| 1. |
- Alonso Aller, Elisa, 1984-
(författare)
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Effects of Marine Protected Areas on Tropical Seagrass Ecosystems
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Seagrass beds are highly productive coastal ecosystems that sustain a rich and diverse associated fauna and flora. Increasing anthropogenic pressures threaten seagrass ecosystems and have already led to major seagrass losses across the world. Marine Protected Areas (MPAs) have become one of the key strategies to manage coastal ecosystems and associated resources worldwide and have been often shown to successfully protect marine ecosystems. However, relatively few studies have assessed the effects of MPAs on seagrass ecosystems, and there are indications that MPAs may not be able to fully protect seagrasses, especially from disturbances originating outside their boundaries. Within this context, this thesis aimed to investigate the direct and indirect effects (those mediated by biotic interactions) of MPAs on tropical seagrasses, associated fish communities, and ecosystem processes.The thesis consists of three parts. First, we used 10-years of seagrass monitoring data within a MPA to evaluate the temporal variability in seagrass cover and species composition in relation to changes in environmental conditions (Paper I). Second, we investigated the potential of MPAs to enhance the temporal stability of seagrass ecosystems using a 10-month field study. We surveyed seagrass-associated fish communities (Paper II) and estimated seagrass growth and herbivory rates (Paper III) during three different seasons within MPAs and unprotected sites. Finally, to evaluate the effects of MPAs and land-use on seagrass ecosystems we surveyed seagrass species and trait composition within government-managed MPAs, community-managed MPAs, and unprotected sites (Paper IV).The seagrass bed monitored in Paper I showed a high temporal and spatial variability, with a temporal decline in cover and change in species composition, followed by a period of recovery. This pattern could not be associated with any of the climate and tidal variables considered, suggesting that potential drivers of decline may have originated outside MPA boundaries. The results from the seasonal field study showed that MPAs increased the temporal stability of seagrass-associated fish communities, particularly juvenile fish (Paper II), and strengthened a positive link between herbivorous fish, herbivory rates, and seagrass growth (Paper III), suggesting the presence of a positive feedback that promotes stability. Finally, MPAs affected seagrass species and trait composition (by selecting for more stress-sensitive species) but did not seem to be able to protect seagrasses from land-use effects, with seagrasses showing similar changes in species and trait composition within and outside MPAs (Paper IV). Considering these results, this thesis builds to a body of literature indicating that MPAs alone may not be sufficient to protect seagrass ecosystems and that improved management strategies may be necessary to preserve these important coastal habitats.
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| 2. |
- Bergström, Lena, et al.
(författare)
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Effekter av havsbaserad vindkraft på marint liv : En syntesrapport om kunskapsläget 2021
- 2022
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Att öka tillgången på förnybar energi är nödvändigt för att motverka klimatförändringarna. Här förväntas havsbaserad vindkraft ha en viktig roll. Samtidigt medför planer på att bygga ut havsbaserad vindkraft viktiga frågeställningar kring hur marint liv och biologisk mångfald kan påverkas. I den här rapporten sammanställs det nuvarande kunskapsläget om hur havsbaserad vindkraft skulle kunna påverka marint liv, med fokus på svenska havsområden. Temamässigt omfattar rapporten bottennära miljöer, fisk, marina däggdjur och sjöfågel. Den strävar även efter att belysa kunskapsläget kring kumulativa effekter, samt frågor om under vilka förutsättningar havsbaserad vindkraft skulle kunna gynna marint liv.Bedömningarna beaktar även hur det tekniska utförandet har utvecklats, till exempel när det gäller vindparkernas utformning och dimensionering. Planeringen idag omfattar större vindparker och kraftverk, och bottenfasta vindkraftverk kan lokaliseras på allt större djup. De har hittills främst etablerats inom djupintervallet 5–40 meter, men