Written by Emma Stafki
Photo courtesy of NOAA
Introduction
Added to the list of threatened species in 2005, the Southern Resident Orca (Orcinus orca) population has continued to decline. Orcas are highly social and live in family groups called pods. Currently, the Southern Resident Orcas consist of three pods the J-, K-, and L-pods. They reside in the Strait of Georgia (British Columbia), the strait of Juan de Fuca (between Canada and the United States), and Puget Sound (Washington State). Since 1974, annual photo-identification research has been conducted and has documented the considerable population fluctuation in the Southern Resident Orcas. 1974 counted 71 Orcas, 1996 counted 97, and a “steep decline of 20% occurred between 1996 and 2001 (from 97 whales to 78)” (Krahn). Three serious threats to the Southern Resident Orcas have been identified. These threats include contaminants/persistent organic pollutants, limited availability to their prey Chinook Salmon and physical and acoustic noise disturbance.
Persistent Organic Pollutants
The Southern Resident Orcas have been found to have higher than normal persistent organic pollutants in their blubber leading to possible health issues. Persistent organic pollutants or POPs include “both chlorinated [e.g., PCBs, DDTs, chlordanes, hexachlorocyclohexanes (HCHs) and hexachlorobenzene (HCB)] and brominated [e.g., polybrominated diphenyl ethers (PBDEs)] environmental contaminants” (Krahn) and much evidence links these contaminants to biological effects including increased chance of infection, immune, reproductive and endocrine system dysfunction. Embedded into the tissue of marine predators by the prey they feed on are chemical “tracers”. These tracers can help to provide diet information important in learning about the pollutants affecting Orca populations. By measuring the stable isotope values of nitrogen and carbon, the geographic area of the Orca can be assessed. By understanding patterns and ratios of POPs, one can gain insight into the location of pollutants transferred from prey to predator (Krahn). POPs are gained over the lifetime of each Orca. When a mother gives birth the POPs are transferred to the offspring, so it was found that younger Orcas and males had the highest levels of POPs. An orca can also receive POPs from the prey they eat, therefore the toxins found in Chinook salmon would be passed to the Orca that eats them. Learning where the POPs are coming from geographically can be helpful in understanding the dangers facing southern resident orcas and give insight on how to correct the problem.
Limited availability to their prey Chinook Salmon
There is a strong correlation between the decrease in the population of the southern resident orcas in the mid-nineties to the decrease in the chinook population which is their primary food source. As Chinook Salmon become increasingly scarce, the orcas are forced to rely on their blubber as an energy source during times of food shortage. Unfortunately, this survival mechanism comes with a deadly consequence: the release of persistent organic pollutants (POPs) stored in the blubber into their bloodstream. These toxins, which include harmful chemicals like PCBs and DDTs, can cause severe health issues, weakening the orcas’
immune systems, impairing reproduction, and leading to a host of other physiological problems. Throughout the region of the Pacific Northwest, “40 percent of chinook runs already are locally extinct, and a large proportion of the rest that remain are threatened or endangered. Meanwhile, most other marine mammals are surging in population, adding to the competition both southern residents and fishermen face” (Mapes). This competition for dwindling resources places additional strain on the Southern Resident Orcas, who are already battling the effects of pollution and habitat loss. If the issue of Chinook Salmon depletion isn’t addressed, the Southern Resident Orcas face an uncertain future. Their survival is intricately linked to the availability of this vital prey, and without significant efforts to restore Chinook populations, the southern resident orcas will continue to struggle in an environment that is becoming increasingly hostile. The cascading effects of this crisis not only threaten the Southern Resident Orcas but also jeopardize the entire marine ecosystem, highlighting the urgent need for comprehensive conservation measures to protect both the orcas and their essential food source.
Sound Pollution
Sound pollution is devastating for Orcas because they rely on sound for communication. “Sound is critical to all of the orcas’ essential life functions, from sticking together in a dark ocean, to finding mates, and hunting fish” (Seattle Times, Holt). With a sea providing fewer
Photo Courtesy of NOAA
and fewer chinook it is imperative that excessive sound pollution comes to an end. Orcas use “so-called echolocation clicks” which are bursts of sound that come through fat in a reservoir called the melon located at the front of the head. A different fat-filled reservoir located in the lower jaw communicates to the middle ear, the inner ear, and finally, the hearing centers on the brain when an echo from the clicks bounces back. Noise pollution has been making it increasingly difficult for Orcas to communicate and locate their prey, adding to the many difficulties they face on a daily basis.
