Determine whether the fishing of orange roughy east of Tasmania in the late 1980s and early 1990s was sustainable or unsustainable.

To determine whether the fishing of orange roughy east of Tasmania in the late 1980s and early 1990s was sustainable or unsustainable, we need to consider several factors:

1. Fishing Rates: If the fishing rates were higher than the rate at which the orange roughy could reproduce and replenish their population, then the fishing was unsustainable.

2. Fishing Methods: If the methods used for fishing were destructive to the habitat of the orange roughy or other marine life, then the fishing was unsustainable.

3. Population Trends: If the population of orange roughy significantly declined during this period and did not recover, then the fishing was unsustainable.

4. Regulatory Measures: If there were no effective regulatory measures in place to control the fishing of orange roughy, then the fishing was likely unsustainable.

To get a definitive answer, you would need to research these factors for the specific time and place in question. However, it's worth noting that orange roughy are known for their slow growth and late reproduction, which makes them particularly vulnerable to overfishing. In fact, orange roughy fisheries in many parts of the world have been declared unsustainable due to these factors.