kan numera anläggas på omkring 40–60 meters djup. Därtill förväntas flytande fundament, som klarar ännu större djup, bli vanligare. En annan viktig aspekt är hur tillämpningen av skadelindrande åtgärder har utvecklats.Havsbaserad vindkraft förväntas påverka marint liv på olika sätt under anläggnings- och driftsfasen, varför det är relevant att tydligt särskilja dessa i riskbedömningar. Rapporten berör även effekter under avvecklingsfasen.Under anläggningsfasen, som pågår någon dag per kraftverk, kan högintensivt ljud uppstå till exempel i samband med pålning av vindkraftverkens fundament. Åtgärder för att minska skadeverkningar av högintensivt ljud är viktiga, och kan förutsättas vara standard idag. Ofta finns det även behov att förbereda havsbotten, vilket leder till spridning av sedimentpartiklar. Omfattningen av både ljud- och sedimentspridning beror på lokala förhållanden. Därför behöver de lokala förhållandena beaktas för att ta fram en mer detaljerad kännedom om risker för marint liv. I synnerhet tumlare kan påverkas negativt av höga ljudnivåer vid anläggningsfasen, med risk för hörselpåverkan och kraftiga beteendestörningar om inte skadelindrande åtgärder används. Särskilda hänsyn i lokalisering och utförande kan även behövas för sälar, samt för fisk när det gäller områden och årstider som är viktiga för deras reproduktion. Under driftsfasen, som pågår upp emot cirka 40 år, bildar vindkraftverkens fundament och eventuella erosionsskydd fasta strukturer. Detta kan ge upphov till reveffekter då ytorna skapar plats för fastsittande arter. Med tiden kan även fiskar och marina däggdjur lockas dit, om förhållandena medger det. En viktig skillnad jämfört med andra typer av rev är att fundamenten går hela vägen upp till ytan, vilket ökar tillgången på hårda substrat i hela vattenpelaren. En möjlig risk är att de nya substraten skulle kunna gynna oönskade främmande arter, även om det saknas belägg för vindparkernas roll som en sådan spridningsväg.När elen produceras genereras undervattensljud, och överföringen av el i sjökablar kan leda till ett visst mått av elektromagnetiska fält i kablarnas närhet. Effekter av dessa påverkansfaktorer har varit svåra, om inte omöjliga, att notera i fältundersökningar. En generell slutsats skulle kunna vara att, om det förekommer negativa effekter av undervattensljud och elektromagnetiska fält, så är de oftast i styrka underordnade den attraktion som kommer av reveffekten. Aktuella studier tyder sammanfattningsvis på att havsbaserad vindkraft under driftsfasen inte är ett hot mot fiskar, säl eller tumlare. Särskild hänsyn när det gäller lokalisering kan dock behövas för skyddsvärda bottenmiljöer samt sjöfågel. Vissa sjöfågelarter kommer sannolikt att undvika området där vindparken etableras. Även åtgärder för att minska dödlighet kopplad till att fåglar kolliderar med kraftverken kan vara viktiga i vissa områden. Eftersom slutsatserna baseras på studier i andra miljöer än de som kan bli aktuella i Sverige framöver är en uppföljning av miljöeffekter viktig i de parker som etableras, för att ha möjlighet att säkerställa eller vid behov revidera kunskapsläget.Utveckling av kunskapsläget När det gäller vindkraftens effekter på bottennära livsmiljöer har kunskapsläget förbättrats angående mer långsiktig påverkan, liksom hur alg- och djursamhället i vindparken förändras över tid. Med åren blir det mer och mer likt det naturliga samhället på hårda bottnar i den aktuella regionen, även om arter med långlivade larvstadier främjas relativt sett mer. I viss mån saknas kunskap om vilken påverkan som kan förväntas om man bygger på större djup och om vindkraftverken står glesare, som planeras idag. Inga studier tyder dock på att etablering av vindkraftverk är ett hot mot vegetation eller bottenlevande djur i den här typen av miljöer, så länge särskilt skyddsvärda livsmiljöer undviks.Angående fisk och fisksamhällen har förståelsen för reveffekter ökat. Forskningen har övergått till att belysa reveffekter mer ingående, från att tidigare främst bekräfta om det blir en reveffekt eller inte. Sådana studier saknas dock idag för flera svenska havsområden eftersom det inte finns vindparker där.För marina däggdjur har kunskapsläget förbättrats framför allt när det gäller förståelsen av hur sälar och tumlare uppfattar och använder sig av ljud, samt hur ljud av olika frekvens och intensitet påverkar djuren.Kunskapen som hur havsbaserad vindkraft kan påverka sjöfågel har förbättrats framför allt för kustnära områden, men