Thousands of fish killed in frozen Washington lake

[deminks]

http://www.sunderlandecho.com/news/local/thousands_of_fish_killed_in_frozen_washington_lake_1_2956288

THOUSANDS of fish have died after suffocating in a frozen lake.

The fish are thought to have been starved of oxygen after ice up to 18 inches thick formed at Mount Pleasant Lake, Fatfield, Washington, during the extreme cold spell over Christmas and New Year.

The Washington and Harraton Angling Club, which leases the site from Sunderland City Council, only recently made the shocking discovery after the slow thaw.

(snip)

“Nobody realised how thick the ice was. It’s only been in the past week or so that we’ve been able to see through it.

“We now think it was up to 18 inches at one point.”

Mr Smith, who lives nearby and has looked after the lake for more than 30 years, said he had never witnessed such a scene at the site.

(end snip)

[RegieRocker]

1. The oxygen crisis

Could the decline of oxygen in the atmosphere undermine our health and threaten

The rise in carbon dioxide emissions is big news. It is prompting action to reverse global warming. But little or no attention is being paid to the long-term fall in oxygen concentrations and its knock-on effects.

Compared to prehistoric times, the level of oxygen in the earth's atmosphere has declined by over a third and in polluted cities the decline may be more than 50%. This change in the makeup of the air we breathe has potentially serious implications for our health. Indeed, it could ultimately threaten the survival of human life on earth, according to Roddy Newman, who is drafting a new book, The Oxygen Crisis.

I am not a scientist, but this seems a reasonable concern. It is a possibility that we should examine and assess. So, what's the evidence?

Around 10,000 years ago, the planet's forest cover was at least twice what it is today, which means that forests are now emitting only half the amount of oxygen.


Read the rest here
http://www.guardian.co.uk/commentisfree/2008/aug/13/carbonemissions.climatechange

[MineralMan]

3. No. That isn't the cause.

[RegieRocker]

8. First you don't know the depth of the lake

and if you had read the article it's never been seen before. Where as you stated it's a normal occurrence where you live. Lastly it is due to lack of oxygen.

[MineralMan]

13. Yes, it's due to a lack of oxygen, but not of atmospheric

oxygen. As for your other statements, I have no comment. I did read the article. It hasn't been seen for 30 years. That's also common. Lakes don't winter kill every year, even here in Minnesota. There are many factors that influence whether winter kill happens or not. Eutrophication is the main one. Overgrowth of algae and other aquatic plants is a common cause. When they die off in the winter, their decay can reduce total dissolved oxygen levels in the lake. If overgrowth happens, as is common enough around lakes with lakeshore human population, thicker ice for a single winter can cause winter kill.

You see, this is a subject of interest to me, so I've actually studied the mechanisms that are the cause of winter kill. You could look up some of the same information and discuss the subject as an informed person, too.

[Name removed]

16. Deleted message

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[MineralMan]

18. And you missed the point that the lake is in England.

They've had a very harsh winter in Northern England, where this lake is located. It's caused much thicker ice than normal. That's what happened.

As for real life, personal observation, I've been observing lakes and rivers all my life, close-up. I'm an avid angler, so it's important to my success. I've seen winter kills.

[RegieRocker]

23. So have I and where I live I have never seen a mass

fish kill ever except after being stranded after a flood. I fish also. There fact it is in England is irrelevant, water freezes at 32 degrees. The point is the fish kills. Once again you missed the point "Depth". If it's a shallow lake then that would lead to a low oxygen level. If it's a deep lake then I really disagree with you and your perception is skewed by your environment. The real point here is not if the oxygen level drop was caused by ice, vegetation etc. I'm not the op. The real point that you missed, is that since the atmospheric oxygen levels have dropped then common sense dictates that water oxygen levels would also drop. Why the aeration if that wasn't true? You need to read the article I posted. Maybe that is your confusion and the fact that I'm not the op.

Let me put it this way:

Brazil a huge 100 ton fish kill leaves hundreds of fishermen destitute. Brazil is in mid-Summer. Mass fish kills have been happening all throughout the year, just because it's winter and ice is forming is not the answer for all cases, that was the reason depth is so important. You don't know the depth and neither do I, so you can't discredit it before knowing, which is what you did. My guess is this lake is shallow by it's location but unable to find info to say either way. Doesn't seem to stop you though. Have a nice day.

[MineralMan]

24. Winter kill doesn't exist where you are. Nothing freezes that deeply.

Where this lake is, it does. It's on the northern border of England. This winter is colder than normal there. Abnormal conditions cause things that aren't usually seen. This fish kill is due to the thick ice and cold weather. Abnormal conditions for that place. Oxygen levels in the atmosphere have not dropped that much in recorded history. Check it out. Yes, many millions of years ago, they were higher. They've been stable for a long, long time at the same levels as we have today. If that were not the case, things would be much worse.

