Sunday, February 8, 2015

Maintaining and Protecting Pine Rocklands and Biodiversity

Miami Pine Rocklands Preservation Coalition Rally for the Rocklands
January 17, 2015_Copyright Sandy Koi

  The Importance of Maintaining and Protecting Natural Ecosystems, Especially the Pine Rocklands, an Environmentally Endangered Land

Biodiversity loss is occurring at an unprecedented rate, newly and aptly named the “defaunation” of our ecosystems. Urban interface areas, where the concrete meets the wild, are classic fields of controversy when conflicts between human wishes and endangered species are involved, and are occurring more and more frequently worldwide. This is especially troubling when the ecosystems supporting endangered, threatened, vulnerable and imperiled life forms are themselves under threat. When these geographical areas are also recognized as biodiversity hotspots globally, this devastation is a conservation concern of even greater import.

The foundations of life on this planet are literally upheld by the vast abundance and diversity of invertebrates, but are largely ignored for the services they perform. Insects and other invertebrate life forms occupy every trophic level, niche and habitat in existence; they perform requisite ecosystem services, including pollination, the cycling of organic material in both soil and water, atmospheric nutrient exchange, provide food resources for many other vertebrate and invertebrate life forms, control over-population levels of other vertebrate and invertebrate life forms, and provide innumerable other services that allow life to exist on the planet we inhabit.

So when people ask, “Why should we care? What good are they?!” We should respond as E.O. Wilson did when someone asked him why we should care about ants: “What good are YOU!?”

If you are not being a responsible consumer, recycling, eating local produce, supporting the environmental programs at your children’s schools, and all of those other humane, conscientious choices in everyday life, you are taking and putting nothing back into the ecosystems that support us. We live in a terrarium. As one person’s sign stated at the Rally, “There is no planet B.” to which to escape.


Scientists demonstrate that more than half of monitored invertebrate populations of insects show a nearly fifty percent decline in abundance. Seventy-five percent of global food crops are pollinated by insects and terrestrial defaunation is cited as a major driver in ecological changes, playing a major part in the Earth’s sixth mass extinction event. Shortly after the term "defaunation" was coined late last year, marine biologists noted the same frightening loss of biodiversity and abundance of marine life in our oceans. In other words, we are losing species at an unprecedented rate.We do not seem to understand that we depend on the biodiversity in the natural environment to maintain a healthy planet.

The numbers and types of butterflies and moths is almost 8 times higher in undisturbed habitat than in disturbed sites, such as housing developments, roadways and shopping plazas. Climate change has also expanded or reduced potential range of many insects, but human-altered landscapes very often impact an animals’ ability to move across inhospitable habitat preventing them from reaching new establishment sites, even if they exist.

These non-native patches further inhibit some of these insects’ ability to disperse or to self-establish new colonies without assisted relocation. In addition, it is becoming increasing difficult to find suitable locations for re-location or assisted translocation because of increased habitat degradation. It has been stated that we may be reaching a point where restoration of species is no longer a viable alternative because of the anthropomorphic alteration of the remaining landscapes.

South Florida’s natural areas are rapidly diminishing, but as part of the Caribbean archipelago it is considered a hotspot for biodiversity and rates high for conservation priorities. Endemic plants, insects and animals are under the constant barrage of invasive non-native species, urban pollution, and the unnatural fertilizers, pesticides and herbicides required to maintain the heavily manicured non-native landscapes of many developments. Mosquito control spraying in occupied areas is necessary to protect humans from devastating diseases such as West Nile Virus; however, its impact on non-target insects has been shown to be detrimental to the insects that act as vital crop pollinators, the insects that are break down organic matter to form soil, and the insects that provide food resources for other wildlife, such as migrating birds.

Developers often choose to landscape with non-native, and sometimes invasive, ornamental plants, most of which do not contain nectar for insect pollinators, such as beetles, butterflies and moths, as well as birds. There are many other factors that affect butterfly survival as well, including food plants, weather and disease. But the destruction of the natural environment is one of the most ecologically expensive factors; when habitats are devastated, not only are larval host plants and native nectar sources destroyed, we also lose the biodiversity found in a coherent environment and these disrupted environments often create havens for non-native invasive plant and animal species, thus doing further damage.

Pine rocklands are distinctive to South Florida, Cuba and the Bahamas and contain unique plants and animals that are highly adapted to a rather harsh environment with a limestone substrate that is subjected to stochastic weather events, including hurricanes, floods and droughts. They are categorized as globally endangered by the Florida Natural Areas inventory and are considered “Environmentally Endangered Lands” (EELs) by Miami-Dade County. Has the county forgotten this somehow?!

Pine rocklands contain a rich biodiversity in flora and fauna. Hundreds of rare plants are endemic to this ecosystem. The Richmond tract, for example, contains over 280 taxa of native plants, including two federally endangered plants, including Small’s polygala and Deltoid Spurge. Thirty-three plants on this property are considered threatened or endangered by the State of Florida.

Eighteen species of butterflies are listed as imperiled, meaning that they are in need of urgent conservation action. Butterflies are highly regarded as model organisms for research in ecology and evolutionary and act as a surrogate for monitoring biological diversity and health in an ecosystem. (In other words, they are “the canary in the coal mine.”)

Florida Purplewing butterflies are now found in very isolated and small populations, one of which is the Coastguard pinelands next door to this property. Protecting the surrounding areas is vital for its continued survival. The Atala butterfly was called “the most conspicuous insect in semi-tropical Florida” in 1888, but by the early 1950’s the Atala was not only rare, it was feared to be extinct because of the destruction of its host plant and pine rockland ecosystem. It now thrives in the remaining pine rocklands, including this site and has adapted well to domestic gardens that provide the needed host plants for the butterfly and its offspring.

Home gardens located near these remnant preserves provide vital pathways that extend essential natural corridors IF the butterflies can get them. Although the host plant, coontie, is often used as an ornamental in landscaping commercial properties, if the butterfly finds the plants, the caterpillars will defoliate it, and the property managers usually resort to a pesticide for control. So even if the butterfly finds a new site, it is still potentially in peril.

Bartram’s Scrub Hairstreak and the Florida Leafwing were recently listed as Endangered by the federal government, and they live here and in the remaining pine rocklands. Bartram’s, the Florida Leafwing and the Atala butterflies all use specific host plants. The host for Bartram’s and the Leafwing is pineland croton, which is seldom found outside the remaining vestiges of pine rocklands in southeast Florida. It is not a plant likely to be found in any urban garden except for the most attentive of native plant enthusiasts. Even so, the proximity of those gardens to pine rockland fragments would practically be a pre-requisite for hosting a Bartram’s Scrub Hairstreak or a Florida Leafwing in a backyard garden.

Pine rocklands are increasingly under threat by developers and county commissioners who seem to wish to pave over what remains of this rare and unique ecosystem. Less than 2% of the original pine rocklands remain outside of Everglades National Park, The largest tract outside of Long Pine Key is Navy Wells, but the Richmond tract is the second largest, containing 21% of the remaining pine rocklands!

Another rare insect is the Miami Tiger Beetle, first described in 1934, but not seen again for over 70 years. It was rediscovered here in 2007 and there are many, many other plants and animals we could talk about!
Protecting this disappearing habitat and maintaining its ecological coherence to support the species living in it is of vital importance and the only ethical choice. Aldo Leopold wrote: “A thing is right when it tends to preserve the integrity, stability and beauty of the biotic community. It is wrong when it tends otherwise.”

(References for these statements & data available on request!)

Happy Tu B'Shevat, called the "Birthday of the Trees", to all.


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