Save the Whales, Save the Oceans
GWC is excited to announce a new education/outreach effort to protect Great Whales based on the relationship between the Great Whales and the health of our oceans and our atmosphere!
The scientific community now understands whales are not simply a major consumer of krill and fish, but play a critical role in sustaining the very krill and fish populations upon which they feed. Blues, fins, and humpbacks must consume massive quantities of small fish and krill (an inch-long shrimp-like crustacean) to survive. Those fish and krill populations feed on millions of zooplankton (tiny, non-swimming animals.) The zooplankton feed on massive blooms of phytoplankton (tiny, non-swimming plants.) The phytoplankton require certain nutrients to be in the water, such as iron (Fe) and nitrogen (N,) to photosynthesize and make their own food. This chain of inter-relationships isn’t linear, it’s circular – much of the Fe and N the phytoplankton require is provided by, you guessed it, the Great Whales.
There are two mechanisms by which whales appear to play a fundamental role in this circle of life. First, as they return to the surface after diving their movements carry along nutrients such as Fe and N, as well as sinking phytoplankton, back into the photic zone. (The photic zone = upper ~20 meters of the ocean where there is sufficient light to allow for photosynthesis.) Second, whales urinate and defecate (pee and poop) most often at the surface, which also results in the release of significant amounts of Fe and N into the photic zone. The whales’ role in returning these essential nutrients to the surface is known as the “whale pump.”
Our understanding of the whale pump was stimulated in part by studying what is known as the “krill paradox.” When millions of whales were taken out of the ocean by the commercial whaling fleet, everyone expected a huge increase in the number of small fish and krill. After all, their largest predator was being removed from the ecosystem. But that’s not what happened. In fact, the volume of krill and small fish did not increase it declined – hence the term “krill paradox.” It is now believed that removal of the whales caused substantial reductions in the krill and small fish populations because the limiting factors in the ecosystem were the concentrations of Fe and N, and these nutrients disappeared from the photic zone when the whales were taken away.
Simply put: more whales more nutrients more phytoplankton more zooplankton more small fish and krill more whales.
What does this have to do with saving the oceans? The greatest remover of CO2 from the atmosphere and the oceans, as well as the producer of half of the world’s oxygen, are phytoplankton, those tiny, non-swimming plants floating on the surface of the sea. When they photosynthesize, they use energy from the sun to combine water and CO2 and make carbohydrates (complex sugars.) As a byproduct of photosynthesis, phytoplankton release the oxygen into the atmosphere we need to breathe. The amount of CO2 removed by the world’s phytoplankton surpasses the quantity removed annually by all the world’s forests.
So – if more whales results in the production of more phytoplankton, having more whales would lead to the removal of more CO2 from the atmosphere. No one knows exactly how much impact increasing whale populations would have on lowering levels of CO2 in the atmosphere, but any reduction would help slow the change in our climate, and decrease the advance of ocean acidification – and that would be a good thing. Saving whales might just help us save the oceans, and ourselves.
Here’s What GWC is Doing
GWC is helping further the research on the whale pump phenomenon and its relationship to climate change. We are working with scientists at Harvard to learn more about whale poop, collecting samples to be evaluated for their potential to stimulate phytoplankton growth.
GWC is distributing information on this issue to the public and the press to help demonstrate the very real connections between all parts of the ocean ecosystem and land-based ecosystems as well, all of which depend on each other for survival.
GWC is working to create stronger relationships between ocean protectors and climate change advocates, who now share a common cause and a potential solution.