Memaparkan catatan dengan label fish. Papar semua catatan
Memaparkan catatan dengan label fish. Papar semua catatan

Khamis, 15 Mac 2018

More About Salmon


School of salmons marching to their breeding ground. Photo by: PatClayton

Salmon is one of the fish largely farmed these days. The farming technologies help more people from all around the world to enjoy eating salmon at the same time avoiding wild salmon to recover from overfishing, loss of habitats due to dam constructions deforestation and development. No one knew the exact numbers of the ideal salmon in the wild, but avoiding further damage to the wild population in important before it’s too late.

There are more interesting things about salmon that we need to know. As the salmon that grows for commercial purposes only few types that suitable for the farming industries. While there are many other salmons included in this family and some of them not even migrate to the sea as other salmon do. So what happen to them? Are all of them threaten as the common salmon (Atlantic salmon: Salmo salar and Pacific salmon: genus Oncorhynchus)?

Salmon's steak. Photo by: J.Kenji L√≥pez-Alt 

Chinook salmon, the largest salmon today. Drawing of Ocean Phase Chinook (king) salmon (Oncorhynchus tshawytscha). Image by: eopugetsound.org

Salmon is the group of fish in the family Salmonidae that also includes trout, char, grayling and whitefish. But the salmon that we are going to talk about are mostly the two popular group of North Atlantic (genus Salmo) and Pacific Ocean (genus Oncorhynchus) and few more species in the same family.

The main group of salmons show in the table below with their genus, names, scientific names, maximum length, common length, maximum weight, and maximum age. These are also the salmons that use as farming salmon for commercial purposes. From their maximum age, we will know their life cycles and how long it would take for the salmon to restore their population.

Genus
Common name
Scientific name
Maximum
length
Common
length
Maximum
weight
Maximum
age
Salmo
(Atlantic salmon)
Atlantic salmon
Salmo salar Linnaeus, 1758
150 cm
120 cm
46.8 kg
13 years
Oncorhynchus
(Pacific salmon)
Chinook salmon
Oncorhynchus tshawytscha (Walbaum, 1792)
150 cm
70 cm
61.4 kg
9 years
Chum salmon
Oncorhynchus keta(Walbaum, 1792)
100 cm
58 cm
15.9 kg
7 years
Coho salmon
Oncorhynchus kisutch(Walbaum, 1792)
108 cm
71 cm
15.2 kg
5 years
Masu salmon
Oncorhynchus masou(Brevoort, 1856)
79 cm
cm
10.0 kg
3 years
Pink salmon
Oncorhynchus gorbuscha (Walbaum, 1792)
76 cm
50 cm
6.8 kg
3 years
Sockeye salmon
Oncorhynchus nerka(Walbaum, 1792)
84 cm
58 cm
7.7 kg
8 years

Other than the main species of salmons there are few more salmon that we should know;

  • Black Sea salmon (Salmo labrax) - small species of salmon with 51 cm (20 in) in length on average and can reach up to 76 cm (30 in). This species inhabits the northern Black Sea coast and inflowing river. Same as other salmon they are also anadromous, lacustrine and resident river populations. Spawn in October - January. Parrs live in rivers for 2 - 4 years, then smoltify and migrate to the sea or mature in the freshwater. They can spend for another 2 - 4 years before return to the spawning areas. Their conservation status also showing least concern.
  • Danube salmon (Hucho hucho) - also known as huchen, is a large freshwater fish. They never go to the sea as any other salmon. Huchen is endemic to the Danube basin in Europe. They also reported to be found in the Dniestr basin in the historic time and in big dam reservoirs on the mountain such as Lake Czorsztyn in Poland. Huchen is a big fish with size up to 1.5 m (4ft 11 in) and weight up to 50 kg 110 lb). The modern record for largest huchen is 34.8 kg (77 lb), caught in February 1985 in Spittal an der Drau in Austria, while older records reported weights in excess of 60 kg (130 lb). Unfortunately the conservation status for huchen already reach the level of “threatened.
  • Sabertooth salmon (Oncorhynchus rastrosus) - is an extinct species of salmon that can grow to very large sizes. They lived along the Pacific coast of North America in the late of Miocene Period, near California. The adults grew up to 2.7 m (9 ft) in length and also an anadromous like the modern salmon. They have a pair of small fangs protruding from the tip of the snout that also gave them their name. Even though so big they believe to be planktonic feeder. More about sabertooth salmon can be found here.

