By David Russell, reporter at OptionMonsterNEW YORK -- The energy trade has been a constant drumbeat for months, and Tuesday the bulls turned to Encana ( ECA). OptionMonster's tracking systems detected heavy buying in the February 19 calls, initially for 45 cents to 50 cents. The Canadian natural-gas stock was trying to hold support at $19 when the trades hit, but then it started to climb. Calls lock in the price where investors can buy shares, so they can generate some nice leverage in the event of a rally. That's what happened as the stock pushed higher because those options would trade for 80 cents later in the session. Some 12,600 contracts changed hands against previous open interest of just 709 in the strike at the beginning of the day, clearly indicating new activity. Encana's shares finished the day up 2.1% to $19.47. The stock had been holding key support above $19 for more than a month. Total option volume in the name was almost eight times greater than average in the session. While there was also heavy put activity, most of those contracts were sold. That's also bullish because it reflects a belief that there is little downside risk. Russell has no positions in ECA.