Warning! Hood Canal, Low O2 - Be nice to critters!

[nwscubamom]

Last week on my dive at The Knuckle (near Mike's Beach), I noticed some signs of stress in many critters. Wolfies, normally hiding with just their heads peeking out, had about half their bodies out of their dens. They were also 'panting'. Tom and I also saw two dead octopus. And a third, out in the open (which was WAY cool, as you know).

Divers at the Yellow House and The Knuckle this past weekend noticed similar behaviors in Wolfies, and some very lethargic octopus. So while it's really really cool to be seeing so much wildlife, it's bittersweet: You're seeing them out in the open because they are desperately trying to stay alive.

PLEASE know these critters are struggling to breathe right now, and do NOT poke, or get too close to them, to the point they feel they have to move. Moving uses up oxygen.

And lest you Pacific Adventure Charters lovers (of which I am one) think this will ruin your diving up North with Don - it won't! This is only in lower Hood Canal where the problem occurs pretty regularly each fall. Go diving with Don instead!

Check out the Royal blue line - that's Hoodsport - you can see we're in deep dark doo-doo right now.



So give the critters a break!!! Once the winter storms kick in, the water will get oxygenated again, and the levels will rise.

- Janna

[Dusty2]

Sad that this occurs every year. Hopefully this rain will help get things moving again.

[Dashrynn]

Wow never thought about ocean life running low on oxygen...

[dwashbur]

Wow never thought about ocean life running low on oxygen...

Lower Hood Canal is kind of a special case because it doesn't get as much tidal movement as other parts of the Sound. I'm sure there are other factors, but that's the one I've heard the most: the water doesn't get agitated enough to dissolve as much oxygen as the critters need.

[BASSMAN]

I think someone should turn Hood Canal into an actual "Canal" I mean, how hard could that be? I bet there would be some wicked currents there if they did.

Either that, or change the name to "Hood Fjord"


It is seriously a sad thing to see, when you dive Sund Rock and the Rock fish look lost and the Wolf Eel's are laying around, out in the open and the Sea cucumbers are dying off. Normally, I would like to see more Wolf EEl's out of thier holes, but this is not fun to see when you understand what is happening. Thanks for the heads up Janna!

[Sockmonkey]

Wow never thought about ocean life running low on oxygen...

Just like in humans it's called Hypoxia. Scary stuff. Long Island Sound went though a massive bout of it in the 80's when I was growing up. You can read about it in This Fine Piece of Water (a book only an ocean obsessed long islander would enjoy... which I did)

Stupid estuaries.

[CaptnJack]

Stupid estuaries.

With a zillion failed septic systems pumping the nitrogen in!

Essentially there's:
too much nitrogen from septics leading to spring/summer algal blooms which die in the fall
a shallow sill at the bridge which restricts deep water exchange
a reduction of the freshwater input from the construction of the lake cushman dam which has reduced the "conveyor belt" flow of freshwater north on the surface and salt water "in" at depth.

There are a few other factors driving the low oxygen events but its basically a function of bathymetry colliding with human changes in nutrient parameters.

[Sounder]

Wow never thought about ocean life running low on oxygen...

I'm going to do my best to explain it, but I'm sure I've got something wrong or will leave something out... (Janna? Greg?)

Yes, there is dissolved oxygen in the water which is what the fish breathe. Low oxygen in the water is just like low oxygen high in the atmosphere.

Oxygen is kind of "churned" into the water by wind and waves. This is why there are bubblers in fish tanks - it's not really injecting oxygen into the water, it's causing waves on the surface.

In Hood Canal the water at the south end doesn't get a lot of "flushing" so it doesn't have a lot of fresh oxygenated water coming into it. This, combined with beautiful sunny summer days means there are growths/blooms of micro organisms, and these organisms consume oxygen. The algae and what not also need sun, so that's why you see there is less oxygen at 20-40 meters where the sun can reach it. It's also made worse by fertilizer from homes leaching into the water and, well, fertilizing the algae.

You can tell there is an issue, in addition to the water quality stuff (which Richard can expand on better than anyone), when the critters start to look distressed and sickly, and you'll see fish in shallower water trying to find more oxygen than where they usually hang out.

Fortunately, once the wind and rain really kicks in, it'll oxygenate the water and things will get back to normal. Some years it's worse than others, and I don't believe this is was a particularly bad year yet, but I could be wrong.

[Sounder]

Stupid estuaries.

With a zillion failed septic systems pumping the nitrogen in!

Essentially there's:
too much nitrogen from septics leading to spring/summer algal blooms which die in the fall
a shallow sill at the bridge which restricts deep water exchange
a reduction of the freshwater input from the construction of the lake cushman dam which has reduced the "conveyor belt" flow of freshwater north on the surface and salt water "in" at depth.

There are a few other factors driving the low oxygen events but its basically a function of bathymetry colliding with human changes in nutrient parameters.

