The Gift of Water:
Links between Land, Streams, the Sea, and You

Caroly Shumway
New England Aquarium

Introduction
This presentation is about the biological importance of water, how land, streams, and seas are connected, and how your daily habits and consumer choices affect aquatic life. This information will help you to know what you, as an individual member of society, can do to help conserve the wonders of underwater life. This document accompanies the Power Point Presentation by Dr. Caroly Shumway, listed on this website.

This is truly a water planet. Did you know that more than seventy percent of the earth’s surface is covered with water?

All life depends on water for survival. Our bodies consist of sixty-percent water. The properties of water that make it such a “life-giving element” include the fact that water is a universal solvent. Wherever water goes, either through the ground or within our bodies, it takes along valuable chemicals, minerals, and nutrients. It also has a neutral pH, a very high surface tension that allows capillary action by plants and bodies, and a high specific heat index, which helps to regulate climate.

Some Indicators of Human Impact
Although water is vital to life, too often we treat water, and the biological resources on which we depend, with indifference, or, worse yet, contempt. Humans are causing global changes to the environment, including species loss, habitat destruction, and most terrifying, changes to the biogeochemical cycles upon which all life depends.

For the first time in history, humans are affecting species and habits all over the globe, pushing many to the brink of extinction. Extinction rates are 100 to 1,000 times above background levels. This can be seen through species loss at various levels: twenty-five percent of all bird species are already extinct and twenty percent of freshwater fishes are threatened or endangered worldwide.

More than seventy percent of the planet’s land surface is fully or partially degraded by agriculture, natural resource use, or construction. The changes are only in part due to population increases. For example, even though the Rhode Island population has remained constant, the state has lost roughly half of its farm land over the past 20 years. Nearly 1,000 acres a week are lost to development in various parts of New England.

Human activity has also resulted in dramatic damage to the world’s oceans. Fifty “dead zones” (areas with little or no oxygen typically caused by excess nitrogen and phosphorus flowing via rivers into oceans) have developed in coastal waters. An estimated ten percent of coral reefs are already dead and seventy percent are at risk. Fifty percent of all mangrove habitats have been destroyed; and estuarine habitat is either destroyed or heavily polluted in many areas around the world. The effects of human pollution are also present in the ocean depths at the seasurface layer (where larval fishes live), the middle of the Pacific, and the deep sea.

Why Conserve Biodiversity?
We all live in an ecosystem, even city dwellers. Aquatic ecosystems provide essential and economically important ecosystem services that support human life such as: regulating climate; and cycling water, oxygen, carbon dioxide, and nutrients throughout the biosphere. A recent cost-benefit analysis conducted in New York City concluded it was cheaper to preserve the watersheds in upstate New York than to obtain water by any other means. Biological diversity also provides us with products for food, shelter, clothing, fuel, and medicine, contributing approximately $2.9 trillion annually in goods and services.

Why should we care about biodiversity conservation? There are very real scientific reasons why we should care about conserving biological diversity but personal reasons are perhaps most likely to motivate us to change our behaviors. Scientists, for example, begin their careers as young children, mucking about outside and exploring all kinds of animals and ecosystems. As a result, they became passionate about certain animals. These experiences often deeply effect their moral belief systems, creating a strong need to protect the species around them. Protecting aquatic systems and the biological diversity within those systems is both a moral and a spiritual issue. It is simply the right thing to do—for ourselves, for our children, and for the other life that shares this planet with us.

The Need for Scientists and the Faith Community to Work Together
Clearly, the efforts we have made in conservation are equivalent to rearranging the chairs on the Titanic. The problems we face lie not in managing other animals but in changing human behavior, for this is at the root of contemporary environmental degradation. Many environmentalists have tried to change behavior and attitude toward the environment through environmental education that focuses on the impact of human actions on ecosystems. Unfortunately, providing people with information does not necessarily change their behavior. Behavior is influenced not just by knowledge, but also by attitudes, values, gender, social norms, skills, economics, time, options, greed, laws, habit, and beliefs.

Somehow, we must change human hearts, minds, and actions toward the natural world. We must reawaken a sense of reverence and gratitude for nature, and inspire urgency in addressing environmental threats as we try to come to terms with the full extent of humanity’s impact on the environment. Collaborative efforts among scientists, conservationists, and the faith community can help us to achieve better environmental practices. We have much in common in our desire to protect the earth. In our own ways, and in our own words, we all share a sense that nature is sacred and worthy of protection; a place to renew the human spirit and refresh our emotional and mental health. If we are to protect the full diversity of life on this planet, we must all work together to restore a sense of the sacred in creation.

There are also practical steps that we need to take. How can we help move consumers from awareness to adoption of behaviors? Scientists can help by assisting the public in understanding basic ecological principles, connections between various habitats, and how the actions of individuals and societies are affecting biological diversity. Religious groups can help by advancing the notion that there is more to life than economic development. This has been shown in a recent study that concluded that those who accumulate more goods are not happier. The United Nations Development Programe (UNDP) “Human Development Report” indicates little correlation between economic development, as measured by gross domestic product (GDP), and the quality of life, as measured by health, literacy, crime rates, etc. When someone says, “It’s the economy, stupid,” quietly say, “No it’s not. It is about the quality of life, for us, our children, and the other living beings that share life with us on this planet.”

