As of early Wednesday, hunters had culled about 410 narwhals trapped in sea ice near Bylot Island, about 17 kilometres from the Baffin Island community of Pond Inlet, Nunavut. (CBC)

The federal Department of Fisheries and Oceans says there were hundreds more narwhals trapped in sea ice near Pond Inlet, Nunavut, than originally thought.

Department officials told CBC News that as of Wednesday morning, about 410 narwhals had been hunted from the ice near the remote Baffin Island community over the past five days.

When the trapped narwhals were first discovered on Nov. 15, residents had counted at least 200 of the Arctic whales, trapped in shrinking areas of open water, also known as breathing holes or savssats.

But since the first discovery, fisheries officials say more breathing holes have been spotted. The department now estimates a total of 500 narwhals were trapped in as many as 20 breathing holes.

'Overwhelming' task of culling whales: hunter

Department official Keith Pelley told CBC News that an officer is in Pond Inlet to ensure each hunted narwhal is tagged, in order to track numbers.

"We are actually evaluating the situation," Pelley said Wednesday.

"I mean, there's nothing you can do about a natural occurrence, but I will have to evaluate this for future decisions in relationship to this [narwhal] stock."

Hunters in Pond Inlet, a mostly Inuit community of about 1,300, told CBC News that the task of culling hundreds of entrapped whales has been daunting.

They added that they are trying to harvest as many whales as they can with the limited amount of daylight they have at this time of year.

"Yeah, it's been overwhelming," Brian Koonoo, a member of the Mittimatalik hunters and trappers organization in Pond Inlet, said Wednesday.

"At first we didn't know how many there were, since some of them were under water," he added. "But right now they are trying to deal with them and Pond Inlet is doing their best and they're working really hard."

DFO officials are agreeing with local elders who have advised hunters to kill all the narwhals soon, or else the trapped whales would die of starvation and a lack of oxygen as the ice closes in around them.

Pelley commended the hunters for conducting a well-organized harvest that has prevented the trapped narwhals from suffering. The hunt will continue until all the whales are killed.

The trapped whales are believed to be from the Eclipse Sound narwhal population, which DFO estimates has a population of about 21,000.

While that population is considered to be healthy, Pelley said his department and Nunavut wildlife officials will review the Pond Inlet situation after the cull is done.