In 1862 Thomas Henry Huxley, friend and promoter of Charles Darwin, was appointed to a commission to examine claims by driftnet herring fishermen that long liners were adversely impacting fish catches due to local overfishing (Kurlansky, 1997). The commission that Huxley served on dismissed the requests of the fishermen to restrict long lining and declared the complaints to be unscientific. Huxley held the view that nature was almost infinitely resilient and would adapt to any pressure that humans could exert on the environment. This belief was shared by many not only through the nineteenth century but well into the twentieth.
As important commercial fisheries such as the Atlantic cod have collapsed toward the end of the twentieth century, scientists, environmentalists, and law makers have had to seriously challenge this assumption. Fishery biologists such as Myers and Worm (2003) have estimated that the biomass of large predatory fish has been depleted by at least 90% compared to pre-industrial levels. This assertion does not come without controversy, as conclusive stock assessments of fish populations can be difficult to obtain. Ocean fisheries are particularly difficult to assess, as populations can be widely distributed, are frequently migratory, and can be affected by environmental conditions such as water temperature and current patterns.
Also there is the human element to assessment. A problem that ecologists have
identified regarding measuring fishery populations is shifting
base lines. When ecologists study declining populations, there
is a tendency to judge the population based on the life-time memory
of those who study the organisms (Roberts,
2007). Older ecologists will remember the abundance of their
youth and will assume this represents a normal population level.
When a population has been declining over a period of decades
or even centuries, this creates a skewed vision of the organisms'
functioning role and carrying capacity within an ecosystem. To
obtain a better understanding of declining fisheries, scientists
have begun to look to history for answers regarding how much exploitation
aquatic species have been subjected to over time, and what undepleted
population levels may really have been. Some scientists and historians
have suggested that it is necessary to look back at least as far
as the Middle Ages to better understand what unexploited aquatic
resources may have looked like (Roberts,
2007; Bolster, 2008).
This Discovery Guide examines what some historians, archaeologists,
and ecologists have been able to uncover regarding the use of
fishery resources by European populations in pre-industrial times,
particularly pertaining to the Atlantic and Mediterranean regions.
Go To Ancient Mediterranean and Black Sea