By Svea Herbst-Bayliss

BOSTON (Reuters) - Wealthy investors protested the hedge fund industry's recent lackluster returns and high fees by pulling a net $4 billion out of the $2.5 trillion industry during the first two months of 2015, data released on Tuesday show.

The number contrasts with the heady days of 2014 when investors added $31.6 billion of new money in January and February, research firms BarclayHedge and TrimTabs Investment Research said.

Hedge funds have long been popular choices with big-name investors like pension funds and endowments, but last year's roughly 3.3 percent return, which lagged the Standard & Poor's 12 percent climb, plus giant pension fund Calpers' decision to exit all hedge funds has prompted some investors to rethink, industry analysts have said.

Longer-term data shows the slowdown in demand even more starkly, said Sol Waksman, president and founder of BarclayHedge. "In the past 12 months, hedge funds added $39.2 billion, down 57 percent from $91.4 billion in the previous 12-month span," he said.

In February, the data shows a slight improvement with hedge funds taking in $7.2 billion in new money, marking the strongest inflows in the past six months. But the rebound was eclipsed by January's $11.2 billion in outflows, the researchers said.

Some of the flows may have been linked to improved returns with the average hedge fund earning a 2.2 percent gain in February, the best returns in two years. But the broader stock market fared even better with the S&P 500 gaining 5.5 percent.

(Reporting by Svea Herbst-Bayliss; Editing by Leslie Adler)