Take Heart!
From Christian Vegetarian Association (CVA)

And... what about fish?

This is a question that vegetarians are asked frequently. It seems fish, by not being mammals or land animals, tend to be thought of as less deserving of compassion or humane treatment. However, regardless of the inherent cruelty of the fishing industry, fish is the most contaminated food in the planet (mercury and PCBs), known to pose health hazards to pregnant women and children.

In addition, there’s another issue not many people think of and it’s the effect of discarded or forgotten nets in the fauna of oceans and rivers. Tangling in fishing nets kills thousands of dolphins, whales and turtles each year, as well as many other aquatic species. These nets, made of a very resistant nylon, can take hundreds of years to degrade and thus “catch” anything in their path for a very long time.

Taking into account the consequences of our treatment of animals can shed light on the importance of being good stewards of all of God’s creation.

Read more at Animal Issues