Fish Active day and night

Bay Anchovy

Anchoa mitchilli

iNaturalist Wikipedia

The unsung hero of the Atlantic coast, this shimmering, translucent fish forms the massive schools that fuel the entire marine ecosystem.

0 Sightings

0 Habitats

Quick Identification

straighten

Size

Typically 6 to 10 cm (2.4 to 4 inches) in length; maximum weight is approximately 5 to 8 grams (0.2 to 0.3 oz).

palette

Colors

Translucent greenish-gray body with a distinct, bright silvery lateral stripe running from the gill to the tail.

visibility

Key Features

Translucent, slender body
Prominent silvery lateral stripe
Large mouth extending well past the eye
Deeply forked tail fin

When You’ll See Them

schedule

Activity pattern Active day and night

brightness_5

Peak hours Dawn and dusk (crepuscular feeding peaks)

calendar_month

Season May-October

restaurant

Diet A specialized filter feeder that consumes zooplankton, particularly copepods, mysids, and small invertebrate larvae.

park

Habitat Estuaries, coastal bays, salt marshes, and brackish rivers with muddy or sandy bottoms.

public Geographic range

Where Does the Bay Anchovy Live?

The Bay Anchovy is native to the western Atlantic Ocean, where it is one of the most abundant vertebrate species. Its range spans from the coastal waters of Maine in the United States, stretching southward along the entire Atlantic seaboard to the Florida Keys. The population continues through the Gulf of Mexico and down to the Yucatan Peninsula, making it a ubiquitous presence in North American estuaries and shallow coastal shelf waters.

Basemap © OpenStreetMap contributors

3 Countries

2.8M km² Range

Least Concern Conservation

US United States MX Mexico CA Canada

eco

iNaturalist / Verified observation data

View on iNaturalist open_in_new

Explore more Fish arrow_forward

Behavior

Bay Anchovies are highly social, schooling fish that spend their lives in constant motion. By forming massive, shimmering clouds of thousands of individuals, they use 'shoal defense' to confuse predators. They are a vital link in the coastal food web, serving as the primary energy source for popular game fish like Striped Bass, Bluefish, and Weakfish. Their movements are largely dictated by the tides and the seasonal temperature of the water.

These fish are also known for their incredible tolerance to varying salinity levels, allowing them to swim from the salty ocean into almost completely fresh river water. While they are generally shy and easily spooked by shadows or vibrations, they can sometimes be seen 'boiling' at the water's surface when being chased from below. They do not interact with humans directly but are a key indicator of a productive and healthy estuarine environment.

photo_camera EverydayEarth exclusive

Camera Tips

To capture the elusive Bay Anchovy on an underwater backyard or dock camera, you need to focus on lighting and frame rates. Because these fish are nearly translucent and move very quickly, they can easily appear as mere blurs. Use a camera capable of recording at 60 frames per second (fps) or higher to freeze their movement. Positioning your camera in shallow, brackish water near a structure like a dock piling or a submerged rock will give the fish a point of reference to school around.

One of the most effective ways to attract Bay Anchovies to your lens is through 'light baiting' at night. Submerge a green or white LED light near your camera; this light attracts clouds of microscopic zooplankton, which in turn draws the anchovies in for a feeding frenzy. Angle your camera so it is looking slightly upward toward the surface to capture the silver flash of their lateral stripes reflecting the light.

Pay close attention to the tide cycles in your area. Bay Anchovies often follow the rising tide into shallow marsh creeks and retreat to deeper channels as the tide falls. Set your camera in a tidal pool or a narrow creek mouth during the incoming tide for the best chance at seeing large schools. In the summer months, be sure to clean your camera lens regularly, as the nutrient-rich water these fish inhabit causes rapid algae buildup that can ruin your footage.

Similar Species

Species that look similar or are commonly confused with Bay Anchovy.

Striped Anchovy

The Striped Anchovy is generally larger and has a much more brilliant, mirror-like silver stripe that is less translucent than the Bay Anchovy's.

Atlantic Silverside

Silversides have a smaller mouth that does not extend past the eye and possess two separate dorsal fins, while the Bay Anchovy has only one.

Browse all Fish arrow_forward

Frequently Asked Questions

Bay Anchovies are active 24 hours a day, but they show significant peaks in activity during dawn and dusk. During these times, they move toward the surface to feed on zooplankton that migrate vertically in the water column.

If you live on a coastal canal or estuary, the best way to attract them is by using a submersible 'snook light' or underwater LED. The light attracts the plankton they eat, bringing the fish directly to your dock.

They are primary consumers that eat zooplankton. They use their large mouths and gill rakers to filter tiny crustaceans like copepods and small shrimp larvae out of the water.

Yes, they are extremely common in suburban coastal areas, especially around boat docks, canals, and salt marsh edges where there is protection from larger predators.

While both are small and silver, the Bay Anchovy has a much larger mouth that extends well past its eye, and its body is more translucent. Silversides have two distinct dorsal fins, whereas the anchovy has only one.

Record Bay Anchovy at your habitat

Connect a camera to start building your own species record — AI identifies every visitor automatically.

Join free Identify a photo