The Insect Problem By Courtney Watson
Insects can be a rather invigorating nuisance to many people. Constantly getting in our faces, biting, spreading diseases, being attracted to the slightest bit of food or smell, they swarm our pets and farm animals, and food that is grown; they’re just everywhere. To some people, bugs are bugs and it doesn’t matter what they are. To them a bug is a bug. They don’t separate them out into different categories such as in the case for this paper: Pests and pollinators. While the world is full of insects that take from our lives, we are also blessed with insects that help provide for our lives.
In order to manage insects, for better or worse, people must consider taking time to truly understand them. For the purpose of this paper I will be taking two approaches focusing on the economic and environmental impacts of insects with a deeper look into the positive and negative impacts they create on the environment and the economy with most of the focus being on the United States. Solutions for management within the scopes of interest will also be briefly discussed.
Insects can be traced back with fossil records to the Devonian era which was approximately 441 million years ago (Engel 2015). They were around with the dinosaurs, and are very successful critters that continued to evolve after mass extinctions (Engel 2015). With millions of species existing today, insects outnumber the human race by a considerable amount. People love them, despise them or ignore their presence. Insects are so diverse that most species are in constant state of flux for getting permanently placed onto the tree of life. They a generally categorized by physical characteristics such as segments of the body and appendages of varying types, and wings (which are an evolutionary trait) (Engel 2015).
When flowering plants came about, the youngest of all plant species, insects continued to diversify and created pathways for many flying insects and pollinators. Insects are still continuing to evolve over time and it should be said that if there was to be another mass extinction in the future, insects would likely still continue to evolve in awe-inspiring ways to continue their survival.
Introduced insects have been a problem since for as long as anyone can remember. Most managed to find their way here by the transport of goods across the sea or they were brought here on purpose and released into the wild. With global warming continuing to increase at rapid rates, many pest insects are becoming more abundant. The lack of frosted weather and freezing temperatures is creating increased growth rates and reproduction of pest insects (Bale et al. 2002). It is described briefly by a few sources that warming temperatures also cause insects to be able to start dispersing to many different places much earlier than normal (Woidwod et al. 1997, 1994, Zhou et al., 1995, Fleming et al. 1995). Overall, insects in general are shifting out of their original range distributions to find more comfortable climates, many are continuing to disperse north to achieve this goal (Cayan et al. 2008). Climate change and chemical use either create more damage or don’t do enough because many are becoming more tolerant to chemicals while the ones we actually need are suffering.
Our improved agricultural practices here in the U.S. over the past many years has contributed to the growth of our economy (Dimitri et al. 2005). While there have been multiple ways of influencing our agriculture in this country everything comes down to the most important thing in agriculture, the products that we raise: crops and animals. There are quite a few insects that as an individual species alone, can cause billions of dollars in crop damage and loss in the United States.
The list of destructive insects is rather exhaustive when it comes to economics and the environment. Each year about 13% of produced crops are destroyed with an approximate total of 13 billion dollars each year out of the 33 billion that are produced (USBC 2001). Various major and popular species will be discussed throughout this paper.
Back in 2013, USA Today posted an article about invasive pest species. One insect, known as the Asian Citrus Psyllid, caused about 4.5 billion dollars in damages to oranges and grapefruits in Florida all on its own. This insect feeds on the leaves and stems of citrus plants and are also known to aid in the spreading of a plant disease known as citrus greening disease (CDFA 2016). Much research has defined many pest species as invasive because they were imported from mainly Europe and other parts of the world through exporting goods. Non-native species have been found to adapt quickly and survive well in new areas, and it causes a problem in many parts of the world, especially here in the United States.
In continuation with crop dissemination, a few popular candidates that most people are familiar with are moth larvae and aphids. The Diamondback moth contributes to about 4-5 billion dollars in destruction in the United States by stunting growth of young plants and creating holes in many types of other crops (Zalucki et al. 2012, UC IPM 2016), essentially making the crops un-usable and non-profitable. There are many more varieties of moth species (grapevine moths, codling moths, etc.) whose larvae commonly feed upon all parts of fruit trees causing rot or death (USA TODAY 2013).
