Shipping is responsible for 69% of invasive species introductions to marine areas.
Since as early as 50,000 BC, humans have taken to the sea to travel and trade. Since its advent, shipping has evolved significantly— most ships now are built with metal rather than wood, are propelled by burning fossil fuels, are larger and faster, and have greater carrying capacities. Every technological advancement has enabled humans to travel further and further from land, opening the portal for faster and broader communication and trade between nations. Over the last few decades, the shipping industry has grown exponentially— both in number and in physical size of the ships. Today, more than 90% of international trade is carried by the sea. While shipping offers the most cost-effective way to move en masse goods around the planet, it also poses the potential for more widespread environmental degradation.
Smokestacks tirelessly pumping chemical exhaust, destructive port dredging and pier construction, accidental groundings resulting in cargo and fuel oil spills, the assisted spread of invasive species, deadly collisions with marine mammals, propellers churning the discharged ballast, grey, and black water— ships have undeniably made their mark on our marine ecosystems.
Boat anchors and groundings, even by smaller recreational boats, cause considerable, long-term harm to coral reefs— shattering, dislodging, and fragmenting entire coral colonies. Large sharks (e.g. whale sharks and basking sharks), sea turtles, and marine mammals alike spend much of their days feeding, breathing, or basking in the warmth near the surface of the water. Lingering near the surface makes these marine animals very vulnerable to ship traffic, and if not immediately killed by a collision, the animal will typically die soon after from its injuries. Marine mammals and corals face an additional threat in the form of the the loud cacophony accompanying commercial, recreational, and passenger vessels. Since water amplifies and echoes any sound ten fold, noise from ship traffic— which doubles every decade— has reached deafening levels, undermining marine mammals’ ability to communicate and hunt, and coral larvae’s ability to orient themselves.
The future of our polar seas has perhaps the most to lose with the expansion of the shipping industry. As waters warm and sea ice melts, more shipping routes through the Arctic are opening up. While potentially economically beneficial for the shipping industry, more Arctic shipping means more risks of groundings, oil/chemical spills, invasive species, animal collisions, and pollution. Even now with limited vessel crossings, shipping is responsible for 8-13% of all black carbon—the biggest contributor to climate change after CO2—in the Arctic Circle.
As maritime traffic grows around the world, more and more ocean ecosystems will directly and indirectly suffer, unless proper regulation and common sense are utilized. If not, we’re all going overboard.