The Southern Resident Orca Task Force
In 2018, Governor Jay Inslee of Washington State established the Southern Resident Orca Task Force in order to identify ways that the state could protect the orcas. Washington State is also working to “improve fish passage for salmon, developing rules for commercial viewing of Southern Resident killer whales, and partnering with fellow state agencies to support an update of the Governor’s Office’s 20-year plan for salmon recovery” (WDFW). Despite the state's help in protecting orcas, so much more could be done. A letter explaining what WDFW wants to accomplish in the future states the following; First, they want to continue implementing the Southern Resident Killer Whale Task Force’s recommendations. Second, they want to continue partnering with Canada to keep tabs on/reduce shipping impacts. Third, work with the U.S. Navy to reduce disturbance and noise impacts during training activities. Fourth, support Chinook salmon recovery by preserving and restoring habitat. Fifth, continue to support the protection of natural resources and the environment. All of these actions need to be prioritized in order to protect the Southern Resident Orcas. Some pros of these actions include the possible rise in Orca and Chinook populations, and furthermore, all of these actions would be helpful to all marine organisms. Some cons would include cost and the difficulty that comes with monitoring shipping impacts and noise disturbance.
What can you do?
The state must make changes to protect the Orcas and there are also everyday changes anyone can make to support the orcas. Firstly, you can use your voice by reaching out to officials and encouraging them to oppose harmful changes to the Marine Mammal Protection Act and the Endangered Species Act. Second, you can make small changes in your household to reduce the number of pollutants and containments that enter the water by switching to all-natural cleaning and beauty products. Look for ones that don’t contain microplastics and other harmful chemicals. Third, bring your car to a self serve or tunnel carwash to keep soap out of storm drains. Fourth, reduce your plastic consumption by using reusable food storage bags, grocery bags, mesh produce bags, and reusable water bottles. Fifth, choose your fish wisely. Chinook salmon is the main food source for Southern Resident Orcas so when picking out your next meal try for fish other than Chinook. Sixth chose responsible whale watching companies. If you are booking a trip ask about the company's commitment to the viewing guidelines. Seventh, make sure you understand the viewing laws for whale watching if you are taking your own boat out looking for the orcas. Eighth, support local organizations that are working to protect the Southern Resident Orcas such as the Whale Museum based in Friday Harbor. Ninth, take part in roadway and beach cleanups to keep the Puget Sound trash free. Tenth, share the story of the Southern Resident Orcas. Our chances of saving the Orcas increase when more people demand action. (San Juan Island Visitors Bureau).
Photo Courtesy of NOAA
Conclusion
Orcas are sentient beings who live together, take care of each other, and love each other. We (humans) are the reason that the southern resident orca population is declining and it is up to us to right our wrongs. As a society, it is our responsibility to protect our environment so that creatures in our world have the ability to live and thrive in their home waters again.
References
Campbelle, J., & . (2019, November 25). Top 3 reasons open net-pen salmon farms threaten wild salmon. Watershed Watch Salmon Society. Retrieved June 6, 2022, from https://watershedwatch.ca/top-3-reasons-open-net-pen-salmon-farms-threaten-wild-salmon/
Holt, M., & Mapes, L. (2019). The Roar below: How our noise is hurting orcas' search for Salmon. The Seattle Times. Retrieved June 2, 2022, from https://projects.seattletimes.com/2019/hostile-waters-orcas-noise/
Krahn, Bradley Hanson, M., Schorr, G. S., Emmons, C. K., Burrows, D. G., Bolton, J. L., Baird, R. W., & Ylitalo, G. M. (2009). Effects of age, sex and reproductive status on persistent organic pollutant concentrations in “Southern Resident” killer whales. Marine Pollution Bulletin, 58(10), 1522–1529. https://doi.org/10.1016/j.marpolbul.2009.05.014
Mapes, L. V. (2020, June 26). Hunger: The decline of salmon adds to the struggle of Puget Sound's Orcas. The Seattle Times. Retrieved June 2, 2022, from https://www.seattletimes.com/seattle-news/environment/hunger-the-decline-of-salmon-adds-to-the-struggle-of-puget-sounds-orcas/
San Juan Island Visitors Bureau. (n.d.). How you can help southern resident orcas. visitsanjuans.com. Retrieved June 2, 2022, from https://www.visitsanjuans.com/how-you-can-help-southern-resident-orcas
WDFW. (2020, October 30). How Washington is doing on Orca Recovery - and what comes next. Medium. Retrieved June 2, 2022, from https://watershedwatch.ca/top-3-reasons-open-net-pen-salmon-farms-threaten-wild-salmon/
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