Toxoplasmosis is cause of death for Hawaiian monk seal RH32

NOAA Fisheries has confirmed that toxoplasmosis was the cause of death for the Hawaiian monk seal known as RH32, or Ka'ale. The agency reached the determination after recent necropsy results and histopathology tests. RH32 was last seen on March 10, 2026, when he was hauled out at one of his regular West Oʻahu locations and showed typical behavior without outward signs of illness. He was recovered about two months later on May 6, 2026, off the coast of Nānākuli, Oʻahu. The parasite, Toxoplasma gondii, spreads through cat feces and can cause inflammation and organ dysfunction, affecting the brain, heart, liver, and lungs. NOAA says toxoplasmosis remains a leading threat to recovery, with 16 deaths attributed directly so far, and estimates the true population toll is higher. Regular sighting reports are emphasized as a key monitoring tool.