Land, Fresh Water, and the Sea are Connected
Water connects various ecosystems, yet most of us do not realize that all people, even those who do not live next to an ocean, have daily connections to freshwater and marine ecosystems. In addition to the importance of providing drinking water for humans and animals, the ecosystems on land, freshwater, and the sea are all connected through the movement of water and the movement of species throughout their life stages. These connections occur on two levels, through ecological processes and through human land-use practices (e.g., forestry, agriculture, and development).

Nutrient Flow
Rivers and streams move nutrients and minerals from watershed and lowland areas to the sea, and all of the points in between. For example, floodplains, found in the middle section of the United States are extraordinarily productive agricultural areas because the rivers transport organic material and sediments to the floodplain soil. Once transported, nutrient flow does not stop at habitat cycling. Flooding also releases terrestrial nutrients into the aquatic ecosystem thereby generating increased aquatic plant production and food for aquatic life (e.g., fish). This reciprocal nutrient movement is also seen at the species level. As species (e.g., salmon) swim from the sea to freshwater ecosystems they transport vital nutrients into the streams. The fish are then eaten by predatory mammals (e.g., bears) that transport minerals contained in the fish into adjacent forests. These nutrients then help to foster tree and plant growth. Salmon thus helps to provide an important, nutrient rich biomass for the forest ecosystems. Areas in the United States that have had large population of migrating salmon have had their ecosystems completely changed.

Species Movement
In aquatic ecosystems, one of the most important life-cycle movements of species is the movement of fishes from less saline waters (e.g., freshwater systems, riverine ecosystems, lake systems, etc.) to the sea. Several commercially important marine fishes and some coral reef fishes live in less saline ecosystems (e.g., estuaries and mangroves) in earlier life-stages and move to saltwater ecosystems (e.g., the sea) later in life. The less saline nursery areas provide both food and shelter to the developing young, as well as rich feeding grounds for a variety of different species.

In terrestrial ecosystems, life cycle movements also effect mammalian migratory patterns. A number of African wildlife populations base their migration patterns around the production of floodplain grasses. The distribution of some floodplain tree species depend on animals (e.g., hippos) to eat the seeds in order to enhance the germination of the seeds and to aid in species dispersion.

Aquatic flow also affects species migration in riverine, arid, and semi-arid ecosystems. For example, like the vernal pools of the southwestern United States, there are several arid and semi-arid areas in Africa that contain ephemeral rivers or streams that flow for short durations (e.g., a few weeks during the rainy season). Ephemeral rivers and vernal pools, essential to terrestrial wildlife, make up a diverse and globally unique desert ecosystem. Rivers in these systems transport organic material and sediments to the desert, causing both the germination and recruitment of riparian vegetation as well as recharging groundwater systems.

Food Webs
Habitats next to rivers provide nutrients to rivers and streams through the dispersion of leaves, fruits, seeds, flowers, and branches into aquatic ecosystems. A number of freshwater fishes and invertebrates depend on this terrestrial plant material for shelter and food.

In the United States, insects are something we spend a great deal of effort trying to eradicate. Yet if you care about frogs or birds, you can appreciate that while we need to address insects as pests, we also need to try maintain some insects in order to keep certain species alive. It is important to remember that twenty percent of threatened insect species have aquatic larval stages and that these species are food sources for other species. Their decline threatens aquatic and terrestrial species that feed on the insects at different stages of their life cycle.

A close interconnection exists between aquatic ecosystems and terrestrial species. This can be seen by examining the effect of polychlorinated biphenyls (PCB’s) on forest birds in the Hudson River valley. Birds in these areas feed on insects that have aquatic larval stages. Thus PCBs in the river have a direct impact on the bird population in that area.

It is important to realize that aquatic ecosystems are more difficult to protect than terrestrial ecosystems because they depend on the quality and quantity of the water present. Both of these factors can be affected at every stage of transport (e.g., from the pathway between a water catchment and the given system in which it is delivered). Coastal lagoons, estuaries, mangroves, and deltas all rely on an adequate freshwater levels in order to ensure the perpetuation of various species within the ecosystem. For example, freshwater runoff to the sea is an important contributing factor to the well being of various marine species. Without enough freshwater, the temperature and salinity of the ocean can increase while oxygen present in the water decreases. An imbalance within the system can potentially insight a high rate of fish mortality. Additionally, the health and well being of an estuarine ecosystem (e.g., high productivity and species diversity) depends on the delivery of upstream nutrients, organic material, and sediment. Finally, freshwater flooding can benefit coastal ecosystems by increasing nutrient availability, from upstream mineral deposits to the physical mixing of the floodwaters into the ocean that cycles the deep level nutrient-rich waters into the shallower water zones. This dependence on the quality and quantity of water makes aquatic ecosystems more vulnerable than terrestrial ecosystems to the effects of land-use activities beyond their boundaries. The implications here are not just for run-off waters but also for underground water and even entire watershed systems.

