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Green Sturgeon fish identification, its habitats, characteristics, fishing methods.
The green sturgeon is a primitive, bottom dwelling fish characterized by its large size and long round body.
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Green sturgeons, Acipenser medirostris, also known as Sakhalin sturgeon or Sterlyad sturgeon, are highly migratory fish in the ocean. They are the most broadly distributed, wide-ranging, and most marine-oriented species of the sturgeon family. Sturgeons are widely distributed in North America and Eurasia. They ranges in Aleutian Islands and the Gulf of Alaska to Ensenada, Mexico in marine waters, and is observed in bays and estuaries up and down the west coast of North America and Canada.
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Description
There are four sensory barbels located in front of its large siphon-shaped, protrusible, toothless mouth located on the bottom (ventral) side of the head. Although they are members of the class of bony fishes, the skeleton of sturgeons is composed mostly of cartilage. The sturgeon has no scales, instead it has five rows of characteristic scutes (bony plates) located along their bodies. Scutes are actually large modified scales that serve as a type of armor or protection.
Distinguish Characteristics
- Dorsal fin soft rays: 33–36
- Anal fin soft rays: 22–28
- 8-11 dorsal scutes
- 23-30 lateral scutes
- 7-10 ventral scutes
- Single row of 1 to 4 bony plates along the midventral line between the anus and the anal fin
- 1-2 large scutes trailing the dorsal fin and behind the anal fin
- Max length: 250 cm
- Max weight: 159 kg
- Max age: 70 years
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Green sturgeon have 8-11 scutes on their back (dorsal) located in front of a single dorsal fin, 1-2 large scutes trailing the dorsal fin, as well as behind the anal fin, 23-30 scutes along the lateral side, and 7-10 scutes on the ventral bottom side. Dorsal arises at posterior third of the total length; anal fin arises under posterior part of dorsal; pectorals originate low on the body just behind gill opening and are large and rounded; pelvic fins arise near the anus. The backbone of the sturgeon curves upward into the caudal fin, forming their shark-like tail.
The dorsal body color is a dark olive-green with the ventral surface a lighter whitish green, and with the scutes having a lighter coloration than the body. Their fins are grayish to pale green. Longitudinal olive-green stripes, one is on the side between lateral and ventro-lateral plates, and another one on midventral surface. Green sturgeon is long-lived, slow-growing fish and the most marine-oriented of the sturgeon species. Mature males range from 4.5-6.5 feet (1.4-2 m) in fork length and do not mature until they are at least 15 years old, while mature females range from 5-7 feet (1.6-2.2 m) fork length and do not mature until they are at least 17 years old. Maximum ages of adult green sturgeon are likely to range from 60-70 years. Maximum length for green sturgeon is 7 feet (250 cm) and weigh up to 350 pounds (159 kg).
Green sturgeon is similar in appearance to white sturgeon, except the barbels are closer to the mouth than the tip of the long, narrow snout. Also they have different number of bony plates on dorsal and lateral rows. There is one large scute behind the dorsal fin and 1 behind the anal fin in Green sturgeon (both lacking in white sturgeon). The scutes also tend to be sharper and more pointed than in white sturgeon.
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Habitats
Green sturgeon utilize both freshwater and saltwater habitat; they rely on streams, rivers, and estuarine habitat as well as marine waters during their lifecycle. Adults live in oceanic waters, bays, and estuaries when not spawning. Feeding on algae and small invertebrates while young, green sturgeons migrate downstream before they are two years old. Juveniles remain in the estuaries for a short time and migrate to the ocean as they grow larger. The green sturgeon can become highly migratory later in life. They have been documented as traveling over 600 miles between freshwater and estuary environments.
Green Sturgeons are bottom feeders. They spend most of their lives cruising river bottom in and out of deep holes in search of food. Natural food will drift down river dropping into and resting on the bottom. Adult green sturgeon feed on benthic invertebrates and small fish.
Spawning
Green sturgeons are an anadromous fish, spending most of their life in near shore oceanic salt waters, bays, and estuaries. Early life stages reside in fresh water, with adults returning to freshwater to spawn when they are more than 15 years of age and more than 4 feet (1.3 m) in size. They prefer to spawn in lower reaches of large rivers with swift currents and large cobble substrates, but range from clean sand to bedrock substrates; no nest is built, adults broadcast spawn into the water column. Green sturgeons can spawn in deep pools or holes in large, turbulent, freshwater river main streams. Spawning is occurring every 4 to 11 years. Adults typically migrate into fresh water beginning in late February; spawning occurs during the spring and summer months, from March-July, with peak activity from April-June. Females produce 60,000-140,000 eggs.
The fertilized eggs sink and attach to the bottom to hatch. Water flow is one of the key determinants of larval survival. Cold, clean water is important for proper embryonic development. Juvenile green sturgeons spend 1-4 years in fresh and estuarine waters before dispersal to saltwater. They disperse widely in the ocean after their out-migration from freshwater to estuaries and marine environments.
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The green sturgeon is commercially caught along with the white sturgeon in the Columbia River, Grays Harbor, and Willapa Bay. The green sturgeon is not as valuable as the white sturgeon because its flesh is considered inferior to that of the white sturgeon.
Sturgeon can be found and can be caught all year though best fishing is between March & November. At some point in the life cycle, larger sturgeon migrate to the ocean and will travel to other river systems and ocean estuaries.
There are two major feeding periods when sturgeon fishing is at its best; April- June and September- November. During the winter months most fish being caught are smaller, 2 to 4 feet is average. Once spring sets in, in April, larger fish begin to migrate from freshwater to the ocean. Size average will increase to 3-5 ft, and chances of catching good size fish are very good. The second major feeding period is when the sockeye salmon enter the Fraser, the sturgeon will strategically place themselves below popular fishing areas and will feed heavily on salmon parts discarded by anglers. They will also feed on salmon eggs and whole live and dead fish. This is the last major feeding period before winter sets in and food becomes scarce so feeding periods are long and fish are very aggressive towards good baits.
There are two ways to fish for sturgeon; from a boat or from shore. For boat fishing better to use 6-9 ft one piece rods with a level wind reels and 60- 100 LB test line (250-300 yards). Shore rods are 11- 13ft two piece with large spin casting reels. The longer shore rods the better castability, these longer casting rods can launch 12-20 ounces of weight far from the beach in the deeper places. When fishing Green sturgeons you must be patient, you have to wait until the bite to be a steady pulsating pull and don’t set the hook too early. Once you've hooked a fish you will have plenty of backbone to fight and land a large fish.
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