Tag Archives: Russell

Salmon hatchlings use geomagnetic field to learn which way is up

Researchers have known for years that salmon use the Earth’s geomagnetic field to guide their migrations, now it has been found out that when the young emerge from gravel nests they use the field to tell them which way is up.

The salmon’s use of the geomagnetic field is important to understand in terms of how salmon navigate across a wide range of habitats. From early in the life cycle the field is important to the fish. This matters because we need to know how rearing conditions might impact the fish, particularly in the case of hatcheries. In hatcheries there has been some evidence that exposure to unnatural magnetic fields can disrupt the ability of steelhead trout to orientate properly. 

Research has shown that in the magnetic sense salmon can be used for 3 dimensional orientation..as a map, a compass, and an indication of which way is up.

At spawning the females bury their fertilized eggs in the gravel. Upon hatching they remain in the gravel until they deplete their yolk sacks, then they emerge into the open water.

The hatchlings appear to use the electromagnetic field lines to determine which way is up. The magnetic cues are used for 3 dimensional orientation across a wide spectrum of spatial scales and habitats. In previous studies the importance of light, temperature, and current were considered on the hatchlings…all could be used by the fish , but none was essential because in the absence of these clues the fish still moved out of the gravel.

Researchers set up experiments using copper wire coils to simulate an electromagnetic field. Experiments were carried out in darkness and no current. The group of salmon that were exposed to the normal magnetic field moved significantly more than others that were exposed to different conditions.

The conclusion is it seems like salmon use the direction of field lines to orientate vertically during their emergence from the gravel.

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The Old Water in the Newspaper Trick Revealed

The weekend is here…challenge your kids to learn this “magic trick”. Good family fun and kills some time.

Protecting Hawaii’s Water Supply.

Recently in Hawaii a group of conservationists made their way through the bog and difficult terrain of the Ka’ala Natural Area Reserve. Their purpose is to reintroduce Native plants to the rainforests, in turn preserving the freshwater.

The water supply in O’ahu has been cut in half in the last 100 years.

That group of conservationists was heading to the highest point on O’ahu to scale down the steep ridges and find places to plant one of Hawaii’s most endangered species…the kamakahala.

 

The Native Hawaiian forest holds water better than any other forest in Hawaii. In areas of non native forest rain goes right through it and washes the soil away. Native forest traps the water, slows it down, and it gets the chance to percolate into the aquifer where it can be harvested for human use.

Planting native species like the kamakahala is very important to restoring the forest. It is an example of the beautiful native trees and mosses that are the sponge of the local rainforest that work together and provide the fresh water humans require. These plants and tress work in conjunction with each other, if one is missing , problems arise with others.

The experts say that protecting mauka forest areas is the most cost-effective and efficient way to absorb rainwater and replenish groundwater. The less water there is the more expensive it is to harvest, pump it, and supply it to everyone. Without the water there is no agriculture, no economy, no tourism. No one can live without it.

The forests are so critical to the Hawaiian water supply there is even an ancient proverb to describe the relationship. Hahai no ka ua i ka ulula au…meaning ” the rain follows the forest”.

The conservationists want to make sure there is plenty of water for future generations. Water is the source of life and being stuck out in the middle of the Pacific Ocean they have to take very good care of what they have.

The EPA Blocks Obama Era Clean Water Rule.

Trumps administration has formally suspended a major Obama era clean water regulation ahead of plans to issue its own version of the rule later this year.

The bitterly contested rule known as Waters of the United States was once called by Trump as one of the worst examples of federal regulation. The legal process for removing the rule began soon after Trump took office and it is to be replaced by a more industry friendly alternative.

The head of the EPA, Scott Pruitt , has filed the legal docs to suspend the Obama era rule for two yrs. Pruitt is now developing a new water rule which is expected to include much looser regulatory requirements on how farmers, ranchers, and real estate developers must safeguard the streams and tributaries that flow through their properties and into larger bodies of water.

The Obama ers rule limited the use of chemical fertilizers that could run off into small streams. Rural landowners don’t like this and are also a key component of Trump’s political base. It was a rule popular with environmentalists , but viewed as an infringement on the rights of the farmers, ranchers , and real estate developers.

