Teamwork Under the Waves: How Orcas Divide Roles to Outwit Herring

Teamwork Under the Waves: How Orcas Divide Roles to Outwit Herring

(IN BRIEF) Researchers from Italy’s Cnr-Ibf, Norway’s Orca Survey, Sweden’s Linnaeus University, and the University of Hawaiʻi with Picture Adventures have used drone videography to decode cooperative hunting in orcas (Orcinus orca). Their study in Current Biology identifies two complementary roles—powerful “strikers” and strategic “helpers”—that work together to herd and stun herring in shallow waters off Norway’s Vesterålen Islands. The fieldwork demonstrated that pairs of orcas hunting collaboratively achieve higher success rates than lone individuals. Role assignment correlates with size: larger orcas typically strike, while smaller ones assist. Moreover, the research highlights the stability of orca partnerships, suggesting that enduring social bonds and repeated collaboration enhance their collective efficiency, akin to athletes honing their teamwork over time.

(PRESS RELEASE) ROME, 4-Jul-2025 — /EuropaWire/ — National Research Council of Italy (Cnr-Ibf) scientists, alongside colleagues from Norway, Sweden and the United States, have uncovered the cooperative hunting strategies of orcas, pinpointing distinct roles and tactics within the pod. Published in Current Biology, the study leveraged aerial drone footage to scrutinize orca behavior in shallow coastal waters.

The investigation revealed two specialized roles among hunting orcas: strikers, which deliver forceful tail slaps to incapacitate schools of fish, and helpers, who corral and contain prey to aid their striking partners. Researchers from the Norwegian Orca Survey, Linnaeus University in Sweden, and the University of Hawaiʻi with Picture Adventures joined Cnr-Ibf to reconstruct these predatory dynamics in the herring-rich waters off Norway’s Vesterålen Islands.

Using drones to film killer whales (Orcinus orca) in action allowed the team to observe their maneuvers from above, providing unprecedented insight into their strategic coordination. “Watching the hunt from above is akin to viewing a match from the stadium stands,” says Paolo Domenici of Cnr-Ibf. “Orcas benefit greatly from teamwork, yet how they synchronize their movements remained elusive until now.”

Typically, hunting parties consist of two whales working in tandem, a formation shown to be far more successful than solitary efforts. Helper orcas flank and contain the herring, forcing them into tighter schools, while striker orcas deliver powerful blows to stun individual fish. The study also discovered a size-based division of labor: larger individuals predominantly assume striker duties, while smaller ones act as helpers.

A further intriguing finding is the persistence of long-term partnerships among hunting orcas. “These enduring alliances suggest that orcas not only form strong social bonds but also refine their cooperative techniques over time, much like teammates who train together season after season,” explains Eve Jourdain of the Norwegian Orca Survey. This research underscores the complexity of orca society and humanizes their hunting behavior by drawing parallels to organized team sports.

Media Contacts:

Paolo Domenici
Cnr-Ibf
paolo.domenici@cnr.it

Ufficio stampa:
Francesca Gorini Danilo Santelli
Ufficio stampa Cnr
ufficiostampa@cnr.it

Responsabile Unità Ufficio stampa:
Emanuele Guerrini
emanuele.guerrini@cnr.it
ufficiostampa@cnr.it
06 4993 3383

SOURCE: Consiglio Nazionale delle Ricerche