The fishing industry cannot currently be relied upon to help the government count the seabirds killed by net fishing, since an accurate count might result in restriction of net fishing.
Conclusion (should therefore)
The government should institute a program where tissue samples from dead birds are examined to determine the amount of toxins in the fish eaten by the birds.
Evidence
The fishing industry cannot currently be relied upon to help the government count the seabirds killed by net fishing because an accurate count might result in restriction of net fishing.
The industry needs to know whether the fish it catches are contaminated with toxins.
Evaluate
This argument is making a Plan/Goal argument:
Plan: Implement a program to analyze bird tissues for toxins.
Goal: determine the amount of seabirds killed by net fishing.
The idea is that by instituting a program to test birds for toxins, the fishing industry will have an incentive to cooperate and turn in the bird carcasses because they are concerned about the potential contamination of fish. Meanwhile, the government will finally get the "dead bird count" they seek, to analyze the effect of net fishing on seabirds.
Goal
Let's look for an answer that makes us more likely to think that any part of this Plan will work as intended to get us closer to the Goal. We want to know that the fishing industry will indeed be motivated to turn in the seabirds they kill and that the government will thereby get a good sense for the number of seabirds being killed by net fishing.