Human Presence in the Gulf of Maine
Introduction: The human species has been an integral part of the Gulf of Maine ecosystem since the earliest native settlers in this region. To understand the human impact to the marine ecosystem, we must consider the historic and current patterns of human activity on land and in the sea.
Early human populations: Archaeological sites show human migration and consumption patterns which follow seasonal changes in both land and marine species dating back to the last ice age, approximately twelve thousand years before present. Since that time, human populations grew at a relatively slow and steady rate with minimal impact to the marine ecosystem. In addition to their smaller population, environmental impacts from Native American patterns of food production, consumption, and migration were relatively minor in comparison to modern populations.
Non-native human populations: The introduction of European settlers marked the beginning of significant change due to population growth and the patterns of natural resource consumption. New England and the Canadian Maritimes’ region were favored by the early immigrants due to its proximity and bounty of natural resources. The rate of human population increased steadily from the 1700’s onward, only showing a leveling off in the late 20th century.
Fishing impacts: Early seventeenth century English settlers were drawn to the abundant species of cod, haddock, halibut, tuna and shellfish, with historic accounts describing cod the size of men and oysters the size of a shoe (A Race Against Time, Woodard 2007). Advances in fishing technology showed a dramatic increase in “landings” throughout the 20th century, and at the same time, depletion and in some cases, the collapse of commercial species. Decades of overfishing caused the extinction and near-extinction of several larger marine mammals, such as the North Atlantic right whale whose current population is now estimated at around 300 in the Gulf of Maine. (University of Maine)
In addition, the excess removal of certain species or larger species can result in an imbalance in predator-prey relationships, causing the rise or decline of certain species within a community. For example, the Maine lobster population has shown spikes in recent years. Among several factors, some speculate that the removal of larger predators such as cod have helped to increase the bounty of lobsters in the region.
A predator-prey imbalance can cause a feast or famine, depending on one’s perspective, but either way, overfishing is likely the largest anthropogenic, or man-made, impact to the Gulf of Maine ecosystem.
Land use impacts: Significant changes to the landscape from forest clearing for grazing and agriculture in the 18th and 19th centuries resulted in increased run-off, excess nutrient and sediment loading to streams and rivers.
Agriculture gave way to industrialization, and with it the damming of streams and rivers for hydropower, the disposal of waste products and the introduction of impervious surfaces throughout the region brought about incremental but cumulative impacts to the watershed.
Significant impacts to the watershed and marine ecosystem continued to increase in both scope and magnitude throughout the 20th century due to human patterns of land use, consumption and waste disposal. A challenge to managing impacts is that the Gulf of Maine watershed falls within two countries, and is bordered by two Canadian provinces and three US states.
Current population trends: As of 2007, nearly 10.8 million people live in the Gulf of Maine region, which includes:
- in Canada, the maritime provinces of New Brunswick (.94 million) and Nova Scotia (.75 million), and
- in the US, the New England states of Massachusetts (6.45 million), Maine (1.32 million) and New Hampshire (1.32 million).
The current population growth in the region is just over 1%, as compared to the US and Canadian averages of less than 1%. This population trend and the migration of human settlement toward the coast will continue to impact the Gulf of Maine ecosystem for decades to come.
Climate change impacts: The indirect impacts associated with global climate change, including significant changes in sea level, temperature, salinity, currents, and increased acidification have only just begun to be understood. Some of these large-scale changes have been linked to changes in the Gulf of Maine ecosystem, such as an increase in harmful algal blooms from increase sea surface temperatures in recent decades. As data sharing between scientists and resource managers continue in the Gulf, more relationships and trends will come to light.
For a lesson plan on tracking daily, seasonal and long-term changes in the Gulf of Maine, visit the Changing Ocean
Sustainability: In addition to the indirect impacts of human land use patterns and climate change, the direct impacts associated with fishing have caused the changes in the size, distribution and abundance of marine species throughout the Gulf. Likewise, population growth and demand for commercial fish has created a crisis in fish stocks regionally and around the globe.
The ability of our marine resources to sustain these trends in world population and demand is demonstrated in the diagram below, i.e., the human population continues to grow, as does the amount of fish caught (world catch) but exceeds the rate of fish produced (marine production).
In the Gulf of Maine, researchers and scientists have come together in recent years to create science-based policy to manage this world-renowned fishery. Although no one believes that the fishery can be restored to historic populations, the hope is that we can better manage our future by understanding the ecosystem as a whole, and the integral relationship the human species has with the marine environment.
Although the latter part of the last century showed significant strides in environmental protection and resource conservation, human activities will continue to have adverse effects on the Gulf of Maine ecosystem. The Census of Marine Life hopes to understand how these changes have affected the diversity, abundance and distribution of marine life throughout the world, and the regional ecosystem pilot, the Gulf of Maine area program seeks to use this knowledge to improve the way the ecosystem is managed as a whole.