Biology:Southern resident killer whales

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The research vessel Noctiluca of the Northwest Fisheries Science Center in close proximity to an orca

The southern resident killer whales (SRKW) are the smallest of four separate, non-interbreeding communities of the exclusively fish-eating ecotype of orca in the northeast portion of the North Pacific Ocean. The fish-eating ecotype was historically given the name 'resident,' but other ecotypes are also resident in the area. The National Marine Fisheries Service listed this distinct population segment of orca as endangered, effective in 2005, under the Endangered Species Act.[1] In Canada the SRKW are listed as endangered on Species at Risk Act Schedule 1.[2] They are commonly referred to as the "orcas of the Salish Sea",[3] "fish-eating orcas", "southern residents", or the "SRKW population". Unlike other resident communities, the SRKW is only one clan (J) that consists of 3 pods (J, K, L) with several matrilines within each pod.[4] As of July 2021 there are only 74 individuals.[5] The world's oldest known orca, Granny or J2, had belonged to and led the J pod of the SRKW population. As of October 2016, she is missing and presumed deceased.[6] J2 was estimated to have been born around 1911, which means she would have been 105 years old at the time of her death, and the oldest known orca to date.[7] On July 24, 2018, the first calf born in three years died after being alive for only half an hour.[8]

Social structure

Photo identification over the last 38 years has allowed researchers to track the southern resident population quite accurately, such as the Orca ID site[9] offered through the Center for Whale Research. Their population is built upon a matrilineal system where these strong hierarchical groups of individuals are connected by maternal descent. Each matriline consists of a female, her sons and daughters and the offspring of her daughters; averaging anywhere from one to seventeen individuals and one to five generations within each of these matrilines.[4] Pods are groups of matrilines that share a maternal ancestor, in which the southern residents consist of three pods. The number of individuals changes due to birth and deaths.

The Orca Network provides a list (last updated March 2 2022). The following is the basic social structure:[10]

Community
Southern Resident
Clan
J
Pods
J Pod (25 members)
K Pod (16 members)
L Pod (33 members)
Matrilines
J2 (believed deceased as of October 2016), J4, J5, J7, J10, J11, J32 (found dead on a beach on Vancouver Island on December 4, 2014.)
K4, K7, K8, K11, K18 (last member, K21 Cappuccino, last seen July 29, 2021 at the age of 35)
L2, L4, L9, L12, L21, L25, L26, L28, L35, L37

In 2014, L120 was born into L pod but didn't survive more than a month. In late 2014, J50 Scarlet was born into the J pod. After a lot of speculation, J16 Slick was confirmed to be J50's mother, making the 42-year-old the oldest ever recorded orca mother. The gender of the calf is confirmed to be female.[11]

In February 2015, two new calves were spotted, a male calf in J pod, designated J51 Nova, and another male in L pod, designated L121 Windsong. J51's mother is ten-year-old J41 Eclipse and L121's mother is twenty-year-old L94 Calypso. A fourth calf, designated J52 was born in March 2015 to J36 Alki, who is J16's daughter. In early 2016, J52 Sonic was confirmed to be male, however he died in September 2017, presumably from starvation.[12] Since 1998, 40 orca calves have been born to J, K & L pods and survived, while 72 orcas have gone missing (presumed dead) or have been confirmed dead.[13]

In August 2018, the pod attracted international attention after the death of a female calf born to J35 Tahlequah and the sickness and death of another calf, J50.[14]

In January 2019, L124 Whistle was born to L77 Matia and is her third calf. In May 2019, J56 Tofino was born to J31 Tsuchi as her first calf and her gender was later confirmed as female.[15]

In September 2020, J57 Phoenix was first seen traveling with J35 Tahlequah and is her second calf. His gender was determined as male a short time later.[16] On September 24, 2020, J58 Crescent's birth was observed and she was confirmed as the second calf of J41 Eclipse by the Center for Whale Research the next day. Her gender was later confirmed as female by the Center for Whale Research. [17]

