Drift Nets, Seine Nets, and Dolphins living in Captivity

Drift Nets

Drift nets are nets that are often up to 64km long. They form a curtain that traps everything that crosses its path. These nets are a danger, not only to the fish that they are designed to catch, but also to sea turtles, dolphins, whales and sharks. All these animals get caught and drown in the nets only to be discarded by the fishermen, when they keep only the fish they intended to catch.
These incidents increase as the fish stocks decrease due to overfishing.

Seine Nets

Seines Nets are another lethal danger for dolphins. They are nets used for Tuna fishing. As Tuna often swim just below the schools of dolphins, the net which the fishermen use to encircle the fish also catches, and kills dolphins. When this type of fishing started in the 1950s it killed over a quarter of a million dolphins a year. Now fishermen are being educated, and taught methods to avoid killing the dolphins. With these new methods, now "only" 20,000 dolphins die in these nets every year. 

Dolphins Living in Captivity

Dolphins are highly adapted to their environment. They are streamlined, they have a skin that allows moving through the water with barely any friction. They live in schools, and have a complex family life, in which they care for each other. They are highly intelligent. They have a higher brain mass to body weight ratio then men. 

And we have been abusing this for years, by taking individual animals out of their environment, and placing them in small pools for our entertainment. And even though these animals are fascinating and beautiful to watch, one has to consider the following before visiting a theme park that presents dolphins as an entertainment:

• 53% of those dolphins who survive the violent capture die within 90 days.
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• The average life span of a dolphin in the wild is 45 years; yet half of all captured dolphins die within their first two years of captivity. The survivors last an average of only 5 years in captivity.
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• Every seven years, half of all dolphins in captivity die from capture shock, pneumonia, intestinal disease, ulcers, chlorine poisoning, and other stress-related illnesses. To the captive dolphin industry, these facts are accepted as routine operating expenses.

All of this proves that keeping dolphins captured is an imprisonment that is cruel, and unnecessary. (The UK has no captive dolphins) 

(http://www.idw.org/html/dolphins_in_danger.html)