Ornis SvecicaPub Date : 2024-08-08DOI: 10.34080/os.v34.25271
Elsie Kjeller, Jonas Waldenström, Johan Elmberg, G. Gunnarsson
{"title":"Herbivory on aquatic macrophytes by geese and swans—a review of methods, effects, and management","authors":"Elsie Kjeller, Jonas Waldenström, Johan Elmberg, G. Gunnarsson","doi":"10.34080/os.v34.25271","DOIUrl":"https://doi.org/10.34080/os.v34.25271","url":null,"abstract":"In recent decades, interest has grown in how increasing populations of herbivorous geese and swans (Anseriformes: Anatidae: Anserinae) affect macrophyte communities in wetlands, especially because many waterbodies are simultaneously subjected to stressors like eutrophication and biodiversity declines. Here, we review the literature on methods applied in grazing experiments that have been conducted in aquatic ecosystems. We also investigate and how different macrophyte characteristics may respond to waterfowl herbivory. Results indicate that both research methodology and responses of macrophytes differ widely among studies. While most experimental studies on grazing pressure employ a ‘paired plot design’ with exclosures and open control plots, the structure, size, and placement of plots vary among studies. Commonly sampled macrophyte variables are biomass (of either above- or below-ground plant parts), density, height, plant cover, and community composition. The literature provides support that geese and swans significantly affect several of these variables, but the outcome depends on additional factors, e.g., waterfowl density, water depth, and timing (within or between seasons/years). Because of the persisting conservation threats to aquatic ecosystems, more knowledge is needed about potential direct and indirect consequences of waterfowl herbivory in these environments.","PeriodicalId":52418,"journal":{"name":"Ornis Svecica","volume":"77 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141926655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ornis SvecicaPub Date : 2024-07-26DOI: 10.34080/os.v34.25715
Adriaan De Jong, O. Kleven, Johanna Honka, Isak Vahlström
{"title":"DNA profiles of shed Taiga Bean Goose feathers indicate between-season fidelity to moulting sites in Swedish Lapland","authors":"Adriaan De Jong, O. Kleven, Johanna Honka, Isak Vahlström","doi":"10.34080/os.v34.25715","DOIUrl":"https://doi.org/10.34080/os.v34.25715","url":null,"abstract":"Recently, the Taiga Bean Goose Anser f. fabalis breeding population of Southern Lapland, Sweden, was shown to use a network of local sites during their summer wing moult. We used microsatellite markers to identify individual geese from DNA in shed feathers collected in 2016–2020 on six sites, enabling us to identify 168 unique individuals from 178 fully genotyped feathers. Nine individuals were represented multiple times among the collected feathers. All controls of identified individuals were made on the original site, never on an alternative site. Our results suggest a significant level of site fidelity and, thus, the need to provide a stable, low-disturbance network of moulting sites for the Southern Lapland sub-population of this endangered taxon.","PeriodicalId":52418,"journal":{"name":"Ornis Svecica","volume":"16 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141801472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ornis SvecicaPub Date : 2024-07-26DOI: 10.34080/os.v34.23510
Börje Dahlén, Ute Bradter, Elisabet Ottosson, Mats OG Eriksson
{"title":"Influence of pool habitat characteristics on Red-throated Loon Gavia stellata occupancy and reproduction in a Boreal forest landscape","authors":"Börje Dahlén, Ute Bradter, Elisabet Ottosson, Mats OG Eriksson","doi":"10.34080/os.v34.23510","DOIUrl":"https://doi.org/10.34080/os.v34.23510","url":null,"abstract":"We investigated the occupancy of alternative breeding pools for Red-throated Loon Gavia stellata and the reproductive output in relation to a selection of habitat characteristics in a coniferous forest inland area in South-central Sweden, using generalized linear mixed models. Models provided good support for the conclusion that small-sized pools with high coverage of floating vegetation were preferred. The survival of pre-fledged chicks was higher when foraging waters were located closer, and open mires around the breeding pool were more extensive. We propose that these habitat characteristics should be considered in nature conservation planning and management, as well as in environmental impact assessments. We found that with the current data, predicting pool occupancy and chick survival based on the selected habitat characteristics was not sufficiently accurate to replace field surveys and can only be used as a complementary method. We also emphasize the importance of freshwaters, potentially to be used for foraging in the surrounding landscape, which is an often-overlooked aspect in management and impact assessments.","PeriodicalId":52418,"journal":{"name":"Ornis Svecica","volume":"121 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141801813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ornis SvecicaPub Date : 2024-06-10DOI: 10.34080/os.v34.24041
