#bighead carp

[anderstiaagain]

[gilmafish]

gilmafish

Gilma FishThe world is in search of organic, healthy, and low-cholesterol protein sources.Protein and meat are essential parts of people’s diets. But what does nature offer that is both healthy and low-fat while being nutritious?Fish! With its white meat, low cholesterol, delicious taste, and abundance of nutrients like iron and calcium, fish is an ideal choice. It provides essential dietary needs with minimal fat and accounts for a significant portion of the world’s total meat production—an industry valued at approximately $340 billion by 2022.Asia, blessed with rich natural resources, is the largest supplier of edible fish globally. Within this region, Iran stands out as the third-largest producer of warm-water fish and the leading global producer of rainbow trout and beluga sturgeon caviar. This highlights Iran’s remarkable potential in the seafood industry.In northern Iran lies Gilan, a lush green province renowned for its natural treasures like the Caspian Sea and the Hyrcanian forests. Gilan is one of the country’s top producers of warm-water and sturgeon fish. The Caspian Sea, the largest lake in the world, is home to invaluable sturgeon reserves, while Bandar Anzali, a key port on its shores, serves as a reliable gateway for exporting this vital product worldwide.Fish is a “green food” that promotes a healthier lifestyle. Gilan, as the heart of this chain, plays a crucial role in bringing this nutritious treasure to people worldwide.Gilma = Green Food = Green Life!

Gilmafish.com

[insaneiceshard]

Hehehe weird fish

[bethanythebogwitch]

Wet Beast Wednesday: invasive carp

I've mentioned on a few posts that in a previous job I helped remove invasive carp from the Mississippi river and drainage. For this Wet Beast Wednesday I'll discuss the three species that I personally helped remove: the silver carp, bighead carp, and grass carp. The common carp (Cyprinus carpio) and block carp (Mylopharyngodon piceus) are also invasive in North America, but I didn't remove either of those: the black carp because they haven't made it as far north as the area I worked and the common carp because the state governments where we worked considered them commercially important species. All the invasive species collectively described in America as invasive carp or Asian carp are large fish from the family Cyprinidae who are native to east Asia. They have been introduced to areas far beyond their native range for use in aquaculture and for food. Carp aquaculture in China goes back over a thousand years and the three species plus the black carp are known as the "four domesticated fish" for their importance in food and traditional medicine. The carp were introduced to America to clean aquacultural and decorative ponds and quickly escaped into the river system. They are now highly invasive throughout the Mississippi river basin and have also spread into other river systems, including the Illinois and Ohio rivers. All the introduced carp species are considered highly invasive due to outcompeting native species, lacing predators as adults, and their hardiness allowing them to thrive in harsh conditions.

This picture isn't informative at all, I just thought it was funny (image: a close-up of the head of a silver carp, showing its eye and large, open mouth)

Silver carp (Hypophthalmichthys molitrix) made up the majority of the carp I caught. In their native range (from Vietnam to eastern Siberia), silver carp are actually considered threatened due to overfishing and habitat loss. Outside of their native range, they have become highly invasive in multiple parts of the world. Silver carp notable for their large head and silvery scales, which become brighter in healthier fish. They reach an average of 60-100 cm (24-39 in) and 9 kg (20 lbs), but can reach a maximum size of 140 cm (55 in/4.6 ft) and 50 kg (110 lbs). They are filter-feeders, primarily dining on phytoplankton but also eating zooplankton and organic particles. To catch food, they use specialized gill rakers that have fused together into a spongy surface and is coated with mucus that traps particles. As with all Cyprinids, silver carp lack stomachs, instead having their intestines attaching directly to the esophagus. Lacking a stomach makes the fish less efficient in their digestion and they feed near constantly. Silver carp were introduced to America to clean blue-green algae from ponds, aquaculture facilities, and water treatment plants. They consume so much plankton that they can outcompete local species, such as freshwater mussels, paddlefish, buffalo, and shad, as well as larval fish of most species.

(image: a silver carp being held by a person (offscreen). The fish is seen from the side. It is a large fish with a silver color. Its head is relatively large and has no scales. The eye is unusually low on the head)

Silver carp migrate upriver to broadcast spawn, with their eggs and larvae being washed downstream where they grow in shallow waters like floodplains. Silver carp trapped in places without flowing water will not spawn, instead reabsorbing their gametes. Males have rough skin on the front of their pectoral fins, which they will scrape against the bellies of female to induce them to release their eggs. Females that have spawned at least once often have scars on their bellies that can be used to identify that they have reproduced. Silver carp reach sexual maturity between ages 4 to 6 and can live up to 20 years.

