Employees assist shoppers at the check-out counter of a Toys R Us store ahead of Black Friday in 2014. (Photographer: Peter Foley/Bloomberg)

While you are still enjoying the last gasps of summer weather, the nation’s largest retailers and shippers have already begun their hiring sprees for the Christmas shopping rush.

The retail industry is expected to add 755,000 temporary workers during October and November, about as many as they hired last year. But this year, filling certain positions could be tougher, industry analysts say.

An improved economy may encourage consumers to ramp up their holiday shopping, but the growing popularity of online shopping and the rise of profit-eating free-shipping polices is also forcing some retailers to change up their hiring strategies.

Target said it would  hire about 70,000 store workers for the third year in a row. Department store chain Kohl’s is expecting to hire 69,000 workers, slightly more than the 67,000 it aimed for last year. Toys R Us is poised to bring on 40,000 workers this year, fewer than the 45,000 it hired last year.  The toy retailer says the decline is because it has implemented new policies that will allow seasonal staffers to take on more hours than they were able to in the past.

The composition of retailers’ holiday workforce is changing as more shopping moves online.  Instead of cashiers and greeters, many stores are in greater of need of workers who can pack and process online orders. Of the 60,000 seasonal workers being added by Wal-Mart, the country’s largest retailer, 3,500 will be department managers who will manage orders that have been placed online for in-store pick-up.

Frank Layo, a retail supply chain strategist at consultancy Kurt Salmon, said some retailers looking to fill warehouse and e-commerce jobs this year could find themselves facing a labor shortage.   As the job market has improved, he said, there might be fewer people willing to take these physically taxing jobs.  And many retailers will have even more of these kinds of positions to fill than they have in the past.

Layo said many of his clients are already struggling to get enough warehouse workers as they bring in holiday goods. 

“It’s not a dramatic impact on their bottom line right now, but it is the early warning sign it’s going to be a bigger problem,” Layo said.

Sally Lynch, vice president of national accounts at employment agency Staffmark, said she and her team are already finding it more challenging to fill seasonal warehouse jobs.

For a client with 100 openings, Lynch said, “to get those 100, you have to do a lot more aggressive recruiting and cast a wider net. Whereas three years ago, you could post on a job board and just by that activity, fill those positions.”

Major shippers UPS and FedEx have also begun their holiday hiring blitz.  UPS estimates it will hire up to 95,000 workers, slightly less than the 100,000 it added last year.  FedEx plans to add 55,000 temporary employees, about 5,000 more than last year.  E-commerce giant Amazon.com has yet to announce how many workers it will be looking to bring on.