Long-term decline in northern pike (Esox lucius L.) populations in the Baltic Sea revealed by recreational angling data

In the Baltic Sea, the large predatory fish northern pike (Esox lucius L.) is important for both recreational fisheries and ecosystem functioning. As existing fishery-independent surveys do not adequately monitor pike populations, a general lack of knowledge on population status and trends poses challenges for management. Here we use recreational angling data as an alternative method to describe pike population development along the Swedish Baltic Sea coast from 1938 onwards and assess the change over time in potential mortality factors by estimating harvest by fisheries and consumption by large predators. Data from a Swedish national register on trophy-sized pike (>12 kg) showed that numbers and maximum sizes peaked in 1990-1995, after which declines in both metrics are evident. In logbooks from a sport fishing club in the Stockholm archipelago, a simultaneous decrease in maximum sizes of pike was observed, together with a decrease in the total number of pike caught per fishing day. Jointly, these data indicate a decline in the abundance of large pike since around 1990. While commercial pike fisheries in the Baltic Sea have decreased continuously since the 1950s, recreational fishing increased after 1985, when Swedish coastal waters were made open access to anglers. The declines in large pike starting in the 1990s could, thus, have been driven by an increase in mortality from recreational fisheries, which at the time primarily practiced catch and kill. Since the 2000s, bag and slot length limits, spawning closures, and a general increase in catch-and-release fishing has reduced the landings of pike in recreational fisheries. Despite these fisheries regulations and higher release rates the decline in catches of large pike has continued, indicating an effect of other mortality factors. The strong growth of grey seal (Halichoerus grypus) and great cormorant (Phalacrocorax carbo sinensis) populations suggest that predation pressure on pike has increased over time. In the Stockholm archipelago these two predators were estimated to remove 5-18 times (range based on different diet composition estimates) more pike biomass than total fisheries landings in 2014-2017. To improve the situation for northern pike in the Baltic Sea managers need to consider both fisheries restrictions and measures to decrease predation pressure and increase recruitment. Catch data from recreational fisheries may be used to evaluate such management efforts by providing information on the population development of this keystone species

Fritidsfiskets omfattning i Vättern 2017

Fritidsfiske är en populär aktivitet med positiva ekonomiska, sociala och hälsofrämjande effekter för både den enskilde individen och för samhället. För flera av Sveriges fiskbestånd är idag fångsterna större i fritidsfisket än i yrkesfisket. På samma sätt som yrkesfisket är därför fritidsfisket en nationellt viktig resurs, men utgör samtidigt en verksamhet som belastar ekosystemen. Det åligger Sverige att bedöma fritidsfiskets ekologiska effekter och dess sociala och ekonomiska betydelse för samhälle och människor. Idag saknas dock god kunskap och robusta underlag om fritidsfiskets omfattning, värde och påverkan. Det finns därför ett behov av att samla data från fritidsfisket både för att möjliggöra en kunskapsbaserad rådgivning till fiskförvaltningen men också för att belysa fritidsfiskets omfattning och betydelse. I denna rapport undersöktes olika metoder för datainsamling inom fritidsfisket efter röding, lax och öring i Vättern under juli och november 2017, med fokus på resultat till nytta för fiskförvaltningen och bedömning av beståndens status. Två huvudsakliga undersökningar genomfördes: inventeringar av ansträngningen (antal fiskande) och en enkätundersökning för att beskriva fisket och fångsterna. Antal fiskande och deras fiskemetoder inventerades från flygplan, båt och via fritidsbåthamnar. Via enkäter samlades information om de svarandes fiskeerfarenheter och om fångsterna. Genom att kombinera de två undersökningarna estimerades sedan totalfångster av röding, öring och lax. Beräknat antal fiskande från de tre inventeringsmetoderna korrelerade väl och hade en liknande precision. Flyg- och båtinventeringen gav en bättre rumslig täckning och en säkrare bedömning att fiske faktiskt bedrivits, medan hamninventeringar av naturliga skäl är begränsade till vissa platser. Med hjälp av lokala hamnvärdar kunde dock fler dagar och flera tillfällen per dag undersökas än vad flyg- och båtinventeringar normalt medger. Från flyget, som täckte hela Vättern, estimerades antalet trollingfiskande båtar (± 1 standardfel) i juli respektive november till 1 260 (±450) och 370 (±140). För juli beräknades antalet båtar som bedrev vertikalfiske till 420 (±170) och i november fiskade 130 (±60) personer från land eller landnära med flytring. I kombination med enkätundersökningen gav detta att det i juli i trollingfisket respektive vertikalfisket totalt fångades (behållen och återutsatt fisk) 5 840 (±2 220) och 1 430 (±630) rödingar. Motsvarande fångster av lax var 940 (±520) och 15 (±15). I trollingfisket i november beräknades fångsterna av röding till 910 (±390) samt lax till 390 (±160). Fångsterna av öring var i paritet med lax i både juli och november. För alla tre arter i både trolling- och vertikalfisket återutsattes en betydande andel av de fångade fiskarna (ca 40–70 %). Kunskap om fångster av röding, öring och lax utgör ett viktigt underlag för fiskförvaltningen i Vättern. Samtidigt visar studien på tre goda exempel hur fritidsfiskets omfattning och fångster kan samlas in, där val av metod i huvudsak styrs av ett givet fritidsfiskes rumsliga och temporala utbrednin

