National Geographic Society

Prompt action is needed at the federal level to limit the number of invasive pythons released into the wild, South Florida Water Management District (SFWMD) Deputy Executive Director George Horne said in written testimony to the U.S. Congress today.

The House of Representatives Subcommittee on Crime, Terrorism and Homeland Security is considering a Bill that would classify nonnative pythons, such as the Burmese python, as "injurious animals" and ban their importation into the United States.

Hypothetical diet necessary for a hatchling Burmese python to reach 13 feet in the Florida Everglades (approximately 5 to 7 years)

1 raccoon
1 oppossum
4 five-foot alligators
5 American coots
6 little blue herons
8 ibises
10 squirrels
15 rabbits
15 wrens
30 cotton rats
72 mice

This illustration, and the photos on this page were appended to the SFWMD written testimony handed to Congress today.

(Source: Skip Snow, Everglades National Park & Dr. Stephen Secor, University of Alabama)

"As a top predator and prolific breeder, these exotic snakes threaten state and federal efforts to restore America's Everglades, and they prey on the natural wildlife that call the Everglades home, including species already threatened or endangered," SFWMD's Horne said in its testimony to Congress today.

"We have a long history of successful invasive plant management and experience, but only recently have we had to commit more and more resources to the emerging populations of the Burmese python and other nonnative constrictors appearing across our landscape.

"If effective preventative programs were in place to limit introductions of nonnative constrictors, such as the legislation now under consideration, these much-needed taxpayerfunded resources could be redirected to other important resource management efforts.

"Today, however, the negative impacts from the unlimited importation of new pest animals require active responses on our part. Effective prevention of additional introductions of potentially invasive constrictor snakes, as proposed in this Bill, is the only path to prevent these costs from continually increasing."

While Florida, California and Hawaii are among the states most impacted by introduced invasive species, every state is affected, Horne added.

Photo of Burmese python killed in Florida courtesy of SFWMD

"Globally, exotic invasive species, including pest animals, weeds and pathogenic diseases, are a major cause of global biodiversity decline. In particular, nonnative animals compete for food and habitat, upset existing predator/prey relationships, degrade environmental quality, spread diseases and, in our case, may threaten the integrity of flood protection levees and canal banks, and electrical power delivery.

"Nationally, more than 50,000 species of introduced plants, animals and microbes cause more than $120 billion in damages and control costs each year. Already, 192 non-native animal species are established in Florida, calling for the development of methods to forecast and respond to the potential economic loss, environmental damage and social stress caused by both new non-native animal introductions and long-established invasive organisms."

The Bill before Congress makes an important contribution towards prevention by limiting the importation of two snake species (the Burmese and African python) with high invasion potentials in the U.S., Horne said.

"The amendment could also be expanded to include all giant constrictor species determined by the U.S. Geological Survey, or USGS, to have medium or high invasion risk potential. The recently published USGS risk assessment for giant constrictors ranked nine species as having either a medium or high overall risk potential for invasion in the United States.

"These species include the Beni Anaconda, boa constrictor, Burmese python, DeSchauensee's anaconda, green anaconda, northern African python, southern African python, reticulated python and yellow anaconda.

Photo of Burmese python killed in Florida courtesy of SFWMD

"We strongly support inclusion of these species in [the Bill] in order to immediately limit importation of species that our best science predicts will be invasive. Rather than wait for the next Burmese python to become established in the United States, a proactive approach such as the proposed legislation being discussed today is urgently needed to protect our environment, economy and quality of life--not just in Florida but throughout the nation."

The South Florida Water Management District is deeply committed to preserving and restoring South Florida's environmental health and, unfortunately, the Everglades ecosystem is now home to the invasive Burmese python, Horne said.

Photo of eggs in Burmese python killed in Florida courtesy of SFWMD

The snake is a top predator that is known to prey upon more than 20 native Florida species. Notable among these are the federally listed Key Largo wood rat, white-tailed deer, American alligator, bobcat and numerous wading birds common to the Everglades, including the wood stork.

"Attempts to manage Burmese pythons divert taxpayers' funds from these other urgent primary restoration and protection tasks. Yet, failure to do so will leave this aggressive animal as a serious impediment to our Everglades restoration progress," Horne said.