What has changed is that humans are putting lots more nutrients into our waterways. That encourages overgrowth of aquatic plants. When they die in the winter, decomposition lowers the oxygen content of the water. If it goes too far, fish die. It is that simple. Atmospheric oxygen levels have nothing to do with that. Add to that the extremely cold conditions this winter in that part of the world, and the ice got thicker, exacerbating the problem. It was too much for the fish, which survive in a very narrow range of conditions during the winter there. They died.

And so it goes. Go look at the map. That area is surrounded by farm fields. Farm fields = fertilizer. Nutrients that drain into the local waters. There's a simple explanation for this.

[RegieRocker]

25. Actually I have seen more fish kills in August

than any other times of the year. When a lake turns over.

[MineralMan]

26. From the Michigan DNR - Info on summer fish kills

Summer Kill

Summer kill occasionally occurs in lakes and streams during extremely hot summer weather. High temperature and low dissolved oxygen combine to stress the fish. Most prone to summer kills are pike, perch, suckers, bass, and bluegill living in shallow, productive lakes or bays with excessive amounts of algae or rooted aquatic vegetation. The plants consume large amounts of oxygen at night, causing a temporary shortage of the vital gas just before dawn. A cloudy, calm day extends the critical period by reducing re-oxygenation from photosynthesis and wave action. Apparently, fish in the oxygen-depleted areas do not sense the danger and swim to safety in time.

Summer kill may also occur in deep, unproductive lakes containing trout or cisco. These fish require both cold and well-oxygenated water. During summer they seek refuge in the cold bottom layers where temperatures are less than 72 degrees F. Death results if the oxygen level there declines below about 4 ppm. Trout will also die in streams if they are unable to find cold spring water. Several stream trout mortalities were reported during the hot summer of 1995.

A very unique type of fish kill is caused by a lightning strike on water. Death occurs immediately. Large fish, which draw more electricity than small fish, may be killed selectively.

In conclusion, the risk of some types of fish kills can be reduced by keeping as many nutrients out of the water as possible. Sources of nutrients include septic fields, fertilized lawns and farm fields, and wastes from livestock and waterfowl (including tame geese). Reducing nutrient input starts the following favorable chain reaction: production by aquatic plants is reduced, less decomposition is required, and oxygen will not become depressed to critical levels.

Natural fish kills are obnoxious, and may affect fishing and predator-prey "balance" for years. However, they are often not serious in the long run because lakes contain thousands of fish per acre. They may be thought of as nature's way of thinning out fish populations. Usually, fish kills indicate that the habitat is of marginal quality for certain species because of the broad range of weather conditions we experience in Michigan.

Infrequently, fish kills indicate habitat or pollution problems we may be able to correct. And sometimes, fish kills beneficially reduce over-populated, slow-growing panfish and actually increase growth rates and improve fishing.

[RegieRocker]

27. No mention of lake turnover

do you even know what that is without looking it up first? I doubt it.

[MineralMan]

28. Of course I know about lake turnover. And, no, they didn't mention

it. Here, it happens in the Fall, not the summer. Fishing gets crummy for a while. Not all lakes experience turnover, either. Anyhow, I see it every year. Some fish die every time. Most do not. After a few days, fishing returns to normal.

[RegieRocker]

32. And of course I know when a body of water freezes

it is unable to receive oxygen from the atmosphere. My point was and shall remain that atmospheric oxygen levels have dropped and this could account for this occurence and many others. Also disease for both man and animals.

[EstimatedProphet]

34. In MO (where I went to college BTW) lake turnovers are a spring phenomenon

[RegieRocker]

36. You're obviously misinformed.

Lake turnover happens in the spring and the fall. It is in the fall when you might see dead fish from it.

[EstimatedProphet]

37. Which is why I find it hard to believe you see it in August.

I know about fall turnover. I know that it happens in the fall. August in MO is too early for fall turnover typically.

[Odin2005]

31. what a bunck of scientifically ignorant bullshit.

The oxygen level is 21% of the atmosphere everywhere.

[EstimatedProphet]

33. "I am not a scientist"

I am. I have a doctorate in fisheries parasitology.

If a lake completely freezes over with an 18 inch cover - especially if freezes like this are very unusual, as they would be in England, there is going to be a fish kill.

[MineralMan]

2. Winter kill. Here in Minnesota, it's a common thing, since many

of our lakes are quite shallow. The little lake near my home has an aeration system that runs all winter. It even keeps a small area of the lake ice-free most of the time.

[PBS Poll-435]

4. But don't you have like 10,000 lakes?

How can you keep them all ice-free?





:P

[MineralMan]

6. Most lakes don't have aeration systems. A lot of smaller

lakes experience winter kill every few years. It just depends on how severe the winter is. Deeper lakes don't have the problem, although a certain number of fish in every lake don't survive the winter. It's nature's way of limiting fish populations.

Actually, we have about 15,000 lakes or so, depending on how you define the word lake. My definition is different from the state's definition, though. I differentiate between lakes and ponds at about 20 acres. The state calls bodies of water lakes at a smaller size.

Anyhow, here in Minnesota, winter kill is just part of the winter. The lakes that are aerated are generally lakes in our cities that are important for recreational fishing. Those get aerated. Outside of cities, though, smaller lakes don't get aerated. It's expensive.

