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The discovery of individuals of softmouth trout Salmo obtusirostris in the marine environment has been recorded several times in the period from 2015 to the present day in the wider area of the Neretva River delta and southern Adriatic coast. Although this phenomenon appears to be happening more frequently along the Adriatic coast, scientific reports regarding family Salmonidae species found in the marine environment are still very rare in the eastern Adriatic, especially for the softmouth trout. The findings reported here represent the first marine records of this endemic freshwater species. An increasing frequency of these findings may indicate that a higher number of individuals are ending up in the coastal environment during heavy storm events or other unusual hydrologic occurrence. Extreme weather conditions have become more frequent in recent years, mainly as a result of climate change and have led to unexpected phenomena and impacts on nature. The long-term effects on fish and community structure of rivers flowing into the sea require further research, as these weather-induced situations can be expected to become more common. Further investigation into the physiological costs and population consequences of these unusual ecological findings is warranted.

The threat posed by invasive non-native species worldwide requires a global approach to identify which introduced species are likely to pose an elevated risk of impact to native species and ecosystems. To inform policy, stakeholders and management decisions on global threats to aquatic ecosystems, 195 assessors representing 120 risk assessment areas across all six inhabited continents screened 819 non-native species from 15 groups of aquatic organisms (freshwater, brackish, marine plants and animals) using the Aquatic Species Invasiveness Screening Kit. This multi-lingual decision-support tool for the risk screening of aquatic organisms provides assessors with risk scores for a species under current and future climate change conditions that, following a statistically based calibration, permits the accurate classification of species into high-, medium- and low-risk categories under current and predicted climate conditions. The 1730 screenings undertaken encompassed wide geographical areas (regions, political entities, parts thereof, water bodies, river basins, lake drainage basins, and marine regions), which permitted thresholds to be identified for almost all aquatic organismal groups screened as well as for tropical, temperate and continental climate classes, and for tropical and temperate marine ecoregions. In total, 33 species were identified as posing a ‘very high risk’ of being or becoming invasive, and the scores of several of these species under current climate increased under future climate conditions, primarily due to their wide thermal tolerances. The risk thresholds determined for taxonomic groups and climate zones provide a basis against which area-specific or climate-based calibrated thresholds may be interpreted. In turn, the risk rankings help decision-makers identify which species require an immediate ‘rapid’ management action (e.g. eradication, control) to avoid or mitigate adverse impacts, which require a full risk assessment, and which are to be r

The COVID-19 global pandemic has had severe, unpredictable and synchronous impacts on all levels of perishable food supply chains (PFSC), across multiple sectors and spatial scales. Aquaculture plays a vital and rapidly expanding role in food security, in some cases overtaking wild caught fisheries in the production of high-quality animal protein in this PFSC. We performed a rapid global assessment to evaluate the effects of the COVID-19 pandemic and related emerging control measures on the aquaculture supply chain. Socio-economic effects of the pandemic were analysed by surveying the perceptions of stakeholders, who were asked to describe potential supply-side disruption, vulnerabilities and resilience patterns along the production pipeline with four main supply chain components: a) hatchery, b) production/processing, c) distribution/logistics and d) market. We also assessed different farming strategies, comparing land- vs. sea-based systems; extensive vs. intensive methods; and with and without integrated multi-trophic aquaculture, IMTA. In addition to evaluating levels and sources of economic distress, interviewees were asked to identify mitigation solutions adopted at local / internal (i.e., farm-site) scales, and to express their preference on national / external scale mitigation measures among a set of a priori options. Survey responses identified the potential causes of disruption, ripple effects, sources of food insecurity, and socio-economic conflicts. They also pointed to various levels of mitigation strategies. The collated evidence represents a first baseline useful to address future disaster-driven responses, to reinforce the resilience of the sector and to facilitate the design reconstruction plans and mitigation measures, such as financial aid strategies.

