Why do your search engine rankings keep declining? There are many reasons that can lead to this occurrence, but one of the most common is keyword cannibalization.
Keyword cannibalization, simply put, is causing your content to compete with itself by erroneously optimizing your articles for the same or similar terms. Turning your pages and articles into competitors has an overall adverse effect on your SEO ranking, especially on a growing site. Here is an in-depth explanation of what keyword cannibalization is, and how it can be detrimental to SEO, how you can recognize it and what to do about it.
Keyword cannibalization occurs when a site has various blog posts or articles that can rank for the same search query in a search engine, either because the topic(s) they cover is/are too similar or because they are optimized for the same keyword or keyphrase.
When posts or articles from the same site are optimized for very similar search queries, they eat away at one another's chances to rank. Usually, a search engine like Google, for example, will only show one or two search results from the same domain for a query, while a high-authority domain may get three results at the most.
Think of Pac-Man gobbling up your rankings!
Keyword cannibalization generally has potentially unfavorable consequences for SEO. Various sites suffer from keyword cannibalization without the managers even being aware that anything is wrong.
They are often happy that one page is ranking in a relatively high slot for their targeted keyword without realizing that another high-authority page would probably rank higher and achieve higher conversion rates.
However, the practical consequences are quite clear: lost site traffic queries leading to the wrong page, fluctuating SERP rankings, and ultimately, lost sales.
Keyword cannibalization splits a page's CTR into multiple moderately relevant pages, instead of having a singular high-authority page. Essentially, it turns the pages into competitors and for page-views and SERP ranks.
This fluctuation in ranking often occurs alongside a change in URLs. You may have noticed that your ranking position for a keyword keeps fluctuating, often excessively. This can happen due to keyword cannibalization during which URLs are changed, and conflicting signals mean that the ranking position fluctuates as well.
Suppose one page has earned more links than another, yet there is an apparent conflict of intent and overall content quality. In that case, it can cause an evident fluctuation in organic traffic, especially if one of the URLs ranks in a prominent position for a high-volume keyword.
Keyword cannibalization causes anchor text and internal links to lead visitors to multiple moderately authoritative pages instead of a single highly authoritative page on the subject in question. In the same vein, backlinks that could go to one consolidated source of information are now split between two (or more) pages.
Keywords are one of the most important channels through which search engines understand the content of various pages. If all of your keywords are the same, the search engine, Google, in this case, tries to determine which page is the best fit – and if the content of both pages is too similar, it might get it wrong.
In some cases, the wrong URL ranks in a single product ranking for a keyword associated with a particular category or subcategory, or simply a different piece of content from the one that should be ranking — maybe one published a long time ago. When this happens, it is likely that the cause of the issue is cannibalization and that the inappropriate URL is deemed to be more relevant than the one you are trying to rank. Of course, there will be a negative impact on conversion rates if visitors land on the wrong page.
The crawl budget for a website refers to the number of times a search engine spider crawls it in a given time. The existence of multiple pages devoted to the same keyword causes the crawling and indexing of essentially unnecessary pages. While this effect could easily go unnoticed in small sites, large eCommerce websites or vendors with multiple products are more likely to notice the difference.
Multiple pages targeting the same keyword suggest that your content is most likely stretched thin and that your content can not fit your keywords on each page, resulting in a lower conversion rate. Inevitably one of the pages will convert better than the rest. Instead of leading new visitors to the page and making it the most authoritative page accessible, potential leads are lost as they land on less important sites.
To check whether or not a site suffers from keyword cannibalization, simply search the site using any keyword you suspect might have multiple results. The results from inputting "site:domain.com (keyword)" into the search engine will inform you about whether or not the site suffers from keyword cannibalism.
The findings can be checked by typing the same keyword into the search engine (Google) using a local search result checker or a private browser. Answering the question of which pages from a site are seen in the search results and which positions they rank is the next step in detection. If two of these pages rank highly, say #1 and #2, there isn't a problem for the same keyword. If they rank lower, such as #7 and #8, there is a need to tackle an obvious problem immediately.
