STOP! YOU’RE SURROUNDED!

A treasure trove of biological diversity

Before you read any further, stand up. Take this magazine with you and go outside. Have a look and a listen. Odds are wherever you are in Maryland you are surrounded by hundreds of different kinds of animals.

Some are obvious and out in the sunlight; they sing, dance and display. Butterflies flit amongst the flowers; birds and cicadas sing in the trees. Some creatures are hidden, masters of camouflage, lurking in the shadows or emerging only at night.

Even now, the wheelbugs are watching you, as are vertebrates and invertebrates, mammals, birds, reptiles, amphibians, insects, mollusks, fish, butterflies, houseflies, dragonflies, bee flies, leafhoppers, slugs, ticks, turtles, shrews, isopods, mice, foxes, snakes… The list seems endless!

Maryland is a treasure trove of native plant and animal diversity. Its geography, bounded by mountains, rivers and sea, includes natural communities to suit any habitat need. Its place at the mid-Atlantic latitudes puts Maryland at the intersection of northern and southern species ranges.

Simply put, wildlife diversity is the many forms that animal life takes. When that diversity includes plants, fungus or other non-animal life forms, we call it biological diversity or biodiversity. Relationships between these animals and plants form a “web of life” that functions like a complex and fluid dance.

By the numbers

Maryland is home to 97 kinds of mammals, 410 species of birds (including breeding and non-breeding), 52 kinds of reptiles (snakes, turtles, lizards), 41 kinds of amphibians (frogs, toads, salamanders) and 635 species of fish (freshwater and saltwater).

The number of invertebrate species, those without a backbone, is estimated at over 20,000. Surveys have been conducted on the “prettier” species, like butterflies (148 species) and dragonflies and damselflies (185 species).

Current estimates of native bees place the number of species in Maryland between 350 and 400. Work continues on the more obscure groups.

Historical losses

With this embarrassment of riches in wildlife diversity, we take for granted that it was ever thus and ever shall be. Any Maryland third grader can tell you that John Smith and his crew were impressed by the creatures they saw on their voyages up the Chesapeake. However, there are at least 135 fewer native plants and animals than there were at the time of Smith’s expedition. Since European settlement and written records began, Maryland’s landscape has lost most of its large mammals, like the woodland bison, elk, gray wolf and cougar. You may know about the now-extinct passenger pigeon and its fabled flocks so huge they darkened the sky for hours.

But did you know Maryland used to have colorful green, gold and coral parakeets? The Carolina parakeet was a native bird that left Maryland skies in 1865 and became extinct globally in the 1920s.

These are examples of species we know are gone. We have fewer records on less showy species, secretive creatures and plants. Research has leaned heavily on animals with backbones. Certainly, scientists are guilty of what Harvard researcher and early champion of biological diversity E. O. Wilson called “vertebrate chauvinism” when it comes to studying nature.

Nature as a provider

This great variety of wildlife is what makes it possible for humans to live here. Game birds and mammals along with an abundance of fishes have provided food, clothing and tools to human inhabitants for thousands of years.

Shellfish from the Chesapeake Bay gave sustenance and materials for trading up and down the East Coast. The first cash crop sent back to England by the early settlers was not tobacco but sturgeon. Atlantic and shortnose sturgeons were a source of meat. The skin could be tanned like leather, and the roe, or eggs, was a luxury for high society.

Even now, animal species alone are responsible for billions of dollars flowing into our economy… hunting and trapping supplies and clothing, outfitters and guides, binoculars for watching birds or butterflies, field guides, insect nets and cages, boats and fishing gear, the list goes on. Approximately 15 percent of all animals are considered game species; the rest are non-game.

Even people who want nothing to do with wildlife have had their lives touched by it. Blood from horseshoe crabs is used in medical research to identify harmful bacteria and to aid in treatments for metabolic disorders. There is more and more evidence supporting the benefits of wildlife and land conservation on the psychological and physical health of human societies.

Balancing act

Of course, it’s not always all about us. Aside from wildlife’s inherent value, it also serves an ecological purpose. Natural systems function in a delicate balance. If one part of the system is disturbed, the balance is thrown off. Natural processes may falter, becoming less efficient, leading to a cascade of problems.

For instance, many animal species eat insects. Bats, dragonflies, frogs and toads all prey on insects. Imagine how many mosquitoes there would be if the natural predators did not fill that role.

