More product searches are starting on Amazon.com Inc. than anywhere else, and if online retailers want to stop that shift and keep or woo shoppers to their sites, they need to focus more on personalization.

That’s according to a just-released study from search technology vendor BloomReach Inc. which studied the online shopping habits of 2,000 consumers in the U.S. The report found that 44% of those shoppers begin their product searches on Amazon, No. 1 in the Internet Retailer 2015 Top 500 Guide, compared with 21% who went directly to another retailer’s page. 34% of all shoppers start their product searches on search engines. That 44% is up significantly from this time last year, when 30% of all product searches originated on Amazon, according to a study from Forrester. BloomReach does not have data comparing this year’s percentage of product searches that originated on search engines to previous years since this is the first year they conducted their study.

“This has a correlation with the rise of mobile because Amazon has done a very good job with search and discovery on mobile,” BloomReach marketing chief Joelle Kaufman says. “They are capturing the lion’s share of mobile revenue. Consumers said they start on a cellphone and they use it as a research tool. But 81% want to buy on that laptop/desktop.”

Research shows retailers are taking notice.

BloomReach surveyed 500 digital retail marketers and found that more than twice as many of them (44% versus 20%) considered Amazon a greater threat to their bottom line than another competing retailer.

“Retailers are having a harder time getting you to go direct to them,” Kaufman says. “This has to do, I’m sure, with the amount of noise in the market. Every technique that you have to engage a customer is easily copied.”

BloomReach’s data also showed that 87% of shoppers surveyed cited personalization as a key factor in whether they spend more with a retailer.

“The consumer is telling us exactly what they want,” she says. “They want retailers to personalize the experience for them. Google is influencing what they expect from retailers, and they expect dynamic, personalized, relevant search results.”

Top500Guide.com data shows that BloomReach is the search engine marketing vendor for 26 retailers in the Internet Retailer 2015 Top 500. Those merchants did $29.240 billion combined in online sales in 2014.

Kaufman says investing in content is key for retailers who want to beat Amazon to the punch when consumers search for products.

“[Retailers] have to think about how they are ensuring that their content is unique to their brand and very well-structured for organic discovery,” she says. “If you deliver a great experience, you’re building a trusted relationship with the consumer that will lead to further purchases and further engagements.”

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