Usha Varanasi is Director of the Northwest Fisheries Science Center in Seattle, Washington, which is part of the NOAA Fisheries Service. Dr. Varanasi has held this position since 1994, when she became the first woman to lead one of the Fisheries Science Centers. Dr. Varanasi spoke with Earth & Sky's Jorge Salazar about her work in studying the ecosystem of Puget Sound.
|Dr. Usha Varanasi|
Salazar: Thanks for speaking with me today, Dr. Varanasi. Could you describe some of the work that you and your Center are doing, in and around Puget Sound?
Varanasi: Estuaries like Puget Sound are where river freshwater and salt water mix. From there, they connect to the ocean. So when we say that we study the fish in the ocean, really we study them from their origin, from "white water" or the snow in the mountains, to the blue water in the deep ocean. We study the species that travel that way.
And we look at all the stress that people or our activities may be causing to the health or survival of a species. We also consider natural causes, like climate change, storms, or volcanoes. So the natural risk factors are superimposed on the risks that we humans pose to the species. And that gives us an idea of how to reduce the risks.
We cannot reduce all of the risks, because we cannot control the weather, and we cannot control some of the changes to Earth. But we can educate people, and we can make policy-makers understand that some of the factors, such as pollution. For example, when there is algae blooming in estuaries, or in the ocean, sometimes it is converted into toxic products, which can make the seafood that we consume very dangerous for human health. But these toxic products also affect the health of creatures living in the water.
And so we study both sides of the picture. We study how humans may be affecting the health of the ocean. And we study how, when the health of the ocean changes, that affects us by swimming in there and eating the seafood.
Once we know the risks, we can actually put some numbers on it. Then we can provide options to the managers who make decisions about regulating some of the standards of wastewater, or fishing permits, or all kinds of human activities taking place on our waters.
Salazar: Can you give me some historical insight into what has made the Puget Sound what it is today?
Varanasi: When we love somebody or something, sometimes we don't realize that we may overuse it. We humans love water. We love coastal areas, and we gravitate towards living very close to water. We like to use many parts of the system. We use wildlife in the ocean for our food. The fish and shellfish is a huge portion of the protein that human beings take in and need. In many parts of the world, that is the major source of protein.
In the late 1970s, people started to realize that fish were as susceptible to the pollution from oil spills as human beings could be. We started to see some of the cancers in fish, for example, liver tumors. And in the late 70s and early 80s, we had many, many sites where we used to sample the water in Puget Sound. We still sample quite a lot. And we were able to identify areas where there was quite a lot of discharge from industry, of toxic chemicals. That is called point-source pollution. You could actually pinpoint where the chemical contaminants are being released. For the sewage treatment, they have tertiary sewage treatment, which is rather sophisticated, compared to some areas in the U.S. where raw sewage is practically discharged. In Puget Sound, there are many measures of making sure that raw sewage is properly treated.
There has been a considerable improvement in the incidence of cancers and so on in fish, especially in fish that lived at the bottom of Puget Sound. But people all love the Sound, want to be on the water, want to use it. And now individual contribution to pollution has increased tremendously. This is called non-point source pollution, where we can't identify a major source and therefore can't put many protections. Now everybody has to realize that every time we dump something in the sink, or use fertilizers, or use chemicals in our plants and our lawns, some portion is eventually going to end up in our water. That is one reason why we are beginning to see, again, changes in profiles of contaminants in Puget Sound.
The other thing that has changed in Puget Sound is that we have more boat traffic. We have more big ship traffic, because we are a very active port. We have tourist ships coming in. So I think that another source of pollution increased because ballast water, which is removed from the ships, can have bacteria, viruses, and some of the parasites that can be deposited into our waters.
Since 1991, we have been seeing more incidents of algae blooms. Sometimes they become toxic, and we are trying to understand what makes them become toxic because, on the west coast, we are finding that those incidences are becoming more prevalent. And, sometimes I think the El Nino may be triggering it. But we also use a lot of agricultural pesticides and fertilizers, and those all together can trigger a production of algae, and sometimes those algal blooms can become toxic. We are leading a large program to monitor these kinds of algal blooms, and forecast their movement, so that fisheries and shellfish can be protected, and so that people don't harvest some of those shellfish during a period when the fish have become contaminated.
Salazar: How can you measure the level of success in monitoring the Puget Sound ecosystem?
Varanasi: The question is, how does one measure the health of an ecosystem when that ecosystem is diverse as Puget Sound? There are several different ways of doing it, and this is why this particular report that comes out once a year called the Puget Sound Ambient Monitoring Program that has indicators, and some indicators and some trends are positive, in those chemicals that I was saying, PCBs, are declining in the sediments of Puget Sound. But flame-retardants are increasing.
I cannot tell you in one sentence whether it is getting better or worse. That is very hard to do. We have reduced the sources of pollution that were easily managed, such as industry and sources of pollution that came from an end of a pipe. But, over the years, we have actually increased non-point source pollution. I would say that, from the standpoint of non-point source pollution, the condition of Puget Sound is declining. We have now more areas with low, but insidiously growing levels of contaminants. We have not reached a "red zone," so to speak. But we are inching toward that.
One of my concerns has always been that people's attention is always on super hot areas. We always are concentrated on trying to do something where there is a terrible effect. And, of course we should do it. But we don't keep an eye on large areas that, if we spent a little amount of money, we could keep them going right.
One very positive thing happening in Puget Sound is that, because a number of the salmon species there are listed on the Endangered Species Act, there is a considerable movement to restore watersheds and habitat. There is a considerable movement to improve water quality. We are becoming more aware of tools that we can use.
So I gave you a long answer because there is no short answer. If there were a short answer, it might be that, while we are better at controlling some of the major sources of input at the point source, we actually have more small levels of pollution coming in from many parts Puget Sound. Because of this, Puget Sound may become contaminated overall.
Salazar: Dr. Varanasi, thank you for your time.