Pollination is a crucial ecosystem function performed by wildlife. Many of our native plants have co-evolved with our native pollinators. The tube-shaped flower of the trumpet-creeper accommodates the long beak and brushy-tipped tongue of the ruby-throated hummingbird or the hollow “drinking straw” tongue of the large orange sulphur butterfly. The animal gets a meal and the plant gets pollination, and sometimes seeds are transported. One depends on the other for survival. Some of our agricultural crops also depend upon these pollinators.

Non-native animals simply cannot fill this role as effectively as natives and may instead, do damage to the ecosystem. Look to the nutria or the gypsy moth as examples of failed experiments with introduction.

Diversity challenges

Threats to Maryland’s wildlife diversity exist. The State Rare, Threatened and Endangered species list includes more than 600 species.

Most State-endangered species are plants (265); 79 are animals. Additionally, 79 plants and 20 animals are considered threatened. A fraction of these 600 species are also on the federal endangered species list. These include the Delmarva fox squirrel, bog turtle, dwarf wedge mussel and shortnose sturgeon – which never recovered from over-fishing in the early colonial period.

If we include other vulnerable species not granted legal protection status, the State list expands to more than 1,000 species of plants and animals.

Cause and effect

Each rare species may have different reasons for its vulnerability. Of human-related causes, there are four major categories. The most significant is habitat loss and fragmentation, which can be caused by several factors. Poorly planned development is one.

Inadequate forestry practices, which don’t recognize the need for functioning habitat, and improper agricultural practices, like over-grazing or inadequate forested boundaries along streams, also can contribute to habitat loss.

A second human-related cause is invasion by non-native plant and animal species. Whether introduced accidentally or intentionally, these invaders are the fastest growing reason for habitat degradation. Often there is no natural control of these exotic species and they can overwhelm the landscape.

Air and water pollution may come from several sources. Some sources can be tracked to the offender. The classic scenario is the “giant pipe from a factory spilling into a stream,” called point source pollution.

Some are harder to pinpoint. These are called non-point source. Fertilizer run-off from lawns or car fluids washed from roads is non-point source pollution.

Finally, collection, once the greatest direct threat to many showier species, is now fourth on the list, thanks to greater enforcement.

Two overarching themes must be highlighted on this list: human population growth and all that entails (housing, food, clothing, space for an ever growing humanity), and climate change with sea level rise.

Working alongside nature

Certainly, the outlook is dark for the future of our wild populations. Doom and gloom may be the watchwords of the day. But, as these ills are man made, so too are their cures… such as changing development patterns so buildings share facilities like sewage treatment, planned greenspace and reducing overall sprawl.

Recognizing that smaller houses or cluster housing are easier to maintain and cheaper to heat and cool will decrease impact on the landscape while helping to increase bank accounts.

Changing our housing landscapes from large lawns which require fertilizers or pesticides and watering and maintenance will not only free up personal time but also send fewer chemicals into our waterways.

Better yet, convert part of the lawn to perennial beds of native plants. You will shrink your mowing time while creating habitat for our native birds, butterflies and bees. A classic “win-win” solution for all!

Funding hope

At the federal and state level, work is being done to learn more about wildlife diversity. Federal funding from the State Wildlife Grants program is used to study the lesser known species and their habitats in Maryland. These funds are helping to conserve wildlife diversity comprehensively for the first time in the almost 100 year history of the Department of Natural Resources (DNR).

As part of this endeavor, DNR’s Wildlife and Heritage Service has produced the Maryland Wildlife Diversity Conservation Plan. Written in 2005, this plan is designed to provide a framework and direction for wildlife conservation efforts for the next decade and beyond. The plan is available in full on the DNR website.

Time for a change

It has taken a few hundred years to get to this point for our diverse wildlife populations. Problems won’t be solved overnight. We will have to learn new ways to live and think while making a smaller impact on the land.

It will take a concerted effort by all, recognizing that our own survival is inextricably linked to the strength and health of our natural diversity.

But changing our behavior will be less painful knowing that we are improving our own lives along with the biological diversity of Maryland’s bountiful natural world.

Paula G. Becker is Outreach Ecologist/Volunteer Coordinator with DNR’s Wildlife & Heritage Service Natural Heritage Program.

• Check Out Habichat Wildlife and Heritage Services Quarterly Newsletter
• Endangered Species - Plants & Animals
• Maryland's Natural Heritage Program
• Invasive and Exotic Species

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