This fish's blood has a counter-current heat exchange system that allows it to stay warm in colder, deeper water

Taxonomic description

• Has a large, robust body that is slightly compressed from side to side. ^[1]
• Back is metallic dark blue, lower sides and belly is whitish, yellow fins and lateral iridescent blue band runs along sides of live individuals. ^[1]
• Distinguished from yellowfin tuna by its bigger eyes and black-edged finlets. ^[1]
• Usually weighs 20-200 lbs. ^[2]

Distribution

• Found in tropical and temperate waters of the Atlantic, Indian, and Pacific Oceans. ^[2]

Life history

• Lives seven to nine years and matures between three and four years. ^[2]
• Spawns year-round in tropical waters, seasonally in temperate waters. ^[2]
• Releases 3-6 million eggs during spawning! ^[2]
• Eggs have oily coatings in order to float until hatched, about 24 hours after fertilization. ^[2]

Habitat

• Migratory, and will school with other tuna species at ocean surface. ^[2]
• Moves to deeper waters at night, has eyes adapted to low light levels and can regulate body temperature. ^[2]
• Feeds on fishes, cephalopods, and crustaceans. ^[1]
• Preyed on by larger tuna, billfish, toothed whales, and sharks. ^[2]

After a historic low level in 2004, Eastern Pacific bigeye tuna populations have been increasing and are now above target population levels!

Seasonal availability

• Available year-round. ^[3]

Regulatory and management authority

• Internationally overseen by the Inter-American Tropical Tuna Commission (IATTC) and the Western and Central Pacific Fisheries Commission (WCPFC). ^[3]
• Along the Pacific West Coast, the fishery is overseen by NOAA fisheries and, as established by the Magnuson-Stevens Act, the Pacific Fishery Management Council through the West Coast Highly Migratory Species Fisheries Management Plan. ^[3,4]
• As established by the Marine Life Management Act, the California Department of Fish and Wildlife (CDFW) collects data on this fishery through the Pelagic Fisheries and Ecosystem Program. ^[5,6]

Gear type

• Caught by purse seine, longline and handlines, and hook-and-line. ^[3]

Status of the fishery

• The three Pacific stocks, monitored closely by governing authorities, were deemed not to be overfished and  not subject to overfishing . ^[3]

Potential ecosystem impacts

• Fishing gear rarely contacts the seafloor, so there are minimal habitat impacts. ^[3]
• Management measures, training programs, and observer programs are required for American fishermen to minimize the impact of bycatch. ^[3]

Although "Ahi" refers to both bigeye and yellowfin tuna, bigeye has a higher fat content and is typically preferred by sashimi lovers!

Edible portions

• Typically only the meat is consumed, but the rest of the fish can also be utilized. ^[2]

Description of meat

• Firm and moist with a mild, meaty flavor and reddish-pink color that has large flakes when cooked. ^[2]

Culinary uses

• Enjoy it raw, baked, broiled, grilled, sautéed, or smoked! ^[2]
• For a tuna nigiri recipe, visit Izzy Cooking. ^[7]
• For a Spanish tuna meatball recipe, visit Luxe Gourmets. ^[8]

Nutritional information

• Information for 100g of bigeye tuna shown on table at the right. ^[3]
• Bigeye tuna is a good source of Omega-3! ^[3]

Toxicity report

• As bigeye tuna may have mercury, recommended servings depend on age and gender. ^[3]

Seasonal availability

• Available year-round. ^[3]

The Bat Ray's teeth form as flat plates and grow continuously, like its shark cousins

Taxonomic description

• Black or brown back with a white belly. ^[2]
• Has a long, thin tail with a stinger behind its dorsal fin at the base of its tail. ^[2,16]
• Has a distinctive protruding head and bat-like “wings” for propulsion through the water. ^[2]
• Females can grow up to 2 m (6 ft) across and weigh 90 kg (200 lbs); males are smaller with the largest caught at about 1 m (3 ft) across and 17 kg (37 lbs). ^[1,7]

