While doing a monthly web deep dive for one of our larger clients, we noticed a sharp decline in organic search traffic. Ultimately, our investigation revealed that paid search was cannibalizing what was otherwise “free” organic search traffic. In the end, our findings led to a clear plan of action in long term testing, deeper campaign monitoring, and most importantly, implementing impactful SEM campaign optimizations.
Paid and Organic Search
There’s no doubt that there are benefits to both paid and organic search acquisition channels. There’s a reason that paid search is a multibillion-dollar business and that SEO has long been an industry buzzword. Just like anything else in life, there’s a healthy balance between paid and organic search. On one hand, you don’t want to be displacing large volumes oforganic search traffic, but at the same time, some degree of cannibalization is inevitable (paid and organic links competing). But before we get into what is a healthy balance of paid and organic search, it’s important to understand if paid search is in fact cannibalizing organic search traffic.
Signs of Cannibalization
How do I diagnose that my paid search efforts are cannibalizing my SEO efforts? It involves (1) measuring the relationship, (2) looking for other possible causes and (3) testing the findings.
Determine the historical relationship between the business’s paid and organic search traffic. No two businesses are built the same and the relationship will vary. You’ll want to monitor how the two channels are performing in silo while also quantifying the strength of that relationship. In our case we trended visits and performance and noticed a massive drop in organic search while seeing the exact opposite for paid search. We further quantified this by running a regression on the traffic sources and found a Pearson Coefficient of -0.80 for traffic (strong inverse relationship)!
But I always remember what my intro to stats professor told me, correlation isn’t always causation! Step two is looking at other organic and paid search drivers that might validate or discount cannibalization. We looked for changes in keyword rank, consolidation in pages and any other signs of losing relevancy and nothing stood out [from organic search]. We then moved into paid search, this is where we found some gems… It was revealed spend did increase sharply, and the majority of the high performing keywords now existed in multiple campaigns across channel, suggesting that traffic cannibalization as a potential culprit of the performance decline.
Finally, to further validate our hypothesis of traffic cannibalization, we leveraged our analysis to reprioritize our client’s testing & optimization pipeline. Testing was focused on markets with high paid search saturation. In these markets, we selectively throttled back bids on keywords present in multiple campaigns. In each test, organic search traffic and conversion volumes dramatically increased when paid campaigns were dialed back, confirming our hypothesis that significant cannibalization was taking place.
From what started as an exploratory analysis on a dip in traffic, the Campfire Analytics team was able provide better optics into marketing performance and implement change to maximize outcomes from media spend. This example shows that ideas alone are ineffective without educated action. Specific recommendations and optimizations below.