Brook Trout Habitat

[wtsobsessed]

The Eastern Brook Trout coalition has been busy compiling GIS data on the extent of Brookie habitat. This data is just starting to dribble out. I've been able to create a series of maps which show the extent in some detail

For MA, it's another view similar (perhaps more accurate?) than the NHESP view.

For neighboring states, particularly NY, RI, VT and NH, it's the first comprehensive data I've found.

If you go to www.wildtroutstreams.com, and click on streams, you can get to these maps from the appropriate state, or click on "brookies" to see an overview and links to all of the brookie status maps.

[dw]

I like your project, but there are some glaring errors on the Vermont piece. For example, your map shows Deerfield River below Harriman Reservoir as greatly impaired brook trout water. But this is one of the most abundant populations of brook trout I've ever heard of and it is well documented.

If you want to email me I think I can help you out with information. A study was done recently comparing brook trout population in Vermont in the 1950's with recent times. No real change was seen. The number of fish 6" or greater has slightly increased, yearlings under 6" have decreased and reproduction has greatly increased. The study was done using 1 run electrofishing and similar stream lengths to compare apples to apples. Vermont has also done recent assessment of wild rainbow trout which had much more mixed results.

[wtsobsessed]

dw said:

I like your project, but there are some glaring errors on the Vermont piece.

Thanks for the comment. The maps are generated from a database created by the Eastern Brook Trout Coalition.

I speculate there are two possible reasons for the problem you note:

1) The database is in error (this happens); or,

2) An alternative explanation, given that every stream within a sixth level watershed is coded the same way, is that the brook trout within the rest of the watershed (exempting the Deerfield itself, which is only one stream), is impaired.

The maps are made from the current (beta) release of the web viewer. The originators comments that data is still being cleaned up, so it's possible they'll correct it on their own.

I'm not directly involved in the project, nor do I originate any data, I'm just making maps from what I find. But I'd be happy to pass on the information you have, since I know how to contact them.

[dw]

Taking into consideration all water in a given portion of a watershed, the map is still problematic. If you're interested we can take it apart stream by stream.

[wtsobsessed]

I'd be interested in taking our discussion offline, and then posting a conclusion to the group.

As I thought about it more, the encoded areas are "sixth order" basins. The Deefield is probably a second-order stream, i.e. 0-Ocean/1-Connecticut River/2-Deerfield River

So the colors can't be coding the condition of the Deerfield.

But frankly, since I haven't fished ANY of these streams, I couldn't tell you what the maps really mean on the ground. I'd certainly be interested in understanding that much better.

[dw]

I'm gathering no moss today, but I may be able to take a closer look tomorrow. Feel free to email me.

[wtsobsessed]

The mapping viewer which generated these maps is now "publicly" linked...it still claims to be in "beta" release, and there's still language disclaiming the data (for scientific use)...but its now linked to a readily available site.

If you go to TU's brookie site:

www.brookie.org

then hit the "maps" tab. The maps I generated were all using the "advanced" web viewer.

The person responsible for the mapper is a US Forest Service biologist named Mark Hudy...

You can reach him at [e-mail]

I would suggest that any concerns with the accuracy of the data be sent directly to him.