NARRATOR：

Now listen to part of a lecture on the topic you just read about.

FEMALE PROFESSOR：

Many experts believe that turtle excluder devices, also known as TEDs, are a very good way to protect endangered turtles, and that they should be a vital part of the equipment on any shrimp boat。

Here are their responses to the criticisms that you just read about.

First, it’s true that catching a turtle is a rare thing for any one boat.

However, there are, for example, thousands of shrimp boats operating off the southern coast of the United States.

Collectively these shrimpers accidentally catch thousands of turtles every year.

And these are endangered sea turtles whose populations are already too small, so harming several thousand every year is a big problem.

So when considering the impact of TEDs, don’t think in terms of an individual shrimper losing a few shrimp, but rather in terms of how the sea turtle population as a whole is affected by the shrimp industry as a whole.

Second, implementing time limits to ensure that the turtles are brought up for air in time—that sounds like a good idea, but only in theory.

The problem is that the time limits are almost impossible to enforce.

There’re thousands of shrimp boats far out at sea, and government patrol boats cannot really monitor the time limits all these boats use.

The use of TEDs is easier to enforce: all that’s required is checking the shrimp boats before they leave port and making sure their nets have TEDs.

Third, it’s true that TEDs can be too small for some very large species of turtle.

But in the areas where they’re needed, it’s not a problem to create TEDs that are somewhat larger.

The design of the TED can be modified easily without affecting the way that it functions.

So once larger TEDs begin to be produced, this will no longer be a problem.