While many find joy in seeing bottlenose dolphins (Tursiops abbreviates) jump and swim in pods by the hundreds in coastal environments, researchers turn to them for insight into ocean health.
IN a new study published in PLUS ONEresearchers used blood tests to identify changes in gene expression in Gulf of Mexico blowfish from 2013 to 2018. These findings reflect the impact of 2010 Deepwater Horizon disaster and report on the health effects of bottlenose dolphins in Barataria Bay, Los Angeles. Effects include stress response along with reproductive, lung, heart and immune function, according to the study.
This is “a step forward for health assessments in the development of molecular markers of health and exposure that can be applied to improve the assessment and characterization of stress-related diseases in dolphins,” the study authors wrote.
Like top predator Feeding on squid, fish, crustaceans and cuttlefish, bottlenose dolphins keep the ocean environment in balance. They can be found all over the world, including the UK, mainly sticking close to the coastline.
They can live up to 40 or 60 years, and their bodies can absorb toxins in the water. This makes bottlenose dolphins are vulnerable human disturbances, such as feeding or underwater noise, and larger threats, such as recreational or commercial fishing and oil spills.
However, they are not threatened or endangered. Their strong connection to the environment gives researchers insight into the ocean’s health.
The goal of this new study was to identify molecular markers to study further and help wildlife researchers and veterinarians assess the dolphins’ health, according to the study.
Using tests to assess the blood chemistry of these dolphins, researchers identified many disease states following the oil spill. Tests include a complete blood count, stress levels and reproductive hormones. Diseases include inflammation, altered immune status, lung disease, impaired stress response and reproductive failure, according to the study.
They analyzed gene expression, which is common practice in human and veterinary medicine. A useful tool, these sensitive markers can measure health problems earlier than physical observations of disease or exposure, according to the study. Researchers can also provide health information without the need for a full physical evaluation of the animal.
“With further research, biomarkers may be developed that can provide critical health information to veterinarians, researchers, managers and other stakeholders, even in the absence of full veterinary assessments,” the study authors conclude.