Hints: patch krill Albatross black-browed 40%

Birds dispersed over its vast surface face a huge problem in finding food, for it is by no means uniformly spread throughout the ocean. The nutrients occur in patches, and so the krill, which is sustained by those nutrients, is patchy too. But once the birds find a swarm, there is a frenzy of feeding.
Krill typically spends the day in deep water, rising nearer to the surface at night. But sometimes, a swarm rises during the day and then the birds get their chance. But getting to the krill is still a major problem to all birds except penguins. Albatrosses such as the black-browed whose diet is about 40% krill can only dive down a couple of meters at the most.

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