Passengers on a whale-watching tour were treated to a surprise when they spotted not two, but what appeared to be three gray whales mating off the coast of Newport Beach, California earlier this month. The intriguing footage captured the three cetaceans encircling and rolling around each other while dolphins swim nearby. The footage was shot via drone by Mark Girardeau.
What appears to be mating, however, is simply an elaborate courtship in which two males can be seen attempting to mate with a female.
Christopher Fitzsimmons, an education specialist at the Birch Aquarium at Scripps Institution of Oceanography, explained that mating in pods of three, with two males and a female, is entirely common among gray whales.
"This rolling and rubbing we see is believed to be the whales familiarizing themselves with one another and making sure the female is receptive to mating," said Fitzsimmons.
Gray whales engage in often elaborate courtship practices before mating. Males will use their pectoral fins to coerce and align females into mating positions. Females have even been observed avoiding the attempts of males for days.
Bruce Mate, director of the Marine Mammal Institute at Oregon State University, confirmed that no actual copulation takes place in the video. One of the males can be seen with his penis out two minutes into the footage, but by turning her back to the male, the female signals a lack of interest. Because gray whales must mate belly to belly, this rolling behavior is the most obvious signal that a female is either uninterested or testing the rigor of the male.
As Mate puts it: "The females always have the upper hand."
Because gray whales are pregnant for approximately thirteen months and spend almost a year nursing, females are highly selective in choosing mates. They commonly mate during winter seasons in warmer waters near Baja, California. Once the female displays a willingness to pair up, she may mate with two or three males over the course of an hour.
"Many times gray whales do mating triads and at times one male props the other male up to mate and then they flip flop positions," said Professor Carrie Newell, a marine biologist and gray whale researcher. Fitzsimmons confirmed this cooperative male behavior in which an additional male helps the pair mate, saying among gray whales, watchers typically "don’t see direct or forceful competition among males."
In addition to the gray whales, bottlenose dolphins can be seen swimming and playing nearby in the video.
According to Fitzsimmons, dolphins can often be seen near large whale mating rituals and courtships. The reasons why are unknown but the dolphins may be attracted to the social aspect of the interaction.
"The gray obviously knows the dolphins are there and it appears that the gray is also having fun with the dolphins by swimming upside down," said Newell. She also noted that gray whales sometimes practice mating outside of times when females can become pregnant.
"Grays are very tactile creatures and are very intelligent. I think they probably mate just for the fun of it," she added.