Fish & Water - Sounds Wild
Sand Lance

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Sand Lance

Early on a summer morning a horde of gulls is busy on a sandy beach exposed at low tide. They’re foraging on Pacific sand lance - thin, eel-like fish just a few inches long that hide in the soft, wet sand. Bonaparte’s gulls spot subtle signs of the little fish in the sand, and neatly pull them out by the head; bigger glaucous winged gulls jab at the sand and steal fish from other gulls.

Last night, when this beach was submerged under the high tide, sand lance burrowed into the clean, loose sands. Normally during the day, when sandy areas like this are under water, the little fish emerge and form large schools that forage on fish larvae, copepods, and other small invertebrates. Cod, salmon and humpback whales feed on the schools of free-swimming sand lance, as do terns, puffins and cormorants. Sand lance are safer from predators when hiding in their sandy burrows, but not entirely safe, as we see today. As might be expected for a fish that can be found under exposed sand on beaches at low tide, sand lance can tolerate low oxygen levels and wide swings in temperature and salinity.

Even when their sandy hideaways are submerged underwater, sand lance aren’t entirely safe from predators. Humpback whales forage on buried sand lance by bottom feeding in the style of grey whales – they dredge their faces through the silt and sand on the seafloor, and use their baleen to filter the food. Whales that do this develop characteristic rub marks on the side of their mouth and face.