Dock Nightlife
Cape Cod’s working harbors come alive with strange creatures every night. Searching around piers after dark reveals a world of nocturnal animals like glittering squid, camouflaged sea slugs, and unnervingly speedy polychaete worms.
Powerful flashlights allow us to see clearly under the water’s surface without the glare of the sun, and some animals are even attracted to our lights.
We can use dipnets and clear observation tanks to take our time watching and photographing most animals, as long as they can be safely caught and released. Alternately, simply holding a flashlight steady in the water can be enough to watch a mesmerizing array of creatures gather in its beam.
What we'll see:
Most piers are encrusted by a dense reef-like community of algae, sponges, and bryozoans. Swimming among the stationary life are grass shrimp, seahorse-like pipefish, and in early spring, colorful sea slugs.
Nearly all trips include swimming crabs, isopods, amphipods, and a handful of species of small fish. Iridescent ctenophores or other jellies make a regular appearance. Larval horseshoe crabs and juvenile lobsters are common but seasonal. Skeleton shrimp, a skinny, praying-mantis like animal with reaper-like forelimbs, are abundant in Provincetown.
Occasional appearances are made by alien-like salps and siphonophores, which are free-floating animals that can either live independently or as part of a larger “superorganism” made up of hundreds of individuals.
In late summer, larval fish increase in abundance. On the south side of the Cape, this can include “lost” tropical species from the bizarre and needle-like houndfish to mullet and pilotfish.
Several species of squid are possible, but unpredictable and not guaranteed.
Occasionally, larger vertebrates like diamond-backed terrapins (a turtle) or small sharks are visible at piers in Wellfleet in Orleans.
The best part of these trips is we find something that surprises us nearly every time.