Most actively traded companies on the TSX

Some of the most active companies traded Monday on the Toronto Stock Exchange:

Toronto Stock Exchange (14,862.76, up 131.26 points):

Pacific Rubiales Energy Corp. (TSX:PRE). Oil and gas. Down 40 cents, or 12.94 per cent, to $2.69 on 6.5million shares.

Rio Alto Mining Ltd. (TSX:RIO). Miner. Down 27 cents, or 7.94 per cent, to $3.13 on 5.8 million shares.

Bombardier Inc. (TSX:BBD.B). Transportation. Unchanged at $2.49 on 4.6 million shares.

Canadian Oil Sands Ltd. (TSX:COS). Down 61 cents, or 6.43 per cent, to $8.87 on 4.6 million shares.

Encana Corp. (TSX:ECA). Oil and gas. Up 23 cents, or 1.67 per cent, to $14.01 on 4.5 million shares.

Mart Resources, Inc. (TSX:MMT). Oil and gas. Up two cents, or 3.57 per cent to 58 cents on 3.7 million shares.

Companies reporting major news:

Ensign Energy Services Inc. (TSX:ESI). Oil and gas. Down 16 cents, or 1.72 per cent, to $9.16 on 860,386 shares. The company posted a quarterly net loss of $31 million or 20 cents a share as it recognized $89.5 million in non-cash charges for decommissioning and writing down assets — primarily oil and gas drilling rigs.