Baird is a false killer whale’s best ally—detailed, tenacious, articulate. He works with all of Hawai‘i’s eighteen species of toothed whales and dolphins, but he says that Pseudorcas are “the most interesting behaviorally.”
For example: Females, which can live into their 60s, go through menopause, a phenomenon experienced by less than 1 percent of animals. (From hagfish to horses, most animals continue breeding until they die.) A theory dubbed the “grandmother hypothesis” explains why this occurs. “The older females are likely passing on important cultural knowledge,” he says. “It’s the same as when you think of elders in a community. These individuals have experienced a lot; they know where the good fishing areas are and when there are oscillations in oceanographic conditions such as El Niño and La Niña, which might mean they need to do something different.”
Baird and his team have recently discovered that there are three different social subgroups among the Hawai‘i population. “It’s not that they’re always together, but it’s that they’re together more often than they are with anyone else,” he says. Although the groups overlap because they hunt throughout the main Islands, each has its stomping grounds. For one group, it’s northern Maui to northern Moloka‘i; for another, it’s the north end of Big Island to the southwest of Lana‘i. The last group has yet to be tracked with satellite tags; where they dwell is a mystery, as is why each group hangs out in these areas. Whatever the reason, the findings are important in terms of protecting critical habitat for Hawai‘i’s Pseudorcas.
In just twenty years the Hawai‘i population has dropped from 470 individuals to 150. There’s no single factor. Pseudorcas eat the same fish we eat—yellowfin, albacore and skipjack tuna, swordfish, ono, mahimahi and others. Overfishing, not just in Hawai‘i waters but also internationally, has caused a decline both in the number and size of fish. (Roughly sixty years ago, yellowfin tuna averaged 120 pounds; today they average about sixty.) Additionally, pollutants like pesticides and flame retardants, which are found in the fish as well as in the ocean and atmosphere, get stored in their blubber. This doesn’t necessarily kill them directly, but it can weaken their immune system.
False killer whales are also the most frequent cetacean bycatch in Hawai‘i’s longline fishery. They’re known to take hooked fish off lines, which causes roughly eight individuals per year to become seriously injured or die. To reduce bycatch and to comply with law, the National Marine Fisheries Service (NMFS) assembled a team of fishermen, conservationists and scientists (including Baird) in 2010. The group, known as the “Take Reduction Team,” made a number of recommendations. One suggests switching from “J” hooks to circle hooks, which could decrease the likelihood of a false killer whale getting snagged. The plan is expected to be finalized in 2012.
The NMFS has also proposed listing the population under the Endangered Species Act. If Hawai‘i’s false killer whales are granted protection—which will be decided in November 2011—NMFS must designate critical habitat. In this, Baird’s work will be essential.