Friday, August 21, 2020

Non-native Species Invasions

One of the most challenging scenarios of the invasive species phenomenon in the US is the heroic battle officials are waging to deter the entrance of Asian carp into the Great Lakes. These Asian imports, silver, bighead, black and grass carp were deliberately brought to the US by operators of aquaculture ponds and aquatic farms in the southern US in the 1970s. Their purpose was to control algae, weeds, and parasites in the farmed ponds. Tragically, during flooding events the fish accidentally escaped into natural river systems. Over several decades they have established a relentless northward migration within the Mississippi River drainage basin. Their colonization of the Great Lakes would constitute an environmental disaster.      

Many preventive regulations and millions of dollars have been spent on physical, electronic, sonic, and other means within the Chicago Sanitary Ship Canal (CSSC) and other access routes to Lake Michigan. So far, experts hope their vigilance may have achieved the desired goals, but the battle is far from won. Invasive carp species in the US do not cope with the sort of predators they encountered in their native land—a fact we could repeat for many other recently arrived invasive species.

As God’s people we must be aware of causes and effects with respect to environmental issues. In the sphere of our physical environment we benefit not only from intended consequences of our actions, but also from unintended consequences. Undesirable unintended consequences result from lack of knowledge. The OT prophet Hosea (Hosea 4:6) was concerned about the lack of knowledge among the chosen people in their relationship to God. “My people shall perish from lack of knowledge,” the prophet exclaimed. More broadly, knowledge is a desirable treasure in every sphere of physical existence. 

Problems with invasive species are often of human creation. An invasive species in America since 1831 is the European, or “common” carp. Late in the 19th century the United States Fish Commission distributed European carp widely across the land as a food source. Culturally, carp are shunned by many US residents as a food product, but in many other countries carp as a food source is accepted. Carp are now ubiquitous across the US, accepted as a fact of life.
Many people enamored by the sport of fishing are not concerned about whether their “catch” is native, non-native, or even invasive. To young people, especially, these distinctions mean little. They love to catch fish—especially large fish! We illustrate by both personal and historic accounts.

The Seneca River drains the famous glacial Finger Lakes of Central New York State, eventually flowing into Lake Ontario. The Seneca flows through Baldwinsville, my birthplace, home of the NY State barge canal. Downstream from the canal locks in Baldwinsville, the river is home to a plenteous population of European carp. All European carp in the US are non-native, including all Seneca River specimens. Therefore, the Seneca River did not provide carp fishing before the introduction of non-native “common” or “European” carp to the US in 1831. We muse about a visit to the Seneca River in 1830.

Our story relates to a national event scheduled for 2022—the “world series” of carp fishing in the Seneca River and nearby Onondaga Lake. Since 2007 Baldwinsville has been the home of the Wild Carp Classic, a famous carp fishing tournament held annually. My brother called my attention to the carp tournament held in my former hometown about ten years ago. The Google search engine has dozens of references to the fame of Seneca River carp. My personal recollections of carp fishing are many: fishing for carp with balled-up white bread pieces, snag fishing from the Niagara-Mohawk Power Plant concrete wall with treble hooks in deep water where one carp nearly pulled me into the river, and other experiences too numerous to recount.

Other ecological nightmares have occurred involving bluegills, a staple of pan fishing enthusiasts, and lake trout, a favorite of deep fresh water anglers. Both species are native to North America. A front page article from a local daily newspaper in Dubuque, IA, May 20, 2020 retells a familiar invasive species story. Proof of the fact that invasive species affect other countries beside New World nations, Japan now has invasive bluegills inhabiting their ecosystems. Bluegills also now inhabit Korea.

In 1960 Mayor Richard Daley of Chicago presented a collection of 15 bluegills to Emperor Akihito of Japan on a visit to Chicago. The emperor envisioned bluegills as an important food source. Instead, descendents of these bluegills have wreaked ecological havoc in Japan’s waterways. Genetic tests have established that all Japanese bluegills originated in one location near Guttenberg, IA. Japanese scientists entered the US in 2002 to carry out sophisticated genetic tests on fish from many different waterways in Iowa. As a result of these tests, the origin of millions of Japanese invasive bluegills was traced to just one location in Iowa—only 15 fish!