Black Sea salmon. Photo by: Otel,Vasile  
Danube salmon. Photo by: Hartl,Andreas
The display of saber-tooth salmon at Museum of Natural and Cultural History in Eugene. Photo by: RACHAELMCDONALD

Yes there are many other fish in the same family of Salmonidae. If you want to know more details about the sub-species in this family the best place to look for them is through fishbase. While salmon farming get better in producing good quality of salmon every year and the wild salmon population getting increases. The sub-species of salmon too should be taken care off too. With more knowledge shares among publics the awareness of conservation will be taken more seriously by each individual.



Free Download





Selasa, 13 Mac 2018

How Nutrient From The Sea Ended Up In The Forest?

Chum salmon swimming their way back to their breeding place. Photo by: Thomas Kline, Salmonography.


It’s hard to believe that trees deep in the forest get their nutrients far-far away from the sea. That what the wonder on nature when they work together accordingly. One of examples that we can see is the returning of salmon during the breeding season.

Salmon is one of few species of animals that start their life in the freshwater and spend their growing time in the sea then return back only to lay their eggs. As they return their journey back to the deep forest that might take few thousand kilometres as example of chum salmon (Oncorhynchus keta) that travel the longest journey far up to Yukon River and deep into the Amur River basin where the journey will take more than 3,200 km (2,000 mi).

Alaskan brown bear with chum salmon. Photo by: Alan Vernon

Salmon alevin. Photo by: OpenCage

Within their journey they will become meals for numbers of other animal species such as eagle, otter, water birds, and bear that waiting for their returning from the sea. Then for the surviving salmon will continue their journey to their breeding place far into the forest. Their journey up the river requires them to have strong muscles, with it they are capable to leaps more than 2 meters height.

Travelling far from the sea will make salmon lost lots of energy all of them will die after spawning their eggs. Their carcases might be taken by other animals out of the water and left the remaining alone. Then the remaining will become home to blow fly’s larvae that will eat on the remaining flesh.

Once they are ready, the maggots will buried themselves in the soil until they emerge as adult flies. These flies again will do another important thing for plants and trees in the surrounding areas; pollinating the flowers to make sure they can produce seeds for their next generation.

Dying salmon after the breeding season. Photo by: Ned Rozell

Death salmon releasing nutrients from the sea. Photo by: fishbio.com

We might think that salmon just one species of animal and maybe important to those few animals that eat them. With closer observation we can see how all the ecosystem intertwine together with every single piece of them nourishing one another.

Even though each female salmon can carry from 2,500 to 7,500 eggs depending on size and species, only some of them will hatched. From that numbers less than 2 percent will return to the same location to spawn again in the next 6 to 7 years.







Free Download




Rabu, 7 Mac 2018

More Interesting Things About Flying Fish

Flying fish leaping out of the water in group - Photo by: caribbeannewsservice.com


Flying fish is the only fish that can fly or actually gliding in the air in order to avoid their predators. Compared to its body size the distance they can achieve from the glide is considered very far. Even though this behaviour help them to run away from the predators, but their predators too have different techniques to catch this super leapers.

Flying fish are family of fish known as Exocoetidae, in the order of Beloniformes class Actinopterygii, with 64 species from 9 genera. They can be found in all of the oceans, mostly in tropical and warm subtropical waters. That’s the other reasons why flying fish is quite popular as part of people’s culture all over the world, from Japan, Vietnam, China, Indonesia, India, South America such as Barbados and Trinidad and Tobago. Besides of that, flying fish still can be found in many other areas (even when they are not become part of people consumptions for that areas).

