(ShareCast News) - Nighthawk says its total 3P reserves rose to 3.89m barrels at 31 December, 2016, from 3.64m barrels a year earlier.Total proved reserves rose to 1.54m barrels, from 1.41 barrels. Probable reserves rose to 1.8m barrels, from 1.42m barrels, while possible reserves fell to 545,000 barrels, from 807,000."The increase in probable reserves ... is primarily due to improved response estimates and reclassification of reserves from the possible reserves classification due to the commencement of the water flood pilot project," the company said."The increase from prior year total proved reserves is due to reserves associated with proved undeveloped category which were deemed uneconomic at 2015 year-end pricing," it said.At about 10:20 GMT, shares in AIM-listed Nighthawk were flat at 1.28p