bedömningar begränsas fortfarande av otillräcklig kunskap om olika sjöfågelarters utbredning och dynamik i förekomst mellan år. Det här gäller speciellt områden längre ut till havs och med större djup än 30 meter. Den internationella forskningen har varit fokuserad på att bedöma kollisionsrisk, och ny teknik har gett ökad kunskap om fåglars flyghöjder och beteenden i förhållande till vindkraftverk.Kumulativa effekterFör att göra en sammanvägd bedömning av vindkraftens miljöeffekter är det relevant att sätta de enskilda bedömningarna i ett vidare sammanhang, där även till exempel aktuell miljöstatus och effekter av annan verksamhet ingår, så som omfattningen av fiske och sjöfart. I ett sådant perspektiv skulle införandet av en vindpark kunna leda till att den totala omfattningen av påverkan antingen ökar eller minskar i ett visst område. Etableringen kan också påverka samspelet mellan arter, med efterföljande indirekta effekter i ekosystemet. Att förstå sådana sammanvägda effekter är ett fortsatt viktigt forskningsområde. Det finns även ett behov av att utveckla metoder för att skatta kumulativa effekter i samband med havsbaserad vindkraft på olika rumsliga och tidsmässiga skalor. Utgående från det befintliga kunskapsläget kan risken för att havsbaserade vindparker bidrar med negativa kumulativa effekter på havsmiljön förväntas vara låg, under förutsättning att skadelindrande åtgärder tillämpas och bästa möjliga hänsyn tas. Under anläggningsfasen innebär sådana förutsättningar att skadliga nivåer av påverkansfaktorn minimeras, och att anläggningen sker under sådana rumsliga och tidsmässiga förhållanden att risken för ansamling av känsliga populationer av fisk och marina däggdjur minimeras. Bedömningen beror på att påverkan under anläggningsfasen är tidsmässigt övergående och inte förväntas upprepas vid mer än ett tillfälle per plats. Det baseras därför också på förutsättningen att annan motsvarande verksamhet inte sker samtidigt i området. För driftsfasen innebär förutsättningarna att driften sker med sådan teknik att nivån av elektromagnetiska fält är låg och att undervattensljud inte leder till negativa effekter på fisk eller marina däggdjur, och med undantag av att det fortsatt finns oklarheter kring hur sjöfågel kan påverkas.Vid en omfattande utbyggnad kommer gradvis högre hänsyn och anpassningar för att undvika kumulativa effekter att vara motiverade. Det ställer även ökade krav på nationell och internationell samordning för att undvika risker för kumulativ påverkan i samband med anläggningsfasen, till exempel om flera vindparker anläggs parallellt. Eftersom vindkraftens långsiktiga bidrag till kumulativ påverkan är svårbedömda i dagsläget, och förväntas variera både lokalt och mellan olika havsområden, vore det mycket viktigt att följa utvecklingen över tid i sådana parker som etableras, för att öka kunskapen och skapa möjlighet att vid behov införa åtgärder för att minska risker för specifika arter.Kan vindkraften ha positiva effekter på marint liv?Forskningen innehåller även exempel på när införandet av havsbaserad vindkraft kan ha gynnat arter, eller aspekter av biologisk mångfald och ekosystemtjänster. Det finns dock en svårighet med att generalisera kring om havsbaserad vindkraft kan gynna marint liv, eftersom utfallet i hög grad beror på vindparkens lokalisering, ekologiska förutsättningar, samt vilka andra aktiviteter som förekommer i närområdet. En viktig aspekt är även att mänskliga preferenser påverkar definitionen av om viss förändring i artsammansättning är ”positiv” eller ”negativ”, eftersom det här beror på hur olika arter och ekosystemstjänster värdesätts, det vill säga vilken typ av biologisk mångfald som är önskvärd i ett visst område. Rapporten redogör för olika typer av anpassningar som har förslagits för att gynna särskilda arter i samband med havsbaserad vindkraft, även om utvecklingen av sådana naturanpassade lösningar fortfarande är i sin linda.
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| 3. |
- Bergström, Ulf, et al.
(författare)
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Inför fler fiskefria områden för att skydda bestånd och ekosystem
- 2024
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Fiskefria områden kan vara ett effektivt verktyg för att skydda både fisk- och kräftdjursbestånd och marina ekosystem. Men det är viktigt att områdena utformas på rätt sätt och är tillräckligt stora. Lektidsfredade områden kan vara enklare att driva igenom, men ger inte lika goda effekter.
