Determining the cause of whale strandings, whether it's due to stress, illness, or other factors, is a complex process that requires the collaboration of various experts, including marine biologists, veterinarians, pathologists, and wildlife researchers. Several methods and techniques are employed to investigate the potential causes of whale strandings:
Necropsies (Autopsies): When stranded whales are found dead, necropsies (animal autopsies) are performed on the carcasses to examine their internal organs and tissues. These post-mortem examinations can reveal signs of illness, injuries, or other abnormalities that might have contributed to the stranding.
Sample Analysis: During necropsies, tissue and fluid samples are collected from the stranded whales. These samples are sent to laboratories for further analysis, including toxicology screenings, bacterial and viral testing, and histopathology. These tests can help identify specific diseases, toxins, or infections that may have affected the whales.
Health Assessments: In some cases, live-stranded whales may be subjected to health assessments if they can be safely refloated or are near shore. These assessments can include physical examinations, blood sampling, and non-invasive imaging techniques, such as ultrasound and thermography. These data can provide insights into the health status of the live whales and help identify potential stressors or health issues.
Environmental Factors: Researchers also consider environmental factors that could contribute to whale strandings. These factors may include changes in water temperature, ocean currents, prey availability, pollution levels, noise pollution, and human activities that could disturb or endanger the whales.
Satellite Tags: Satellite tags or tracking devices may be attached to live whales before release (in cases of live strandings). This allows researchers to monitor their movements, behavior, and health remotely and gain insights into how they respond to their environment after stranding events.
Genetic Studies: Genetic analysis of stranded whales can provide valuable information about population structure, migration patterns, and kinship relationships, helping researchers understand the overall health of the whale population and identify potential genetic factors contributing to strandings.
Historical Data: Long-term databases of stranding events and associated factors can be invaluable for identifying patterns and trends that may suggest certain stressors or health issues affecting the whales.
It's essential to emphasize that determining the cause of whale strandings can be challenging, and in many cases, a definitive cause may not be identified. Strandings can result from a combination of factors, and sometimes the cause remains unknown. Nonetheless, the data collected from these investigations help wildlife experts better understand and conserve marine mammal populations and inform conservation efforts.