Southern Resident Killer Whales
The J, K, and L pods
Currently numbering 74 individuals that do not breed outside their acoustic clan, this distinct population segment (DPS) is a well-recognized and deeply iconic coastal species. Hunted and feared for decades, captured and used as breeders for entertainment, now researchers and the public are moving towards conserving their families and environment.
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big questions to ask:
Will they adapt to a changing world
before it's too late?
How can we help?
1.
Harmful Noise Levels
Vessel noise and sonar can mask killer whale communication which intern can impact feeding success among the whales. Jodi Smith's research from 1999-2001 found that just one vessel within 400m changed killer whale behavior from foraging to travel. Aggressive boater behavior around whales can all cause stress, harm and potential separation of pod members.
Whale watching is a popular activity, but please reconsider before you book a trip. While boats are required to be at least 100 yards away from whales, noise pollution can still negatively impact and mask whale communication between members.
2.
Deadly Contaminants
Persistent Organic Pollutants or POPs are highly toxic and carcinogenic contaminants that though banned in some countries, continue to persist within the environment. POPs such as PCBs and PCBDs magnify and bioaccumulate across trophic levels, and thus apex predators such as killer whales are particularly susceptible to their ill effects which can include immune suppression and reproductive failures.
Desforges et al. 2018
Bioaccumulation of toxins in high trophic marine mammals due to biomagnification from human, production and consumption. Deforges et al. 2018
What Are DDTs?
Dichloro-diphenyl-trichloroethane (DDT) is a highly toxic insecticide that was once used in abundance throughout the US, primarily as an agricultural pesticide. It was also sprayed in generous quantities at beaches and other public areas in order to kill mosquitoes as well as pests inside buildings.
DDT was later discovered to be disruptive for mammalian hormonal systems, appearing to induce breast cancer in women and testicular cancer in men and other deleterious health effects.
What is Bioaccuumulation?
The process by which a compound (such as a pollutant or pesticide) increases its concentration in the tissues of organisms as it travels up the food chain. Since Killer Whales are at the top of the food chain, they carry high levels of toxins in their blubber (fat).
2.
3.
A Dwindling Food Supply
Foraging specializations have enabled killer whales to feed on certain prey resources. For Southern Residents, endangered Chinook salmon makes up approximately 96% of their summer diet. With fewer salmon, the pods spend less time in traditional foraging areas such as Haro Strait, Washington.
photo: the seattle times
One of the lower Snake River dams in Oregon, blocking off key Chinook salmon spawning grounds and contributing to the steep decline in fish numbers.
Graph Data: CWR/NOAA Fisheries
Though historically the Southern Resident population was likely only between 100-200 individuals, they have experienced major declines periodically due to human impacts. Live captures in the 1970s and 80s removed small animals (typically female) for oceanariums and sea parks. In 1996 the population experienced a 21% decline over six years due to mortality. Since their ESA listing in 2005, they have slowly had a 10% decline. The struggling population continues to deal with the above factors impacting their survival.
Below is a quick snapshot of the types of whale conservation we focus on.
Migration Patterns
With the aid of public reported sightings and photo-ID, we are able to quickly identify pods and individual killer whales as they travel the NorCal coast. This allows for establishing critical winter habitat for the animals, as well as determining what types of populations are frequenting our coast.
Behavior
Data collection on species, numbers of animals and their behavior allows for establishing a picture of habitat use. Looking at whether animals are using the areas for travel, foraging, or breeding and socializing is vital to establishing conservation protocols for population longevity.
Climate Change
The response from whales to changing climate conditions can be reflected in their growth, distribution, and travel patterns. Studying changes in sightings, behavior, and even increasing underwater noise can establish normal from not normal shifts for animals and give us an idea of what we expose them to.