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| 4. |
- Bergström, Ulf, et al.
(författare)
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Long-term effects of no-take zones in Swedish waters
- 2022
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Marine protected areas (MPAs) are increasingly established worldwide to protect and restore degraded ecosystems. However, the level of protection varies among MPAs and has been found to affect the outcome of the closure. In no-take zones (NTZs), no fishing or extraction of marine organisms is allowed. The EU Commission recently committed to protect 30% of European waters by 2030 through the updated Biodiversity Strategy. Importantly, one third of these 30% should be of strict protection. Exactly what is meant by strict protection is not entirely clear, but fishing would likely have to be fully or largely prohibited in these areas. This new target for strictly protected areas highlights the need to evaluate the ecological effects of NTZs, particularly in regions like northern Europe where such evaluations are scarce. The Swedish NTZs made up approximately two thirds of the total areal extent of NTZs in Europe a decade ago. Given that these areas have been closed for at least 10 years and can provide insights into long-term effects of NTZs on fish and ecosystems, they are of broad interest in light of the new 10% strict protection by 2030 commitment by EU member states.In total, eight NTZs in Swedish coastal and offshore waters were evaluated in the current report, with respect to primarily the responses of focal species for the conservation measure, but in some of the areas also ecosystem responses. Five of the NTZs were established in 2009-2011, as part of a government commission, while the other three had been established earlier. The results of the evaluations are presented in a synthesis and also in separate, more detailed chapters for each of the eight NTZs. Overall, the results suggest that NTZs can increase abundances and biomasses of fish and decapod crustaceans, given that the closed areas are strategically placed and of an appropriate size in relation to the life cycle of the focal species. A meta-regression of the effects on focal species of the NTZs showed that CPUE was on average 2.6 times higher after three years of protection, and 3.8 times higher than in the fished reference areas after six years of protection. The proportion of old and large individuals increased in most NTZs, and thereby also the reproductive potential of populations. The increase in abundance of large predatory fish also likely contributed to restoring ecosystem functions, such as top-down control. These effects appeared after a 5-year period and in many cases remained and continued to increase in the longer term (>10 years). In the two areas where cod was the focal species of the NTZs, positive responses were weak, likely as an effect of long-term past, and in the Kattegat still present, recruitment overfishing. In the Baltic Sea, predation by grey seal and cormorant was in some cases so high that it likely counteracted the positive effects of removing fisheries and led to stock declines in the NTZs. In most cases, the introduction of the NTZs has likely decreased the total fishing effort rather than displacing it to adjacent areas. In the Kattegat NTZ, however, the purpose was explicitly to displace an unselective coastal mixed bottom-trawl fishery targeting Norway lobster and flatfish to areas where the bycatches of mature cod were smaller. In two areas that were reopened to fishing after 5 years, the positive effects of the NTZs on fish stocks eroded quickly to pre-closure levels despite that the areas remained closed during the spawning period, highlighting that permanent closures may be necessary to maintain positive effects.We conclude from the Swedish case studies that NTZs may well function as a complement to other fisheries management measures, such as catch, effort and gear regulations. The experiences from the current evaluation show that NTZs can be an important tool for fisheries management especially for local coastal fish populations and areas with mixed fisheries, as well as in cases where there is a need to counteract adverse ecosystem effects of fishing. NTZs are also needed as reference for marine environmental management, and for understanding the effects of fishing on fish populations and other ecosystem components in relation to other pressures. MPAs where the protection of both fish and their habitats is combined may be an important instrument for ecosystembased management, where the recovery of large predatory fish may lead to a restoration of important ecosystem functions and contribute to improving decayed habitats.With the new Biodiversity Strategy, EUs level of ambition for marine conservation increases significantly, with the goal of 30% of coastal and marine waters protected by 2030, and, importantly, one third of these areas being strictly protected. From a conservation perspective, rare, sensitive and/or charismatic species or habitats are often in focus when designating MPAs, and displacement of fisheries is then considered an unwanted side effect. However, if the establishment of strictly protected areas also aims to rebuild fish stocks, these MPAs should be placed in heavily fished areas and designed to protect depleted populations by accounting for their home ranges to generate positive outcomes. Thus, extensive displacement of fisheries is required to reach benefits for depleted populations, and need to be accounted for e.g. by specific regulations outside the strictly protected areas. These new extensive EU goals for MPA establishment pose a challenge for management, but at the same time offer an opportunity to bridge the current gap between conservation and fisheries management.