In 2021, there was only one birth, L125 Element to L86 Surprise!, her fourth calf, born around February.[18] Her gender was confirmed by Department of Fisheries and Oceans Canada (DFO) later that year. [19]

In February of 2022, a new calf was seen with J37 Hy'Shqa, her second calf, and was given the alphanumeric designation of J59. The calf's gender was revealed to be female on May 29, 2022. [20]

Dialect

Similar dialects amongst pods create the social grouping called "clans". It is believed that the more similar their dialect is within the pods, the more closely related they are. The southern dialect is very different from that of other communities. For instance, northern residents use whistles as their main type of close-range communication and the southern residents use whistles for regular social interactions and long-range communications. Southern residents appear to be much more vocal but it could be due to their vocal usage during travel and the fact that they seem to travel more than the northern residents.[4]

Location

The southern residents have been seen off the coast of California, Oregon, Washington (state) , and Vancouver Island, British Columbia. Historic sightings and more recent data from satellite-tagged individuals show frequent use of coastal waters as far south as Monterey Bay, California in the winter and early spring. Members of L pod have been seen as far north as Southeast Alaska. During the late spring through fall, the southern residents tend to travel around the inland waterways of Puget Sound, the Strait of Juan de Fuca, and southern Georgia Strait - an area known as the Salish Sea.[21] More information is now available about their range and movements during the winter months, which appears to follow the return of Chinook salmon to major rivers in California and North America's Pacific Northwest region.

Relationship with the Lummi Nation

The Lummi Nation has had a relationship with southern resident killer whales in the Salish Sea for thousands of years. Early proof of this can be seen in the recorded oral tradition of the tribes in the Puget Sound with the story "The Two Brothers' Journey to the North", which was first recorded in the mid-1850s.[22] The Lummi Nation refer to the southern resident killer whales as qwe'lhol'mechen, which translates to "people beneath the waves".[23] The term Sk'aliCh'elh is used to refer to the J, K, and L pods of the Southern Resident orcas by their "Lummi family name".[23] The Lummi Nation considers the southern resident killer whales as kin and has sacred ceremonies dedicated to them.[24]

Due to pollution, lack of prey, and previous whaling efforts, the orcas’ populations have recently been in decline. The Lummi have been making efforts using Traditional Ecological Knowledge (TEK) to support the orca population.[25] They are concerned about the future of the orcas if environmental issues that negatively impact the orcas continue to persist, and have been seeking support from agencies with the government to work harder in upholding the integrity of orca populations.[24]

J17, or Princess Angeline, is one such orca that has been under the care of the Lummi people in recent years. Before J17 passed away in 2019, the Lummi people practiced orca feeding ceremonies with J17.[24][26] The ceremony for the spiritual feeding involves first leaving the mainland on a boat to find a proper location. Next is the releasing of live and dead salmon, the live salmon to feed J17, and the dead salmon to honor the qwe'lhol mechen ancestors. The purpose of the ceremony is to hope that the condition of the orcas improves as well as to honor the orcas' ancestors.[24] In relation to such feedings, Lummi matriarch Raynell Morris has explained that "Here at Lummi when we see a relative starving, we don’t go in and do medical tests to see how much they are starving. We know they are and we do the right thing and we feed them."[27]


Distinguishing features

  • Dorsal fin: rounded at the tip (leading edge) and positioned over the rear insertion of the fin towards the back.
  • Saddle patch: typically seen as an "open" saddle patch; five different pigmentation patterns have been reported with similarities noted among clans within a community.[28]

Diet

Southern residents are fish-eating orcas that appear to prefer the Chinook salmon to other fish species. From visual sources, necropsy, and feces collection, the following food preferences have been reported:[4]

They can be known to play with porpoise.

