|This month, Coral Crew Member and Director for the Center For Cetacean Research and Conservation in the Cook Islands, Nan Hauser, takes us inside her work with NASA on the ways in which whales are bio-indicators of climate change. In the following Q&A, she highlights why the survival of whales as a species is vital to the health of our oceans, and the problems she’s seen firsthand that are contributing to their decline.
Q: How do whales positively contribute to healthy ocean eco-systems?
A: Whales positively contribute to a healthy ocean eco-system by stimulating the growth of phytoplankton from the nutrients found in their poop. Theses nutrients pull carbon from the atmosphere and therefore provide a cleaner and healthier breathing environment for all animals, including us! Because there are whales on the planet, approximately 400,000 tonnes of carbon are extracted from the air every year. This contributes to feeding other species (like fish) that feed on phytoplankton for their survival. All of this helps to keep the food chain in balance.
Q: Is it true that whale poop is partially responsible?
A: Yes! Whale poop plays a large role in the environment by helping to offset carbon in the atmosphere. When whales poop, they excrete a huge load of nutrients that are crucial to the ocean (We call them Poo-namis!). The surface of the ocean is fertilized with nutrients that are fundamental to maintain healthy ocean ecosystems, the carbon cycle, and the global nutrient cycle.
Q: Approximately how many whales are in the ocean today?
A: This is a very difficult question to answer! We would need to look at the population abundance of each species and that would mean that we would need to be in every part of every ocean in the world!
We do know the population abundance of certain species. The International Whaling Commission estimates that 382,595 blue whales were caught between 1868 and 1978. The global blue whale population abundance is estimated to be 10,000–25,000, roughly 3–11% of the population size estimated in 1911.
There are still over 1000 whales killed commercially each year by countries such as Japan, Iceland, and Norway. And, an estimated minimum of 300,000 whales are killed each year in nets and other fishing practices while others are killed by noise pollution, boat strikes and habitat loss.
Q: NASA recently asked you to participate in research surrounding how whales are good bio-indicators of climate change. Can you explain to us how we learn from them? Why look to whales as opposed to other marine mammals?
A: I have had discussions with NASA concerning how whales are incredible bio-indicators of climate change. Ultimately what happens to them will certainly happen to us humans! Whale populations may become extinct due to climate change and actually surpass deaths caused by habitat loss or overexploitation. The frightening thing is that this could possibly happen in the next few decades.
It is important to look at whales especially because they are affected directly due to migration patterns and feeding grounds at the Poles. Other species are important also since there are animals such as polar bears that may not have solid land to rest on due to melting ice.
Q: From your years of studying cetaceans, what is the most obvious sign of climate change in the oceans?
A: The most obvious signs are changes in arrival of different species in certain areas. The whales seem to arrive a little bit later and later every year in the Cook Islands. With melting glaciers and water temperatures changing in feeding grounds of humpback whales, the krill and herring that the humpbacks feed on have had to move from their areas. The amount of krill in the Antarctic has decreased by 70 to 80% since the 1970’s. That is at an alarming rate. Whales need to feed!!
Krill, which are tiny crustaceans, need sea ice and cold water for survival. Because of global warming and increased temperatures there is a reduction in the growth and abundance of plankton on which krill feed. The loss of sea ice removes the habitat that shelters both krill and the organisms they eat. Therefore, when Antarctic sea ice declines, the krill do also. Antarctic krill eat small plants like phytoplankton, as well as algae under the surface of sea ice.
Q: What are other obvious critical issues the oceans face?
A: I have noticed an increase of ocean plastic during my trips out on the water. It’s not just large pieces of plastic that I find or even the plastic bottles and jars, it is the tiny pieces of plastic that have broken down and have become known as micro-plastic. When I scoop into the ocean for bits of sloughed whale skin for genetic purposes, I often find tiny pieces of plastic in my scoopn net! It is heartbreaking to think that fish are eating the micro-plastic and we are eating the fish!
The rising of sea levels which threaten coastal population centers are also a concern. Air Pollution is responsible for almost one-third of the toxic contaminants and nutrients affecting coastal areas and oceans. Water pollution is also a problem. Factories and industrial plants discharging sewage and other runoff into rivers, streams and the ocean and pesticides and nutrients from agriculture ending up in the coastal waters, resulting in oxygen depletion. Did you know that U.S. water-sewage treatment plants discharge twice as much oil each year as tanker spills? This kills marine plants and shellfish.
Watch some of her incredible work with whales on her website here!