Photo Credit: SeaWorld San Diego
By Danielle Cookish
New research is being conducted at SeaWorld San Diego which has the potential to help the endangered Southern Resident killer whale population in the Pacific Northwest.
The study is being conducted to assess the dynamics of persistent organic pollutant (POP) transfer from female killer whales to their calves during gestation and lactation.
SeaWorld San Diego
Basically, scientists are looking to find out if the adult female killer whales that are suffering from pollution in their wild habitats are passing those pollutants to calves through their milk.
Dr. Dawn Noren is a research fishery biologist with the National Marine Fisheries Service’s Northwest Fisheries Science Center in Seattle. Dr. Noren is working with SeaWorld to gather data through milk and blood serum samples from Kalia, a lactating female killer whale who gave birth to her calf Amaya in December, 2014.
Dr. Noren said,
“The dynamics of pollutant transfer over the course of lactation have been studied in live pinnipeds, but are less understood in cetaceans. Because the life history patterns of pinnipeds differ from cetaceans, studies conducted on cetaceans, specifically killer whales, are warranted.”
By analyzing the samples collected from Kalia, Dr. Noren will assess the transfer of contaminants from females to their calves during lactation. Additionally, blood samples from Amaya will also be analyzed.
SeaWorld San Diego
The levels of POP are very high among Southern Resident killer whales. These pollutants have been linked to reduced immune efficiency, and reproductive failure in other wild animal species. The compounds are transferred during both gestation and lactation causing health implications, particularly to first-born offspring as they receive higher, more potent concentrations of these compounds through maternal transfer.
“We are aiming to determine when the bulk of contaminants are transferred from the mother to her calf during a one-year lactation period and estimate the proportion of the female’s contaminant body burden transferred to her calf during this period,” said Noren. “We also want to quantify pollutant levels circulating in the blood of the female and calf to assess when during the lactation period young wild killer whales and their mothers might be most susceptible to health effects from contaminant exposure.”
Noren’s research is a first-of-its-kind study that is crucial in analyzing contaminant transfer from female killer whales to their calves as well as determining circulating pollutant levels.
Repeated access to healthy killer whales at SeaWorld over the course of lactation in a controlled and safe environment is the only way Noren’s research is possible. This research study is a prime example of how SeaWorld collects data that cannot be collected from wild animals and uses that information to further our understanding of these animals and how to protect them in the wild. Gaining knowledge such as this will have a direct impact on wild killer whales currently suffering from polluted and toxic habitats.
SeaWorld San Diego
SeaWorld San Diego’s senior veterinarian Todd Schmitt said, “Our killer whales have been trained to participate in their own husbandry care which allows us to assist researchers in a variety of important scientific studies. In the case of this study, even though the pollutant levels in SeaWorld killer whales are lower than that of the Resident whales due to their distinct diets, the results of this study can still be used to develop a clearer picture of the contaminant transfer process from females to their calves.”
Many of the behaviors you see during performances, like the slide-out, have been trained as part of animal husbandry, to allow trainers, animal care specialists, and veterinarians to examine and care for the whales. All of the killer whales are trained to roll over and present their tail flukes and give a blood sample when necessary. But, as always, if the animal makes the decision to not participate, that decision is respected.
This study has begun with Kalia, but data collection will continue with killer whale mothers and calves over the next several years.
Click here for more information about NOAA, NOAA Fisheries Northwest Science Center, and a 10-year report which discusses contaminant concern.