Hi everyone,
About a month ago while using Google Webmaster Tools to try and resolve an issue involving Pinterest I stumbled across something that I'd call somewhat of a rankings Quirk. I posted about my issue over in the Pinterest forum but discovered that the quirk was fairly serious with the potential for abuse afterwards so I asked the mods to delete that post. incrediBill got back to me and suggested that I could go ahead and write about it because if I found it it was likely others had too and may be abusing rankings and/or competitor sites with it, it has that potential and I could warn others. If, after reading this, mods find it against TOS feel free to delete the post. I did report the problem to Google but haven't heard back so...
The quirk, short version: many pages don't appear in image search results AND web search results at the same time for a given querie, even if they are ranked for both . I'm not the first to notice that happening, example:
https
://productforums.google.com/forum/#!msg/webmasters/dZO21ABrbDQ/5tnHHeSGZvkJ
(Mod's note... paste ^^^^ Google link into address bar. It breaks in our forum's redirect script). Long version(incl why it's a problem with potential for abuse): Visit your Google Webmaster Tools account and select the "Search Traffic > Search Analytics" section of your dashboard. On that page go over to the "search type" area and select "comparison" as your search type and set it to "web vs image". Next toggle the column header and find a page receiving both image and web impressions.
Head over to Google and look for that querie in a web search and it shouldn't take you too long to find a querie in which GWT says your site is ranked in web results but you cannot find it there, but you do find it in image results. This does not affect all urls, especially high authority pages or pages that appear grandfathered into the top spots, but it does affect a surprising number of pages on low to mid level sites. I even found pages with no image impressions appearing in image results and not web results(and vice versa) but it's easier to find them if they get both. The problem: These pages are not appearing in one type of search if they are appearing in the other, and they fluctuate back and forth. More specifically, they are indeed blocked from one set of results if appearing in the other.
Surprisingly this seems to happen more often to pages that have a top ranked image for any given querie and so they appear in the "related images" section of a web(text) search which blocks them from getting a textual link in that web search. Again, this is not 100% of the time but i'm finding it on a surprising number of queries.
How I found that a blocking effect was happening: Someone pinned an image on a page that I used to get good web traffic to and, instantly, I began getting very little traffic to the page. After investigating I found my image on Pinterest, as well as now being top ranked for that image in Google image search, so getting almost no traffic didn't make sense. I was quite surprised to find that the page was suddenly NOT ranked in web results anymore, only in image results. I resolved the image issue by replacing the image with a different one and after some time the traffic returned from web search(much better CTR in web searches for this page) and the original image now ranked for Pinterest in the same spot it had been ranking for me.
I went through hundreds of queries in my GWT dashboard and sure enough, where I found a highly ranked image I did not find a web result at that time. This didn't affect all of my pages/queries but a surprisingly large number of them showed this problem. Too many in fact to be a "ranking fluctuation" issue, the site is over a decade old. More frustratingly is that the problem itself fluctuates. A search 4 hours later might find the page is ranked for web results again but the image is nowhere to be found in image results. More commonly the fluctuating happened more slowly, 7-10 days or more between switches. There seemed to be a very real blocking effect going on.
I confirmed the blocking by removing images and waiting, sure enough the pages eventually became web ranked again, with traffic.
Potential for abuse: I hesitate to write this part but you might do well to see if it's being used against you. Theoretically: a page you own ranks #5 in web search results and the page in spot #4 has an image. You submit the image to somewhere google trusts, like Pinterest, and it's likely that either that image receives a better ranking OR the pinterest version replaces the 4th place image and credits the pinterest version for it. Either way since a credit link appears on pinterest and, I'm assuming, some small amount of a ranking signal is created, the page in #4 suddenly has a better ranking image that Google may choose to display in image results and.... *poof*, the #4 web(text) result is gone, you are now #4(at least for some of the time, it fluctuates back and forth). I'm not even sure how a competitor could detect that actually, image search is updated much more slowly.
Go ahead and search your own GWT account if you have images on a lot of pages, wherever you have an image appearing in image search check web search to see if your page appears there too. I know mine isn't the only site with web search results that don't match what's reported in GWT but I'm curious as to how many other sites rank for a web querie but can't be found when you search for it. I hope I explained this sufficiently for you to do some research on your own site(s).
[edited by: Robert_Charlton at 8:55 am (utc) on Jan 28, 2016]
[edit reason] Delinked Google link so it could be pasted into address bar. [/edit]