Deep Brook, Newtown

[jburrell21]

Has anyone been to Deep Brook in Newtown recently? I was there last week and the entire lower portion was choked with a green slime on the bottom. Nymphing was impossible. I don't know what Didymo looks like but this certainly resembled Rock Snot.

[jburrell21]

Has anyone been to this spot since my post? I am very curious as to what is going on there. Thanks for any input.

JB

[Steve Z]

Didymo is distinct.

It lives up to the name rock snot. Green slime with white tips. Very dense, very thick.

What you saw is probably a green algae bloom. It will look like cotton candy, fluffy and light.

Probably the result of increased nitrogen levels or some other change in water. If there is a pond upstream with a lot of ducks or geese their leavings may cause a change in the water big enough to cause an algae bloom.

Could also be a temperature thing. That particular algae might thrive at a certain temp, if so - it is probably normal for that river at that time of year. Ask a local.

Here are some pics of what could happen:
http://images.google.com/images?q=algae+bloom&ie=UTF-8&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1

In a river the bloom will usually vanish pretty quick what with the moving water. Especially since you said it was something new. Basically if the river was going to be covered in algae, it would always be covered in algae.

Trout go ahead and lay their eggs right on top of it.

I have some pics at home of a green algae bloom with trout eggs in it but I am at work right now and will probably forget to post them.

Give it some time and check it out again, it is probably already gone.

[dudley]

I fish the Quinebaug regularly
A lot of years the algae gets pretty bad, but that doesn't happen 'till mid July or later
It's the summer water temperature combined with agricultural run off that does it.
I would think it would be highly unlikely that the water temps in your Deep Brook would be high enough to cause a bloom
Not natural water temperatures anyway

[Steve Z]

I don't know a lot about algae but I a sure it is just like with aquatic insects. There are probably many many different types and even if they look alike, they may be entirely different.

I know a lot of green algae is associated with warm water temps, others may thrive seasonaly. Certain flys will spawn only in May for example even if the water temp is exactly the same in October.

I saw a green bloom the other week that was very thick. It wasn't there last summer when I discovered the river and I am sure the temp was much colder when I saw the bloom.

There was a pond immediatly upstream. I am almost positive that it coincided with the duck and geese immigration.

I bet the seasonal average temps play a role as well. Just like how commodity traders flip out when a winter is harsh. A harsh winter may kill off certain algaes entirely leading up to a light spring bloom. On the other hand a warm winter might promote a thick bloom in the spring.

Like I said, check back and see if it is still there. Ask some locals about it. They may know of a change to the river upstream that you don't know about or they may know if it is normal for this time of year.

We all have seen places that are always covered in algae and some places that we've never seen any.

[jburrell21]

Steve Z & Dudley,

Thanks for the input. I haven't been back since the post. Hopefully the torrential rain from Tuesday cleared the stream out a bit. I'll let you know what I find when I return.

JB