An 80% decline in this period would categorize the species as critically endangered. Perhaps this is a good guideline in which we can asses native fish stocks.
By the end of the 20th century, many of the world's largest commercial fisheries have collapsed. The main reason was over-exploitation of fish-stocks, driven by social and economic incentives (Roughgarden et al 1998). The collapse of the commercial fisheries was sudden and some experts feel the same could hold true for recreational fisheries. With the technological advances and efficiency of modern sport fishing, people are more easily able to search for and exploit fish populations even when their abundance is low. Combined with modern technologies is an increasing human population which results in more anglers per fish population. Trying to counter this trend, management of fisheries have in many cases put in place restrictions on the number, length, or weight of any particular species that an angler is lawfully allowed to harvest. Philipp et al 1997, offer that limiting the extraction of a fish species per angler is only a start if each year there are more and more fishing licenses being sold per lake as human population expands and increases. As long as recreational fishing stays high in popularity, there will inevitably be an increase of anglers and therefore an increase of fish exploitation no matter the restrictions put in place.
A big question being asked is why are we not aware of a potential collapse like the one exhibited by commercial fisheries? Recreational fishing being a booming industry is one reason. As technology continues to improve ways for anglers to extrapolate diminishing stocks with more success, the demand on this resource is still being met. The sustainability of these methods is another question. Evans and Wilcox 1991, suggest that "it is difficult for individual anglers or management agencies to develop an accurate picture of processes occurring at scales longer and larger than their own experience.
