Around May 24, 2019, a baby girl was born.

But she is not just any baby girl. The infant is the latest addition to the Southern Resident killer whale (SRKW) population – a community made up of just 76 killer whales (or orcas).

Her arrival is particularly good news because births have been sparse and overwhelmingly male in recent years, a situation that could be more than a little problematic from a reproductive point of view further down the line.

The birth was confirmed on July 6, 2019, by researchers at the Center for Whale Research (CWR) in a press release, a day after J and K pods of the SRKW population returned to the inland waters off San Juan Island, Washington, following an absence of more than two months. The news had previously been reported by a local whale watch company on May 30, who spotted the calf near Tofino on the British Columbia coast. It meant that by the time of their return, there was already a crowd of people gathered there to greet them.

The mother (imaginatively named J31) was seen swimming around in circles, calf in tow, alongside three other young females. At one point, the calf (now called J56) appeared at the surface, exposing her belly and revealing she was female.

The CWR calls her "a very welcome addition" to a population that has experienced a lot of bad news recently. The already endangered community of orcas (made up of three social groups, or pods – J, K, and L) has been weakened, with individual whales appearing skinny and passing away. 

What's more, as IFLScience reported in July 2018, scientists have been unable to record a single calf for three years, a situation resulting in the lowest numbers of SRKW population killer whales for 30 years. (Nine calves had been born in 2015 in a "baby boom".) When one was eventually spotted, later that month, the calf was already dead – you may even remember the heartbreaking story of a grieving mother orca (J35) who carried her deceased calf for 17 days and 1,610 kilometers (1,000 miles). 

Part of the problem is that orcas give birth to just one calf at a time and this only happens once every three to 10 years after a female turns 14 or 15. While female orcas live, on average, 50 years and some can possibly reach centenarian status (males have a shorter lifespan), they hit something akin to menopause and stop reproducing at around 40 years of age. The gestation period lasts 16 to 17 months and a little over half of the calves survive to their first birthday. In the last 20 years, that percentage has risen to roughly 75 percent. All this means that most females have between four and six surviving offspring during their lifetime.

J31, a 24-year-old whale, has had no known pregnancies in the last decade, with her most recent birthing (January 2016) sadly proving unsuccessful.

But also to blame are the predominantly human-driven factors threatening the SRKW population, namely pollution, noise from shipping vessels, and shortages in their preferred food supply (king salmon), which has fallen so drastically that orcas have turned to feeding in coastal waters to make it through the summer, CNN reports.