Webmaster Tools and non-search traffic... interesting comment

[rlange]

In the Big traffic change for top URL but DECREASE (not yay) [webmasterworld.com] thread, Sand made the following comment:

Sand wrote:
I recently got this message -- for years, we had included a link to a certain page in every email newsletter we sent out. A month or two ago, we decided to stop including that link in the newsletter. Since email was the only real traffic driver to the page, visits slowed to a trickle.

Google Webmaster Tools alerted me to the traffic drop, so I can say with certainty that this alert doesn't necessarily have anything to do with organic traffic.

I find this fairly interesting. I was always under the impression that Webmaster Tools' "traffic monitoring" involved search only, but this seems to indicate that Webmaster Tools is aware of non-search traffic, too.

The only real explanation I have is that the Webmaster Tools property is linked to the Analytics property (Sand can obviously confirm or deny this). Webmaster Tools, through Analytics, noted the drop in traffic and sent the notification.

Are there other possibilities I'm missing?

--
Ryan

[Sand]

At one time it was linked to Analytics, but that was a couple years ago. The site now uses Site Catalyst.

I've also wondered about how they might be detecting this. One guess is that they're collecting visit data from Chrome or people with the Google toolbar installed.

My next idea is a little bit more tin foil hat, but I do wonder if it's possible that links clicked in Gmail are taken into account (since a newsletter was the previous traffic driver, that *might* make sense).

One more tin foil hat idea: We do use Doubleclick ad server and participate in the Google Ad Exchange. I wonder if those ad networks are able to communicate with Webmaster tools somehow? Those platforms would be able to detect a big drop in ad impressions, and could potentially provide important usage data.

All I can say for sure is that organic traffic to this particular page has been consistent but is relatively low -- unless you account for email traffic, it's definitely not enough that it could be considered a 'top URL' worth sending an alert about.

Edit: We also use the Google Search Appliance for internal search. I don't know what (if any) communication that has with other Google products.

[Planet13]

Did your number of impressions drop significantly?

They could be monitoring impressions and clickthrough rate from the SERPs without monitoring any of the other methods you mentioned.

[Sand]

Not sure -- can you see impression trends for a single page?

[Planet13]

I am not sure if WE can, but I am sure google can...