Sloths

50% of sloth deaths occur during their once a week trip to the ground to dig a hole and defecate. They are near blind and can only see about 3 inches in front of them. They can’t self-regulate body temperatures very well. Therefore the temperature and humidity have to be perfect for them to survive. They use fermentation to digest food, so if they are fed too many fruits they may die from alcohol poisoning. They're so lazy that despite the female being in heat, the male sometimes just falls asleep/lacks interest, leading to a huge lack of reproduction. You have to whisper while you're with them otherwise they may get too stressed and have a non-symptomatic heart attack and die.