UČINAK SUSTAVA ZA TRETIRANJE VODENOG BALASTA NA PREŽIVLJAVANJE PRIRODNIH POPULACIJA ZOOPLANKTONA U PLOVIDBENIM UVJETIMA NA BRODU „NAŠE MORE“

Introdukcija alohtonih vrsta predstavlja vrlo opasnu prijetnju svjetskoj bioraznolikosti. Više je vektora unosa morskih alohtonih vrsta u nova staništa, a najizraženiji su akvakultura i brodski promet, tj. obraštaj na oplati broda i vodeni balast. U ovom radu opisano je testiranje sustava za obradu vodenog balasta u plovidbenim uvjetima na brodu „Naše more“ u Šibenskom zaljevu i Omišaljskoj uvali. Određivao se učinak ciklonske separacije u hidrociklonu, zasebno i u kombinaciji s ultraljubičastim zračenjem u UV reaktoru, na preživljavanje zooplanktonskih organizama. Morska voda je usisavana brodskom pumpom i propuštana zasebno kroz hidrociklonski klaster, te kombinirano kroz hidrociklonski klaster i UV reaktor u 3 uzastopna ciklusa. Dobiveni su gotovo identični rezultati u pokusima s UV zračenjem kao i pokusima bez UV zračenja, što ukazuje na zadovoljavajuću učinkovitost mehaničkog tretiranja u hidrociklonu na preživljavanje zooplanktona. Prikupljeni su i analizirani kontrolni uzorci iz okolnog mora, uzorci separirani hidrociklonima kao i oni koji su prošli kroz sustav za tretiranje i sakupljeni u tankove na brodu koji su predstavljali balastne tankove. Usporedbom kontrolnih uzoraka iz okolnog mora i tretiranih uzoraka iz tankova na brodu zaključeno je da je ciklonskom separacijom odstranjeno 62,7 % do 54,5 % organizama, što znači da je u pokusima kroz hidrociklone propušteno i sakupljeno u tankove na brodu 37,3 % do 45,5 % jedinki, od čega je bilo 4,7 % do 32,8 % živih. Nakon 8 sati udio živih jedinki u odnosu na ukupni broj u okolnom moru bio je 14,9 %, a nakon 24 sata svega 1,8 %. Provedenim pokusima dokazana je i razrađena uspješna upotreba sustava za obradu vodenog balasta za inaktivaciju zooplanktonskih organizama u morskoj vodi

UČINAK SUSTAVA ZA TRETIRANJE VODENOG BALASTA NA PREŽIVLJAVANJE PRIRODNIH POPULACIJA ZOOPLANKTONA U PLOVIDBENIM UVJETIMA NA BRODU „NAŠE MORE“

Introdukcija alohtonih vrsta predstavlja vrlo opasnu prijetnju svjetskoj bioraznolikosti. Više je vektora unosa morskih alohtonih vrsta u nova staništa, a najizraženiji su akvakultura i brodski promet, tj. obraštaj na oplati broda i vodeni balast. U ovom radu opisano je testiranje sustava za obradu vodenog balasta u plovidbenim uvjetima na brodu „Naše more“ u Šibenskom zaljevu i Omišaljskoj uvali. Određivao se učinak ciklonske separacije u hidrociklonu, zasebno i u kombinaciji s ultraljubičastim zračenjem u UV reaktoru, na preživljavanje zooplanktonskih organizama. Morska voda je usisavana brodskom pumpom i propuštana zasebno kroz hidrociklonski klaster, te kombinirano kroz hidrociklonski klaster i UV reaktor u 3 uzastopna ciklusa. Dobiveni su gotovo identični rezultati u pokusima s UV zračenjem kao i pokusima bez UV zračenja, što ukazuje na zadovoljavajuću učinkovitost mehaničkog tretiranja u hidrociklonu na preživljavanje zooplanktona. Prikupljeni su i analizirani kontrolni uzorci iz okolnog mora, uzorci separirani hidrociklonima kao i oni koji su prošli kroz sustav za tretiranje i sakupljeni u tankove na brodu koji su predstavljali balastne tankove. Usporedbom kontrolnih uzoraka iz okolnog mora i tretiranih uzoraka iz tankova na brodu zaključeno je da je ciklonskom separacijom odstranjeno 62,7 % do 54,5 % organizama, što znači da je u pokusima kroz hidrociklone propušteno i sakupljeno u tankove na brodu 37,3 % do 45,5 % jedinki, od čega je bilo 4,7 % do 32,8 % živih. Nakon 8 sati udio živih jedinki u odnosu na ukupni broj u okolnom moru bio je 14,9 %, a nakon 24 sata svega 1,8 %. Provedenim pokusima dokazana je i razrađena uspješna upotreba sustava za obradu vodenog balasta za inaktivaciju zooplanktonskih organizama u morskoj vodi

Overcoming Ostrea edulis seed production limitations to meet ecosystem restoration demands in the UN decade on restoration