Small livestock likely prey

The Burmese python also threatens agricultural interests as small livestock are also likely prey, Horne added.

Since 2000, the South Florida Water Management District and Everglades National Park, have removed 1,248 Burmese pythons from the Everglades.

"Adverse experience already gained in Florida strongly indicates the need to regulate the importation and sale of this snake. Without stronger regulation and control resources, adverse impacts of Burmese pythons will continue to get worse, and the python's population will continue to expand north of the Everglades and likely into South
Florida's urban areas."

Photo of Burmese python nest eggs in Florida courtesy of SFWMD

Florida's other nonnative giant constrictors

Given South Florida's abrupt boundaries between dense human population centers and vast subtropical wilderness areas, it comes as no surprise that numerous giant constrictor species have been observed in Florida, Horne said.

"While most observed animals are presumed to be released pets, three additional constrictor species are now considered established or potentially established in Florida--the common boa, northern African python and yellow anaconda.

"All three species are identified in the USGS risk assessment as having a high overall risk of establishment in the
United States. The common boa has been repeatedly observed in South Florida, primarily on the Deering Estate in eastern Miami-Dade County, but also near Everglades National Park.

"Between 1989 and 2005, 96 common boas were captured in South Florida.

"Recent confirmed sightings of northern African pythons near the eastern boundary of the Everglades and yellow anacondas near Big Cypress National Preserve and Myakka State Park in southwest Florida are also cause for alarm."

"Recent confirmed sightings of northern African pythons near the eastern boundary of the Everglades and yellow anacondas near Big Cypress National Preserve and Myakka State Park in southwest Florida are also cause for alarm. All three of these species share traits with the Burmese python that are considered important factors for invasive potential, and like the Burmese python all three species will be very costly to control should they become widely established."

Burmese python photo courtesy of South Florida Water Management District

As the South Florida Water Management District and other agencies try to contain the documented damage and growing threat of the Burmese python and other invasive animals in Florida, the flow of potentially harmful exotic animals across U.S. borders continues, Horne said.

"To use just one example, roughly 144,000 boa constrictors were imported into the United States between
2000 and 2007.

Federal action is needed now to address the immediate threat posed by giant constrictors which have or are likely to establish in our nation's wilderness areas."

As we observe the 150th anniversary this month of the first publication of Charles Darwin's On the Origin of Species, a new book reviews evolution and ranks the top one hundred most influential species of all time.

Homo sapiens is not at the top of the list.

In fact, we humans, who like to imagine that we are the masters of the universe, don't even rank in the top five.

The most influential species (defined as the species that has most changed life on Earth) is ... the earthworm.

Photo courtesy USDA

"According to Charles Darwin, no living thing has had such a profound impact on history as has the earthworm," says Christopher Lloyd, a history scholar at Cambridge University, UK, and author of What on Earth Evolved?: 100 Species that Changed the World (Bloomsbury, November 2009, $45).

After considering the most important species that evolved before the ascent of human civilization, from the beginning of life on Earth until about 12,000 years ago, and then mulling all the species that have been successful since 12,000 years ago--that is the species that have flourished because of modern humans--Lloyd finds that he agrees with Charles Darwin: The earthworm is indeed the most influential species in the history of the planet.

Descendants of sea worms that existed five hundred million years ago, earthworms came ashore with the first invertebrate invasions of the land, making their living in damp soils broken up by bacteria, fungi and the roots of colonizing plants, Lloyd writes. "These earthworms have been ploughing up the earth, ventilating the soil and nourishing terrestrial ecosystems with their excrement ever since."

The survivors of five mass extinctions, earthworms have had profound impacts on human history, Lloyd says.

"Were it not for their continuous regeneration of soils around damp river valleys such as the Nile, Indus, and Euphrates, early agricultural societies in Egypt, India, and Mesopotamia could never have succeeded in building humanity's first large-scale urban communities." 

"Wherever eathworms plough, people thrive. When worms perish, societies collapse."

