Whale researchers say it's "unprecedented" that endangered southern resident killer whales normally found in the Salish Sea this time of year are nowhere to be seen.

The 75 remaining orcas, split between J, K and L pods, are usually feeding on chinook salmon in the Salish Sea by July, according to Wild Orca science and research director Deborah Giles.

But so far this summer, the whales haven't been seen in the area at all, something Giles called unprecedented in the time researchers have been monitoring them.

There was an unconfirmed report of southern residents on the west coast of Vancouver Island on June 27, but Giles said scientists have not confirmed the sighting.

She said it's important endangered orcas gather in the Salish Sea because it's healthier for the population when breeding.

Dwindling chinook salmon populations may be to blame for the species' no-show status in the Salish Sea, according to Giles.

In April, Fisheries and Oceans Canada introduced tough new restrictions on chinook fishing in B.C. waters, closing recreational and commercial fishing areas in the Strait of Juan de Fuca and the Gulf Islands.

It's not all bad news for the endangered orcas. J-pod was spotted near Tofino in May with a new calf in tow, and researchers said they were "cautiously optimistic" about the calf's chances of survival.

With files from CTV Vancouver Island's Brad MacLeod