Restoring wetland biodiversity using research : Whole-community facilitation by beaver as framework

Wetlands are declining worldwide, and there is a great need for their restoration and creation. One natural agent of wetland engineering is beavers,Castorspp., which have returned or are returning to many parts of their former range. We initially studied the facilitative effect of the beaverCastor canadensison a waterbird community consisting of three waders and four ducks in boreal wetlands in southern Finland. Both waterbird species diversity and abundance increased when beavers impounded a pond. Common tealAnas creccaand green sandpiperTringa ochropuswere the species showing the most positive numerical response, but the other five species also increased upon flooding. This article evaluates how the results of the study have been used in management, both in theory and practice. The whole-community facilitation concept has been taken up in numerous articles considering the restorative effects of beavers. It has also been used as ecological background when planning and executing man-made wetland projects in Finland within both the public and the private sectors. Our study and its publication inAquatic Conservation: Marine and Freshwater Ecosystemshave set a foundation for further evidence-based management of waterbird communities. As the results show, having beavers as wetland managers is a feasible tool for creating and restoring wetlands for waterbirds and other biota. Moreover, wetland restoration projects are becoming more popular endeavours, owing to an understanding of the diverse benefits of wetlands. Flooding by beavers is used as a model for managers when creating man-made wetlands; for example, in urban areas where it is difficult to maintain beavers. 1.2.3.4.Peer reviewe

Role of forest ditching and agriculture on water quality: connecting the long-term physico-chemical subsurface state of lakes with landscape and habitat structure information.

Increasing anthropogenic pressures have affected the status of surface freshwater ecosystems. Eutrophication, water browning, acidification, and several other processes may be channelled through the food web. In this study, we evaluate the role of hydrology impacting anthropogenic pressures, flows from urban, farmland and ditched forest areas, and how they explain the physico-chemical quality of lakes and ponds in the boreal biome of Finland. We study the long-term effect around 445 waterfowl survey sites that had physico-chemical measurements (total phosphorus, total nitrogen, pH, water clarity and colour) produced by Finnish environmental authorities done in years 1986-2020. Furthermore, we investigate whether a long-term national-level citizen science study focusing on rather robust visible habitat structures measured by the volunteers can reveal physicochemical water quality using data from >270 lakes where the waterfowl habitat survey and physico-chemical measurements could be spatio-temporally matched. Farmland occurrence around the lakes was positively associated with pH, colour and nutrient concentrations but negatively associated with water clarity. Furthermore, ditch length was positively associated with nitrogen concentration and water colour, while being negatively associated with pH and water clarity. Overall, the studied lakes showed a negative trend in nutrients and clarity but a positive trend in pH and colour. As expected, nutrient concentration increased and clarity decreased along the gradient from oligotrophic to eutrophic lake habitat classifications, which suggests that the citizen science classification seem to reflect the subsurface physico-chemical status of the lakes. We conclude that farming and forest ditching practices in particular seem to associate with the state of the study lakes and that the ecological impacts of intensified turbidity and brownification in wetland ecosystems should be studied further in the future. Sustainable improvement of water quality rests upon scientific understanding of biogeochemical processes in lake ecosystems and the primary sources of the nutrient and sediment loading. (c) 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).Peer reviewe

Elinympäristön laadun ja populaatiotiheyden vaikutus sorsien lisääntymiseen ja elinympäristön käyttöön boreaalisilla kosteikoilla