[PBS Poll-435]

10. Thanks for the info

I am sure that you can tell that I was kidding, but I appreciate knowing a little more about Minnesota.

Here in Texas, We have 1, yes count it 1 natural lake.

:D

[MineralMan]

14. Texas. It's a whole other country, I hear.

Minnesota is truly blessed with lakes and other freshwater resources. It's a wonderful place for an angler like me, despite being frozen over for several months. I don't ice fish.

[PBS Poll-435]

15. Funny story...

When I was a young'un a fish took my fishing pole when I lived in the PacWest.

There was a drought through the winter.


Went back to the lake the next season and found it laying on a sandbank.



:woohoo:

[MineralMan]

19. Cool. It's rare to find a lost fishing rod.

[sufrommich]

35. That's how Minnesota got the title "land of a thousand lakes"

instead of Michigan, it counts ponds as lakes.I only mention this because my Dad will argue this fact to anyone who dares say that Minnesota has more lakes than Michigan,it's a matter of great importance to him,lol. Did you know Michigan only has one county in the whole state that does not have a lake? I can't remember which one it is though.

[Enthusiast]

5. Ohio too.

In smallish man made ponds, mostly. We have very few natural lakes here.

[MineralMan]

7. The northern part of Minnesota is pretty much one big swamp,

with lakes where there are low places. The glaciers of the ice age are responsible for our terrain. We have natural lakes over the upper 2/3 of the state. Southern Minnesota, on the other hand, has far fewer natural lakes.

[Crystal Clarity]

9. Wow they must be very shallow lakes then.

18+ inches of ice is common here. Rare to see less then that. I've never heard of it causing fish kills here.

I guess I'll need to go back and read the entire article to find out what's up w/the lakes in Washington State. It seems as if there's got to be more to this...

[RegieRocker]

11. I've searched high and low for the lake depth but

unable to find. That would be important.

[Crystal Clarity]

12. Yes it would be important to know

They mentioned Carp, Roach and Eels... I don't know about the first 2 but the latter are usually shallow water fish. Still odd imo though

[MineralMan]

22. Now that we know this lake is in England, it all makes sense.

I wondered about the loach and eel thing in the article, so I did a little checking. This winter has been very severe and cold in Northern England, where this lake is. It's no wonder they haven't seen this type of winter kill there for decades. It's not one of those "disasters" everyone seems to be seeing everywhere. It's just a really cold winter that froze the lake more this winter. Too bad for the fish and the anglers, but it'll recover in time.

[Crystal Clarity]

29. Kind of off topic but what I've always found interesting

is the relatively mild climate the UK (usually) has. Check out the latitudes! I've read somewhere that it has something to do w/the gulf stream. I wonder if global warming may adversely affect that someday?

Geographic Coordinates
Latitude/Longitude (Absolute Locations)
London: (capital city) 51º 30' N, 000º 10' W
Belfast: 53º 35' N, 005º 55' W
Cardiff: 51º 30' N, 003º 13' W
Dover: 51º 08' N, 001º 19' E
Edinburgh: 55º 57' N, 003º 13' W
http://www.worldatlas.com/webimage/countrys/europe/uklatlog.htm

[MineralMan]

30. I know. It's pretty far north to be so moderate.

Ocean currents are the reason, from what I understand. And, yes, if those currents are altered by climate change, they may be in for some difficult winters. In fact, the past two years have seen some colder than usual weather in that area. This year, especially, they've been talking about unseasonably cold weather in Europe and the British Isles. A similar cold snap happened in the same area in the early 1960s, though, so it may just be a weather fluke. I don't know.

We're having an extra snowy winter here in Minnesota this year, too. Depending on what happens in February and March, it could be a record-setter. Same with the Northeastern US. Lots and lots of snow.

Weather or climate? Who knows. Time will tell the story.

[MineralMan]

17. Ha! This lake is in England, not Washington State in the USA.

The site the article is from is a British Site. Hilarious.

Fatfield is a suburb of Washington, near Sunderland, which is on the North Sea, just south of the border of Scotland.

They've had a very cold winter there, far colder than normal. That's why a winter kill hasn't occurred in decades.

[Crystal Clarity]

20. Ha... I see that

:dunce: I didn't even notice till you pointed it out.

I wonder what their definition of a lake is then. Even yours cracked me up. Of course there's always the possibility that you are right and we are wrong terminology-wise. ;-)

I don't want to give my specific location but will tell you that I live on a Pond and here are it's stats:

Length of Pond: 5 miles
Width of Pond: 1.5 miles (at widest pt)
Depth of Pond: 180 feet (at deepest pt)
Surface Area: 1,568 acres

[MineralMan]

21. Oh, that'd certainly be a lake here. My favorite fishing lake is

only 2000 acres, and it's definitely a lake. There's a little 60 acre thing near my house. It's called a lake in Minnesota. Anywhere else, it'd be called a pond. It's aerated to prevent winter kill, and is chock full of fish. Great for taking kids to.