Fredrik Andreasson
{"title":"Two Eurasian Blue Tits Cyanistes caeruleus roosting together in a nest-box on multiple winter nights","authors":"Fredrik Andreasson","doi":"10.34080/os.v34.24041","DOIUrl":"https://doi.org/10.34080/os.v34.24041","url":null,"abstract":"Birds that spend\u0000the winter in a harsh and cold climate face a suite of challenges that require optimization of energy expenditure and energy intake. Some birds roost communally, which can increase energy savings during cold winter nights. However, this behaviour is almost completely absent in chickadees, tits, and titmice (Paridae) as there are very few accounts in the literature of parids roosting together. Here I review these accounts and describe an observation where two Eurasian Blue Tits Cyanistes caeruleus were found roosting together in a nest-box on multiple winter nights in January of 2021.","PeriodicalId":52418,"journal":{"name":"Ornis Svecica","volume":"121 47","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141362739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ornis SvecicaPub Date : 2024-06-03DOI: 10.34080/os.v34.22262
Jonas Engzell
{"title":"Territory occupation sequence and population change 2005–2019 in a satellite versus core area for Grasshopper Warblers Locustella naevia","authors":"Jonas Engzell","doi":"10.34080/os.v34.22262","DOIUrl":"https://doi.org/10.34080/os.v34.22262","url":null,"abstract":"Because of habitat preferences and variation at a landscape level, a species’ distribution tends to show a level of aggregation. In the Grasshopper Warbler Locustella naevia, the distribution is linked to suitable breeding habitats of open grassy and herbaceous grounds, often adjacent to water. Consequently, the presence of the Grasshopper Warbler at landscape level will consist of core and satellite areas. In theory, birds can sense habitat quality and should occupy territories within those areas based on territory quality. It might also result in different population trends between different areas in the landscape. I tested these assumptions through a 15-year study in a satellite area, comparing the results to a nearby core area. In both areas, the males occupy a territory based on the perceived attractiveness, and general patterns of the territory utilization were similar between areas. Territory density was lower and the males arrived later in the satellite area, thereby confirming the satellite/core area relationship between the study areas. In the core area, no significant change in population size was noted, while in the satellite area, the population decreased significantly.","PeriodicalId":52418,"journal":{"name":"Ornis Svecica","volume":"57 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141272327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ornis SvecicaPub Date : 2024-05-14DOI: 10.34080/os.v34.23901
Björn Ferry, Johan Ekenstedt, Martin Green
{"title":"Densities of Eurasian Three-toed Woodpecker Picoides tridactylus and sap trees correlate across a latitudinal gradient in Sweden","authors":"Björn Ferry, Johan Ekenstedt, Martin Green","doi":"10.34080/os.v34.23901","DOIUrl":"https://doi.org/10.34080/os.v34.23901","url":null,"abstract":"Mapping of sap rows on trees has been proposed to detect the easily overlooked Eurasian Three-toed Woodpecker Picoides tridactylus in boreal forests. Sap rows have a distinct appearance that can be detected in the bark for many years. While it is well-established that Eurasian Three-toed Woodpeckers make sap rows on coniferous trees, it is uncertain whether they also make sap rows on deciduous trees, such as birches (Betula sp.), or if these are made by other woodpecker species. We collated data on woodpecker abundance from the Swedish Bird Survey’s fixed route monitoring scheme and correlated this with data on sap tree abundance from systematic searches in three different parts of Sweden. Assuming that species-specific woodpecker behaviours are similar across Sweden, we suggest that Eurasian Three-toed Woodpeckers are responsible for the majority of sap rows on birches in the central and northern parts of Sweden, while Great Spotted Woodpeckers Dendrocopos major made the few sap rows found in southern Sweden and likely some of those further north. With that caveat in mind, our findings might be used to develop a more efficient method of mapping Eurasian Three-toed Woodpecker abundance in Sweden.","PeriodicalId":52418,"journal":{"name":"Ornis Svecica","volume":"22 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140981668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ornis SvecicaPub Date : 2024-05-08DOI: 10.34080/os.v34.25148
