Alejandro Arias, the species coordinator of FVSA's marine program, says 80 percent of the gull attacks are aimed at female whales and calves.
Southern right whale mothers spend a quarter of their day fleeing seagull attacks, according to FVSA.
But Bertellotti, the Patagonia University biologist, says it is unlikely that female blubber tastes better.
"The attacks are directed at all whales," he said. "The mothers receive more attacks because they pass more time along the surface when they are with their claves."
"The calves are the most affected because of [their softer skin] during first days of life and because they spend more time at the surface," he added.
The whales are significantly outnumbered by the gulls.
About 10,000 southern right whales use the coastal waters off Argentina , Australia, and South Africa as nursery areas, according to FVSA.
Meanwhile, 75,000 reproductive kelp gull couples occupy six main colonies along the Argentine coast, the group says.
(See Argentina photos, maps, more.)
Attacks on the Rise
British researchers first observed the attacks in 1969.
The number of aggressive birds has grown as the gull population has increased thanks to an abundance of human-supplied food sources in coastal towns.
Though the number of attacks has gone up, the attacks occur sporadically.
"Without a doubt, the attacks are not constant," Bertellotti said. "There are months when they are more frequent, and at other times they are nonexistent."
Arrias says FVSA is working to raise local awareness.
"In some places we are seeing a decline or stabilization of gull populations thanks to some changes," said Arrias, noting that at least one community, Puerto Piramide, has covered its landfills.
His group is also studying how the attacks will affect the region's whale-watching industry.
Scientists also want to know if the attacks are changing the whale's regional distribution patterns.
"I don't think the attacks are producing redistribution," Bertellotti said.
But the biologist plans to outfit some whales with specialized "suction caps."
The tracking devices will help chart the whales' movements to better understand the effects of the seagull attacks and other disturbances, he says.
Fellow Patagonia Univeristy biologist Gustavo Pagnoni has also studied the problem.
He notes that the growing gull population can put a territorial squeeze on some bird species.
But Pagnoni maintains that not all human development along the coast has prompted negative impacts.
The same human-supplied free lunch that boosts kelp gull numbers also draws other birds that increase local species diversity, he says.
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