Procedural theory - accomplishing design goals

Landscaping is the act of taking a piece of land and analysing, evaluating, and beautifying it, while focusing on maintaining and increasing sustainability, functionality, and usability for people in a resource-effective way. The course Urban Landscape Design (LK0400) is a bachelor’s level course focusing on design of urban green spaces, offered at the Swedish University of Agricultural Sciences, and run by the Department of Landscape Architecture, Planning and Management (LTV faculty). The course is run as a stand-alone course for national and international students and as a programme course in the Landscape Engineer Programme at Uppsala and Alnarp, and in the Garden Design, Landscape Engineer Programme at Alnarp

Procedural theory - mental activity progressions, sketching and drawing procedure during the design process

Landscaping is the act of taking a piece of land and analysing, evaluating, and beautifying it, while focusing on maintaining and increasing sustainability, functionality, and usability for people in a cost-effective way. The course Urban Landscape Design (LK0400) is a bachelor’s level course focusing on design of urban green spaces, offered at the Swedish University of Agricultural Sciences, and run by the Department of Landscape Architecture, Planning and Management (LTV faculty). The course is run as a stand-alone course for national and international students and as a programme course in the Landscape Engineer Programme at Uppsala and Alnarp, and in the Garden Design, Landscape Engineer Programme at Alnarp

Public engagement with marine climate change issues: (Re)framings, understandings and responses

Climate change impacts on marine environments have been somewhat neglected in climate change research, particularly with regard to their social dimensions and implications. This paper contributes to addressing this gap through presenting a UK focused mixed-method study of how publics frame, understand and respond to marine climate change-related issues. It draws on data from a large national survey of UK publics (N = 1,001), undertaken in January 2011 as part of a wider European survey, in conjunction with in-depth qualitative insights from a citizens’ panel with participants from the East Anglia region, UK. This reveals that discrete marine climate change impacts, as often framed in technical or institutional terms, were not the most immediate or significant issues for most respondents. Study participants tended to view these climate impacts ‘in context’, in situated ways, and as entangled with other issues relating to marine environments and their everyday lives. Whilst making connections with scientific knowledge on the subject, public understandings of marine climate impacts were mainly shaped by personal experience, the visibility and proximity of impacts, sense of personal risk and moral or equity-based arguments. In terms of responses, study participants prioritised climate change mitigation measures over adaptation, even in high-risk areas. We consider the implications of these insights for research and practices of public engagement on marine climate impacts specifically, and climate change more generally

Outstanding challenges in the transferability of ecological models

Predictive models are central to many scientific disciplines and vital for informing management in a rapidly changing world. However, limited understanding of the accuracy and precision of models transferred to novel conditions (their ‘transferability’) undermines confidence in their predictions. Here, 50 experts identified priority knowledge gaps which, if filled, will most improve model transfers. These are summarized into six technical and six fundamental challenges, which underlie the combined need to intensify research on the determinants of ecological predictability, including species traits and data quality, and develop best practices for transferring models. Of high importance is the identification of a widely applicable set of transferability metrics, with appropriate tools to quantify the sources and impacts of prediction uncertainty under novel conditions