Reino Andersson
{"title":"Färgvariation hos vattenpiplärka Anthus spinoletta i vinterdräkt","authors":"Reino Andersson","doi":"10.34080/os.v34.25148","DOIUrl":"https://doi.org/10.34080/os.v34.25148","url":null,"abstract":"This study of colour variation on Water Pipit Anthus spinoletta in winter plumage, is based on photos of 93 individuals from southern Sweden. Using moulting criteria, the birds were aged from the photographs, and the presence or absence of five specific plumage characteristics were recorded. Twelve individuals in this study confirm the hypothesis that adult Water Pipits show a distinct combination of plumage traits during winter. However, the presence of these plumage traits varied in younger birds in their first winter plumage. Among the 81 individuals classified as first winter plumage, 23 (28%) displayed all “adult characteristics”, 32 (40%) one to four of the characteristics, while 26 (32%) lacked all “adult characteristics”. The latter group thus lacked a gray nape/crown, whitish supercilium, and lighter brown colouration of the mantle/scapulars. Ever since the first Swedish records in the mid-1990s, there have been ongoing discussions regarding species-specific characters in Water Pipits. The present quantification of colour variation in different age groups complements previous criteria for a reliable species identification of Water Pipits in winter plumage.","PeriodicalId":52418,"journal":{"name":"Ornis Svecica","volume":"18 11","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141001486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ornis SvecicaPub Date : 2024-03-26DOI: 10.34080/os.v34.26122
Hans Ryttman
{"title":"The influence of climate change on brood size and breeding time in three tit species in Sweden, 1962–2019","authors":"Hans Ryttman","doi":"10.34080/os.v34.26122","DOIUrl":"https://doi.org/10.34080/os.v34.26122","url":null,"abstract":"Climate change is expected to affect many biological systems, including the timing of seasonal events such as breeding in birds. In this study, I investigated how brood size and timing of reproduction (measured as median date for ringing of broods) changed for three tit species in Sweden 1962–2019 using data reported to the Swedish Bird Ringing Centre. The brood size for the Coal Tit Periparus ater increased from 7.74 between 1962–2001 to 7.98 young between 2002–2019, while no change was detected for Crested Tit Lophophanes cristatus or Willow Tit Poecile montanus. The largest biological effects were seen for timing of reproduction, with Coal Tits and the Crested Tits initiating breeding about seven days earlier at the end of the study period compared to the 1960s. The Willow Tit data also suggested earlier breeding, but only by about two days across the study period.","PeriodicalId":52418,"journal":{"name":"Ornis Svecica","volume":"102 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140381117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ornis SvecicaPub Date : 2024-03-08DOI: 10.34080/os.v34.23521
Thomas Holmberg
{"title":"Pärlugglans Aegolius funereus häckningsekologi i en jämtländsk population 1976–1985","authors":"Thomas Holmberg","doi":"10.34080/os.v34.23521","DOIUrl":"https://doi.org/10.34080/os.v34.23521","url":null,"abstract":"A long-term Boreal Owl Aegolius funereus nest box project ran 1976–1985 in central Sweden. Average occupancy among 200 nest boxes was 16% (range 0–54%) with average clutch size 6.0 eggs and number of fledged per successful breeding 4.6, while 41% of breeding attempts failed, primarily due to predation by pine marten Martes martes or desertion by the female. The highest observed breeding density was 0.9 breedings/km2. Five cases of bigamy were observed. Females weighed 50% more than males during egg laying and incubation, probably because of pre-emptive weight gain to compensate for the risk of subsequent changes to food availability. The male provisioned both the female and chicks for most of the breeding period, mainly with small rodents (87%). Population sizes of small rodents fluctuated in 3–4-year cycles. Reproduction was successful during phases of increasing rodent density (1977–1978, 1980–1981, and 1984–1985), while almost no breedings were initiated during nadir years (1976, 1979, and 1982–1983). Ringing recoveries suggested that juveniles recruited into the local population in years with abundant food resources, but dispersed if food availability was declining. Adult females were often nomadic, while most males were resident.","PeriodicalId":52418,"journal":{"name":"Ornis Svecica","volume":"29 11","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140257682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}