[dropcap]M[/dropcap]igrant fish stocks, like salmon and trout, have long been diminishing worldwide. Introducing fish eggs into natural reproduction habitats in rivers is one way to recreate a self-sustaining population of migrant fish. Typically this has been done using plastic boxes which are expensive and difficult to recover from the fast-flowing rapids in rivers.
Now, this has been made more ecological and less expensive with a new biodegradable fish egg box made of Stora Enso’s paperboard by the packaging manufacturer Pyroll Oy. The idea was created by the Finnish ichtyologist and fish farmer Manu Vihtonen.
The paperboard boxes will decompose naturally, eliminating the need for the laborious egg box recovery. A 200 ml box can accommodate 1 000-2 000 salmon or trout eggs and, as confirmed in trials, 95-98% of them will hatch.
Paperboard fish egg boxes have been sent for testing to Iceland and Argentina, and they could become a global way of helping fish stocks to revive.