplankton composition and carbon biomass, our findings highlight the governing effect of physical seawater conditions on driving seasonal patterns of phytoplankton biogeography, as well as the pivotal role of nutrients in supporting the phytoplankton growing seasons in the western Barents Sea.</p>","PeriodicalId":20362,"journal":{"name":"Polar Biology","volume":"506 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141150231","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mysis segerstralei, an unexpected but important prey for resident Arctic charr (Salvelinus alpinus) in a Svalbard lake","authors":"Martin-A. Svenning, Ole Christian Skogstad, Øyvind Skogstad, Reidar Borgstrøm","doi":"10.1007/s00300-024-03261-w","DOIUrl":"https://doi.org/10.1007/s00300-024-03261-w","url":null,"abstract":"<p><i>Mysis segerstralei</i> is distributed over a wide geographic area and in habitats with a variety of salinity conditions, including marine and brackish waters around Svalbard. The species has seldom been found in freshwater lakes, and the discovery of <i>M. segerstralei</i> in Lake Pulmankijärvi at the border between Northeastern Norway and Finland, may represent the single known freshwater occurrences in western Europe. Svalbard lake systems are characterized by very low water temperatures, long-term ice cover, and low levels of nutrients. Food is thus limited, and chironomids generally dominate the stomach contents in Arctic charr, the only freshwater fish species on Svalbard. Based on several surveys in more than 30 of Svalbard lakes over many decades, <i>M. segerstralei</i> has only been found as food for Arctic charr in Lake Vårfluesjøen. In a later fishery survey, we studied the diet of Arctic charr in this lake. The stomach contents from Arctic charr sampled in the profundal habitats were dominated by <i>M. segerstralei</i>, but the species was also among the most frequent prey items in the littoral and pelagic habitats. This unexpected occurrence of <i>M. segerstralei</i> demonstrates the high importance of mysids even in a low-productive, High Arctic lake.</p>","PeriodicalId":20362,"journal":{"name":"Polar Biology","volume":"35 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141173424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}