Fish farming on land versus fish farming in the sea

„Why are fish so indif­fe­rent to us?“ – this ques­ti­on is asked by repor­ter Han­nes Jae­ni­cke in the ZDF docu­men­ta­ry „Im Ein­satz für den Lachs“ (Ger­man). The report and its con­tent have been the sub­ject of much dis­cus­sion in the media and in socie­ty in recent weeks. From our point of view, this is a very important topic, becau­se the docu­men­ta­ti­on shows the fatal con­se­quen­ces of mass live­stock far­ming in so-cal­led sal­mon farms in net cages for the natu­ral wild sal­mon stocks and the eco­sys­tem. The sal­mon is one of the most popu­lar edi­ble fish in the world, and no one real­ly wants to live wit­hout it. But less of the sal­mon that end up on our pla­tes are wild cat­ches. Rea­ring in aquacul­tures could be the solu­ti­on to con­ti­nue pro­du­cing popu­lar fish spe­ci­es in lar­ge quan­ti­ties. Alt­hough many peo­p­le are awa­re of the over­fi­shing of the oce­ans and the neces­si­ty of fish far­ming, very few know the advan­ta­ges and dis­ad­van­ta­ges of dif­fe­rent aquacul­tu­re sys­tems. In the fol­lo­wing, we will go into the dif­fe­ren­ces using the exam­p­le of salmon.

The con­sump­ti­on of fish and its consequences

It is esti­ma­ted that Ger­mans con­su­me more than 14 kilo­grams of fish per year. Alas­ka pol­lack and sal­mon are among the most popu­lar edi­ble fish. As a result, the­se par­ti­cu­lar­ly end­an­ge­red fish spe­ci­es, among many others, have beco­me a mass pro­duct. In the ref­ri­ge­ra­ted shel­ves of super­mar­kets, sal­mon can be found in all pos­si­ble forms: whe­ther who­le, as fresh fil­lets, smo­ked or in sushi. Jae­ni­cke puts it quite dra­sti­cal­ly: „The big­gest pro­blem is our insa­tia­ble appe­ti­te for fish. In Cana­da, the natu­ral habi­tat of the sal­mon, the stocks in the waters have been redu­ced con­sider­a­b­ly. In the past, inha­bi­tants, bears and sea eagles could feed on hundreds of thou­sands of sal­mon, but this is no lon­ger pos­si­ble today, as the inter­na­tio­nal indus­try demands seve­ral mil­li­on tons of sal­mon annually.”

The pro­blems of net cages

In prin­ci­ple, spe­ci­es-appro­pria­te and sus­tainable rea­ring in aquacul­tu­re sys­tems can con­tri­bu­te to the con­ser­va­ti­on of natu­ral stocks. Howe­ver, the­re are enorm­ous dif­fe­ren­ces with regard to the dif­fe­rent rea­ring methods. A descrip­ti­on of dif­fe­rent aquacul­tu­re forms is available in our blog post “Open aquacul­tu­re sys­tems“. The ZDF docu­men­ta­ry takes a clo­ser look at the rea­ring of sal­mon in Nor­way in net cages. Net pens or cage sys­tems are ancho­red in natu­ral waters such as ponds, rivers or the open sea. Alt­hough the spa­ti­al limi­ta­ti­on faci­li­ta­tes fee­ding, con­trol and fishing, this form of rea­ring also cau­ses some pro­blems. The ani­mals are not reared in a spe­ci­es-appro­pria­te way in a con­fi­ned space. At the same time, meta­bo­lic pro­ducts of the fish, food remains and often admi­nis­te­red drugs such as anti­bio­tics reach the sur­roun­ding waters direct­ly. Bio­lo­gi­cal dead zones deve­lop under­neath the net farms. Infe­sta­ti­on with viru­s­es and para­si­tes is also a major pro­blem in such cage sys­tems due to the high sto­cking den­si­ties and lack of cur­rent. Dise­a­ses and defor­ma­ti­ons of the ani­mals occur in a very con­fi­ned space. Dead fish are not fished out of the lar­ge mas­ses but sink to the bot­tom and con­ta­mi­na­te the water the­re as „bac­te­ria slingshot“. If you look at the­se cir­cum­s­tances clo­se­ly, it is high­ly ques­tionable whe­ther fish from such faci­li­ties can be eaten with appe­ti­te at all.

Aquacul­tu­re can also be envi­ron­men­tal­ly friendly

By rea­ring fish in recir­cu­la­ti­on sys­tems on land, sus­taina­bi­li­ty can be signi­fi­cant­ly increased. The­se clo­sed sys­tems have enorm­ous advan­ta­ges com­pared to other forms of aquaculture:

• Avo­id­ance of nega­ti­ve effects on the envi­ron­ment by kee­ping the sys­tem closed
• Ener­gy saving through effi­ci­ent design of the technology
• Water saving thanks to powerful water tre­at­ment and
• Rem­oval of feed resi­dues, excre­ments and meta­bo­lic pro­ducts by mecha­ni­cal and bio­lo­gi­cal filters
• Suf­fi­ci­ent habi­tat for the ani­mals by fixed sto­cking den­si­ties, which result from the exis­ting water volume
• Safe­guar­ding ani­mal wel­fa­re through auto­ma­tic con­trol and per­ma­nent moni­to­ring of all the important parameters

The­se advan­ta­ges are also com­bi­ned in the SEAWATER Cube, with which we would like to con­tri­bu­te to the pro­tec­tion of natu­ral stocks and enable sus­tainable, high-qua­li­ty and regio­nal fish far­ming under con­trol­led con­di­ti­ons. In our faci­li­ty we com­ple­te­ly dis­pen­se medi­ca­ti­on and growth pro­mo­ters with the use of machi­nes. SEAWATER Fish grows up with suf­fi­ci­ent space in clear water. As soon as the fish are rea­dy to be sold, they are fished fresh by hand only after recei­ving the customer’s order. In this way, we gua­ran­tee both a gent­le and needs-based rem­oval from the tank as well as an excep­tio­nal fresh­ness of our pro­ducts and avo­id rejects completely.

Qua­li­ty ins­tead of quantity

In sum­ma­ry, we can sta­te that the cla­im for fish con­sump­ti­on must also be „Less is more, but in high qua­li­ty“. When choo­sing fish pro­ducts, it should be ensu­red that they ide­al­ly come from respon­si­bly mana­ged and clo­sed recir­cu­la­ti­on sys­tems. Alt­hough excep­tio­nal qua­li­ty is also asso­cia­ted with a hig­her pri­ce, we can pro­tect not only our health, but also our earth through sus­tainable, regio­nal and con­scious con­sump­ti­on. Each indi­vi­du­al should make his or her own con­tri­bu­ti­on to the over­all suc­cess and how could it be easier than start­ing here with the topic of food, which accom­pa­nies us every day.