I believe I can fly! (image: a silver carp in profile midway through a jump out of the water)

Silver carp are famous for leaping out of the water when startled. They can reach up to 3 m (10 ft) out of the water, though larger individuals are less likely to jump. The sound of boat engines can easily spook the carp into jumping and there are many videos out there of boats moving through rivers surrounded with dozens to hundreds of jumping carp. The jumping behavior combined with the sheer size of the fish makes them a hazard to boaters, as colliding with a carp can damage boats and cause serious injury. Interestingly, carp in their native range are much less likely to jump than those in North America. The reason for this in unknown though it could be because carp in America live in much higher population densities than those at home. It is also possible that the carp first introduced to America happened to have a trait making them more likely to jump and this trait has been passed down to most modern carp.

(image: a small boat with three people on it. In the foreground, dozens of silver carp are jumping out of the water, causing the water to become frothy)

(gif description: a man is sitting on a running boat. A silver carp jumps in from the right side of the frame and hits him in the face, knocking his baseball cap off)

The bighead carp (Hypophthalmichthys nobilis) is closely related to the silver carp, enough so that they can hybridize to make fertile offspring. Bighead carp have darker scales and larger heads, but what really makes them stand out is their size. They reach an average of 60-100 cm (2-3 ft) and 18 kg (40 lbs) but can reach a maximum of 160 cm (5.2 ft) and 50 kg (110 lbs). They fill a similar ecological nice to silver carp, both species being filter feeders with specialized gill rakers used to filter out plankton. Bighead carp prefer zooplankton in contrast to silver carp targeting phytoplankton. They are highly valuable in aquaculture as they grow quickly, allowing for a lot of meat to be developed relatively quickly. Like silver carp, they swim up river to spawn and reach sexual maturity between 2 and 3 years. They can live up to 16 years. Bighead carp will also jump, but are less likely to do so, especially once they mature, and are therefore less notorious than silver carp.

(image: two bighead carp underwater, one closer and to the bottom right and one farther away at the top left. They are very similar in appearance to the silver carp, but have larger heads and darker scales, making them look brown. The closer fish has its mouth open)

Grass carp (Ctenopharyngodon idella) were the species I caught the least. They can be distinguished from the other two with their long, skinny, and round bodies, larger sales, and green coloration. Unlike the other two, grass carp are herbivores with teeth that feed on aquatic vegetation, though they also consume detritus and invertebrates in smaller amounts. Grass carp can eat up to a few times their weight in food a day. Grass carp can destroy whole patches of aquatic vegetation, which removes food sources for other animal, removes refuges for fish and other animals to hide, and can drastically alter the trophic web of local areas. They live in still ponds or rivers with slow currents, but move into fast-flowing rivers and swim upstream to spawn. They can reach between 60 and 100 cm (23.5 - 39.5 in) on average, but can get up to 2 m (6.6 ft) and 45 kg (100 lbs). Grass carp were first introduced to America to act as weed control in ponds before escaping into the wild. It is still possible to import grass carp for weed control, which is astonishing to me since thats how we got into this mess in the first place. Grass carp are highly valuable in fisheries and are used as a food source throughout their native range. They are the most farmed fish by biomass, with over 5 million tonnes of grass carp produced in fisheries every year. The second most farmed fish is the silver carp.

(image: a grass carp underwater. Its body is slender and torpedo-shaped, with large, distinct, green scales. Its head is scaleless and its eye is level with its mouth. A second fish is peeking into frame at the bottom right)

One of the problems with controlling carp in America is the lack of a market for them. They are not commonly eaten in America despite being a major food source in China and other parts of east Asia. This is in part because of the association the phrase "Asian carp" has with the common carp, which was introduced to North America before the other species and is generally considered to have poor-quality meat. Because there is no market for invasive carp, fishermen do not bother removing them from the rivers and many do not bother taking the time to kill the ones they do catch. A few conservation efforts are attempting to make a market for the carp so that fishermen will take them. When I was at my last job, we gave the carp we caught to someone who used them for fertilizer and bait. A current effort by the Illinois Department of Natural Resources and the U.S. Environmental Protection Agency is to rebrand the carp as Copi (from copious) in an attempt to get around the stigma that carp tastes bad and get Americans to start eating them. Copi is currently being sold in or distributed to multiple states and DC. The project has already exceeded the expected amount of fish removed in weight for the first year. Other rebrand attempts include Silverfin, the perfect catche, and (my personal favorite) Kentucky tuna. This rebranding is part of a major push to try to keep the carp out of the Great Lakes, though grass carp have already gotten into Lake Erie. If you can't beat them, eat them.

