We have some unfortunate diagnostic findings regarding the three monk seals that were found dead on Oʻahu from May 15–17, 2018. Extensive tests showed that all three seals (two adult females, RK60 and RT10, and one unborn female pup) died of toxoplasmosis, a disease that causes multiple organ dysfunction and failure. The tests revealed no signs of other illness, toxicity, or trauma and determined that toxoplasmosis was directly responsible for these deaths.
This brings the total known Hawaiian monk seal mortality count from toxoplasmosis to 11 (since 2001). However, the number of disease-related deaths is probably higher because more seals die each year than are found dead or are examined. Infections appear to be predominantly affecting females (8 of 11 seals). This is especially concerning—considering that the loss of one female means the loss of her future generations as well. Toxoplasmosis is now the leading disease-related cause of death for Hawaiian monk seals.
For more information, download the toxoplasmosis fact sheet and infographic.
If you see a monk seal, healthy, ill or injured, please call (808) 220-7802 on Oahu and (888) 256-9840 for our neighbor islands.