Threats

The major threats to this very small community have been listed as:[4]

  • Decreased prey availability
  • Pollution and contaminants
  • Effects from vessels traffic and vessel sound

Decline in prey

The depletion of large quantities of fish in the marine environments, while personal fishing in the salmon’s upstream spawning grounds have further depleted stock replenishment.[29] Aquaculture has had a negative effect on world fish supplies,[30] including through the spread of pathogens to the wild fish stock. A study also found that Chinook salmon found in South Puget Sound have less fat than those farther north, causing an increased need for consumption.[31] Due to four dams in the Lower Snake River Dam System, native salmon flow has been heavily restricted, endangering both Chinook Salmon and Southern Resident Killer Whales.

Chemical contamination

Northwest orca are among the most contaminated marine mammals in the world, due to the high levels of toxic anthropogenic chemicals that accumulate in their tissues.[32] Implicated in the decline of Orca populations in the Pacific Northwest, these widespread contaminants pose a large problem for conservation efforts. While many chemicals can be found in the tissues of Orca, the most common are DDT, an insecticide, polybrominated diphenyl ethers, or PBDEs and polychlorinated biphenyls, or PCBs.[33] Each of these have detrimental physiological effects on orca,[34] and can be found in such high concentrations in dead individuals that those individuals must be disposed of in hazardous waste sites.[35]

Correlative evidence shows orca may be vulnerable to effects of PCBs on many levels. Research has identified PCBs as being linked to restricting development of the reproductive system in orcas and dolphins.[36] High contamination levels leads to low pregnancy rates and high mortality in dolphins. Further effects include endocrine and immune system disruption, both systems being critical to mammalian health and survival.[34] A study examining 35 Northwest orcas found key genetic alterations that caused changes to normal physiological functions.[37] These genetic level interferences, combined with the varied effects of PCBs at other physiological levels, suggest these contaminants may be partially responsible for declines in Orca populations.

Many of the chemicals that have been found to be toxic to the orca population continue to be widely used.[38] Conservation efforts are said to have difficulty making progress if the chemicals that harm the orcas continue to pollute the water they live in.[38]

Marine noise

Noise and crowding from tour boats and larger vessels interrupt foraging behavior, or scare away prey. The noise can mask echolocation causing difficulty with catching prey.[39] Also, sonar is speculated to cause hemorrhaging, and possibly death.[40]

Previous captures

Before the 20th century, orca populations in the Salish Sea likely numbered over 200.[citation needed] One day in 1970, approximately 80 orcas, or one-third of the population, were captured to be placed in aquariums and theme parks.[23] Since this event, the orca population in the Salish Sea has continued to decline to reach the status of endangered that it holds today.[41][unreliable source?] The orca commonly known as Tokitae, or as Sk’aliCh’elh-tenaut to the Lummi, was captured during this event and is the only live orca from the event, currently captive at the Miami Seaquarium.[23]

Conservation efforts

Both NOAA and Lummi nation have been making efforts to feed bolster the Southern Resident population, however, there is disagreement in the types of conservation efforts that should be implemented.[25] The Lummi believe that immediate action is necessary in order to sustain the already unhealthy orca populations, while NOAA believes in observing before taking action. The Lummi are using "traditional ecological knowledge" practices to help sustain the orca population, including feeding of malnourished individuals, which has been criticized by NOAA as unsustainable.[25] The groups have worked together though to create "helpful protocols" and strive for the overall wellbeing of the orcas.[24]

There was a Washington state-wide task force created in March 2018 to make recommendations on how to preserve the Southern Residents from extinction.[42] Some of the recommendations include stopping the use of hormone disruptors and other toxins in consumer products[43] and removing dams that interfere with the salmon's access to breeding grounds.[44]

Current conservation efforts are listed as:[45]

  • Support salmon restoration efforts
  • Clean up existing contaminated sites
  • Continue evaluating and improving guidelines for vessel activity
  • Prevent oil spills
  • Continue Agency coordination
  • Enhance public awareness
  • Improve responses to live and dead orcas
  • Coordinate monitoring, research, enforcement
  • Conduct research
  • Cooperation and coordination

On October 31, 2018, the Government of Canada committed $61.5 million to implement new protections for the Southern Residents.[46]