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| 5. |
- Berkström, Charlotte, et al.
(författare)
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Assessing connectivity in a tropical embayment : Fish migrations and seascape ecology
- 2013
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Ingår i: Biological Conservation. - : Elsevier BV. - 0006-3207 .- 1873-2917. ; 166, s. 43-53
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Tidskriftsartikel (refereegranskat)abstract
- Seascape connectivity and configuration of multiple habitats are important features to include in marine spatial planning, and protecting seascapes with high connectivity is recommended. The present study examines the potential connectivity of reef fish assemblages in a shallow-water conservation area in Zanzibar (Tanzania) by analysing relationships between a set of habitat variables and fish diversity and density for different functional groups (based on diet) and life stages of fish using PLS-analysis. We combined spatial pattern metrics (habitat type, patch size, distance to patch) and dispersal abilities of a number of fish species using buffer radius to answer the questions; (i) do coral reefs with high connectivity to seagrass habitats have higher abundances and higher species richness of fish that undertake routine migrations during their life-history? and (ii) do coral reefs closer to mangrove forest support higher abundances of nursery species (i.e., fish species that use mangrove and seagrass beds as juvenile habitat)? Habitat mosaics surrounding fish survey sites and within-patch measurements inside fish survey sites were quantified at multiple scales (meters to kilometers) using aerial photography and scuba. Fish data was collected using a standardized point census method. We found that both fine- and broad-scale variables were important in structuring fish communities and connectivity with surrounding habitats, where predominantly seagrass beds within a 750 m radius had a positive influence on fish abundances of invertebrate feeders/piscivores (especially for lutjanids and lethrinids). Additionally, fine-scale seagrass cover had a positive influence on nursery species. Depth also had a positive influence on total species richness and the abundance of invertebrate feeders/piscivores. This study highlights the importance of combining connectivity and habitat configuration at different scales to fully understand and manage the tropical seascape.
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| 6. |
- Berkström, Charlotte, 1978-, et al.
(författare)
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Ecological connectivity and niche differentiation between two closely related fish species in the mangrove−seagrass−coral reef continuum
- 2013
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Ingår i: Marine Ecology Progress Series. - : Inter-Research Science Center. - 0171-8630 .- 1616-1599. ; 477, s. 201-215
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Tidskriftsartikel (refereegranskat)abstract
- We aim to understand ontogenetic shifts in habitat use and feeding patterns by 2 fish species, Lutjanus fulviflamma and L. ehrenbergii, within a tropical seascape in East Africa. Stomach contents and stable isotope signatures of muscle tissues (δ13C and δ15N) were compared between and within species. Fish of all life stages and potential food items were sampled from mangrove creeks, seagrass beds, and coral reefs around Mafia Island, Tanzania. Due to similarities in morphology between species, correct species identity was confirmed using genetic barcoding (mtDNA, partial sequence of cytochrome oxidase subunit I [COI]). Stable isotope analysis in R (based on mixing models) confirmed that δ13C and δ15N values in L. fulviflamma and L. ehrenbergii reflected those of prey items caught in different habitats. Diets and mean δ13C and δ15N values of muscle tissue differed between life stages of fish, indicating ontogenetic changes in habitat and diet. L. fulviflamma and L. ehrenbergii differed in diet and δ13C and δ15N values of muscle tissue, although they overlapped in habitat use, suggesting food resource partitioning between the 2 species. Furthermore, diet overlap indexes were low between subadult species in mangrove and seagrass or coral habitats. L. fulviflamma displayed a diet shift with decreasing importance of small crustaceans in juveniles and an increasing importance of prey fishes in subadults and adults. L. ehrenbergii showed the opposite pattern. The study verifies feeding interlinkage within the mangrove-seagrass-coral reef continuum in Mafia Island by providing strong evidence of ontogenetic migration. Understanding these connections will enhance our ability to manage tropical seascapes, and highlights the need to include multiple habitats in marine protected areas.
