[ INTERNATIONAL NEWS ]
Baltic Sea herring stocks are notoriously challenging to manage, having fallen for many years in spite of tightened allowable catches. Herring stocks are part of a broader Baltic ecosystem that is in trouble for reasons beyond overfishing but which interfere with herring management at local or national levels. Estonian authorities and fishermen are frustrated by the worsening state of herring populations within Estonian waters, a decline that continues despite the fact the industry closely adheres to European Commission catch allocations. A further one-fifth reduction this year in the Commission’s allocation to Estonia only aggravates this frustration. The nation’s fishermen and fishery managers argue that the problem is the herring in the so-called red zone of
the Baltic Sea, beyond Estonian territory, which is in a bad shape, but which interacts with herring in Estonian waters. Estonian fishermen should not be punished, they argue, for poor ecosystem conditions elsewhere in the Baltic. The vital role that Baltic herring plays in Estonian culture dates back millennia; but today a large chunk of Baltic herring goes to fish farms in Norway and elsewhere. Estonians understandably object to having to pay for problems caused by other industries in other countries. However, the nation’s fishermen and managers are taking a wait-and-see approach to Commission decisions on how to balance the overall Baltic herring mismanagement with spill-over impacts on local fisheries.
Eurofish
Estonia: Herring abundance falls despite Estonia’s adherence to catch limits
Baltic herring (Clupea harengus) is the Estonian national fish and has been around the Estonian coast for about 5,000 years. Because of the brackish water conditions of the Baltic Sea, it is smaller than its Atlantic counterparts and often considered a subspecies of Atlantic herring.
Spain: New research sheds light on transmission of cancers in cockle populations Transmissible cancers in marine animals such as cockles spread through the water and form tumors in their victims. They pose no threat to humans but are deadly to the animals themselves. While they are not new—having existed for hundreds or possibly thousands of years—their genetic make-up is only now understood by scientists searching for ways to combat this destructive shellfish disease. Recently, scientists at the Wellcome Sanger Institute of the CiMUS research centre at the Universidade de Santiago de Compostela in Spain, working with colleagues in other countries, have discovered unsettling news: such cockle cancers are highly genetically unstable, with a single animal’s tumor containing cancer cells with different numbers of chromosomes—unlike “normal” cancer DNA with the same chromosome count per cell.
The cancers that affect cockles, called bivalve transmissible neoplasia (BTN), are not contagious but freely transmittable in seawater, and they affect the animal’s immune system, like leukemia does in mammals. BTN spreads throughout the body and is usually lethal to the infected animal. It has been identified so far in clams, cockles, and mussels across the world. While cockle cancers pose no threat to humans, the cancer scientists studying these cockle diseases hope that in addition to the immediate gains from saving cockle populations, the insights scientists get by learning how cockle cancer cells overcome the effects of genomic instability can help researchers understand these phenomena in all forms of cancer, including in humans.
There are over 200 living species of cockle worldwide. The study focused on the common cockle (Cerastoderma edule) which is widely distributed from Iceland in the north to Senegal in the south.
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