Many different fish species can be classified as invasive, causing ecological or economic harm in a new environment where they are not native. There is sometimes a delicate ecological balance among different species of trout. Fascinating stories of introductions in a place where specific species are non-native, and the staggering costs of remediating the damage caused, create fascinating tales.         

The lake trout introduced to Yellowstone Lake in Yellowstone National Park threatened to displace or reduce a famous trout species prized by anglers and depended upon by grizzly bears and birds of prey. Cutthroat trout are a famous, ecologically important species in Yellowstone Park. Non-native lake trout were deliberately or accidentally introduced displacing or severely reducing the population of cutthroat trout. Many iconic creatures for which Yellowstone is famous were impacted. Since 1994, 3.4 million lake trout were removed from Yellowstone by gill netting, reducing their population by 73% since 2011. The gradual return of cutthroats to Yellowstone Lake and its tributaries continues—an invasive species remediation success story.

Environmental alterations triggered by humanity fall along a spectrum. Some changes are beneficial; some are harmful. Our Creator has bestowed freedom for mankind to manage the environment. God provides wisdom to manage wisely as well as wisdom to avoid and remediate errors. We thank Him for the gift of freedom.  


Thursday, August 13, 2020

Invasives, Non-natives, and Ecosystems

The rapid rise of human population has brought with it an explosion of new concerns for humanity. World population first reached one billion in 1804. On a graphic scale we had a roughly linear population for many thousands of years. Since 1804 the graph of human population has resembled an exponential growth curve. World population since 1950 has more than tripled from 2.5 billion to 7.8 billion. The problems for our environment, especially related to invasive species, have been monumental. 

How are invasive species related to healthy ecosystems? Invasive species are not indigenous and are deliberately or accidentally introduced from a different region, often a different continent. By definition, invasive species cause harm to the environment in various ways. Examples are numerous. Invasive species displace native organisms and reduce healthy biodiversity, often propagating at a rapid rate. Humans have introduced non-native, invasive organisms for a variety of reasons. Many invasive organisms arrived unintentionally. One example: early settlers in the New World longed for plants and wildlife typical of their native homelands. They were not cognizant of ecological impacts and many invasives damaged or disrupted their New World environment. Consider the European starling, the English sparrow, the gypsy moth, kudzu vine, and the ubiquitous garlic mustard and wild (poison) parsnip, to name a few.  

The USGS (United States Geological Survey), a scientific agency of the US government, states, “More than 6,500 non-indiginous species are now established in the United States, posing risks to native plants, animals, microorganisms, valued ecosystems, and human and wildlife health. In fact, the current annual environmental, economic, and health-related costs of invasive species exceed those of all other natural disasters combined.” (emphasis mine) The US Fish and Wildlife Service reports 50,000 non-native species exist in the US. 

We contrast another aspect of invasive vs non-native species. Some non-native species do not necessarily result in environmental harm and are not, therefore, termed invasive even though they may have been deliberately or accidentally introduced in a new geographic region. Such non-native species could be beneficial from an environmental, economic, aesthetic, or resource-providing standpoint. Examples are most cattle and farm animals used for food and other products in North America. Imagine our modern society without the contemporary food benefits of beef cattle or poultry. Many familiar animals trace their origins to the Old World. Likewise, a large fraction of fruits such as apples, peaches, pears, and apricots are not native to the Americas. Moreover, much food consumed by cattle, poultry, and humans in our society comes from soybeans and wheat—non-native imports from the Old World. 

In the world of plants and animals, native signifies the region of their original habitat. Many plants have been introduced from the Old World, or from distant geographical sections of the New World. ‘Native’ has acquired a positive connotation while the term non-native may be regarded with some suspicion. Invasive species are justifiably regarded with the most disapproval.

Our post concludes with mention of ecology, defined as a branch of biology dealing with the relationship of all organisms in an environment with each other and to the environment. In the pristine New World discovered by the Norse explorers and later, Christopher Columbus and other Europeans, continents generally possessed a pleasing “ecological balance.”

A WWF (World Wildlife Fund) article defines ecological balance as “a state of dynamic equilibrium within a community of organisms in which genetic, species, and ecosystem diversity remain relatively stable, subject to gradual changes through natural succession.” Their definition concludes with praise for “a stable balance in the numbers of each species in an ecosystem.”

