Recent Studies Document Unusual Whale Behaviors in Gulf of California and Global Waters

Two separate studies published in peer-reviewed journals have documented previously unrecorded behaviors in orcas and humpback whales, based largely on footage captured by tourists and citizen scientists.

Orca "Ram-to-Fragment" Behavior in Gulf of California

In July 2024 and September 2025, tourists aboard vessels in the Gulf of California filmed orcas (killer whales) engaging in a feeding behavior that had not been previously documented.

Footage shows an adult orca holding a large sunfish carcass near the water's surface. The orca released the carcass, and a second adult orca swimming upward from below rammed the carcass, causing it to fragment into pieces. A younger orca then fed on the resulting fragments.

This behavior, termed "ram-to-fragment" by researchers, was detailed in a study published in Frontiers in Ethology. The researchers stated that the behavior may allow for prey sharing among pod members or serve a social function. The observations were enabled by citizen scientists using underwater cameras from tourism vessels.

Humpback Whale "Gaping" Documented in Global Waters

A separate study, co-authored by Dr. Vanessa Pirotta from Macquarie University, analyzed 66 instances of humpback whales holding their mouths open for extended periods without prey present. This behavior is referred to as "gaping."

The study analyzed videos sourced from the internet and social media. The footage was contributed by tourists, whale-watch operators, and drone users. Recordings were captured from boats, during swim-with-whale activities, and via drones.

The behavior was observed in both adult whales and calves. In most instances, the gaping occurred when other whales were nearby and outside of normal feeding routines.

According to the researchers, humpback whales typically open their mouths wide during feeding to take in water filled with krill or small fish, then expel the water through baleen plates to trap prey. Gaping is distinct from feeding, as it occurs in the absence of prey.

The study's authors proposed several hypotheses for the gaping behavior, including:

• Communication
• Social or playful interactions
• Exploring ocean debris (particularly for calves)
• Cleaning baleen
• Jaw stretching
• Reaction to a jaw-related issue

The researchers stated that the precise cause of the behavior remains unknown.

"Just when we think we know a lot about humpback whales, we don't," said Dr. Vanessa Pirotta. "Tourism operators and citizen scientists spend hours observing whales and are a powerful resource for capturing and reporting on behaviour."

Dr. Pirotta noted that tourism operators and citizen scientists spend extended periods observing whales and have access to increasingly high-quality recording technology.