Homo Sapiens, or humans.
Machines that rely on gas and oil, because they pollute and contaminate the atmosphere.
It would be difficult to determine the "biggest" threat to kiwi. Major threats are introduced animals such as dogs, cats and stoats. However, were it not for habitat loss, these animals would not be such a major threat.
+over grazing +over hunting +deforestation etc.
Animals that are facing extinction are cheeters and whale
Rivers, animals, Indians, and disease.
Animals rights activists are opposed to trapping animals because of the harm that it does to the animal. The animal can be injured or killed, and even without the threat of injury it stresses the animal and traumatic.
Yes, some plants can be venomous and pose a threat to humans or animals. These plants typically have toxic substances in their leaves, stems, or fruits that can cause harm if ingested or touched. It is important to be cautious around unfamiliar plants and to avoid contact with any plant that is known to be toxic.
Two major threats to the cacti are habitat destruction and commercial collecting of the plants.
Humans, hyenas, scavengers, and larger prey animals.
Jellyfish are eaten by squid. I believe that this is the biggest threat that they face.
Some plants are poisonous because they use it to keep threat from animals away. Unlike animals, they do not have the ability to move away from a predator and their only means of defense is to poison them.
the market economy was the single biggest threat