Flying fish has a bigger fins than usual fish. - Photo by: hootersbutwithcats

Flying fish from the side. - Photo by: Thinkstock

Flying fish can achieve great distance when they gliding above the sea. The distance can get farther with the right condition of wave and wind. They can reach up to 4 feet heights and gliding distances up to 655 feet. Sometimes they will continue the jump soon after touching the water to reach longer distances up to 1,312 feet. They also can soar high enough and sometimes get stranded on the decks of ships.

Flying fish become important food source for other bigger species of fish in the sea and when they leap out the water, birds too will take advantage to make them as their food. With their size can reach up to 18 in (45 cm), flying fish is consider moderate in size. Flying fish had been using in many dishes all around the world. One of the popular dishes is the flying fish sashimi from Japan.

Fried flying fish. - Photo by: Josh Berglund
Sashimi - Tobiuo (Flying Fish) - Photo by: travel.gaijinpot.com 



Fisherman caught them with different ways such as using gillnetting in Japan, Vietnam and China, while using dipnetting in Indonesia and India. There’s also a technique using lights to catch this fish as they are attracted to the lights (especially during the dark moon).

Catch in the mid air by bird. - Photo by: aquarium.ucsd.edu

Chase under the water. - Photo by: YouTube

Even though flying fish is not considered as threaten species, their hunting should be controlled in order to avoid overfishing. Flying fish is important to human especially in some cultures, but they are more important to the nature itself.





Free Download




Sabtu, 24 Februari 2018

Fish Farming Of The Future

Atlantic salmon is threaten in the wild. Photo by: imgur.com

Fish is one of the important protein sources but badly affected by many issues from pollution, over-fishing, unsafe even for farmed fish and caused threats to environment. While stopping fish farming will never stop the other threats for the wild fish and we still need fish as part of our foods. Luckily some of us never stop to find better ways to raise farm fish with better condition.

Farming fish is not an easy job especially salmon that requires both between salt water and fresh water. This fish is bigger in size with carnivorous appetite. Farming salmon in the net-pens over the rivers and lakes been practiced for so long and proven caused many problems for the fish itself and for the environment. Using other fishes as their food also another reason salmon farming will not solve the over-fishing problem.

Atlantic salmon swimming in the wild. Photo by: imgur.com

Cleaner water and easier to control (land farming). Photo by: seacoreseafood.com

With more people come forward and pressure from the consumers, fish farmers find another solution – to raise salmon in land away from natural water supply. With enclosed environment all factors are control properly from the quality of water, oxygen content in the water, salinity to food supplies. These lead to easier manage conditions; even though the cost of building the facilities far higher than traditional net-pens farming.

One of the pioneering company in this technology is KUTERRA that raising Atlantic salmon (Salmo salaron their farm at Northern Vancouver Island, Canada.

The land farming allows farmers to control many other threats to their fish such as predators, pollution from the water, diseases and water from the farm also never goes into the river/sea. With high circulation of water, low fish feed, controlled temperature and oxygen, the growth of fish are much faster with no diseases. In case of diseases they can change all the water and sanitized all the facilities again.

Damage net in net-pens farming: Photo by: KUOWPHOTO/MEGAN FARMER

More and more land farm will be build. Photo by: undercurrentnews.com

Even though the cost to build land farm are far higher, but it can produce higher yield with good quality of fish. Not to mention they never caused any harm to nature (other than the land they need to use to build the farm). This technology is still in its early stage and there are more improvement in the process and management that will bring better result.

In fact salmon farming is not the only technology that got a facelift in recent years. All other fishes with high demands and threaten in the wild such as tuna, grouper, cobia, puffer fish, and few other shellfish/crustaceans also had been upgraded. This upgrade not only to produce more production but also to make sure that the produce will be safe for human consumption with less impact to the environment.



Salmon produced by KUTERRA. Photo by: kuterra.com

Deep sea farming also will be part of future fish farming. Photo by: innovasea.com 
With more people work together to improve the quality of fish farming industries, it will benefits both the consumers and the farmers. While at the same time we hope that will allow the restoring amount of the fish in the wild from over fishing – but still threatens by pollutions of many kinds.







Free Download




Arkib Blog