Throughout human history earthworms have unintentionally but undeniably triggered the rise of civilizations, Lloyd adds. "Wherever eathworms plough, people thrive. When worms perish, societies collapse."

The European earthworm (Lumbricus terrestris) is probably the most prolific and invasive species in the world, Lloyd says.

"Its success is largely thanks to the spread of Europeans, c. 1600 onwards.

"Immigrant farmers inadvertently brought these earthworms, sometimes called 'night crawlers,' in everything from the soil in their potted plants and their horses' hooves, to the treads of their boots and the wheels of their wagons.

"Today there is hardly a region of North America where Europe's earthworms have not made a home for themselves. There they continue to plough, ventilate and fertilize the soil to the general benefit of life in and on the Earth."

Before Man, After Man

What on Earth Evolved? is divided into two sections--Before Man and After Man. Starting with the early Earth, when loose strands of genetic code swarmed the planet, Lloyd explores the most significant lifeforms that evolved in the deep oceans and then wriggled ashore to become pioneers of life on land. In the second section, the author shows how co-evolution of humans and numerous other key species transformed Earth over the past 12,000 years.

A newspaper science and technology correspondent in a previous career, Lloyd has produced an accessible read, guiding the reader through capsule biographies of a hundred of the most influential species. They include slime, sea scorpions, dragonflies, potatoes, ants, tulips, sheep, dogs, cats, coca, opium, poppies, and grapes.

He ranks the species into a table of influence, revealing those that have most changed life on Earth. Academics will no doubt debate the selection and process, but Lloyd makes a compelling, albeit concise, case for each species. The full list of the hundred most influential species may be seen on the book's Web site, or in the book itself.

Covering all of life in one book would be impossible, of course, but Lloyd has taken an interesting approach to some of the most marvelous products of evolution, leading to renewed appreciation of how much life has succeeded through both competition and collaboration.

Here is Lloyd's top ten most influential species of all evolution:

Evolution's top ten species

1. Earthworm
Made it possible for humans to cultivate the planet, settle, and build civilizations.

2. Algae
Without the countless forms of microscopic algae, larger forms of sea life would never have been able to evolve. All land plants are descended from ancestral forms of algae.

3. Cyanobacteria
Plants, trees, and animals all owe their existence to the presence of oxygen in the atmosphere and oceans, supplies of which were originally established by cyanobacteria, a photosynthesizing bacterium that breaks down carbon dioxide and excretes oxygen.

4. Rhizobia
Organisms capable of "fixing" atmospheric nitrogen into soluble nitrates that fertilize the soil so that plants and trees can thrive.

5. Lactobacillus
Bacteria that live inside the human colon, providing beneficial services such as assistance with digestion of milk and protection against harmful bacteria and organisms such as viruses and fungi.

6. Homo sapiens
Humans did not crack the No. 1 position on Lloyd's list, but we merit five pages in his 416-page book and we are the only mammal in the top 10. We lose points chiefly as a result of our recent evolutionary emergence.

We may not rank as the most influential species in this analysis, but our impact pervades the past 12,000 years as we learned to farm animals and plants and harness mch of the resources of the planet.  In that time humans have had a profound impact on many other species, nurturing those useful to us and driving many that are of little value to us into isolation and even into extinction. Our impact on evolution is clearly in its early phases.

7. Stony corals
Coral reefs are powerful places for the natural conservation and co-operation of species, resulting in the construction of massive undewrwater mountains that house an extraordinary diversity of life.

8. Yeast
It is almost exclusively thanks to the action of this single-celled microscopic fungus that humanity has been able to enjoy everything from leavened bread to fine wine. Some of our best prospects for fuelling sustainable industrialization and transportation in the future are based on ethanol, a by-product of yeast.

9. Influenza
One of humanity's biggest ever killers and still the largest threat to populations on Earth.

10. Penicillium
A naturally occurring antibiotic that has transformed modern medicine and substantially increased human populations.

Bloomsbury Publishing provided a copy of What on Earth Evolved? for this entry.

The 2009 update of the IUCN Red List of Threatened Species shows that 17,291 species out of the 47,677 assessed species are threatened with extinction, the International Union for the Conservation of Nature said today.