See also

References

  1. ↑ "The Endangered Species Act - Protecting Marine Resources". Office of the Federal Register. https://www.federalregister.gov/documents/2005/11/18/05-22859/endangered-and-threatened-wildlife-and-plants-endangered-status-for-southern-resident-killer-whales. 
  2. ↑ "Recovery Strategy for the Northern and Southern Resident Killer Whales (Orcinus orca) in Canada". http://www.sararegistry.gc.ca/document/default_e.cfm?documentID=1341. 
  3. ↑ "Orcas of the Salish Sea". Orca Network. http://www.orcanetwork.org/nathist/salishorcas1.html. 
  4. ↑ 4.0 4.1 4.2 4.3 4.4 "Recovery Plan for Southern Resident Killer Whales (Orcinus orca)". National Marine Fisheries Service, Northwest Region, Seattle, Washington. 2008. http://www.nmfs.noaa.gov/pr/pdfs/recovery/whale_killer.pdf. Retrieved July 26, 2017. 
  5. ↑ Southern Resident Orca Community Demographics, Composition of Pods, Births and Deaths since 1998
  6. ↑ Azpiri, Jon (January 2, 2017). "105-year-old orca known as 'Granny' has died, researchers say". Global News. Corus News. http://globalnews.ca/news/3156804/105-year-old-orca-known-as-granny-has-died-researchers-say/. Retrieved July 26, 2017. 
  7. ↑ Balcomb, Kenneth C. (December 31, 2016). "J2: In Memoriam". Center for Whale Research. http://www.whaleresearch.com/j2. Retrieved July 26, 2017. 
  8. ↑ Mapes, Lynda V. (July 24, 2018). "Southern-resident killer whales lose newborn calf, and another youngster is ailing". The Seattle Times. https://www.seattletimes.com/seattle-news/environment/southern-resident-killer-whales-lose-newborn-calf-and-another-youngster-is-ailing/. Retrieved July 31, 2018. 
  9. ↑ "How Southern Resident Killer Whales are Identified". Center for Whale Research. Archived from the original on November 28, 2009. https://web.archive.org/web/20091128230801/http://www.whaleresearch.com/orca_ID.html. 
  10. ↑ "Southern Resident Orca Community Demographics, Composition of Pods, Births and Deaths since 1998". San Juan Island: Center for Whale Research. July 23, 2013. http://www.orcanetwork.org/news/birthsdeaths.html. Retrieved July 26, 2017. 
  11. ↑ Gamby, Sonja (January 7, 2015). "Endangered species has hope with the birth of a baby killer whale". Modus Vivendi. Archived from the original on January 16, 2015. https://web.archive.org/web/20150116125323/http://www.modvive.com/2015/01/07/endangered-species-hope-birth-baby-killer-whale/. 
  12. ↑ "J52 "Sonic" died - 3rd of 6 "2015 baby boom" orca to die" (in en-gb). http://sanjuanislander.com/news-articles/environment-science-whales/whales-2/25728/j52-died-3rd-of-6-baby-boom-orcas-to-die. 
  13. ↑ Garrett, Howard. "Welcome to Orca Network". https://www.orcanetwork.org/Main/index.php?categories_file=Births%20and%20Deaths. 
  14. ↑ Mapes, Lynda V. (August 6, 2018). "Lummi Nation, biologists prepare to feed starving orca. But where is she?". The Seattle Times. https://www.seattletimes.com/seattle-news/environment/rescue-effort-for-sick-orca-underway-but-familys-location-remains-unknown/. Retrieved August 6, 2018. 
  15. ↑ "Births & Deaths" (in en-US). April 30, 2022. https://www.orcanetwork.org/births-and-deaths. 
  16. ↑ "J57". September 6, 2020. https://www.whaleresearch.com/j57. 
  17. ↑ "J41's new calf J58" (in en). https://www.whaleresearch.com/j58. 
  18. ↑ "L125" (in en). https://www.whaleresearch.com/l125. 