Samples of the European eel, Anguilla anguilla from two different habitats in the River Neretva estuary region were analysed using two different traditional fishery gear, in the period from 2016 to 2019. The monthly eel catches in ten traditional fyke nets in Parila lagoon varied from 4.4 to 12.7 kg (±2.45 kg) in 2016 and 2.4 to 9.6 kg (±2.01 kg) in 2019. There were no statistical differences between monthly and total weights recorded in 2016 and 2019 (t=1.04; p=0.312). The b-coefficient of the length-weight (LW) relationship for the freshwater eel samples varied from 3,1036 to 3,3206 during two-year period of the sampling. The LW relationship for the brackish population was significantly lower (b-coefficient 2,6513). The dominant eel stage in both sites was yellow eel, while silver stage was scarce. The fishery with traditional devices revealed that efficiency of these artisanal tools is low, pointing to poor abundance of eel in their common habitats. The recorded catch using bigger traditional eel trap gear during autumn spawning migrations was also dominated with yellow stage, while silver eel represented only 15,4% of the catch. The infestation of eels with the parasite, Anguillicoloides crassus was significantly higher in freshwater habitat (41% of eel specimens infested) than in brackish, Parila lagoon (7%). Poor efficiency of traditional gear, bad length and weight structure of the population and low b-coefficients of eels in their most important habitat, indicate poor status of European eel population and River Neretva estuarine ecosystems., Europska jegulja, Anguilla anguilla analizirana je u dva različita staništa u delti Neretve pomoću dva različita tradicionalna ribolovna alata za jegulju u razdoblju od 2016. do 2019. Ulov jegulje u deset tradicionalnih vrša za jegulje u laguni Parila kolebao je mjesečno od 4,4 do 12,7 kg (± 2,45 kg) u 2016. godini i od 2,4 do 9,6 kg (± 2,01 kg) u 2019. godini. Nije bilo statističke razlike između mjesečnih i ukupnih masa zabilježenih u 2016. i 2019. godini (t = 1,04; p = 0,312). b-koeficijent odnosa duljine i mase (LW) za jegulje iz slatkovodnog područja kolebao je od 3,1036 do 3,3206 tijekom dvije godine uzorkovanja. Odnos LW za jegulje iz bočatog staništa bio je značajno niži (b-koeficijent 2.6513). Dominantni stadij jegulje u oba područja bila je žuta jegulja, dok je srebrna jegulja bila rijetka. Ribolov tradicionalnim ribolovnim alatima pokazao je da je učinkovitost ovih alata niska, što ukazuje na malu brojnost jegulja u njihovim tradicionalnim staništima. Ulovom u “trati”- tradicionalnom alatu za ulov jegulje tijekom jesenskih migracija dominirala je također žuta jegulja, sa samo 15,4% ulova srebrne jegulje. Zaraženost jegulja parazitom Anguillicoloides crassus bila je znatno veća u slatkovodnom staništu (41%), u usporedbi sa 7% jegulja iz bočate lagune Parila. Slaba ribolovna učinkovitost tradicionalnog ribolovnog alata, loša duljinska i masena struktura populacije i niski b-koeficijenti jegulja u najvažnijem staništu jegulje ukazuju na loš status populacije neretvanske jegulje i ekosustava ušća rijeke Neretve.

The COVID-19 global pandemic has had severe, unpredictable and synchronous impacts on all levels of perishable food supply chains (PFSC), across multiple sectors and spatial scales. Aquaculture plays a vital and rapidly expanding role in food security, in some cases overtaking wild caught fisheries in the production of high-quality animal protein in this PFSC. We performed a rapid global assessment to evaluate the effects of the COVID-19 pandemic and related emerging control measures on the aquaculture supply chain. Socio-economic effects of the pandemic were analysed by surveying the perceptions of stakeholders, who were asked to describe potential supply-side disruption, vulnerabilities and resilience patterns along the production pipeline with four main supply chain components: a) hatchery, b) production/processing, c) distribution/logistics and d) market. We also assessed different farming strategies, comparing land- vs. sea-based systems; extensive vs. intensive methods; and with and without integrated multi-trophic aquaculture, IMTA. In addition to evaluating levels and sources of economic distress, interviewees were asked to identify mitigation solutions adopted at local / internal (i.e., farm-site) scales, and to express their preference on national / external scale mitigation measures among a set of a priori options. Survey responses identified the potential causes of disruption, ripple effects, sources of food insecurity, and socio-economic conflicts. They also pointed to various levels of mitigation strategies. The collated evidence represents a first baseline useful to address future disaster-driven responses, to reinforce the resilience of the sector and to facilitate the design reconstruction plans and mitigation measures, such as financial aid strategies.

The rapid, global spread of COVID-19, and the measures intended to limit or slow its propagation, are having major impacts on diverse sectors of society. Notably, these impacts are occurring in the context of other anthropogenic-driven threats including global climate change. Both anthropogenic stressors and the COVID-19 pandemic represent significant economic challenges to aquaculture systems across the globe, threatening the supply chain of one of the most important sources of animal protein, with potential disproportionate impacts on vulnerable communities. A web survey was conducted in 47 countries in the midst of the COVID-19 pandemic to assess how aquaculture activities have been affected by the pandemic, and to explore how these impacts compare to those from climate change. A positive correlation between the effects of the two categories of drivers was detected, but analysis suggests that the pandemic and the anthropogenic stressors affect different parts of the supply chain. The immediate measurable reported losses varied with aquaculture typology (land vs. marine, and intensive vs. extensive). A comparably lower impact on farmers reporting the use of integrated multitrophic aquaculture (IMTA) methods suggests that IMTA might enhance resilience to multiple stressors by providing different market options under the COVID-19 pandemic. Results emphasize the importance of assessing detrimental effects of COVID-19 under a multiple stressor lens, focusing on areas that have already locally experienced economic loss due to anthropogenic stressors in the last decade. Holistic policies that simultaneously address other ongoing anthropogenic stressors, rather than focusing solely on the acute impacts of COVID-19, are needed to maximize the long-term resilience of the aquaculture sector.

