Eel fat stores are enough to reach the Sargasso

It has long been assumed that the European eel(Anguilla anguilla) migrates to the Sargasso sea —a region of the Atlantic ocean between the Azores and the West Indies— to spawn. During the past decade, however,the number of glass eels has inexplicably dropped, and it has been suggested that a shortage of fat storage in adults, resulting from diminished food resources for juveniles in inland waters, may prevent the starving silver eels from reaching the spawning grounds. But we find that the energetic cost of the 6000-km migration is actually quite low, with 60% of the fat storage remaining available for the developing gonads.

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