Distribution

• Found in the Eastern Pacific, from Oregon to Mexico. ^[2,13]

Life history

• Lives up to 23 years solitarily or in schools; females aggregate during mating in the spring/summer. ^[1,9,16]
• Before mating, the male swims behind the female to detect chemical signals that indicate her reproductive status; during mating, the male swims underneath the female. ^[16]
• Reproduces via live birth. ^[16]
• Litter size of two to ten pups, with a gestation period of nine to twelve months. ^[1]

Habitat

• Lives in the intertidal to max depth of 180 meters (590 ft); with nurseries in shallow waters of bays and sloughs. ^[13]
• Prefers flat sandy seafloor with rocks. ^[1,2]
• Burrows with its snout and flaps its wings to uncover mollusks, crustaceans and small fish prey on the sandy seafloor; other fish take advantage of this behavior to find “leftovers” in the pit that is formed. ^[1]
• Its predators include sea lions, white sharks, broadnose sevengill sharks and humans through sportfishing or incidental catch in commercial fisheries. ^[1,6,13]
• Previously thought to disturb oyster fields, but it was recently discovered that bat rays eat crabs, a primary predator of oysters. ^[1]

Also known as the “Mud Marlin” by anglers because of the level of difficulty required to catch it. This fish's fighting ability is one of the main draws for sport fishing of bat rays

Seasonal availability

• Available year round, but catch is lowest in spring in southern California. ^[4,13]

Regulatory and Managing authority

• As established by the Marine Life Management Act, the California Fish and Game Commission (CFGC) regulates the fishery, and the California Department of Fish and Wildlife (CDFW) manages this fishery in state waters. ^[8,15]
• As bat ray is not a commercially targeted species, there are currently no formal management plans in place but this fishery is monitored. ^[15]
• The Groundfish Collective combines input from the industry and government entities to inform regulatory and management measures for this fishery. ^[18]

Gear type

• The best baits to use are squid or mackerel, fresh or frozen. ^[2,3,14]
• Caught by troll, longline, gillnet, hook and line, and trawl (with limited entry). ^[12]

Status of the fishery

• Although not specifically regulated, but restrictions on entry and gear (e.g. nearshore gillnets) provide protection. ^[13]
• Stocks are considered stable and increasing; it has an IUCN status of “Least Concern” since 2006. ^[13]
• Fishing for bat ray as a pest of oyster beds was virtually eliminated by 1994. ^[13]
• There is little abundance information; catch increased from 47% to 68% of fishing derby catch from the 1950s to 90s. ^.[13]

Potential ecosystem impacts

• Most of the incidental catch of rays is from trawling, which is regulated through limited entry. ^[12]

Rays and skates are seen as “trash fish” in America, but in France they are viewed as a delicacy.

Edible portions

• Usually only the wings are eaten (entire wing cut into filets). ^[11]

Description of meat

• The meat is tender but meaty; similar to skate. ^[11]
• It has been compared to white fish and scallops. ^[10,5]

Culinary uses

• Available whole or skinned and filleted, fresh or frozen. ^[10]
• If preparing fresh-caught, remove slime by rubbing the wing down with coarse salt or a scrub brush in the sink, slice meat off cartilage, filet like fish, brine, and age filets in fridge for a few days. ^[11]
• Prepare as you would any other fish, but recommend cooking methods are sautéing, deep-frying or poaching. ^{[10, 11]}
• For a Singaporean and Malaysian recipe for barbequed sambal sting ray,

Nutritional information 

• Nutrition Facts table given for skate (similar to rays). ^[17]

Toxicity report

• As the bat ray processes urea through its skin, it can develop an ammonia smell if handled improperly. Avoid buying pieces that smell like ammonia and when sport fishing, eliminate gut immediately after obtaining and put on ice. ^[10,11]

Seasonal availability

• This fish is available year round. ^[13]