Siia Coregonus lavaretus L. s. l. kasv ja viljakus Soome lahes

https://www.ester.ee/record=b5451999*es

Merisiig Eesti rannikumeres: vormid, kasv, toitumine, viljakus

https://www.ester.ee/record=b3596029*es

Essential coastal habitats for fish in the Baltic Sea

Many coastal and offshore fish species are highly dependent on specific habitat types for population maintenance. In the Baltic Sea, shallow productive habitats in the coastal zone such as wetlands, vegetated flads/lagoons and sheltered bays as well as more exposed rocky and sandy areas are utilized by fish across many life history stages including spawning, juvenile development, feeding and migration. Although there is general consensus about the critical importance of these essential fish habitats (EFH) for fish production along the coast, direct quantitative evidence for their specific roles in population growth and maintenance is still scarce. Nevertheless, for some coastal species, indirect evidence exists, and in many cases, sufficient data are also available to carry out further quantitative analyses. As coastal EFH in the Baltic Sea are often found in areas that are highly utilized and valued by humans, they are subjected to many different pressures. While cumulative pressures, such as eutrophication, coastal construction and development, climate change, invasive species and fisheries, impact fish in coastal areas, the conservation coverage for EFH in these areas remains poor. This is mainly due to the fact that historically, fisheries management and nature conservation are not integrated neither in research nor in management in Baltic Sea countries. Setting joint objectives for fisheries management and nature conservation would hence be pivotal for improved protection of EFH in the Baltic Sea. To properly inform management, improvements in the development of monitoring strategies and mapping methodology for EFH are also needed. Stronger international cooperation between Baltic Sea states will facilitate improved management outcomes across ecologically arbitrary boundaries. This is especially important for successful implementation of international agreements and legislative directives such as the Baltic Sea Action Plan, the Marine Strategy Framework Directive, the Habitats Directive, and the Maritime Spatial Planning Directive, but also for improving the communication of information related to coastal EFH among researchers, stakeholders, managers and decision makers. In this paper, efforts are made to characterize coastal EFH in the Baltic Sea, their importance and the threats/pressures they face, as well as their current conservation status, while highlighting knowledge gaps and outlining perspectives for future work in an ecosystem-based management framework. (C) 2018 Elsevier Ltd. All rights reserved.Peer reviewe

Ohustatud sh kaitsealuste ja vääriskalaliikide seisundi parandamiseks vajalikud meetmed ja eelistatud tegevused

Eesti kalavaru, sh vähivaru kasutamine peab olema kooskõlas nii rahvusvaheliselt kui Eestis heakskiidetud säästva arengu põhimõtetega. Loodusvarade säästva kasutamise eesmärk on inimest rahuldava elukeskkonna ja majanduse arenguks vajalike ressursside tagamine, sealjuures oluliselt kahjustamata elukeskkonda ning säilitades looduslikku mitmekesisust. Kalavaru kaitset ja suurust saab mõjutada püügi reguleerimisega, elukeskkonna kaitse, parandamise või taastamisega ning kalakasvatusliku taastootmise abil. Viimane neist on kulukas tegevus, mis eeldab pikaajalist planeerimist ja otstarbekuse analüüsi. Selleks on vajalik kalavarude taastootmise tegevuskava. Tegevuskava koostamisel on lähtutud Eesti ja rahvusvahelistest valdkondlikest dokumentidest arvestades seejuures hetkeolukorda, kalavarude seisundit ja taastamise vajadust ning olemasolevaid võimalusi. Tegevuskava eesmärk on kalakasvatusliku taastootmise abil parandada ohustatud sh kaitsealuste kalaliikide seisundit ja suurendada nende arvukust, luues avaramad võimalused ka vääriskalaliikide püügiks Eestis. Tegevuskava elluviimist koordineerib ja selle eest vastutab Keskkonnaministeeriumi kalavarude osakond. Vastutav koordinaator koos tegevuskava täitjatega koostab iga nelja aasta tagant tegevuskava täitmise kokkuvõtte. Vastavalt saavutatud tulemustele ja ilmnenud puudustele muudetakse kava, et korrigeerida kalakasvatusliku taastootmise suundasid kalavarude olukorra parandamiseks ja bioloogilise mitmekesisuse hoidmiseks.Programmi koostamist finantseeris Keskonnainvesteeringute Kesku

Whitefish

201

Quantification of the Early Small-Scale Fishery in the North-Eastern Baltic Sea in the Late 17th Century

<div><p>Historical perspectives on fisheries and related human behaviour provide valuable information on fishery resources and their exploitation, helping to more appropriately set management targets and determine relevant reference levels. In this study we analyse historical fisheries and fish trade at the north-eastern Baltic Sea coast in the late 17th century. Local consumption and export together amounted to the annual removal of about 200 tonnes of fish from the nearby sea and freshwater bodies. The fishery was very diverse and exploited altogether one cyclostome and 17 fish species with over 90% of the catch being consumed locally. The exported fish consisted almost entirely of high-valued species with Stockholm (Sweden) being the most important export destination. Due to rich political history and natural features of the region, we suggest that the documented evidence of this small-scale fishery should be considered as the first quantitative summary of exploitation of aquatic living resources in the region and can provide a background for future analyses.</p></div

Export amounts of five most important species from Narva during the years 1662–1699.

<p>Expressed as median ±50% quartiles.</p

Seal-induced losses and successful mitigation using Acoustic Harassment Devices in Estonian Baltic trap-net fisheries

During the last decades the number of grey seals Halichoerus grypus has increased more than tenfold in the Baltic Sea. having reached 38 000 in 2019, which has created increasing problems to the coastal fisheries. In the current study, 151 Estonian coastal fishermen were interviewed to sum all direct and indirect monetary losses. The total cost of the damage caused by seals to the Estonian fisheries was around 0.9 million euros in 2009. With the aim of mitigating seal impact, Acoustic Harassment Devices (AHDs, Lofitech) were tested. This study presents quantitative data on seal damage in Estonian trap-net fisheries and analyses the results of the attempts made to mitigate the damage by means of AHDs. It can be concluded that AHDs provided sufficient protection against the seal attacks

Map showing location of Narva town and surrounding areas.

<p>Names of the countries and/or provinces during the end of the 17th century are given in italics.</p