A newborn calf in a southern resident killer whale pod has been spotted in the waters around Tofino, British Columbia.

Department of Fisheries and Oceans marine mammal co-ordinator Paul Cottrell called the birth wonderful news.

He says the southern resident killer whales are currently an endangered population, numbering just 75, so any births are significant.

He says the first year is tough for killer whales babies, with a 50 per cent mortality rate, but another calf born in January still appears to be doing well.

The first calf born in three years to the endangered orcas died shortly after birth last August and its mother pushed the baby's body through the water for weeks.

Scientists from the National Oceanic and Atmospheric Administration in the United States released photos last week showing a female adult Southern resident and her 3 1/2-year-old calf in declining in health.