You can tell there is an issue, in addition to the water quality stuff (which Richard can expand on better than anyone), when the critters start to look distressed and sickly, and you'll see fish in shallower water trying to find more oxygen than where they usually hang out.

Was writing my post when submitted his. Richard is our local water quality expert.

[CaptnJack]

Lol I can only hope. Not really an oceanographer.... Jan Newton at UW and Skip Albertson at Ecology among others are the regional experts.

But wind action is in no way adequate to oxygenate Hood Canal at depth. It helps but its more an issue of nutrient inputs overwhelming the oceanic exchange due to the sill at the bridge (which is similar to the sills at Admiralty Inlet and Tacoma Narrows). The wind combined with freshwater freshettes of the fall recirculate the water and bring it back up to moderate oxygenation for the winter, spring and summer.

In the meantime, don't play with, spook, or cause struggling critters to waste anymore oxygen/energy than absolutely necessary.

[Grateful Diver]

Mebbe we should propose sinking a ship in lower Hood Canal, running big-ass bubbler tubes down the mooring lines, and use it like a giant aquarium toy ...

... Bob (Grateful Diver)

[Waynne Fowler]

While it's a serious problem it has been nice to see that it at least 'appears' to have gotten better the past couple years.. Kudo's to Rick Mraz and those others who've been in charge of getting this problem under control.. while we've a long way to go, it's nice to see that efforts are at least beginning to pay off.

[lamont]

a shallow sill at the bridge which restricts deep water exchange.

did humans build that sill to put up the bridge, or is that a natural feature?

[nwscubamom]

It's natural, and it's a bit larger than the imagination would conjure up. The top of the sill is at 150', and then it plunges down to 500' deep. From the HCDOP website (http://www.hoodcanal.washington.edu/abo ... chure.html):

What about the water of Hood Canal?

The geology and bathymetry (underwater topography) of Hood Canal play a large role in the water quality and dynamics of how the water moves. The entrance to the canal is relatively shallow, about 150’. Just south of the entrance the canal becomes very deep, to 500 and 600’. This ‘sill’ at the entrance creates a condition in the canal that doesn’t allow the water to flow or exchange very easily with the changing tides and seasons. The ‘sill’ tends to retain the water (reduces the exchange) in the canal and estimates of complete water exchange rates are in the magnitude of years.

The water of Hood Canal can be highly stratified… which means there is an upper layer of different temperature and salinity (saltiness). Highly stratified water doesn’t mix very well. So, essentially, the waters of Hood Canal are deep, stratified, and exchange very slowly. This is not a good situation when considering the resilience of Hood Canal to human contributions.

- Janna

[CaptnJack]

a shallow sill at the bridge which restricts deep water exchange.

did humans build that sill to put up the bridge, or is that a natural feature?

hood canal, admiralty inlet and tacoma narrows sills were all created by the last glaciation

[lamont]

a shallow sill at the bridge which restricts deep water exchange.

did humans build that sill to put up the bridge, or is that a natural feature?

hood canal, admiralty inlet and tacoma narrows sills were all created by the last glaciation

damn so we can't just scooter over there under the cover of darkness and plant some limpet mines and solve the problem...

[Waynne Fowler]

[ limpet mines

Limpet's EXPLODE?

[dwashbur]

Stupid estuaries.

Stupid glaciers, carving out big uneven holes in the landscape.....

[kat]

http://www.nwdiveclub.com/viewtopic.php?f=1&t=9963

[sungurl]

How sad this happens...not something you think of unless there has been significant contamination in the water. Hope they hang on until things get better.....Thank you for helping make us aware of this...

[nwscubamom]

Kitsap Sun just ran an article on it (thanks for the heads up, Biodiversity Guy!) - NWDC is mentioned More particularly, this thread!

http://www.kitsapsun.com/news/2009/oct/ ... cientists/

- Janna

[ORDiver]

Marine life definately looked stressed on Saturday. Every wolfie I saw was hanging out and panting. We also saw one dead octo at Sund and one very stressed one at Octo Hole. Every Cali Cucumber had it's feeders out. Good diving but kind of depressing. Hope this clears up soon. We did see large school of rockfish at about 20ft. Accoring to the article (Janna) in the Kitsap Sun this should be a good sign. Let's hope so.

[nwscubamom]

Sorry to say, but that article misquoted me. :( I read that and thought, "ARRRGH!!" But what are you supposed to do?

Rockfish up shallow is a VERY BAD sign. The quote was completely backwards from what it should have been. Rockfish down at 100 feet is good and normal. When the fish move up in the water column they're trying to get the last little bits of oxygen that are in the upper part near the surface.

Thanks so much for reporting your observations. It's been an interesting year - hopefully it won't wind up in a fish kill. Keep the reports coming...

- Janna

[ORDiver]

Well thats a bummer. The rockfish seemed to be acting more or less normal. I saw lots of them in what appeared to be (from the trails of shells from them) recently vacated octo dens. I wish we could put giant flow stones with huge air pumps down there to help em out.