The Pilot Fish by Romayne Dawnay (Button #11)

Once there were two pilot fish. They considered that the shark, off which they lived, was particularly unpleasant. Oln a daily basis, they deplored her habits and manners: she did not care for company, she swam too fast, had no conversation, gulped her food and spat out only the least appealing morsels for her two acolytes. They, on the other hand, were constantly leading her in the way of rare and tasty refreshment.
In spite of these terrible conditions the two pilot fish managed to raise a small and well-nourished family.
One day they spied swimmers round a small ship. "Look! Look!" or rather "Smell! Smell!" they told their shark. "Lunch and leftovers for all!"
Her fin breaking the waves, the shark made straight for the ship. The captain, however, saw her coming, and had the swimmers out of the water in short order. Worse, he took his rifle and when she came up beside the boat, shot her through the head. Dead, she dropped slowly and bloodily down into the ocean.
The pilot fish were distraught. But, fortunately, other shark smelled the blood of their sister and came to make a meal of her.
Soon enough the feasting sharks were off again, taking with them in various directions, members of the pilot fish family, who attached themselves to other itinerant retinues. As they jostled and nudged their way in, they told tales of the despicable behavior of their late hostess, and learned, to their horror, that their new providers were no better.
The shock did not last, for the pilot fish had only ever known a life of complaint and food. In no time they were back in business.