Aphids are tiny insects that suck out fluids from plants and dry them out. They often accumulate quickly on plants if they are not managed immediately in any environment. They too also spread diseases to other plants. Found worldwide, some species are known to be able to take down large areas of forests causing problems for birds that nest in trees.
Another costly insect is the termite, one of the earliest formed cooperative, social societies and created in the past (Engel 2015). They are found worldwide and are invasive in many places, but not all species of termite cause damage. Many do cause problems for crops, and many are famous for colonizing in homes and causing structural damage to any wood that is present. The Formosan termite can create at least 1 billion dollars in damage a year in the United States, especially in very wet areas, such as areas in the south (Corn et al. 1999).
Many non-native and invasive species of insects are also commonly found throughout the agriculture industry and in our forests, however there are some that are more adapted to forested areas such as gypsy moths, fire ants, and some beetles. The gypsy moth is a species that is commonly found along the eastern coast of the United States; creating silk tents as larvae on numerous amounts of trees, causing major defoliation problems across many tree species, especially with oaks (USA TODAY, Campbell et al. 1994).
Beetles are one of the most primitive types of insects and make up the majority known insects. There are some that are specialized pollinators to certain plants, some that aid in pest control and others that cause harm to plants. The native bark beetles have recently had major jumps in population numbers, causing mass die offs for trees such as the Douglas-fir; which in some areas it has been believed that because of these die-offs fire potentials in forests could be changed (Donato et al. 2013). The Asian Longhorned bark beetle is another destroyer of trees, specifically hardwood trees by burrowing into wood creating large holes where larvae will live and feed on living tree tissues. It is easily one of the most damaging beetles, costing billions dollars due unknown ways of being able to get rid of them (APHIS 2016).
Insects that aid in managing other insects is a major and natural benefit for the environment and agriculture. Lady bug beetles and green lacewings, for example, specialize in usually eating aphids and mites. The praying mantis is not a pollinator but it is a very skilled hunter and master of disguise and eats just about anything it can grab onto; as do assassin bugs, and ground beetles to name a few. Birds are another wonderful and natural source of aid in pest management as well. Birds are known to eat a wide variety insects such as caterpillars, beetles.
Crops are not the only thing that are affected by insects; animals are highly affected as well, both domestic and wild animals. A couple of examples in this situation are flies, and ants. In agriculture flies that are found are typically fruit flies; feasting on numerous fruits, vegetables or nuts depending on the species of fly. Flies are all typically considered irritating because they are attracted to food products and to body excretions such as sweat and waste. Many spread diseases and infections through biting and by simply touching food or they just leave painful sores (Keiding 1986).
There are quite a few red fire ants that are invasive species that were accidentally introduced into the U.S around 1918. These ants are highly aggressive with highly painful bites and stings. Many are very well adapted to being able to live in disturbed habitats. Fire ants are known to damage lawns, gardens, structural and electrical damage, remove seeds from crops while also damaging roots, attack young, weak, wounded and slow animals that can’t help defend themselves, other important insects and the list goes on (Vinson 1997).
The overall negative economic costs of pest insects is unfathomable. Due to the amount of great risks people take with insects, the majority of people are forced to resort to ways of managing pest populations to protect their plants, animals and even their homes. Chemical usage is an effective way to get rid of pest insects and keep them at bay, but even then it is just as costly to use effective chemicals.
Managing pest species is one of the most difficult things to do these days. It is usually a costly experience and often ends in harm for other important insects and even other types of predators. The use of various chemicals to spray crops and garden plants is a common technique to prevent insect infestations. Back in the 1990’s about 2.5-3 million tons of pesticides were used at a varying cost of 20-40 million dollars worldwide, without including application costs alone and half a million tons at 4.1 billion dollars were used in the U.S (Pimentel et al. 1992). There are many pests that are becoming pesticide resistant, leading to bigger problems and different types of new chemical usage.
