(ShareCast News) - Shares in Caza Oil & Gas plunged almost 8% on Thursday, after the explorer said its pre-tax loss widened in the second quarter due to a decline in production.In the second three months of 2015, the London-listed group saw its pre-tax loss widen from $0.76m to $3.3m, while revenue more than halved to $2.9m as lower production levels and a slump in oil and gas prices hit the firm hard.The group's net loss in the first half more than doubled to $4.6m, while revenue plunged 42.2% to $6.3m.The average oil price in the quarter plummeted 46% to $50.36 per barrel, while gas prices fell 33% year-on-year to $2.99 per million standard cubic feet.However, while oil prices were marginally higher from the previous three months, gas prices edged 2.6% lower quarter-on-quarter.Caza said its oil and natural gas liquid production declined 20% quarter-on-quarter to 58,847 barrels, which represented an 11% decline year-on-year.As a result, the average net production volumes stood at 744 barrels of oil equivalent per day, an 18% drop from the previous quarter and a 21% slump from the corresponding period in 2014.The group said despite the current pricing environment and the inevitable impact on both revenues and production, it was confident of meeting its targets and expected commodities prices to improve in the short-term future.Caza added it aims to expand its drilling programme in the Bone Spring play within the next two years.Caza shares were down 7.69% to 1.50p at 1109 BST on Thursday.