Cetaceans are presently under several threats. In general, these threats affect the large cetaceans as well as the small cetaceans. Historical threats have been existing for a long time and their effects are relatively well known. It should however be noted that new threats have emerged recently (e.g. pollution from marine debris) and that their impact on the population of cetaceans has still not been well researched.

Cetaceans are therefore facing various threats simultaneously. For example, even if a whale manages to survive poisoning caused by chemical substances, its immune system will be severely damaged. It will probably end up dying of disease or by running aground. The accumulation and synergy of these threats are very disturbing but this topic is still more difficult to study.

Several companies and scientific committees are studying marine mammals and especially the consequences of global changes and other threats hanging heavily on their future.

In Belgium, several programmes on cetaceans come under the scientific policy and The Royal Belgian Institute of Natural Sciences (IRSNB) and involve the academic world.

At the European level, the European Cetacean Society brings together European researchers in this field and holds an annual conference. The last one took place at Liege from 5 April to 10 April 2014.

In general, there are:
Historical threats such as hunting, bycatches and collisions with ships
New threats such as pollution, climate change, emerging diseases, etc.