All posts by apsvoboda

China’s lack of Fish Management

China loves fish. However, due to lack of management they have decimated many of their wild populations. Governmental policies in  China have  largely neglected environmental issues. Many  dams have been built, waters polluted and/or  fished out. As a result  fisherman now have  to focus there efforts in international waters.

China consumes four times as much fish as America does. Therefore they have had to innovate to successfully  acquire enough fish for their growing population. This innovation has largely been in the way of fish farming. As many as 14 million people are now employed in aquaculture. For the Chinese, fish is an important staple but without a new push to protect their remaining wild species, even fish farming may not be able to keep up with demand.

Scientists Study Entire Ecosystem to Manage Fish Populations

 

Alaska harvests more seafood annually than all other 49 states combined. Most of these fish begin life as tiny larva at the mercy of their environment. When everything goes well, currents carry them to fertile waters where they can grow and be recruited to the harvestable population. When conditions aren’t favorable most if nit all larva carried into a certain area will die.

To begin to better understand these conditions, more than 50 scientists are teaming up to study the Gulf of Alaska. The project, named, The Integrated Ecosystem Research Project, ”  brings together physical oceanographers, fish biologists, and other scientists to decipher how physical and biological forces in the ocean combine to determine fish recruitment.”

The goal of the project is to help make sustainable decisions about the future of Alaska’s fisheries as the pressures of climate change and other man-made factors play increasing roles in fisheries throughout the world.

https://www.nmfs.noaa.gov/stories/2014/04/4_09_14alaska_ecosystem_research.html

Crude oil Effects Large Marine Fish Development

(Top:  healthy tuna  larva. Bottom:  larva exposed to crude oil)

According to a newly published study conducted by NOAA and other scientists, crude oil, is responsible for, “development abnormalities” in yellowfin and bluefin tuna. The research  began in the Gulf of Mexico, the site of the Deepwater Horizon in 2010,  the United States’ largest oil spill.

Reaching their findings was  extremely challenging, as tuna are notoriously hard to raise in captivity and usually do not survive being captured. The team had to use the only land based Bluefin tuna hatchery in the world, located in Australia to conduct their experiments. The study found that crude oil causes heart conditions in tuna, and several other species, which can lead to heart failure. Other conditions include physiological  deformities and death.

The study also found that the levels of the toxins found in crude oil that result in damage can be low as 15 parts per billion. A very alarming discovery considering that an oil spill the size of the Deepwater Horizon spill released upwards of 4.9 million barrels of oil into prime tuna spawning habitat.

https://www.sciencedaily.com/releases/2014/03/140324154017.htm

Farmed Salmon Proven to be a Reproductive Threat

Scientists have just released a study proving that domesticated salmon are just a fertile as wild salmon. These findings raise even more concerns about the risks of salmon farming in relation to preserving wild gene pools.

It is well documented that many farmed salmon  escape into the wild each year. These fish, acting on instinct to spawn will often times migrate up rivers and do just that. The major problem with this is  that these farmed salmon introduce new genes into wild populations that are often times not beneficial. Farmed salmon are notoriously lacking in their ability to sense predators and  are often times very aggressive. These traits bode well for domesticated salmon in captivity but can be extremely detrimental to wild populations.

To reach their conclusions on farmed salmon fertility, researchers used in vitro fertilization, as well as, “tests of sperm competitiveness and egg compatibility.” Their results proved that farmed salmon pose a threat to wild gene pools.

https://www.sciencedaily.com/releases/2014/03/140310090927.htm

Decimated US Fisheries Bouce Back

A new study states that nearly 2/3 of closely monitored fish species in the US have overcome overfishing due to effective management strategies. The study points to management over the last 10 to 15 years as the key to success. The study conducted by NOAA found that 28 of  44 listed species had  adequately  recovered to be considered sustainable. The study also found that 16 species have made very little progress. Scientists feel that this is due to continued overfishing in certain areas, as well as natural variation among reproductive rates in certain species.

Of the species that still struggle to recover, the Atlantic cod has proven to be one of the most difficult to revive. Vast over fishing that decimated the population many decades ago has decreased, but the species has struggled to rebound, forcing even more cuts to the already limited quota. Though the situation seems dire for the fisherman, continued strict management has the goal of restoring this fishery to its former glory.

https://news.nationalgeographic.com/news/2013/03/130326-fish-stocks-rebound-fisheries-management/#.UxkZtSyYbIU

 

Arctic Grayling

Photo of a Arctic Grayling

Hello, my name is Arctic Grayling. My scientific name is Thymallus arcticus. Some people also know me as American grayling, bluefish, arctic sailfish, and  arctic trout.

I am a truly beautiful fish. My most well know trait is  my  extremely large dorsal fin in proportion to my body size.  I can range from black, to blue, to gold to silver. I have black spots on my sides and my fins are often fringed with orange, red, or pink. The most recognizable difference between the males and females of my species is body and dorsal fin sizes. Us males tend to grow larger and commonly sport larger dorsal fins.

I spawn in the spring. I typically choose small, clear tributaries of rivers and lakes with gravel or rocky bottoms. After females release their eggs over a suitable section of stream, males fertilize them. Both males and females then return to the rivers or lakes from which they came. My species can live as long as 32 years so I have the opportunity to spawn many times.

I am a tertiary consumer in my environment. I feed nonstop in the summer months as winter is long, cold, and food is relatively scarce. I like to eat a insect rich diet, as well  as, salmon smolt and  salmon eggs. Larger members of my species have even consumed voles!

I prefer to live in clear, cold water. I can be found in lakes, rivers, and streams. I tend to stick to shallower, rocky locations. I will move throughout the year to find the best food and suitable water temperatures. I am very sensitive to water pollution but can survive on little oxygen. I am found throughout Alaska and Canada but was once found in most of the northern regions of the lower 48. But due to overfishing, pollution and habitat loss, I am now  confined to isolated populations in Montana and Michigan. I have also been introduced to California and Arizona.

As a youngster, I  had quite a few predators, such as trout, larger grayling, and birds. As I grow older I tend to enjoy a  rather high status on the food chain. But I am still subject to being snatched by eagles and caught by humans.

As I mentioned before I can live to be 32 years old! But I try to live within my means. I the summers I am very active, I feed and bulk up for winter during which I usually spend most of my time burning as little energy as possible. In the spring I migrate to spawn and start the year over again.

https://www.adfg.alaska.gov/index.cfm?adfg=arcticgrayling.main

https://www.gotmyfishon.com/washington/fish/arctic-grayling

https://www.stoneflysociety.org/fishinfo/arcticgrayling.htm

https://fieldguide.mt.gov/detail_AFCHA07010.aspx

 

 

 

Bee’s Surpirsing Resourcefullness

Plastics finding their ways into ecosystems is a growing global problem. Increasing human usage of plastic products and irresponsible disposal practices puts many animals in harm’s way, as they are not biodegradable and consumption of plastic objects is often times fatal. However, a new study has found that urban bees have found a way to utilize the plastics found in their environments. A study conducted by the University of Guelph, found that urban bees have begun using discarded plastics, such as disposable plastic bags, to build their nests and that some colonies utilize building materials such as caulk and sealants in place of normal plant resins. Surprisingly, no ill effects to the bees have been reported. While the findings are encouraging in that they showcase nature’s adaptability, they are alarming in that they bring to light the extent of human influences on urban ecosystems.

Urban Bees Start Using Plastic Waste to Build Hives