Threatened with extinction are:

• 21 percent of all known mammals
• 30 percent of all known amphibians
• 12 percent of all known birds
• 28 percent of assessed reptiles
• 37 percent of assessed freshwater fishes
• 70 percent of assessed plants
• 35 percent of assessed invertebrates

"The scientific evidence of a serious extinction crisis is mounting," said Jane Smart, director of IUCN's Biodiversity Conservation Group, in a news statement accompanying the 2009 Red List.

This gorgeted puffleg (Eriocnemis isabellae) entered the IUCN Red List in 2009 as Critically Endangered. The species is known from southwest Colombia, where it occurs in a tiny area of the Serraníadel Pinche. The global population is not known but is presumably very small given that the area of suitable habitat available for this species is thought to be less than 2,500 acres, and it is suspected to be decreasing as elfin forest habitat is converted for agriculture and illegal coca plantations. The primary threat to this bird is the shifting of the agricultural border towards remaining primary forests, causing a loss of vegetation cover, contamination of watersheds and soil degradation. Illegal coca cultivation is a major threat due to the lack of governmental presence, with 8.3 percent of potentially suitable habitat reportedly damaged annually by coca cultivation.

Photo © Alex Cortes. Photo supplied by BirdLife International.

"It's time for governments to start getting serious about saving species and make sure it's high on their agendas for next year, as we're rapidly running out of time."

"January sees the launch of the International Year of Biodiversity," Jane Smart added in today's statement. "The latest analysis of the IUCN Red List shows the 2010 target to reduce biodiversity loss will not be met.

"It's time for governments to start getting serious about saving species and make sure it's high on their agendas for next year, as we're rapidly running out of time."

Tip of the iceberg

"This year's IUCN Red List makes for sobering reading," said Craig Hilton-Taylor, manager of the IUCN Red List Unit. "These results are just the tip of the iceberg. We have only managed to assess 47,663 species so far; there are many more millions out there which could be under serious threat. We do, however, know from experience that conservation action works so let's not wait until it's too late and start saving our species now."

Rabb's fringe-limbed treefrog (Ecnomiohyla rabborum) entered the IUCN Red List as Critically Endangered in 2009.

It is known only from central Panama, where it occurs in tropical forest canopy. In 2006, the chytrid fungus was reported in the area where this species is known to occur. Since then, only one individual has been heard calling. There is also some ongoing forest clearing within the species' range for the development of luxury holiday homes, although this potential threat has not yet reached critical levels. This treefrog is one of several species collected for captive breeding efforts, however so far attempts at captive breeding have not produced positive results.

Photo © Brad Wilson

Switzerland-based IUCN is a global environment organization that works on biodiversity, climate change, energy, human livelihoods and greening the world economy by supporting research, managing field projects, and bringing governments, NGOs, the United Nations and corporations together to develop policy, laws and best practice.

The IUCN Red List of Threatened Species is a comprehensive information source on the global conservation status of plant and animal species. It is based on an objective system for assessing the risk of extinction of a species should no conservation action be taken. Species are assigned to one of eight categories of threat based on whether they meet criteria linked to population trend, population size and structure and geographic range. Species listed as Critically Endangered, Endangered or Vulnerable are collectively described as "Threatened."

The Popondetta blue-eye (Pseudomugil connieae) occurs in three river systems within Papua New Guinea. Human population growth is the main threat to this fish, with increased urbanization and agriculture, which are potential sources of water pollution, resulting in reduced habitat quality within these river systems. This fish is also a much sought after species in the aquarium trade, which poses another potential threat to the population. The species entered the IUCN Red List as Vulnerable in 2009.

Photo © Gerald Allen

Highlights from today's IUCN statement:

Mammals

Of the world's 5,490 mammals, 79 are Extinct or Extinct in the Wild, with 188 Critically Endangered, 449 Endangered and 505 Vulnerable.

The eastern voalavo (Voalavo antsahabensis) appears on the IUCN Red List for the first time in the Endangered category. This rodent, endemic to Madagascar, is confined to montane tropical forest and is under threat from slash-and-burn farming.