We are Connected to Aquatic Life Near and Far through Our Consumer Habits and Practices
Wood
What does the wood you buy have to do with aquatic life in the South Pacific? The deforestation that is taking place in Papua New Guinea and the Solomon Islands is driven by Western consumer demand. Unsound forestry practices lead to heavy soil runoff that results in increased sedimentation release to coastal aquatic ecosystems. These increases in sedimentation have a direct impact on both terrestrial and aquatic species. Corals, and their symbiotic zooxanthellae, require clear water to survive. The release of sedimentation into coastal aquatic systems through the deforestation process can prevent coral settlement, affect reproduction, and kill the coral reef itself. In streams, sedimentation through deforestation destroys the fishes’ terrestrial sources of food and degrades habitat. In the United States, scientists have found that the deforestation along the Columbia River banks is inversely related to the number of freshwater mollusk species in its tributaries. In other words, where sedimentation due to deforestation has occurred, a number of species are now extinct. Studies have shown that in places where the forest system was maintained, species diversity and population are much higher. Therefore, sustainable forestry practices can reduce the damage to aquatic systems at various levels.

Food and Clothing: The Use of Chemicals and Chemical Effects on Frog Populations
Commercial farming, with its heavy emphasis on fertilizers and pesticides, affects both terrestrial and aquatic species. Audobon Society Magazine estimates that 60 million birds and 9 million fish die annually in the United States due to pesticide use. Frogs, too, with their sensitive embryos and permeable skin, have been directly affected by direct or indirect chemical release into aquatic systems. Their eggs and tadpoles are particularly susceptible to the effects of pesticides.

Major Threats to Aquatic Biodiversity
Pork, Estuaries, and Sea Turtles
Large, industrial-scale farming practices such as pig farms are a tremendous problem to aquatic ecosystems because feces and waste from these farms ends up in estuaries and wetlands, thereby causing eutrophication (extra nutrients leading to algal blooms) and dead zones (areas with no oxygen) in aquatic ecosystems. In addition, industrial farming uses sargassum as a cheap additive. The depletion of sargassum, a floating algae, affects an essential habitat, not just for endangered turtles but also for 200 other species. Sargassum serves an integral part of the juvenile turtle’s life cycle. At least four sea turtle species use sargassum as a floating and transportation device during the juvenile migration stage.

Artificial Lighting and Sea Turtles
Artificial coastal lights also disrupt aquatic life by disorienting nocturnal aquatic species and altering their swimming patterns, migrations, and reproductive behavior. More than one million migrating hatchling turtles die annually in Florida because their instinctive rush to the sea is deterred by their attraction to artificial coastal light systems. Experiments have revealed that some species, such as the loggerhead hatchlings, have an avoidance response to yellow light. This information has been utilized to identify lights that do not affect turtle migration. Thus, knowledge of turtle sensory physiology can help us manage light pollution more effectively.

Driving Forces Threatening Aquatic Life
The root causes of biodiversity loss are the same on land and water: overpopulation and overconsumption (by individuals, corporations, and societies). While all living things must consume, what is at issue are wasteful and pointless consumption and greed, inefficient practices, resulting effects of pollution and waste, a lack of knowledge regarding the effects of the loss of biological diversity in their area, and a lack of appreciation of our own integral dependence on the natural world for our mental and physical health and survival. While our economies depend on biological resources, most economists still do not adequately value ecosystem services and natural capital.

What can we as a society do to help stabilize aquatic biodiversity?
There are several things that we can do.

What Can You Do To Save Aquatic Biodiversity?
People must become educated about and concerned for the quality of biological diversity that exists on this planet. They must begin to see biological diversity as a priceless entity. Biological diversity should be reframed as an issue, making the preservation of species a patriotic expression of one’s concern for country. Everyone has the right to a clean and beautiful environment.

We all need to care about the life around us. We need to appreciate that humans and human created ecosystems (e.g., cities) are a part of nature. We must strive to preserve biological diversity where ever it occurs (e.g., cities, parks, suburbs, deserts, meadows, forests, rivers, estuaries, and oceans). We also need to link environmental and social justice efforts by improving social and environmental standards in even the poorest of neighborhoods.

Individual changes can make a huge difference. For example, many people have chosen to purchase organically grown foods. Over the past ten years, consumer demand for organic fruits and vegetables has risen at an annual rate of twenty percent. By choosing organic foods, consumers have postitively effected the aquatic environment through the reduction of harmful pesticides, herbicides, and fertilizer run-off. Thus, as individual consumers, people can help to guide farmers in the marketplace to utilize more responsible environmental practices that protect biological diversity.

Another important thing people can do is to speak out. Be the child in The Emperor’s New Clothes by telling others about the absurdity of our current economic assumptions. Do not be afraid to mention that our current assumptions ignore the finiteness of this planet and its resources. Speak out on the futility of our manic quest for happiness in material things. As a recent commercial notes, “There are some things that money can’t buy.”

All rights to this material are reserved.
Copyright © 2000 Caroly Shumway and the New England Aquarium.
Reprinted with permission.