  19. ↑ "Error: no |title= specified when using {{Cite web}}" (in en). https://twitter.com/dfo_pacific/status/1417658093832482825. 
  20. ↑ "Female calf good news for endangered southern resident orcas" (in en). https://www.castanet.net/news/BC/370293/Female-calf-good-news-for-endangered-southern-resident-orcas#370293. 
  21. ↑ "Killer Whale (Orcinus orca)". NOAA Fisheries: Office of Protected Resources. June 25, 2014. Archived from the original on July 16, 2014. https://web.archive.org/web/20140716193655/http://www.nmfs.noaa.gov/pr/species/mammals/cetaceans/killerwhale.htm. 
  22. ↑ Clapperton, Jonathan (2019). "Whales and Whaling in Puget Sound Coast Salish History and Culture". RCC Perspectives (5): 99–104. ISSN 2190-5088. https://www.jstor.org/stable/26850627. 
  23. ↑ 23.0 23.1 23.2 23.3 "One stolen whale, the web of life, and our collective healing" (in en-us). October 28, 2021. https://grist.org/fix/lummi-nation-southern-resident-killer-whale-salish-sea-return/. 
  24. ↑ 24.0 24.1 24.2 24.3 24.4 "Lummi's sacred obligation is to feed orcas, our relations under the waves" (in en-US). March 3, 2019. https://www.seattletimes.com/opinion/lummis-sacred-obligation-is-to-feed-orcas-our-relations-under-the-waves/. 
  25. ↑ 25.0 25.1 25.2 Guernsey, Paul J.; Keeler, Kyle; Julius, Jeremiah 'Jay' (July 21, 2021). "How the Lummi Nation Revealed the Limits of Species and Habitats as Conservation Values in the Endangered Species Act: Healing as Indigenous Conservation". Ethics, Policy & Environment: 1–17. doi:10.1080/21550085.2021.1955605. ISSN 2155-0085. https://doi.org/10.1080/21550085.2021.1955605. 
  26. ↑ "'Our relatives under the water.' Lummi release salmon to ailing orcas" (in en). April 12, 2019. https://www.kuow.org/stories/lummi-ceremonial-feeding. 
  27. ↑ "Lummi Nation asks NOAA for emergency intervention to aid Puget Sound orcas" (in en). 2019-05-22. https://www.kuow.org/stories/lummi-nation-asks-federal-government-to-issue-an-emergency-intervention-to-help-puget-sound-orcas. 
  28. ↑ Baird, Robin William; Stacey, Pam Joyce (March 3, 1988). "Variation in saddle patch pigmentation in populations of killer whales (Orcinus orca) from British Columbia, Alaska, and Washington State". Can. J. Zool. 66 (11): 2582–2585. doi:10.1139/z88-380. http://www.cascadiaresearch.org/oldsite/robin/CJZkw88.pdf. Retrieved July 26, 2017. 
  29. ↑ Noakes, Donald J, Richard J Beamish, and Michael J Kent. "On the decline of Pacific salmon and speculative links to salmon farming in British Columbia." Aquaculture. 183.3-4 (363): 386.
  30. ↑ Naylor, R. L.; Goldburg, R. J.; Primavera, J. H.; Kautsky, N.; Beveridge, M. C.; Clay, J.; Folke, C.; Lubchenco, J. et al. (June 27, 2000). "Effect of aquaculture on world fish supplies". Nature 405 (6790): 1017–1024. doi:10.1038/35016500. PMID 10890435. Bibcode: 2000Natur.405.1017N. (Subscription content?)
  31. ↑ Cullon, D.L., et al. 2009. Persistent organic pollutants in Chinook salmon (oncorynchus tshawytscha): implications for resident orca of British Columbia and adjacent waters. Environmental Toxicology and Chemistry. 28:148-161.
  32. ↑ O'Neill, S, and J West. "Marine Distribution, Life History Traits, and the Accumulation of Polychlorinated Biphenyls in Chinook Salmon from Puget Sound, Washington." Transactions of the American Fisheries Societies. 138.3 (2009): 616-32.
