Organic search traffic is dropping since September

[teddef]

We own a large wiki site which allows people to make articles about their business and other things that Wikipedia would prohibit. To make our site more rich and expand the pages people can link to on their pages, we scraped between 1-2 million pages from the english wikipedia, pages such as “Los Angeles, CA” and “United States” etc.

We’ve been getting a steady supply of organic backlinks from users who create their own pages and cite their wikis on their website, in news etc. However, starting 2 months ago our organic traffic has started slowly decaying as if we have received some kind of algorithmic penalty.

What could it be? Could it be dupe content from the wikipedia pages we imported and indexed? Could it be some kind of algo from the Penguin update?

We are just very confused why our organic search traffic would begin to drop at all since every day we have organic users making quality pages, some of whom organically backlink their articles on their own website and these obviously add up over time.

[DonnaDuncan]

"_Could it be dupe content from the W_ikipedia pages we imported and indexed?"

That's not a good idea. I'd either point to the Wikipedia pages themselves, noindex or canonical them (back to their source).

Also, agree with Clayton John. It could be any number and/or combination of factors. Glenn Gabe, president of G-Squared Interactive, watches website traffic trends and fluctuations and comments upon possible root causes. He remarked back in November that "The fall of 2016 has been one of the most volatile ones I have seen in a long time algorithm update-wise" and observed that Google is testing its new mobile-first ranking algorithm. Check out that article to get some other suggestions as to possible root causes.

[ClaytonJ]

It is difficult with the limited information to respond with any deep insights.  Your webmaster tools data should tell you the story. If you do a last 28 days (or 45 days) comparison with only clicks - it gives you a click differential per page and you can also do the same per query.

Then cross analyse the pages or queries against positional changes.

It could be seasonal... alot of clients traffic drops late November and does not kick back in until late Jan... Start with the basics get granular and identify the exact pages and queries that are being effected, and dates impacted, then cross reference against positional changes. That should help in identifying the problems pages or queries. The backtrack at what occured about that time, google updates, sites changes etc.

Hope that helps.