There are so many animals on this planet. We have animals that live in land, and animals that live in water. Some like to spend time in both places. And of these animals, some are mammals, some are cetaceans, and some fish to name a few. We as people have a responsibility to take care of the world that we live in and that includes animals. Sometimes that means doing nothing and letting them carry on with life. Other times they are sick or injured due to what we as people have done and we need to step in and help out. In the case of these animals that spend time in the water, they can sometimes get forgotten as we don’t see them as often. Unfortunately we as people can cause just as much damage in water as on land.
It is common for animals called cetaceans (dolphins, whales, and others) to become stranded on the beach. This can be for many different reasons; for example, physiological, psychological, or other unknown reasons. When this happens there are stranding stations around the world that you should contact and they will respond accordingly. Cetaceans will strand, but there are other animals that sometimes require our assistance as well. Like seals for example. They spend their time on/in land and water. They too can become sick, dehydrated, or separated from their mothers.
There are rehabilitation centers for cetaceans who have been stranded or wounded and need care. Depending on where in the world you are, you may be able to volunteer or work in those places after training. Depending on the health of the animal when stranded and other factors, determine the success of the rehabilitation and if they are able to be released back into the wild again.
A big reason why medics are called out to assist with these animals are because they have got caught in nets and other material within the ocean. There are medics who are trained to work with these wild animals and help to get them untangled, treated by a vet if needed, and then released into the wild again. There are special techniques to use when catching these animals so that we don't cause any more harm to them, and also keep ourselves from getting hurt. Most often the medics will remove the netting and release the animal back that same day. Other times the wounds are more severe and need treatment and antibiotics before being released. Care is taken to release the animals on or near the same beach where they were found.
"Ghost netting" is the phrase used for nets that have been left behind in the ocean. This entanglement can also occur with plastic or other materials in the ocean as well. Turtles get caught in netting but also commonly eat plastic bags as they look similar to jellyfish in the water.
Most of these things can be prevented as we take better care of the world we live in. Being cautious to clean up plastic from beaches and other areas where animals might see it. Taking care to clear nets from the water if seen and not leave them there in the first place. There are many different organizations that are helping to minimize these occurrences. If you have interested in getting involved and volunteering, see the links below.
For those in the UK there is a training course on how to care for stranded animals-http://www.bdmlr.org.uk/index.php?page=training-course