To find out what an animal has been eating, scientists often look at an animal's poo. Gulls feed on various types of zooplankton, small animals and plants in the water column, and the red critters in the photos below are a favourite. Many call them krill, but they're not, these are the postlarval stage of a squat lobster (Munida gregaria) which is a false crab related to hermit and half crabs. At certain times of year, usually summer, these young animals swarm at the water surface and often get stranded on the shore when the tide goes out. Adults live a more solitary existance on the sea floor! True krill are much more shrimp like and can also be washed ashore but they're much smaller and less red than Munida. In the pictures you can see washed up animals, some in water and an adult plus the results on the jetty of seagulls feasting on the squat lobsters!
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