  33. ↑ "Causes of Decline among Southern Resident Killer Whales". Center for Conservation Biology. University of Washington. Archived from the original on May 9, 2014. https://web.archive.org/web/20140509044124/http://conservationbiology.uw.edu/research-programs/killer-whales/. 
  34. ↑ 34.0 34.1 Ross, P.S, G.M Ellis, et al. "High PCB Concentrations in Free- Ranging Pacific Killer Whales, Orcinus orca: Effects of Age, Sex and Dietary Preference." Marine Pollution Bulletin. 40.6 (2000): 504–515
  35. ↑ Wotkyns, Sue; Khatibi, Mehrdad (May 10, 2012). "Fisheries Impact". Institute for Tribal Environmental Professionals & Northern Arizona University. Archived from the original on June 29, 2015. https://web.archive.org/web/20150629114900/http://www4.nau.edu/tribalclimatechange/tribes/northwest.asp. 
  36. ↑ "The Dolphin Defender: The effects of PCBs". Nature. PBS. June 12, 2008. https://www.pbs.org/wnet/nature/episodes/the-dolphin-defender/the-effects-of-pcbs/806/. Retrieved July 26, 2017. 
  37. ↑ Buckman, AH, N Veldhoen, et al. "PCB-Associated Changes in mRNA Expression in Killer Whales (Orcinus orca) from the NE Pacific Ocean."ENVIRONMENTAL SCIENCE & TECHNOLOGY. 40.23 (2011): 10194-10202
  38. ↑ 38.0 38.1 Mishael, Mongillo, Teresa; Maria, Ylitalo, Gina; D., Rhodes, Linda; M., O'Neill, Sandra; Page, Noren, Dawn; Bradley, Hanson, M. (2016). Exposure to a mixture of toxic chemicals : implications for the health of endangered southern resident killer whales. doi:10.7289/V5/TM-NWFSC-135. https://repository.library.noaa.gov/view/noaa/12818. 
  39. ↑ "Boat Disturbance". Wild Whales. Vancouver Aquarium. Archived from the original on June 17, 2016. https://web.archive.org/web/20160617023143/http://wildwhales.org/conservation/threats/boat-disturbance/. 
  40. ↑ Slaughter, Graham (December 9, 2011). "Whales, interrupted: How noise pollution from boats and sonar from ships hurt orcas". Canadian Geographic. http://www.canadiangeographic.ca/article/whales-interrupted. Retrieved July 26, 2017. 
  41. ↑ "Protect the environment/Right of nature" (in en-US). https://www.earthlawcenter.org/blog-entries/2019/10/the-lummi-nations-fight-for-rights-of-the-orcas. 
  42. ↑ "Puget Sound Partnership - Southern Resident Orca Task Force" (in en). http://www.psp.wa.gov/southern-resident-orca-task-force.php. 
  43. ↑ "Task Force on Contaminates meeting notes, Aug 7 2018". August 7, 2018. https://www.governor.wa.gov/sites/default/files/Contaminants%20Discussion%20Guide.pdf. 
  44. ↑ "Task Force on Forage Fish meeting notes". August 7, 2018. https://www.governor.wa.gov/sites/default/files/Prey_Hydro_Habitat_ForageFish%20Discussion%20Guide.pdf. 
  45. ↑ "Southern Resident Killer Whale (Orcinus orca)". NOAA Fisheries. June 3, 2020. https://www.fisheries.noaa.gov/west-coast/endangered-species-conservation/southern-resident-killer-whale-orcinus-orca. 
  46. ↑ "Government of Canada taking further action to protect Southern Resident Killer Whales". Newswire Canada (Fisheries and Oceans Canada). October 31, 2018. https://www.newswire.ca/news-releases/government-of-canada-taking-further-action-to-protect-southern-resident-killer-whales-699169241.html. Retrieved September 27, 2020. 

External links




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