Fresh news in the killer whale world, Surprise! (L-86) just gave birth! Since July 2020, three different Southern Resident Killer whales have given birth! J35, Tahlequah, who lost her baby about two years ago, gave birth on September 6th, 2020, to a baby boy, J57. Next, J41, Eclipse, was the second mom, giving birth to her offspring on September 25th. And now L-86, Surprise, gave birth to her baby. This fantastic news raises spirits, considering the Southern Resident killer whale population is extremely endangered, with little to no growth in years. This threatened population has been on the decline since 2015, with now 75 animals in total and every killer whale baby counts! Now you must be wondering why this is happening? Why there are there new babies now? Well, we have a few hypotheses that might help explain this amazing event.
Low survival in killer whale babies
Firstly, according to Dr. Holly Fernbach, a marine mammal health researcher, there are often pregnant females. Yet, 69% of pregnant southern resident whales lose their babies before birth or soon after. Scientists estimate that between 37% and 50% of calves don’t survive their first year. It is not too uncommon for a first-time whale mom to lose their calves. But given the crucial need for this population to recover, babies’ low survival rate is a concern.
Killer whale females reach sexual maturity at the age of 12, and they go through menopause around 40. They have a long gestation period of about 18 months. Due to the low success with birth rates, scientists typically do not advertise killer whale pregnancies. However, things are different now as scientists hope this series of announcements could enforce whale disturbance restrictions. It would allow the Southern Residents to have more space and quiet.
A quieter ocean due to COVID-19?
Heavy vessel traffic in the whales’ habitat translates to more time traveling and less time foraging for the whales. It interrupts echolocation clicks the whales use to hunt salmon. The speed of vessels is the most significant factor in determining how much noise is produced, more so than the ship’s size.
Last year, 2019, Governor Jay Inslee (Washington State, USA) ratified a new regulation regarding the Southern Residents. The new rule requires vessels and boaters to stay at least 300 yards away while maintaining at least 400 yards from their path or behind the whales. The regulation also requires vessels to reduce their speed to seven knots within a half-mile of the orcas. The Pacific Whale Watch Association developed science-based guidelines as well. Boaters should watch for the Whale Warning Flag, an optional tool developed by the San Juan county to help boaters know and become aware of potential killer whales in the area.
With these measures implemented, scientists and local communities hope for a less stressed and more successful Southern Resident. That way, the orcas get more time to look for food. And with a quieter ocean during the COVID-19 pandemic and lockdown, finding food must have been easier for the Southern Residents. Whale watching and tourism also came to a halt, giving the whales enough privacy to enjoy their pregnancies fully.
Enough food to survive and feed a baby
Killer whale cows need enough food before, during, and after a successful pregnancy. They need a lot of energy to give birth and feed their calves. Killer whales will take two to three years to wean a calf (introduce a baby to its adult diet) gradually. The calf is entirely dependent on its mother up until then. One can only imagine how much extra fish these moms require.
This need for extra food and energy is highly stressful and taxing on the mom. Yet, killer whales are highly social and dependent on their communities, helping other family members. With limited food supplies, the killer whale pod ensures all members get as much food as possible. Pods also include an excellent support team of aunties, sisters, and mothers to support new moms.
Lactation and weaning require the most work for new orca moms. Their caloric needs skyrocket after birth, as they provide 40% fat milk to help their babies grow rapidly. According to Dr. Hendrik Nollens of NOAA, “If a killer whale has unlimited access to food, the food intake within days will go up 50%.” But this ideal scenario is far from the reality of the Southern Residents. The resident killer whales’ primary food source is chinook salmon that makes up about 80% of their diet. The bad news is: chinook salmon is also an endangered species. This results in orca moms struggling to feed themselves, let alone have enough energy to provide for their offspring. Weaning also lasts longer due to the lack of fish needed to supplement their nutrition.
Needless to say, we need to find a way to restore the chinook salmon populations to make sure the whales have enough food. Dr. Deborah Giles stated, “In my opinion, to save these whales, we have to be laser-focused on the food issue, and then secondarily the toxicants issue”. Chemical contamination is also a concern…
Contamination, the silent killer
Contaminants include a wide range of chemicals like heavy metals, industrial chemicals, pesticides, flame retardants, oil additives, etc. A group of contaminants known as persistent organic pollutants (POPs) comprises long-banned human-made substances that do not degrade in the environment. They include the infamous PCBs (polychlorinated biphenyls) known to cause hormonal imbalance, reproductive issues (like a miscarriage), immune failure, and even cancer!
These chemicals are lipophilic, which means they bind to fat. Killer whale moms transfer a lot of their fat to their babies, mainly through 40% fat milk. Scientists believe up to 60% of their contaminant load is transferred to the baby this way. The worst part is: the first pregnancy offload the most chemicals. Newborns do not have high survival chances because they receive so many chemicals that their bodies cannot process. It just ends up slowly killing them. A baby orca found dead on the shore in Germany last year had crazy contaminant levels in its body, and they likely had something to do with its death. As a result of chemical contamination, half of the world’s killer whale populations could disappear before 2100. This means that governments should keep making efforts on contaminant management and clean-ups.
If a killer whale mother has a miscarriage or stillbirth because of contaminants, she will have more chances to succeed in their next pregnancy if it comes quickly after the miscarriage. It sounds traumatic, but this way, she will transfer fewer contaminants to her baby. This could have happened to J35, Tahlequah.
Giving birth to a killer whale baby is no picnic…
Late-term calves can act like ticking time bombs in their mothers’ bodies. Calves can get caught in the birthing canal. If they aren’t released quickly, then they can cause a bacterial infection for their mothers. Calves that do make it through the birth canal need to swim to the surface and take their first breath immediately. It takes about 1-2 hours to come out entirely, and when they come out tail first, they have time to acclimate to their new environment. Their flukes are not fully functional, nor do they have control over it yet, so they need a lot of assistance reaching the surface for a while.
Finally, male orcas can be a serious threat to newborns and their mothers. Often, they can become aroused during childbirth. They then act aggressively toward the calf if females don’t keep them away. Dr. Nollens has heard reports of rake marked newborns think it’s likely from males trying to get to their moms.
With this many stressors, it is a miracle three babies were born in the fall of 2020. The COVID-19 pandemic might have helped pregnant mothers by allowing them to search for food in a quieter environment. We hope the three calves grow healthily and become strong adult orcas. And we need to remember: every killer whale baby counts towards the recovery of the Southern Residents.
Thank you for reading! Please check out our other posts on killer whales:
For additional readings on the topic:
- Here’s what pregnant orcas are up against in Puget Sound
- NOAA: Give Pregnant Killer Whales Space to Forage
- SR3: SeaLife Rescue, Response, Research