The National resource Defense fund will be challenging this new rule in court to protect the old rule….this one issue will be interesting to watch unfold as America tries to find the balance between the developers and the environmentalists.

Ocean Circulation and Rainfall Are Linked

 

Researchers have found that changes in Ocean currents in the Atlantic Ocean influence rainfall in the Western Hemisphere, and that these two systems have been linked for a very long time. These findings are important because if we can understand the past it could help us how these same factors may influence today’s climate and the future.

The Atlantic Ocean surface circulation and how it changes has implications  for how rainfall changes on continents. The Atlantic Ocean has an effect on the World’s climate by moving warm water from the tropics to the poles.

The base of the research involves studying three sediment cores taken from the seafloor of the Gulf of Mexico. The samples give insight into factors that influenced the strength of the ocean current in about 30 yr increments going back some 4,400 yrs. by going back in 30 yr increments the question they asked was what can those reconstructions of temperature and salinity tell us about the greater Atlantic Ocean surface circulation.

The data shows that in comparison to today, the Atlantic Ocean surface circulation was much weaker during the Little Ice Age, a cool period from 1450-1850 thought to be triggered by volcanic activity.  Since this set of currents are known to influence global climate, researchers were interested to see if there was a correlation with rainfall in the Western hemisphere, and how this could change over time.

To assist in solving this question the core data was compared with data from tree rings, cave formations, and other natural records. For modern correlations they compared data collected by humans during the last century.

The results show that in present and past the Atlantic Ocean surface currents correlate with rainfall patterns in the Western Hemisphere. This is important for two reasons . There is a correlation between current and rainfall patterns, and the correlation is evident over time. The findings emphasize  the importance of the Atlantic Ocean surface circulation to rainfall, and that changes in current can have far-reaching impact. therefore future changes in the gulf of Mexico’s salinity and temperature could be expected to influence the climate in other ways.

Federal Government Seeks Input on Ottawa River Watershed

The Federal Ministry of Environment and Climate Change Canada has begun a study on the Ottawa river watershed, and wants input from Canadians on the initiative.

MP David McGuinty says that the Ottawa River is the jewel in the crown of the Capitol Region. Our history is built around it, for economic, ecological, and cultural well-being. So it is important how we manage the watershed as best we can.

A healthy watershed is important to the economic, ecological, and cultural well-being to the people who live around it. The input from Indigenous peoples, local citizens, and organizations is important as it will feed the study with the information about the Ottawa River watershed, and how best to protect, manage, and conserve it.

If you want to join in the conversation on the Ottawa River Watershed Study visit the website PlaceSpeak. Information and questions will be updated as the study progresses or by attending the public meetings to be held in the National Capitol Region.

Thursday, Feb. 8, 2018, at 90 Elgin Street, in Ottawa. 4:30-8:30 pm.

Thursday, March 1st, 2018, at 25 Laurier Street, Gatineau. 4:30-8:30pm

The Minister of Environment and climate Change, Catherine McKenna, says she is committed to protecting Canada’s freshwater resources. she encourages everyone to participate in the Ottawa River Watershed Study.

The Ottawa River Watershed is on of Canada’s largest watersheds, covering more than 140,000 sq. kilometres  containing more than 200 municipalities, holding more than 2 million peoples.

Cape Town To Run Out Of Water Within Weeks

One of the world’s most popular tourist destinations, Cape Town, is facing a situation where residents could be forced to line up for water by April as the city fights the worst drought seen in 100 yrs.

Within months South Africa’s oldest city may become the world’s largest city to run out of water. tight water restrictions are presently in force with a restriction of 50 liters a day per person. The water restrictions have been  brought in to delay what has become known as Day Zero..April 12. This is the day the taps will run dry.

With usable water levels in the dams at 17.2 % at present, when the levels drop to 13.5% the city of 4 million  will be forced to line up daily for a ration of 25 liters from 200 collection points.

The police and army are on standby, prepping for the unrest that will surely come. The city’s mayor, Patricia de Lille, said warnings to use water sparingly have fallen on deaf ears. Despite the cities best efforts 60% of Capetonians are callously using more than 87 litres per day….as Day Zero looms. An extra tax for abusing the water is to be voted on.

Nobody knows what to expect when the water runs out.