WRAPUP 1-E&P cos results hit as oil and gas prices, sales fall

* Continental Resources, Swift Energy swing to Q1 loss

* Profits at Pioneer, Plains drop more than 90 pct

* Weak oil, gas prices hurt results at Continental, Swift

* Swift shares rise 16 pct

By Adveith Nair and Arup Roychoudhury

BANGALORE, May 7 (Reuters) - A group of oil and gas explorers and producers reported first-quarter results that were hurt by a sharp dip in oil and gas prices, and declining sales.

While Continental Resources Inc (CLR.N: Quote, Profile, Research) and Swift Energy Co (SFY.N: Quote, Profile, Research) swung to a first-quarter loss, Pioneer Drilling Co (PDC.A: Quote, Profile, Research) and Plains Exploration & Production Co (PXP.N: Quote, Profile, Research) reported a sharp dip in quarterly profits.

Continental Resources and Swift Energy were hurt as U.S. natural gas prices NGc1 more than halved from their July 2008 highs and crude prices CLc1 dropped more than $100 a barrel from an all-time high of $147.27 in the same period. [ID:nBNG32424] [ID:nWNAB5205]

Continental Resources' average sales price per barrel of oil equivalent (boe) dropped 63 percent to $29.90 for the first quarter, while average price per boe at Swift Energy dropped 58 percent to $32.29 during the quarter.