Humpback Whales Display Altruistic Behavior

A team of researchers from NOAA have published an analysis indicating that humpback whales are intentionally helping other creatures to escape attacks by orcas (killer whales).

The research began when Robert Pitman, a marine ecologist with NOAA Fisheries' Southwest Fisheries Science Center, observed a humpback whale come to the rescue of a seal after a pod of killer whales had knocked it off an ice floe in 2009. 

Another researcher had witnessed a group of humpback whales driving off a pod of killer whales that had killed a grey whale pup.

The researchers detail 115 incidents of humpback whales rescuing other creatures from orca attacks between 1951 and 2012. The results showed that in 89 percent of recorded incidents the humpbacks stopped the orcas at the beginning or mid-hunt. They noted that just 11 of the incidents involved rescuing humpback whale calves. The rest involved rescuing a variety of other marine creatures such as sea lions, gray whales, sunfish and harbor seals.

Humpback whales are the only cetaceans known to drive off orcas and regularly do it to protect their young. The researchers found that many of the humpback whales involved in rescues had scars that might have indicated that they were previously attacked by orcas themselves.

The researchers hypothesize that the humpbacks may be responding to memories they have or that it might be accidental to attempt to rescue other species as they respond to the sounds killer whales make when attacking. Another reason could be the close bond developed between members of a pod. This could generate a sense of protectiveness that resulted in either a subconscious instinct to protect, rather than a conscious decision.

After considering all of the possibilities, the team has concluded that altruism "could not be ruled out." The humpback whales might do it simply because they see another creature struggling and wish to help.