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Little is known of communication and perception in this species. However, northern anchovies use vision and chemoreception through nares and the lateral line system to perceive their environment and communicate with conspecifics.
Communication Channels: visual ; chemical
Perception Channels: visual ; tactile ; vibrations ; chemical
Based on research by California Department of Fish and Game (CDFG), northern anchovy landings and exploitation rates since 1983 have been decreasing. While biomass estimates are unavailable for recent years, CDFG believes the stock is currently stable at a modest biomass level. Northern anchovies are classified as a species of least concern on the IUCN's Red List of Threatened Species. Although current populations are thought to be stable, overfishing presents a potential threat to the longterm persistence of this species.
US Federal List: no special status
CITES: no special status
State of Michigan List: no special status
IUCN Red List of Threatened Species: least concern
During the larval period and throughout development, integument and lateral line system of northern anchovies develop gradually. Their eyes migrate from a binocular orientation to the sides of the head, and the digestive tract gradually becomes able to digest proteins. The swim bladder develops expansive capability via muscle differentiation, and trunk musculature differentiates and develops into two muscle fiber types. Organs development in northern anchovies can be characterized as initial differentiation followed by continued development of specialized cell and tissue types. A complete review of embryological development is provided in O'Connel, 1981.
There are no known adverse effects of Engraulis mordax on humans.
Northern anchovies support a number of commercial fisheries and live-bait fisheries in the United States, Canada, and Mexico. They are commonly consumed by humans and are sold live to anglers as bait. They are often converted into feed for fish hatcheries and farms and are a source of industrial fish meal and oil. From 1916 to 1967, catches averaged 325 metric tons per year. Total population biomass for northern anchovies was estimated to be 432,000 tons in 1994. Currently, California does not have an active fishery for this species.
Positive Impacts: food ; source of medicine or drug ; produces fertilizer
Northern anchovies are an important primary and secondary consumer within the epipelagic food web of the Pacific coast. It is a critical source of food for a great variety of organisms, such as larger fish, marine mammals, and marine birds. Larvae are an important component of the spring ichthyoplankton assemblage in coastal California. Northern anchovies are host to numerous endoparasites, including protists (e.g., myxosporidian protozoan), flatworms (e.g., hemiurid trematodes and didymozoid trematodes, and digenean flatworms), and roundworms (e.g., Anisakis and Hysterothylacium).
Commensal/Parasitic Species:
Northern anchovies feed upon krill, copepods, and decapod larvae, and collect food via filter feeding and active predation. When filter feeding, water and zooplankton pass through its large gaping mouth as it swims. Water passing over the gills is strained through long, finely-separated gill rakers, which collect particulate organic matter, phytoplankton, and zooplankton. Apart from nonselective filter feeding, northern anchovies have also been observed 'pecking' at larger prey. Adult northern anchovies typically attack prey only once and rarely make a second attempt in the event that prey escape.
Upon sighting prey, northern anchovy larvae assumes an S-shaped posture and advances toward the prey by sculling its pectoral fins and undulating the fin fold, while maintaining the S-posture. Larval anchovies maintain prey in the center of their visual field via slight adjustments in the position of its head and body. When prey are within striking distance, a larva opens its mouth and straightens its body. This causes the body to project forward, and the prey is ingested. The entire process takes about 1 to 2 seconds.
Animal Foods: zooplankton
Plant Foods: phytoplankton
Foraging Behavior: filter-feeding
Primary Diet: planktivore
Northern anchovy are found off the west coast of North America, from Queen Charlotte Islands in British Columbia, Canada, to Cabo San Lucas in Baja California, Mexico, and in the Gulf of California.
Biogeographic Regions: nearctic (Native ); pacific ocean (Native )
Engraulis mordax is a neritic, epipelagic species that favors areas of coastal upwelling. Larvae can be found from 0 to 50 meters in depth, and adults are commonly found between 70 m and 200 m in depth. Larvae, juveniles, and adults can tolerate water temperatures between 8 and 25 degrees Celsius.
Range depth: 0 to 200 m.
Average depth: 73 m.
Habitat Regions: temperate ; saltwater or marine
Aquatic Biomes: pelagic ; coastal
Little information is available concerning the average lifespan of northern anchovies. In the wild, most live between 4 and 7 years, with an average lifespan of 5 years.
Average lifespan
Status: wild: 7 years.
Typical lifespan
Status: wild: 4 to 7 years.
Average lifespan
Status: wild: 5 years.
Northern anchovies are small, slightly compressed and have large, inferior mouths. They are an iridescent bluish-green on the dorsum and shiny silver along the ventral surface. Adults have a faint silver stripe along their side. The insertion point of the anal fin can be used to distinguish northern anchovies from other anchovy species, as it inserts immediately posterior to the dorsal fin. Average adult size is 9 g in mass and 7 cm in length, and individuals rarely exceed 10 g in mass and 9 cm in length. Sexual dimorphism has not been reported in this species.
Range mass: 10 (high) g.
Average mass: 9 g.
Range length: 9.0 (high) cm.
Average length: 7.0 cm.
Other Physical Features: heterothermic ; bilateral symmetry
Sexual Dimorphism: sexes alike
Northern anchovy larvae, while transparent, fall prey to a number of invertebrate and vertebrate planktivores. As juveniles they acquire pelagic coloration, and are extremely vulnerable to piscivores such as albacore and chub mackeral. A wide variety of fish, seabirds, and marine mammals feed on northern anchovies. They form large schools for protection against predators, and their coloration may help camouflage them from potential predators. Humans are probably the most significant predator of northern anchovies.
Known Predators:
Anti-predator Adaptations: cryptic
Northern anchovies are promiscuous, as both sexes spawn indiscriminately with multiple partners during breeding season.
Mating System: polygynandrous (promiscuous)
Northern anchovies breed during late winter and spring, however, some research suggests that they spawn throughout the year, with peak activity occurring from February to April. Spawning usually occurs within 95 km of the coast, but has been recorded up to 480 km offshore. There are approximately 574 eggs per gram, and fertilized eggs hatch 2 to 4 days after spawning. Northern anchovies perform seasonal migrations, usually moving to deeper, offshore waters during winter, and returning to shallow, coastal waters for spring. Males and females become sexually mature at about 2 years of age.
Breeding season: Throughout the year, with peaks between February to April.
Range number of offspring: 20,000 to 30,000.
Range gestation period: 2 to 4 days.
Average age at sexual or reproductive maturity (female): 2 years.
Average age at sexual or reproductive maturity (male): 2 years.
Key Reproductive Features: year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (External ); broadcast (group) spawning; oviparous
Northern anchovies are broadcast spawners, and therefore, parental care is nonexistent in this species.
Parental Investment: no parental involvement
