Medical Director The Marine Mammal Center Sausalito, California
Free-ranging California sea lions suffer from one of the highest rates of cancer ever documented in any wildlife species. Approximately 20% of stranded adult sea lions that die or are euthanized at The Marine Mammal Center in California are found to be suffering from urogenital carcinoma. This particular cancer is linked to a sea lion gamma herpes virus as well as environmental pollutants such as DDT and PCB's, though a few other types of cancer have also been diagnosed and reported in sea lions and other marine mammals. This condition is usually diagnosed in live animals through physical examination and abdominal ultrasound, and by the time the sea lions strand (wash ashore), the cancer has usually metastasized in terminal condition. While treatment is too late for most of these sea lions, this condition is representative of the significant health challenges faced by wild marine mammal populations that in turn can act as health sentinels for the ocean, and thus ourselves.