You can also go to your Google Search Console and click on any of the query, and you can identify what pages are ranking for that query:
You might need to spend some time going through each of the keywords, so the best way is to work with the top-ranking keywords and go down from there.
With the problem identified, solving it is relatively more straightforward. Here are steps to fixing keyword cannibalization:
When the problem entails a site having multiple pages targeting the same subject while only one needs to be kept alive, the best way to address it is usually by putting 301 redirects in place. Once the strongest of the cannibalizing pages has been identified by evaluating metrics such as inbound links pointing to the pages, traffic history, and organic visibility across other terms, the weaker pages can simply be removed and their URLs 301-redirected to the retained page.
This is usually the easiest way to tackle cannibalization problems. The internal links that point to the removed pages should be updated as well, and in a few weeks, the removed URLs will be seen to drop out of Google's index.
In a situation in which you don't have the liberty to remove the cannibalized pages and retain just one for reasons that might range from the page being a dedicated PPC landing page, a great piece of content from a UX perspective, or any other reason, consider using canonicalization to resolve the problem.
Canonicalization involves selecting one page as the primary one, thus indicating that page alone as the one that should rank on the SERP, and ensuring that ranking signals such as link equity, are attributed to the canonical page. All of the pages will remain accessible to users, and none of them will be removed.
Similar to canonicalization, if you cannot delete and redirect the cannibalized pages for whatever reason, an effective alternative is implementing rel= "noindex" tags (or an HTTP Response Header) on all but the chosen primary page. This implies that all pages will still exist on the site, yet all except the primary page will be de-indexed, resolving the cannibalization issues.
However, canonicalization is used in preference to no-index because ranking signals are attributed to the canonical, while with no-index, they are not.
Another simple solution is to turn the most authoritative page into a landing page that links to other unique variations similar to the target keywords. Alternatively, suppose a landing page that consolidates all of the product pages does not exist. In that case, a unique landing page can be created to serve as an authoritative source page, and all the variations can be linked to it instead.
Two articles that are found to attract the same audience and basically tell the same story can be easily rewritten and combined into a single, fuller article. Such merging helps rankings as Google loves lengthy, well-written content while simultaneously solving the keyword cannibalization problem.
Setting up an internal linking structure to link from long-tail posts that are less important to those most important helps search engines determine the grade of the importance of each article. By following links, search engines such as Google can figure out which articles should rank highest in the search results, thereby solving keyword cannibalization problems.
The number of websites linked back to particular content is also considered by SEO when ranking search results. Other websites—especially very influential ones—creating links to less important content could cause it to rank higher than newer, more relevant content.
There are tools you can use to track the backlinks to their various websites, after which the webmasters could be contacted to request that they change or delete the links. In an ideal situation, they should exchange the old links with the new ones to be prioritized, strengthening your SEO ranking.
Finally, in a website that already has highly diverse, SEO-rich content and only suffers from cannibalization due to a poorly planned keyword strategy, all that may be needed is finding new keywords that accurately describe the pages' content.
Especially when working on a large site that has accumulated multiple cannibalization problems over a long time, fixing keyword cannibalization can be time-consuming. Still, it remains an absolutely necessary task to carry out. Because the best way to fix keyword cannibalization is to prevent it from happening in the first place, it is just as pertinent to ensure that there isn't a future reoccurrence of resolved issues.
Preventing keyword cannibalization simply involves checking your site during keyword research for previously created similar content with the same intent every time as the new content. That can be done by searching "site: [keyword]" as shown below to return a list of pages that are considered relevant to that keyword. If a page with the same intent is found, consider updating it rather than causing cannibalization issues by creating something new.
The importance of keyword cannibalization as an SEO topic is generally perceived differently, especially as Google is quite adept at deciphering the essence of the content and properly ranking it. Nevertheless, in the cases where Google might be wrong, it is important to know how to keep pages from cannibalizing one another. With proper observance, cannibalization can be effectively quashed in future cases.