Image: the copi logo. It is the word "copi" written in a dark blue, blocky, minimalistic font. The letter O is replaced by a simplistic drawing of a light blue fish, whose tail forms the curve in the letter C)

[thecanadianweeb]

bighead carp

[sciencenewsforstudents]

A mussel poop diet could fuel invasive carp’s spread across Lake Michigan

Asian carp, just a human-made waterway away from reaching Lake Michigan, could live in much more of the lake than previously thought.

If invasive carp reach Lake Michigan, a buffet of mussel poop and other junk food could help the fish survive and spread.

Once thought to be a food desert for these fish, the lake may provide enough nutrition for two Asian carp species, bighead (Hypophthalmichthys nobilis) and silver carp  (H. molitrix), thanks to their not-so-picky eating habits, researchers report August 12 in Freshwater Biology. That’s bad news because the carp, which have spread to the Illinois River since their introduction to the United States in the 1970s, are just a human-made waterway away from getting into Lake Michigan.

“We should be doing everything we can to keep bighead and silver carps out of the Great Lakes,” says Sandra Cooke, a freshwater ecologist at High Point University in North Carolina who was not involved with the work. If carp gain a finhold, their populations could eventually take off, with difficult-to-predict consequences for the lake’s ecosystem. It’s a familiar trajectory for invasive species (SN: 3/18/17, p. 30). “Time and again, what we actually observe is worse than what we predicted in the first place,” she says.

Earlier studies, including by Cooke, suggested that these fish could survive in some nearshore spots, based on levels of carp’s preferred food, microscopic algae known as phytoplankton, in the top meter of water. But when better options aren’t available, carp will eat detritus, including fish poop or decomposing dead organisms, says Peter Alsip, a freshwater ecologist at the Cooperative Institute for Great Lakes Research at the University of Michigan in Ann Arbor. In fact, he says, the scrappy fish can subsist entirely on the low-quality food that comes from mussels’ fecal pellets and regurgitated particles.

In the new study, Alsip and his colleagues used water temperature, depth, available nutrition, the fishes’ appetite — including for junk food — and their energy needs to simulate where in the lake the carp could reside. Invasive zebra and quagga mussels cover much of the lake floor, presumably creating a “huge portion” of the detritus in the lake. So carp may be able to survive in much more of the lake than previously thought, Alsip says.

JUNK FOOD Fueled by bits of matter from mussel poop, bighead carp (Hypophthalmichthys nobilis) could find enough to eat offshore in Lake Michigan, creating a highway of sorts to nutrition hot spots that would be better for spawning. CREDIT: ELIZABETH SELLERS/FLICKR (CC BY-NC-SA 2.0)

For instance, if bighead carp consume mussel poop and zooplankton in addition to phytoplankton, the surface area corresponding to where the fish could live quadruples on average during the warmest months of the year. Simulations show that the habitable area grows from 11,144 square kilometers to 43,308 square kilometers — about three-quarters of the entire lake. The habitable area for silver carp could double from 1,436 square kilometers to 2,758 square kilometers, the analysis found.

Rather than taking up residence in the middle of the lake, the carp may be more likely to treat the widespread detritus as sustenance to cross the massive lake to areas with better food. It would be as if “these fish want to drive on the interstate and they’re looking for a Cracker Barrel or some other food,” says Jim Garvey, an aquatic ecologist at Southern Illinois University in Carbondale, who was not involved with the study.

Bighead and silver carp were brought to the United States in the 1970s to control the growth of algae, which flourished on pollution dumped into streams. But during floods, the fish escaped their holding ponds. By the 1980s, it was clear the carp were spawning in the wild. The invasive fish are now found throughout the Mississippi River Basin, including on the Great Lakes’ doorstep. In the Illinois River, carp now account for nearly two-thirds of the fish biomass, research by Garvey and others has found.

Predicting when or how an invasive species will establish itself is difficult, Garvey says. “There are always surprises.” Tackling a complex lake ecosystem with such detail moves in the right direction by looking at where the fish might thrive, he says.  

[aticketplz]

ちっちゃくてかわいいのがいました

絶対口あけちゃうマン

@東京タワー水族館

[aticketplz]

デッサンが下手でかわいい

@アクア・トトぎふ