Traders piled in to buy cocoa options this week as futures surged to record highs on concern global supplies will be tight after drought and disease ravaged crops in top West African producers.

Implied volatility — a key measure of options costs — doubled since mid-January, with an especially high premium being paid for calls protecting against higher prices over the next couple of months. Soaring raw-material costs already are weighing on chocolate makers and may force Hershey Co. to raise prices, the company’s CEO said Thursday.