The Department of Fisheries and Oceans is considering licensing the recreational cod fishery in Newfoundland and Labrador, after officials discovered the amount of fish caught could be four times what it estimated.

CBC News obtained documents under the Access to Information Act that show two different sets of numbers collected by DFO for the 2007 recreational fishery, or food fishery.

The 2007 food fishery allowed anyone to catch as many as five fish per day, with a boatload limit of 15 when more than three people are on a vessel.

The first set of numbers DFO collected was during the three-week food fishery by fisheries observers who spent time on the water, talking to people and collecting information. The observers then compiled the information and estimated that 542 tonnes of cod fish were taken in the recreational fishery.

Suvery shows increased numbers

The second set of numbers were also collected by DFO, by telephone survey, after the food fishery.

Wanting to double check its own numbers, the documents show DFO hired a consultant to conduct a survey of about 1,100 people, to see how many fish they reported catching.

The consultant concluded that 2,400 tonnes of cod were taken, and that more boats and people were on the water than DFO had thought.

Internal DFO memos, also obtained by CBC News, show staff at the department were concerned with the discrepancy in the two sets of numbers. One memo suggests that people exaggerated their catches when doing the phone survey.

One official wrote: "The telephone survey appears to be a significant overestimate of the .. . cod catch. [It] is inconsistent with the observed activity ... inconsistent with the cod tagging data, significantly overstates the average fish size and makes no attempt to investigate non-reponse bias."

Officials at Statistics Canada reviewed the survey and found it was was statistically valid and conducted properly.

The Fisheries Department is now considering a licensing program for each regional food fishery in the province, that would see people register for the fishery and report the exact number of fish they catch.

Meanwhile, federal Fisheries Minister Loyola Hearn said Wednesday that he's not concerned about the numbers the telephone survey returned, and the fact that his department is looking at introducing a licensing program has nothing to do with the survey results.

Hearn said the method of licensing would be similar to the recreational salmon fishery.

He said any fees would be just enough to cover the cost of printing the licence, and not so much as to deter people from getting a licence.

"You go to the corner store and pick up your card for a small fee and then keep a record," Hearn said. "And everyone wins at the end of the year."

Hearn said his department is looking into the licence, to keep a better track of how many fish are taken during the receational fishery.

If the licensing plan is approved, it could be in place by 2010.