But the study, which claims Chinese vessels catch about 12 times more than is reported to the United Nation's Food and Agriculture Organization, immediately received criticism from the UN.
Dirk Zeller, co-author of the report published in the latest edition of the journal Fish and Fisheries, said his research indicates about 4.6 million tonnes of fish is taken by China from the waters of other countries, around 3.1 million tonnes of which are from West African waters alone.
He said it's worrisome because if countries aren't properly reporting catches, there is no way conservation plans can be made to maintain stocks of fish.
"The uncertainty range around (the number of tonnes of fish) is about from 3.5 million to a bit over 6 million. So actually it's quite a range around what it could be," said Zeller.
From his research, which involved a team of 20 researchers working for almost eight months, Zeller is certain that at least several million tonnes of fish go unreported by China each year.
Richard Grainger, chief of statistics for the UN Food and Agriculture Organization, disagrees.
Grainger said the figures in the UBC paper seem wrong because the estimate of 3.1 million tonnes of fish taken from West Africa by China is close to equalling the total catches West Africa produces annually on its own.
He said a 2009 estimate from the University of California that up to 560,000 tonnes of unreported fish are taken from West African waters is a far more accurate number than the 3.1 million in the UBC study.
"We ... believe that the estimates in this paper of Chinese catches off West Africa are far too high," said Grainger in an e-mail statement.
Zeller said his research team gathered data by reviewing fishery "footprints," such as scientific reports and media reports, to get the estimated number.
The team also looked at the types of vessels used in China and the vessels' catch capacities.
Zeller acknowledges that the UN is in a difficult position to criticize China because its such a powerful player in the organization economically and politically.
"(The UN) doesn't have a mandate to collect data. It is required to report data that countries provide," he said.
"China is such a powerful player in the UN ... that China can basically tell (the UN Food and Agricultural Organization) to mind its own business and it doesn't have to or feel compelled to accurately, or as accurately as possible, report on its data."
Zeller said his project is ongoing because he knows most countries aren't reporting everything that's fished.
He wants to eventually estimate the true catch rate for every country in the world.
"We have to be aware the Chinese are a major player in global fisheries. They have probably the largest border fishing fleet in the world and they've indicated they're trying to expand it," he said.
"They are extremely secretive about their fisheries and therefore about the information they release about it. And that's a problem for accountability ... They are not necessarily alone on this, but given the magnitude of their fisheries that is, of course, a huge problem globally."
Also on HuffPost