Digifish

  The ocean's resources were long considered inexhaustible.  For a long time, it was seen as unthinkable that humans could affect fish stocks.  During the industrialization of the 19th and 20th centuries, ever larger areas became available for fishing, while the efficiency and scale gradually increased.  Together with eutrophication, habitat destruction, a warmer climate and possibly environmental toxins, this affects the fish negatively today.       During the 19th and 20th centuries, fishing was  largely free, which enabled an unlimited take of fish and shellfish. During the 20th century, it became difficult to ignore the negative effects of fishing on stocks. Restrictions in fishing were gradually introduced through so-called quotas. However, in negotiations between countries about quotas, little consideration was often given to biological knowledge , which resulted in the quotas being set far above what the fish stocks could withstand in the ...

 Stocks of cod and many other fish species are at historically low levels in the Kattegatt and Öresund. The introduction of the fishing-free area in the southern Kattegat initially showed positive signs for cod and crayfish , but cod has since declined again. Other positive signs are that the stock of plaice in the Kattegat is increasing. Coastal stocks are dominated by flounder and there are a lot of shore crabs, while the predatory fish are few and small. Cod stocks in the Kattegatt increased from very low levels in the late 2000s partly as a result of the no-fishing area and technical regulations. In recent years, however, the stock has shown a declining trend again. It is now at the lowest level ever measured. Gray whiting in the Kattegatt, which belongs to the same stock as that in the Skagerrak , has increased since the bottom in the early 1990s but only to about half the levels in the mid-1970s. The stock of plaice in the Kattegatt and Öresund has increased steadily since 20...

  Sweden's has one of Europe's longest coastlines, with very varied habitats for fish.  A decisive factor for the distribution of different fish species along the coast and in the sea is the salinity.  It varies from close to oceanic salinity in the Skagerrak to basically fresh water at the top of the Gulf of Bothnia .  Along the gradient there are many different species of fish, from cod and sole on the West Coast to perch and roach in the Gulf of Bothnia. The condition of the fish along Sweden's coast and in the sea varies considerably.  Due to over-fishing, many of the stocks of codfish, flatfish and cartilaginous fish in the sea are at historically low levels, with few exceptions such as plaice in the Skagerrak and Kattegatt.  For example, cod in the Skagerrak and Kattegatt are today at very low levels, and in the Baltic Sea proper the cod stock is dominated by small individuals in poor condition.  The pelagic stocks of herring and sprat show diffe...

 Valued but threatened natural resource. Fish are a valued natural resource found in most aquatic environments. Fishing is carried out as recreation or as a profession and it is regulated in several different laws, ordinances and regulations. The amount of fish, species composition, age and size varies naturally between different water environments, but also depending on how the fishing is conducted and on what otherwise affects the quality of the current water environment.  Fish are central to the aquatic food web. This means that they can be directly affected by changes in the environment such as increased water temperature or environmental toxins, but also by changes that occur at other trophic levels such as changed availability of food or the number of predators. Fishing has a major impact on the size and condition of fish stocks. The monitoring of fish is carried out both nationally and regionally in seas, lakes and waterways. The data that is collected is the basis fo...

  The neon tetra  is a small freshwater fish native to South America.Due to its vibrant colors and ease of care, it is one of the most popular fish  among fish breeders.Its peaceful temperament and simple dietary needs make it an ideal fish for beginners. Common name  -             Neon Fish, Neon Tetra Scientific name -            Paracheirodon innesi, Hyphessobrycon innesi Aquarium capacity  -    37 liters, 75 liters for a school of 15 specimens Temperature  -                Between 21° and 28° C pH -                                 Between 4 and 7.5 GH -                              Less than 8 Temper-                     ...

Oscar Fish Care Guide The Oscar fish, scientifically known as Astronotus Ocellatus or commonly known as River Dog or Dog Fish, is one of the largest South American cichlids reaching approximately 12 inches in length and is a fascinating fish to keep as a pet.  Oscars are very docile fish in relation to their owner, but you have to be very careful around your tank mates. They are not very difficult to care for, so many aquarists who can afford a large tank and love cichlids start by keeping Oscars. tank requirements First of all, being so large, Oscars will need a very large tank, 125 gallons minimum for one fish or a pair.  Like all fish, the water must be very clean, so you must use a very powerful filter, since fish that big produce a lot of waste. Oscars are tropical fish, which means they like their water to be between 72 and 77 degrees Fahrenheit and do well in slightly acidic water with a pH between 6.5 and 7.2. They prefer weak water movement, but you should use at lea...

  Celestial Pearl Danios have made quite an impact in the fish-keeping community since their discovery. They’ve since become a crowd favorite because of their many attractive attributes.  Their fun and active nature as well their splendid appearance, are more than what any tank owner could ask for. And since they have minimal needs and are easy to take care of, they’ve become extremely popular amping aquarists . So if you’re ready to learn more about this interesting fish, keep on reading. We’ll tell you all you need to know about it, from its origin to how to provide it with all its essential requirements so that you can enjoy its presence in your tank for the longest time possible. Overview: Origins & Appearance The Celestial Pearl Danio has been greatly loved and sought after since its discovery in 2006 due to its small size, ease of care, and beautiful appearance. It has a small and slender body that’s dotted with off-white spots resembling tiny pearls and averaging ab...