There is more to the insect world than pest insects. People and the environment are heavily reliant on pollinator insects in order for plants to keep growing, reproducing and being used as food sources for all forms of life. These are our beneficial insects such as bees, butterflies and moths. About 80% of wild plants are dependent on our insect pollinators because many need either many or a single insect in order to keep reproducing (Ashman et al. 2004), while 75% of food crops rely in the pollination of insects as well (Klein et al. 2007). In 2005 180,093,240,000.00 billion dollars was the global annual economic value for insect pollination (Gallai et al. 2009).
For some time now bee species have been considered the most important pollinator. This includes honey bees and numerous amounts of wild bees. Bees aid in producing a wide variety of fruits and pollinating thousands of different native plant species and agricultural crops all around the world. For bumblebees, it was estimated that they contribute to 3 billion dollars a year in the U.S on pollinating crops (Losey and Vaughan 2006) and pollinate 75% of heavily reliant foods across the globe. In contrast to the benefits bees provide for growth, without bee pollination.
Unfortunately, the majority of most bees, especially wild bees, are suffering from heavy population decline from multiple direct and indirect threats, many being anthropogenic or human caused threats. There is a compilation of direct and indirect threats to bees and these are some of the main ones: pesticide use, habitat loss and disease contraction affect these vital pollinators heavily (Schweitzer et al. 2012). With these losses, crop and plant productions are being slowed and creating stressors for producers and consumers within agriculture.
Butterflies and moths are not at the same level of pollination importance as bees are but they still play a pivotal role in the adult stages of their life. Out of the many pollinator species butterflies are one of the most affected by climate change because their distribution ranges are changing drastically at community levels (Hickling et al. 2006). In 2015 the United Nations reported that 9% of butterflies are in decline with their populations (TIME 2017).
Butterflies and moths are very popular models when it comes to the environment and research because they are very attractive insects in the eyes of humans. At the environmental scale both of these insects are very important indicators for if an environment or an ecosystem is healthy, aid in indicating that an area is also well populated with other types of invertebrates. They are a common food source for a portion of the animal kingdom, especially when they are in the caterpillar stage.
The economic standpoint for butterflies and moths leans more towards them being a travel attraction for people (Monarchs in Mexico for example) and their development of chemical compositions within most species to deter predators, parasites and having the ability to feed on some toxic plants, leading to economic values more than of major agricultural importance (Butterfly conservation 2016). Unfortunately caterpillars of moths and butterflies are a common plants pest, eating their way through as much vegetation as possible every day before reaching the final stages of their life, destroying gardens, agricultural fields and even trees in forests.
Insect pollinators share many types of the same major threats such as pesticide poisoning, habitat loss, disease and climate change. There are many management and conservation solutions in place for pollinators. The U.S Fish & Wildlife service provides some ways to help aid these insects: planting native flowers in gardens, avoid pesticides or use chemical free methods for removing pest insects or even building homemade nesting sites. These methods not only help attract important pollinators but also provide a safe haven to forage and live within.
It is highly recommended by many government, like the EPA and environmental groups that, if you can, use chemical pesticides as a last resort and try these recommendations: removed any sources such as food, water or shelter to avoid attraction, block or close-off access points where pests can accumulate, store food items in sealed containers and remove any cluttered areas to prevent hiding places and avoid possible moisture build ups. If one ends up truly needing to use any form of pesticide on gardens or in your home, be sure to follow all safety instructions of application and disposal to not only protect ourselves and our families, but also as much nature as possible (EPA 2017).
Insects have the potential to be extremely invigorating. No matter the cost, in the end all insects benefit the world, but in the end they all have a purpose in some form or another. There are unlimited numbers of animal species such as various fish, multiple species of mammals, like Aye-Ayes, bats and anteaters, reptiles and amphibians that are known to consume these invertebrates. Insects are also known to eat other insects. Whether they help pollinate and feed well over thousands of animals or other insects for dietary needs or destroy agricultural products or the environment; insects will always remain a conflict of interest in the eyes of the human population. Managing and protecting them will also protect other forms of life.
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