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| 7. |
- Berkström, Charlotte, 1978-
(författare)
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Ecological connectivity in East African seascapes
- 2012
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Coral reefs, seagrass beds and mangroves constitute a complex mosaic of habitats referred to as the tropical seascape. Great gaps exist in the knowledge of how these systems are interconnected. This thesis sets out to examine ecological connectivity, i.e. the connectedness of ecological processes across multiple scales, in Zanzibar and Mafia Island, Tanzania. Paper I examined the current knowledge of interlinkages and their effect on seascape functioning, revealing that there are surprisingly few studies on the influences of cross-habitat interactions and food-web ecology. Furthermore, 50% of all fish species use more than one habitat and 18% of all coral reef fish species use mangrove or seagrass beds as juvenile habitat in Zanzibar. Paper II examined the seascape of Menai Bay, Zanzibar using a landscape ecology approach and studied the relationship between fish and landscape variables. The amount of seagrass within 750m of a coral reef site was correlated with increased invertebrate feeder/piscivore fish abundance, especially Lethrinidae and Lutjanidae, which are known to perform ontogenetic and feeding migrations. Within patch seagrass cover was correlated with nursery species abundance. Paper III focused on a seagrass-dominated seascape in Chwaka Bay, Zanzibar and showed that small-scale habitat complexity (shoot height and density) as well as large-scale variables such as distance to coral reefs affected abundance and distribution of a common seagrass parrotfish Leptoscarus vaigiensis. Paper IV studied the connectivity and functional role of two snappers (Lutjanus fulviflamma and L. ehrenbergii) using stable isotopes (δ15N and δ13C) and found that connectivity between habitats was maintained by ontogenetic and foraging migrations by these species. The thesis concludes that ecological connectivity and multi-habitat usage by fish is a general and important characteristic in the Western Indian Ocean and should be considered in management planning.
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| 8. |
- Berkström, Charlotte, et al.
(författare)
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Ecological connectivity in marine protected areas in Swedish Baltic coastal waters - A coherence assessment
- 2022
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The Department of Aquatic Resources at the Swedish University of Agricultural Sciences (SLU Aqua) was commissioned by the Swedish Agency for Marine and Water Management to assess the ecological coherence of the marine protected area (MPA) network along the Swedish Baltic Sea coast, focusing on ecological connectivity and representativity, and species performing active migrations. The study also aimed to test the influence of anthropogenic pressures on connectivity and identify areas for expansion of the existing MPA network to maximise connectivity in the region. This report is the first to assess large-scale connectivity and ecological coherence of the MPA network in the Baltic Sea with a focus on coastal habitat-forming vegetation and fish species with active dispersal. Information on dispersal/migration distances was combined with species distribution models to produce connectivity maps. To align the coherence analyses with the conservation targets specified by responsible authorities, we included the nested targets for specific species ("preciserade bevarandevärden” in Swedish) listed within the Swedish framework for MPAs. Fish species like eel, salmon and trout, as well as birds and seals, which are also listed as nested targets, were not included in our analyses, since connectivity models of these long-distance migrants would be redundant as they do not affect the more small-scale connectivity patterns that are in focus in this study.Hotspot areas for connectivity were identified, and these were generally concentrated in a few, relatively small areas. These hotspot areas are, however, highly susceptible to coastal development and human activities, as they are often situated in bays, inlets and topographically complex archipelagos. Anthropogenic pressures, in this case physical disturbance, had a relatively large predicted impact on connectivity, particularly on certain species. The majority of these species are of freshwater origin and have shorter migration distances (e.g. crucian carp, roach, common rudd, common bream/silver bream, and common bleak) than marine species like cod, flounder and herring, which perform long-distance migrations between open sea and coastal areas as part of their life cycle. Also large predatory fish like pike, pike-perch and perch, as well as habitat-forming submerged aquatic vegetation (SAV), showed a pronounced decrease in connectivity when incorporating physical disturbance into the models. This may be explained by most human pressures being concentrated along the coastline, often in shallow sheltered bays and inlets where human development coincides with sensitive vegetated habitats and important breeding, spawning, nursery and feeding grounds for fish. Connectivity is reduced when habitats become fragmented or diminished and populations become smaller and more isolated. This may in turn have consequences on genetic diversity, viability of populations and ultimately ecosystem functioning.Representativity of