The boreal biome harbours a large share of the world s wetlands, and is the main breeding area for several duck species. Breeding habitats strongly influence duck reproduction. In this study, the habitat use of ducks and their breeding success was estimated in a boreal landscape in southern Finland. A review of duck habitat use in boreal wetlands was additionally made. Boreal forest lakes are normally considered stable environments, but from a duck s point of view both resource abundance and habitat quality in the lakes may differ from one year to another. In this study the vegetation of boreal freshwater lakes was found to slowly change during the 20-year study period. Beavers (Castor canadensis) caused pronounced alterations in the lakes by flooding them. Flooding rendered lake vegetation structure more luxuriant and increased the lake use by ducks. In general, duck brood lake use was positively associated with both the coverage of wide belts of tall emergent plants and the abundance of emerging insects and aquatic invertebrates. The relative importance of these factors varied between species. The brood production of common goldeneyes (Bucephala clangula) was regulated by density dependence per se, but fluctuated with food availability per capita. No spatial density-dependent effects were found for the common teal (Anas crecca), but the breeding success was instead explained well by habitat quality variation. Both food and flood abundance had a positive effect, but different variables seemed to operate during different phases of the breeding season. Many aspects of boreal breeding ducks are still poorly studied. Especially lacking are studies concerning duckling survival and the effects of anthropogenic actions on duck habitat use. This research underlines the importance of high quality habitats for breeding duck populations in the boreal landscape. The varying habitat requirements of duck species should be considered when implementing wetland management.Boreaalisen biomin vesistöt ovat monien sorsien tärkeimpiä lisääntymisympäristöjä. Tässä tutkimuksessa selvitettiin sorsien elinympäristön käyttöä ja lisääntymismenestystä boreaalisilla kosteikoilla Evolla Hämeessä. Lisäksi boreaalisten alueiden sorsia käsittelevistä julkaisuista koottiin kirjallisuuskatsaus. Boreaalisia järviä pidetään yleensä vakaina ympäristöinä, mutta sorsien kannalta sekä ravinnon saatavuus että ympäristön laatu voivat vaihdella vuodesta toiseen. Tässä tutkimuksessa havaittiin järvikasvillisuuden muuttuneen hitaasti 20 tutkimusvuoden aikana. Amerikanmajavan (Castor canadensis) aiheuttamat tulvat muuttivat kasvillisuutta nopeasti ja voimakkaasti. Tulvaaminen lisäsi järvien kasvillisuuden rehevyyttä ja houkutteli varsinkin sorsapoikueita. Sorsapoikueiden elinympäristönkäytössä korostuivat rantakasvillisuuden ja kuoriutuvien hyönteisten sekä veden selkärangattomien määrä. Näiden tekijöiden merkitys kuitenkin vaihteli sorsilla lajikohtaisesti. Eri sorsalajien elinympäristövaatimukset tulisi huomioida kosteikkojen hoidossa. Erilaisten ravintoresurssien käyttö sekä territoriaalisuus heijastuivat myös lajien ympäristön käytön vakauteen. Telkän (Bucephala clangula) ympäristönkäytön havaittiin olevan paljon vakaampaa kuin tavin (Anas crecca). Territoriaalisen telkän poikuetuottoa sääteli suora tiheysriippuvuus, mutta myös vuotuinen ravintoresurssien vaihtelu heijastui alueelliseen poikuemäärään. Tavilla suoraa tiheysriippuvuutta ei havaittu, vaan poikuetuotto vaihteli elinympäristön laadun mukaan. Sekä ravinto että tulvat vaikuttivat positiivisesti tavipoikueiden määrään, mutta tekijät toimivat eri tavoin eri lisääntymisvaiheissa. Boreaalisilla alueilla sorsien elinympäristön valintaa ja lisääntymismenestykseen vaikuttavia tekijöitä tunnetaan vielä huonosti. Varsinkaan poikasten selviytymiseen vaikuttavia tekijöitä ja puolisukeltajasorsien pesäpaikan valintaa ei ole tutkittu. Ihmistoimien, kuten maankäytön muutosten ja järvien virkistyskäytön, vaikutusta sorsien lisääntymismenestykseen ei ole tutkittu lähes lainkaan. Tämä tutkimus korostaa hyvälaatuisten elinympäristöjen, kuten tulvikoiden, merkitystä boreaalisilla alueilla lisääntyville sorsille. Tulvikoita on boreaalisessa maisemassa suhteellisen vähän ja lisäksi ilmastonmuutoksen otaksutaan vähentävän niiden määrää entisestään sekä heikentävän niiden laatua. Majavan luomien tulvikoiden määrä on kasvanut lajin palatessa entisille elinalueilleen. Majava-tulvikoita voidaan edelleen lisätä suosimalla majavaa kosteikoiden ennallistajana

Landscape and habitat affect frequency of artificial duck nest predation by native species, but not by an alien predator

