Learning from tragedy
From studying stranded cetaceans, we learn about their:
- health and diseases
- behaviour among the same, and between different, species
- the effects of pollution
- causes of death and threats to survival
Cause of death
There are a variety of causes of death to UK whales and dolphins.
- Entanglement in fishing nets, known as bycatch.
- Marine pollution: a wide range of pollutants are discharged into the sea including heavy metals such as mercury, pesticides and industrial chemicals. Untreated sewage may also present the threat of infection.
- Infectious diseases: parasitic lung infection, pneumonia or fungal infections.
- Over-fishing: mackerel, herring, sprats and sand eels have all declined in British waters, depriving cetaceans of food.
- Disturbance and accidental collision with boats and propellers.
- Noise pollution: human noise, including commercial dredging, potential effects of naval sonar, busy shipping lanes.