October was a bad month to find a retail job.

Hiring in the retail sector for last month reached its lowest since October 2011 as fewer major retailers offered large-scale hiring announcements ahead of the busy holiday season, according to data from Challenger, Gray & Christmas, Inc.

In October, retailers hired 136,700 new workers, down 8% from a year earlier. This year marked the second straight that new retail jobs declined in October, following two years of record highs for the month. Seasonal retail hiring has fallen every year since 2013. Last year, seasonal hiring dipped 10% from a year earlier.

"The shrinking job gains during the holiday season are indicative of the changing consumer habits and overall transition the industry is experiencing," Challenger, Gray & Christmas CEO John Challenger said.

That could be due in large part to the effect of Amazon.com Inc. (AMZN) . As of October 2017, there were 15.8 million Americans employed in the retail sector, down 56,000 from October 2016. During the same time, employment in the transportation and warehousing sectors surged by 111,400 year-over-year to 5.2 million as of October 2017.

"The 'Amazon Effect' and consumers' online shopping habits are definitely shifting seasonal job gains from traditional retailers to warehousing and transportation positions," Challenger said. "New technology in retail also eliminates the need for some back-office operations, which may lead to less hiring."

Here's how retailers are ramping up hiring for the holidays:

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