The physical creation with its array of physical constants was divinely fine-tuned long before life appeared on the planet. When life, especially human life, was created, fine-tuning became even more exquisite. We suggest that ecological balance was in the mind of God as a feature of divine fine-tuning. The divine mandate to humans to manage their environment responsibly involves achieving ecological balance to every degree possible. Human life, the crowning achievement of the Creator, was granted the highest thinking capacity and ability. God has gifted humanity with the ability to manage environmental conditions in satisfying and responsible ways. Humans are able to comprehend environmental issues and benefit from understanding the concepts of ecological balance. 



Saturday, August 1, 2020

Invasive Species Nightmare

While researching the topic of invasive species we may be overcome with the overwhelming complexity of the topic. For the most part ‘invasions’ possess unpleasant overtones. Invasions are usually unwelcome, be they military incursions, or the arrival of objectionable biological entities. Plants or animals not indigenous or native to our area could bring with them unwelcome environmental changes or damage. Included in the latter category are also pathogens such as bacteria, viruses, or fungi. Some invasive species apparently do not cause environmental damage. We perceive them, incorrectly, as native species. Such pathogens have arrived from afar, even from a foreign country. These undesirable arrivals may also be termed “exotic.”

Invasive species in the Americas are far more common than we realize. Research into species categorized as invasive reveals hundreds of organisms—plants, animals, and pathogens which were known not to be native to this hemisphere before the arrival of explorers from the old world. The New World, North and South America, would be virtually biologically unrecognizable were we to board a time machine and visit the Americas of Columbus’ time only 500-600 years distant, or Norse settlements about 500 years before that. Native American Indians inhabited a land biologically different in many ways. We recall the Native American experience on our continents hundreds of years ago with great fascination. The fascination is historical, political and biological.

We reference our personal experience in Northern New Jersey after the family moved from Central New York State in 1951. In 1904, the unique eastern American Chestnut forests became infected by a fungal disease which originated in East Africa—the “greatest ecological disaster in our forests.” After a half century the American Chestnut forests which frequently produced gigantic trees over 100 feet tall in Eastern US were nearly gone—three billion trees. Our home in New Jersey, built in 1926, retained much wood in its bookshelves and decorative wooden pillars. They were constructed from wood of the American chestnut.

Our family left behind a heritage of agricultural beauty on its way to Northern New Jersey. A mighty elm had overlooked our farm fields in Onondaga County, NY, where we harvested corn, wheat and oats. The majestic elm has since yielded to an invasive species—the dutch elm disease. In our current home in northwest Illinois, we contracted for removal of over a dozen “expired” elm trees—victims of the same dutch elm disease. As I write, another elm across the street from our home awaits its final demise. Elm bark beetles are the vector for spreading the fungus which kills many majestic elm species. Dutch elm disease appeared in the US in 1928. It was also an exotic ‘wilt’ fungus, an import from the Old World. Forty million elm trees have perished in the US—many more around the world.

Ash borer, an insect native to NE Asia whose larvae feed on the bark of ash trees, currently infests many of our local trees. It entered the ecosystem in 2002 in Detroit, MI, on wooden packing materials from China. The borer damages the tree’s ability to transport water. Dieback and bark splitting results. 

Another personal experience with an invasive plant must be told, this time a harmless plant. In the last decade of my teaching career my students and I discovered a single, unusual woody plant in an unlikely forest location during a school sponsored trail hike. We returned to school with several huge leaves. One YouTube clip claims the leaves of paulownia tomentosa produced by the shoots of a tree cut down to ground level are as big as a car wheel. Pictures show gigantic leaves over two feet in diameter. The plant is known to consume enormous quantities of CO2. It is a prolific exotic from China which first arrived about 1840. Tongue in cheek, our students speculated the plant may have been a rare mutation from another planet.

More often than not, invasive species are deleterious. Most locales in our area are plagued with many invasive weeds and plants. Poison parsnip and garlic mustard are two common examples. There are many other illustrations.

The frequently quoted Genesis 1:28 contains an exhortation to ‘subdue’ the Earth. We  carefully interpret the meaning of ‘subdue’ in the context of responsible environmental practice. Humanity has an obligation to study diverse characteristics of multiple species within their ecological niches. We must carefully avoid importing harmful invasive species, either deliberately or accidentally. Humanity’s record in this area has been deficient.

Our research of this topic from a personal perspective has inspired us to study the invasive species issue from a more global perspective.