Florida Atlantic University Finds Blacktip Sharks Detect Low-Frequency Sounds Up to 74 Meters Away

Insights into Blacktip Shark Hearing

According to НВ — Техно: A study conducted by Florida Atlantic University revealed that blacktip sharks (Carcharhinus limbatus) can perceive low-frequency sounds from as far as 74 meters. When exposed to these sounds, the sharks often alter their swimming direction, moving away from the source. Researchers used an underwater speaker, hydrophones, and a drone to monitor shark behavior along the coastal waters of Southeast Florida.

Sound Response Patterns

The analysis showed that blacktip sharks responded to low-frequency sounds within 100−200 Hz, 200−400 Hz, and 400−800 Hz ranges. In contrast, a control sound at 10 kHz triggered no reaction, consistent with the species’ limited hearing range. Over 70% of the sharks’ responses occurred in the far-field acoustic zone, indicating their heightened sensitivity to lower frequencies that can be detected from greater distances and lower volumes.

Unlike many fish, blacktip sharks lack a gas-filled swim bladder, which influences their auditory system. Their primary hearing organ is the inner ear, particularly the sensory macula neglecta. The use of drones to observe shark behavior in nearshore environments highlighted the need for further research on shark sensory systems in the open ocean, where acoustic distortions common to enclosed basins are absent.

This research emphasizes the crucial role of understanding marine animals’ sensory capabilities, especially sharks, which are vital to maintaining ocean ecosystem balance.

The discovery of blacktip sharks’ ability to detect low-frequency sounds has important implications for developing improved conservation strategies and assessing how human activity impacts marine habitats.