Today’s Weekly Sea Discovery: the Pacific Sand Lance!
Pacific Sand Lance are members of the extremely important food web group known as “Forage Fish”. You may recognize this term from recent news about another member of this group, the Pacific Herring, which has faced over-exploitation along the coast of British Columbia. Forage fish are important link in the food web between microscopic plankton and higher-level consumer species, such as marine mammals, birds and fishes. Their fatty tissue provides a high source of energy in the diet of their predators.
Not only are Pacific Sand Lance an important part of Mayne Islands subtidal ecosystem, but they also have a unique behaviour of burrowing into sandy bottoms. When not feeding in the water column, burrowing in the sand allows them to rest while hiding from predators that find them ever so tasty.
In recent years, scientists have studied whether Pacific Sand Lance have a specific type of substrate (sand, gravel, etc.) that they burrow into, and by determining this, how we can protect habitats that are essential to the sand lances. Studies have shown Pacific Sand Lance to prefer medium-coarse sand, so they are able to wiggle in without expending too much energy, but are still able to get enough oxygen from the water in between the grains.
In the winter of 2009-2010, here on Mayne Island we were able to locate spawning habitats (where sand lance lay eggs) in Campbell Bay, Horton Bay and Village Bay. By identifying these critical habitats, we can protect areas that Pacific Sand Lance need to thrive and continue to support other species in the surrounding food web such as salmon and Southern Resident Killer Whales.
Check out this video of sand lance swimming out of their burrows, they’re incredibly quick!