The European flat oyster, Ostrea edulis, is a habitat-forming bivalve which was historically widespread throughout Europe. Following its decline due to overfishing, pollution, sedimentation, invasive species, and disease, O. edulis and its beds are now listed as a threatened and/or declining species and habitat by OSPAR. Increasing recognition of the plight of the oyster, alongside rapidly developing restoration techniques and growing interest in marine restoration, has resulted in a recent and rapid growth in habitat restoration efforts. O. edulis seed supply is currently a major bottleneck in scaling up habitat restoration efforts in Europe. O. edulis has been cultured for centuries, however, research into its culture declined following the introduction of the Pacific oyster, Crassostrea gigas to Europe in the early 1970 s. Recent efforts to renew both hatchery and pond production of O. edulis seed for habitat restoration purposes are hampered by restoration project timelines and funding typically being short, or projects not planning appropriately for the timescales required for investment, research-and-development and delivery of oyster seed by commercial producers. Furthermore, funding for restoration is intermittent, making long-term commitments between producers and restoration practitioners difficult. Long-term, strategic investment in research and production are needed to overcome these bottlenecks and meet current ambitious restoration targets across Europe

Ten priority questions for increasing the consistency and success in hatchery production of the European flat oyster for habitat restoration

The European flat oyster, Ostrea edulis, once formed extensive reef habitats throughout European seas and estuaries. These reefs are now largely functionally extinct, yet interest and support for their restoration is rapidly growing. A major bottleneck to scaling up oyster reef restoration is the lack of available oysters to supply the growing demand. This study aimed to identify the ten questions which, if answered, would increase the consistency and success in hatchery production of O. edulis for habitat restoration. Candidate questions were submitted by representatives from twelve commercial and research hatcheries across Europe. The list of 98 candidate questions were collaboratively discussed by experts from nine research hatcheries across eight countries in Europe, to identify the top ten questions via an iterative and open process. Questions were grouped into the following themes: conditioning and feeding, larval rearing, disease and water quality, hatchery protocol, genetics, and hatchery management. There were several overarching topics spanning these themes, including diet optimisation, maximising the effective population size, and developing the technical skillbase in order to increase hatchery production to meet the projected increase in demand for oyster seed for habitat restoration efforts. We anticipate this list will provide a starting point for collaborative research efforts across Europe, as well as assisting policy makers and funders in identifying key knowledge gaps

Site selection for European native oyster (Ostrea edulis) habitat restoration projects: An expert‐derived consensus

1. The European native oyster (Ostrea edulis) is a threatened keystone species which historically created extensive, physically complex, biogenic habitats throughout European seas. 2. Overfishing and direct habitat destruction, subsequently compounded by pollution, invasive species, disease, predation and climate change have resulted in the functional extinction of native oyster habitat across much of its former range. 3. Although oyster reef habitat remains imperilled, active restoration efforts are rapidly gaining momentum. Identifying appropriate sites for habitat restoration is an essential first step in long-term project success. 4. In this study, a three-round Delphi process was conducted to determine the most important factors to consider in site selection for European native oyster habitat restoration projects. 5. Consensus was reached on a total of 65 factors as being important to consider in site selection for European native oyster habitat restoration projects. In addition to the abiotic factors typically included in habitat suitability models, socio-economic and logistical factors were found to be important. Determining the temporal and spatial variability of threats to native oyster habitat restoration and understanding the biotic factors present at a proposed restoration site also influence the potential for project scale-up and longevity. 6. This list guides site selection by identifying: a shortlist of measurable factors which should be considered; the relevant data to collect; topics for discussion in participatory mapping processes; information of interest from the existing body of local ecological knowledge; and factors underpinning supportive and facilitating regulatory frameworks

Site selection for European native oyster ( Ostrea edulis ) habitat restoration projects: An expert‐derived consensus

The European native oyster (Ostrea edulis) is a threatened keystone species which historically created extensive, physically complex, biogenic habitats throughout European seas. Overfishing and direct habitat destruction, subsequently compounded by pollution, invasive species, disease, predation and climate change have resulted in the functional extinction of native oyster habitat across much of its former range. Although oyster reef habitat remains imperilled, active restoration efforts are rapidly gaining momentum. Identifying appropriate sites for habitat restoration is an essential first step in long-term project success. In this study, a three-round Delphi process was conducted to determine the most important factors to consider in site selection for European native oyster habitat restoration projects. Consensus was reached on a total of 65 factors as being important to consider in site selection for European native oyster habitat restoration projects. In addition to the abiotic factors typically included in habitat suitability models, socio-economic and logistical factors were found to be important. Determining the temporal and spatial variability of threats to native oyster habitat restoration and understanding the biotic factors present at a proposed restoration site also influence the potential for project scale-up and longevity. This list guides site selection by identifying: a shortlist of measurable factors which should be considered; the relevant data to collect; topics for discussion in participatory mapping processes; information of interest from the existing body of local ecological knowledge; and factors underpinning supportive and facilitating regulatory framework