📉🐋 Blue Whales Are Going Quiet — and Scientists Are Worried Researchers analyzing underwater recordings off the California coast found that male Blue Whale songs have dropped by nearly 40% over just six years. The change isn’t random — it’s strongly linked to the massive marine heatwave known as “The Blob,” which disrupted ocean ecosystems and drastically reduced krill, the whales’ main food source. When krill is scarce, blue whales must spend more time searching for food and burn more energy