Then came the boats. Around the world, reports poured in of Orcas ramming and capsizing vessels. By late 2023, about 600 attacks were on record, and some of these ships sank. The governments of Spain and Portugal tasked a team of scientists to determine the cause of the attacks. The team produced a report that concluded the attacks were just for fun. This was playful behavior.

These two Orca “mysteries” were amplified by the media with separate, but equally ridiculous, anthropomorphic narratives.

It’s Not Fashion. They’re Not Playing.

A study published in 2022 found a correlation between elevated cortisol levels in the whales and increased vessel traffic and noise. When the ships went away, stress hormones went down, and vice versa.

I don’t have the qualifications those scientists do, but as one prominent Orca scientist told a reporter, “your guess is as good as mine.” Let’s find out…

“Honestly, your guess is as good as mine.”

Deborah Giles, Science and Research Director for the nonprofit organization Wild Orca, speculating on the Salmon hats.

Like a Restaurant With Insufferable Background Din…

Consider the underwater noise pollution from global shipping lanes. Low-frequency sound from vessels disrupts Orca echolocation, the finely tuned system they use to hunt and communicate.

Studies show that ship noise forces Orcas to shout louder and for longer just to be heard, burning valuable energy and interfering with their ability to find food. Imagine trying to hold a conversation in a nightclub where the bass never stops—except your survival depends on it.

Orcas Ship Attacks Peak With Sailing Season

The peak sailing months are June – August, when most attacks occur.

While Orcas breed all year round, most mating is in the summer, when boats are most active. For Orcas, the summer conditions are perfect for making love, and so it’s business time for Orcas. Studies have also found the echolocation activity of Orcas peak in the summer months, aligning with the frequency they are attacking ships.

The Function of the Hats & Purpose of the Attacks

A dead salmon could act as a noise filter, helping to shield sensitive areas like the Orca’s melon (the sound-projecting and receiving organ) or modulate echolocation signals. It’s more likely to be an Orca’s noise-canceling headphones (with gills) than a fashion accessory.

And the boat attacks? Playful rebellion, really? The whales are specifically targeting the rudder of the boats – tearing them off and then sinking the boat. They’re doing this when we know their stress hormones and mating season are both peaking. Orcas are social, cultural animals with the intelligence to solve problems and teach solutions to their pods. If vessels are the source of unbearable noise and habitat disruption, it’s not hard to imagine an Orca deciding, “Enough,” and confronting the problem. This is a deliberate message.

What’s truly baffling isn’t the behavior of the Orcas—it’s the absurdity of our responses. We’re watching a threatened species in crisis, and the best explanations we’ve come up with read like someone prompted ChatGPT with: “The Onion headline if Martha Stewart solved the Orca mysteries”. Speaking of which, if you like the Onion and read this far, my best writing is Some Kind of Diaper (Onion-like satire of science news).

Hypothesis: Technical

Below are some considerations. I am not a marine biologist, but since they can’t figure this out…here we go…

1. Theoretical Model of Ship Noise Interference

Orca Echolocation: A Quick Overview

• Frequency Range: Orcas emit high-frequency clicks (10,000–150,000 Hz) for echolocation, which are precisely directed by the fatty, acoustically specialized tissues of the melon.
• Echo Reception: Sound echoes return to the orca’s lower jaw, which conducts vibrations to the inner ear for interpretation.
• Goal: The orca builds an “acoustic image” of its environment.

Ship Noise Characteristics

• Frequency Range: Ships emit predominantly low-frequency sounds (10–500 Hz), which are far below the range of echolocation but can overlap with communication frequencies.
• Acoustic Energy: Low frequencies travel farther and penetrate more deeply into biological tissues, creating pervasive noise pollution in the ocean.

Interference Pathways

1. Acoustic Masking:
   • Low-frequency ship noise creates a “noise floor” that reduces the orca’s ability to detect faint echoes from its high-frequency clicks.
   • This is analogous to trying to hear a whisper in a room with a low, constant rumble (e.g., from an air conditioner).
2. Resonance Disruption in the Melon:
   • The melon’s fatty tissues are optimized to focus high-frequency sounds, but incoming low-frequency waves could cause vibrations.
   • These vibrations might scatter the focused echolocation beam, reducing precision and range.
3. Echo Distortion:
   • Ship noise could interact with returning echoes, adding noise or scattering them, which makes it harder for the orca to distinguish prey or objects.
4. Behavioral Costs:
   • To counteract interference, orcas may increase the intensity or frequency of their clicks, burning extra energy and potentially straining their vocal mechanisms.

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2. Hypothetical Role of the Salmon

Acoustic Properties of Salmon Tissue

• Composition: Salmon bodies are primarily muscle and fat, both of which have sound-absorbing qualities, particularly for low-frequency waves.
• Fatty Tissue Absorption:
  • Fat is known to dampen acoustic energy, especially in the lower frequency range. Salmon fat could act as a “buffer” for ship noise.
• Sound Scattering:
  • The irregular shape and density variations within the salmon could scatter incoming sound waves, reducing their direct impact on the melon.

Placement of the Salmon on the Melon

1. Blocking Incoming Low-Frequency Waves:
   • By covering the melon, the salmon could act as a physical shield, absorbing or diffusing low-frequency sound waves before they reach the orca’s melon.
   • This reduces vibrational interference with the melon’s precision.
2. Enhancing Focused Echolocation:
   • The salmon’s tissue might filter out low-frequency components of the orca’s own clicks, further refining the echolocation beam.
   • This would create a more directional, precise signal.
3. Reducing Backscatter:
   • External noise can scatter sound waves internally, creating “self-noise” in the orca’s acoustic system. The salmon could minimize this effect by dampening vibrations and stabilizing the sound projection.

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3. Quantifiable Predictions and Tests

To validate this hypothesis, we could propose measurable outcomes:

1. Noise Reduction:
   • Place low-frequency sound sensors near salmon tissue to quantify how much acoustic energy is absorbed or scattered.
2. Echolocation Tests:
   • Measure the precision of outgoing echolocation clicks in controlled environments, both with and without a salmon covering a model melon.
3. Behavioral Observations:
   • Study whether orcas wearing salmon hats are more common in noisy environments (e.g., near shipping lanes) than in quieter regions.

Read my other attempts at scientific elucidations…

• Craig’s Neosporosis Blog
• New Theory of Cancer