The rapid, global spread of COVID-19, and the measures intended to limit or slow its propagation, are having major impacts on diverse sectors of society. Notably, these impacts are occurring in the context of other anthropogenic-driven threats including global climate change. Both anthropogenic stressors and the COVID-19 pandemic represent significant economic challenges to aquaculture systems across the globe, threatening the supply chain of one of the most important sources of animal protein, with potential disproportionate impacts on vulnerable communities. A web survey was conducted in 47 countries in the midst of the COVID-19 pandemic to assess how aquaculture activities have been affected by the pandemic, and to explore how these impacts compare to those from climate change. A positive correlation between the effects of the two categories of drivers was detected, but analysis suggests that the pandemic and the anthropogenic stressors affect different parts of the supply chain. The immediate measurable reported losses varied with aquaculture typology (land vs. marine, and intensive vs. extensive). A comparably lower impact on farmers reporting the use of integrated multitrophic aquaculture (IMTA) methods suggests that IMTA might enhance resilience to multiple stressors by providing different market options under the COVID-19 pandemic. Results emphasize the importance of assessing detrimental effects of COVID-19 under a multiple stressor lens, focusing on areas that have already locally experienced economic loss due to anthropogenic stressors in the last decade. Holistic policies that simultaneously address other ongoing anthropogenic stressors, rather than focusing solely on the acute impacts of COVID-19, are needed to maximize the long-term resilience of the aquaculture sector.

This study provides the first data on the reproductive biology of the spiny gurnard Lepidotrigla dieuzeidei. A total of 1027 individuals were collected monthly from September 2011 to August 2012. The total length of the individuals in the sample ranged from 7.46 cm to 14.62 cm with a female to male ratio of 1 to 0.59. Positive allometric growth was observed for both females (b=3.07) and males (b=3.08). Variations of condition factor were similar in both sexes with mean values of 1.07 for females and 1.01 for males. The fish L. dieuzeidei had a long spawning period extending from November to July based on monthly values of gonadosomatic index. Histological analysis showed that this fish was multiple synchronous developments of ovaries with multiple spawning events. The ovaries were always represented with a group of primary oocytes and a diverse population of vitel-logenic oocytes, each specially recruited during the final stages of maturation in uniform or uneven phases. Batch fecundity was estimated gravimetrically using the hydrated oocyte method and was estimated to be around 558 to 10.230 oocytes per female. L. dieuzeidei is an important by-catch species and data from this study represent a valuable contribution to stock management., Ovo istraživanje donosi prve podatke o reproduktivnoj biologiji kokotića, Lepidotrigla dieuzei-dei. Ukupno je prikupljeno 1027 jedinki, uzorkovano je mjesečno od rujna 2011. do kolovoza 2012. Ukupna duljina jedinki bila je u rasponu od 7,46 cm do 14,62 cm s omjerom spolova ženke:mužjaci 1:0,59. Pozitivan alometrijski rast zabilježen je i kod ženka (b = 3,07) i kod mužjaka (b = 3,08). Promjene indeksa kondicije bile su slične kod oba spola sa srednjim vrijednostima od 1,07 za ženke i 1,01 za mužjake. Temeljem mjesečnih vrijednosti gonadosomatskog indeksa utvrđeno je da kokotić ima dugo razdoblje mriješćenja, od studenog do srpnja. Histološka analiza pokazala je multipli sinkroni razvoj jajnika s više razdoblja mriješćenja. U jajnicima su uvijek bile zastupljene skupine primarnih oocita i raznovrsni stadiji vitelogenih oocita, koji su regrutirani u posljednjim stadijima sazrijevanja u jednoličnim ili neravnomjernim fazama. Fekunditet je procijenjen gravimetrijski primjenom metode hidratiziranih oocita i iznosi oko 558 do 10230 oocita po ženki. Kokotić je važna vrsta u prilovu i podatci iz ovog istraživanja predstavljaju značajan doprinos upravljanja stockom.