PORTLAND – Six tamarin monkeys that died at the Oregon Zoo in May were under significant stress, but the specific cause of their deaths remained unknown, according to a report issued by an Oregon Zoo veterinarian.
Six of nine cotton-top tamarins, a species of New World monkey, died May 29 while in quarantine two days after arriving at the Oregon Zoo, according to zoo spokesman Hova Najarian.
A pathology report issued Tuesday says the tamarins were under stress but that it was not enough to have caused the death of the animals.
“The pattern and timing of these deaths does not appear explainable by stress alone,” said Oregon Zoo veterinarian Dr. Tim Storms.
The monkeys were found dead inside plastic coolers, according to a June 13 Willamette Week report. The report said zoo documents showed that the nine monkeys had been traveling for at least 50 hours in a van before arriving at the zoo.
The six died at the zoo’s veterinary center while in plastic coolers with holes.
On Wednesday, Najarian said that the cause of the monkey’s deaths was still unknown, according to the pathology report.
The zoo tested for possible causes like environmental toxins and gastrointestinal pathogens but results were inconclusive, Najarian said.
“Unfortunately, as much as we would like, we will never know the specific cause of death of these tamarins,” Storms said.
The remaining three monkeys, a 9-week-old female and her two older siblings, remain in good health, Najarian said.
In May, zoo director Kim Smith and veterinarian Mitch Finnegan were replaced following the death of the zoo’s Sumatran Orangutan Kutai, The Metro Regional Government, which runs the zoo, issued a statement regarding Kutai’s death, saying, “mistakes were made.”