Annual Finnish breeding duck surveys over the last 30 years show declining abundance among several species and greater declines on eutrophic waters than oligotrophic lakes. It has been suggested that habitat-related differences in the rate of increase in predation pressure is a potential explanation for contrasting duck population trajectories between habitats. We assessed potential duck nest predation risk and predator presence in various duck breeding habitats in Finland and Denmark by monitoring 333 artificial duck nests with wildlife cameras during 2017-2019. Predation rates differed between landscapes and habitats: nest predation rate and predator diversity were lowest in forested and highest in agricultural landscapes. Forest nests further from water bodies survived better than nests around shorelines of permanent lakes. Of the 16 different predator species detected, the most common were Eurasian magpie (Picapica), hooded crow (Corvus corone) and raccoon dog (Nyctereutes procyonoides). While predation by specific native predator species was typically associated with particular habitats and landscapes, the alien raccoon dog appeared to be a true habitat generalist, ubiquitous and common across all habitats and landscapes. Based on these results, the higher duck nest predation pressure along shorelines, especially in agricultural landscape lakes, due to increased diversity and abundance within the predator community, may contribute to the declining population trends of ducks. (C) 2020 Gesellschaft fir okologie. Published by Elsevier GmbH. All rights reserved.Peer reviewe

Vuotohäiriöt fertiili-iän ääripäissä

Vertaisarvioitu. English summary. Teema : gynekologiset vuotohäiriöt.Toiminnallisten vuotohäiriöiden tavallisin syy on anovulaatio. Sitä esiintyy yleisimmin hedelmällisen iän ääripäissä eli parin vuoden ajan kuukautisten alkamisen jälkeen ja menopaussin siirtymävaiheessa eli perimenopaussissa. Syynä tähän on hypotalamus-aivolisäke-munasarja-akselin toimintahäiriö. Nuorilla taustalla on säätelyn kypsymättömyys ja perimenopaussissa munasarjatoiminnan hiipuminen. Anovulaatiossa progesteronin stabiloiva vaikutus kohdun limakalvon rakenteeseen jää puuttumaan. Vuotohäiriön diagnosointi ja hoito voidaan aloittaa perusterveydenhuollossa. Diagnostiikan kulmakiviä ovat tarkka oire- ja vuotoanamneesi sekä yleisvoinnin tarkistus. Nuorilla ensisijaisena hoitona ovat yhdistelmäehkäisytabletit ja perimenopausaalisilla progestiinivalmisteet. Jos tavanomaisella hormonihoidolla ei saada hoitovastetta, potilas lähetetään erikoissairaanhoitoon. Yleistilaltaan heikko ja aneeminen potilas on syytä lähettää naistentautien päivystykseen.Peer reviewe

Duck-fish competition in boreal lakes - a review

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The effect of beaver facilitation on Common Teal : pairs and broods respond differently at the patch and landscape scales

Avian species respond to ecological variability at a range of spatial scales and according to life history stage. Beaver dams create wetland systems for waterbirds that are utilized throughout different stages of the breeding season. We studied how beaver?induced variability affected mobile pairs and more sedentary broods along with the production of Common Teal Anas crecca at the patch and landscape scale on their breeding grounds. Beavers Castor spp. are ecosystem engineers that enhance waterfowl habitats by impeding water flow and creating temporary flooding. Two landscapes in southern Finland with (Evo) and without (Nuuksio) American Beavers Castor canadensis were used in this study. To investigate the patch?scale effect, pair and brood densities along with brood production were first compared at beaver?occupied lakes and non?beaver lakes in the beaver landscape. Annual pair and brood densities/km shoreline and brood production were compared between beaver and non?beaver landscapes. Facilitative effects of beaver activity were manifest on brood density at both patch and landscape scales: these were over 90 and 60 percent higher in beaver patches and landscapes, respectively. An effect of beaver presence on pair density was only seen at the landscape level. Pair density did not strongly affect brood production, as shown earlier for relatively mildly density?dependent Teal populations. Because the extent of beaver flooding was a crucial factor affecting annual Teal production in the study area, we infer beaver activity has consequences for the local Teal population. Ecosystem engineering by the beaver could therefore be considered as a restoration tool in areas where waterfowl are in need of high?quality habitats. This article is protected by copyright. All rights reserved.Peer reviewe

Volatile emission from strawberry plants is induced by mite and leaf beetle feeding and methyl jasmonate

We have studied the emission of volatile organic compounds (VOCs) from young strawberry plants, cultivars Polka and Honeoye, after feeding by several strawberry herbivores under laboratory conditions. VOC profile of strawberry plants is highly dominated by green leaf volatiles (GLVs), which are released also due to mechanical damage. Our results reveal that strawberry has potential for inducible VOC defence, and this encourages testing the attractiveness of these strawberry VOCs to predatory mites