habitats; i.e. amount of habitat protected, was below what is generally scientifically recommended and the new target of 30% protection by 2030 in the EU Biodiversity Strategy for all but three species (of 30 in total). Representativity was very poor regarding strict MPAs, an average of 2% across species. The target according to the EU Biodiversity Strategy is 10% strict protection. Similar results were found for connectivity where the amount connected habitat within MPAs was low. MPAs in the study area were sufficiently spaced (distance apart), but dominated by MPAs of small size. Priority areas with high connectivity (identified by the spatial prioritization software prioritizr) were insufficiently protected and the connectivity of the network could be greatly improved with targeted protection in just a few important locations. Areas that are well connected locally, but are isolated from other priority areas, are especially important to protect as they are critical to connectivity of the network. Regulations within the MPA network in Swedish Baltic Sea coastal waters are generally weak, particularly in the priority areas. Applying an ecosystem-based management approach and including stronger regulations of fisheries and of activities causing local physical disturbance in parts of the MPA network is encouraged in order to reach conservation goals. The results from this study can be used to improve planning and management of the Baltic Sea MPA network, marine spatial planning in the region and improving the green infrastructure, securing important ecosystem services for future generations.
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| 9. |
- Berkström, Charlotte, et al.
(författare)
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Ecological connectivity of the marine protected area network in the Baltic Sea, Kattegat and Skagerrak: Current knowledge and management needs
- 2022
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Ingår i: AMBIO: A Journal of the Human Environment. - : Springer Science and Business Media LLC. - 0044-7447 .- 1654-7209. ; 51, s. 1485-1503
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Forskningsöversikt (refereegranskat)abstract
- Marine protected areas (MPAs) have become a key component of conservation and fisheries management to alleviate anthropogenic pressures. For MPA networks to efficiently promote persistence and recovery of populations, ecological connectivity, i.e. dispersal and movement of organisms and material across ecosystems, needs to be taken into account. To improve the ecological coherence of MPA networks, there is hence a need to evaluate the connectivity of species spreading through active migration and passive dispersal. We reviewed knowledge on ecological connectivity in the Baltic Sea, Kattegat and Skagerrak in the northeast Atlantic and present available information on species-specific dispersal and migration distances. Studies on genetic connectivity are summarised and discussed in relation to dispersal-based analyses. Threats to ecological connectivity, limiting dispersal of populations and lowering the resilience to environmental change, were examined. Additionally, a review of studies evaluating the ecological coherence of MPA networks in the Baltic Sea, Kattegat and Skagerrak was performed, and suggestions for future evaluations to meet management needs are presented.
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| 10. |
- Berkström, Charlotte, et al.
(författare)
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Ecological versatility and its importance for the distribution and abundance of coral reef wrasses
- 2012
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Ingår i: Marine Ecology Progress Series. - : Inter-Research Science Center. - 0171-8630 .- 1616-1599. ; 461, s. 151-163
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Tidskriftsartikel (refereegranskat)abstract
- Ecological versatility, the degree to which organisms fully exploit the available resources, is an important component of ecological and evolutionary theory. However, patterns and consequences of versatility in coral reef fish have received little attention. Using a comparative approach, this study tested the consequences of ecological versatility on the distribution and abundance of juvenile wrasses (family: Labridae) in Kimbe Bay, Papua New Guinea. Resource use was examined along 4 different resource axes (horizontal distribution or reef zone, vertical distribution or depth, microhabitat and diet). Stepwise multiple regressions were used to test for relationships between niche breadth and patterns of abundance and distribution. Most exhibited a degree of apparent specialisation on at least one resource, but none were specialised along all resource axes. In terms of juvenile diet, the majority of species exhibited a high reliance on harpacticoid copepods. Microhabitat specialisation was associated with low local abundance and narrow distribution among depth zones. However, diet and macrohabitat specialisation were poor predictors of local abundance, and no relationships between local abundance, and local and regional distribution were observed. We conclude that the relationship between versatility and abundance/distribution is dependent on the resource in question. A greater understanding of the degree of ecological versatility in relation to different resources is necessary to predict how reef fishes will respond to escalating human impacts on coral reefs.
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