Reptiles

There are now 1,677 reptiles on the IUCN Red List, with 293 added this year. In total, 469 are threatened with extinction and 22 are already Extinct or Extinct in the Wild.

The 165 endemic Philippine species new to the IUCN Red List include the Panay monitor lizard (Varanus mabitang), which is Endangered. This highly-specialized monitor lizard is threatened by habitat loss due to agriculture and logging and is hunted by humans for food.

The rare Panay monitor lizard occurs in large trees in primary lowland tropical moist forest. The species is a highly specialized frugivorous monitor lizard (it feeds on fruit). The loss and degradation of lowland forest habitat through conversion of land for agricultural use and logging operations is a threat to this lizard. The species is also hunted by humans for food and overhunting is a serious threat to the remaining population.

Photo © Tim Laman 

The sail-fin water lizard (Hydrosaurus pustulatus) enters in the Vulnerable category and is also threatened by habitat loss. Hatchlings are heavily collected both for the pet trade and for local consumption.

"The world's reptiles are undoubtedly suffering, but the picture may be much worse than it currently looks," says Simon Stuart, chair of IUCN's Species Survival Commission. "We need an assessment of all reptiles to understand the severity of the situation, but we don't have the U.S.$2-3 million to carry it out."

Amphibians

The IUCN Red List shows that 1,895 of the planet's 6,285 amphibians are in danger of extinction, making them the most threatened group of species known to date. Of these, 39 are already Extinct or Extinct in the Wild, 484 are Critically Endangered, 754 are Endangered and 657 are Vulnerable.

The Kihansi spray toad (Nectophrynoides asperginis) was formally declared Extinct in the Wild in the IUCN Red List in 2009. This amphibian was known only from the Kihansi Falls in Tanzania, where it was formerly abundant. However, after 2003 the population dramatically declined, and in January 2004 only three toads could be found, with just two males heard calling. There have been no records since then, despite surveys. The decline of this species was caused by the construction of a dam upstream of the falls in 2000 for the Lower Kihansi Hydropower Project. This removed 90 percent of the water flow, which hugely reduced the volume of spray and altered the vegetation. In 2003, the fungal disease chytridiomycosis was confirmed in dead Kihansi spray toads, and this disease was probably responsible for the final population crash.

Photo © Tim Herman

The fungus also affected the Rabb's fringe-limbed treefrog, which enters the Red List as Critically Endangered. (See photo and description higher on this page.)

Plants

Of the 12,151 plants on the IUCN Red List, 8,500 are threatened with extinction, with 114 already Extinct or Extinct in the Wild.

The Queen of the Andes (Puya raimondii) has been reassessed and remains in the Endangered category. Found in the Andes of Peru and Bolivia, it only produces seeds once in 80 years before dying. Climate change may already be impairing its ability to flower and cattle roam freely among many colonies, trampling or eating young plants. Other threats include young plants being eaten or trampled by livestock, fires, and removal of pith from trunks.

Photo © Antonio Lambe (Acción Ambiental)

 

Toussaintia patriciae is an Endangered shrub species native to Tanzania. It is known from less than 30 trees in the Udzwunga Mountains National Park and West Kilombero Nature Reserve, and occurs in very low numbers where found, though it is cryptic when not flowering and may be more common that is currently known. It is considered relatively secure at present, as the population is present in protected areas and occurs above the altitude to which firewood collectors are allowed to operate. However, this species could become more threatened very quickly if the impacts of human activities, especially wood collection, were to increase.

Photo © Quentin Luke

 

Invertebrates

There are now 7,615 invertebrates on the IUCN Red List this year, 2,639 of which are threatened with extinction. Scientists added 1,360 dragonflies and damselflies, bringing the total to 1,989, of which 261 are threatened.

The giant jewel (Chlorocypha centripunctata) is known from the Obudu Plateau, Nigeria and from Mount Kupe and the Bakossi Mountains Cameroon. The species occurs in and around rain forest streams above 700-meter altitude. Habitat loss through selective logging and forest destruction for agricultural expansion is the main threat to this species. The species entered the IUCN Red List as Vulnerable in 2009.

 

Photo © Kai Schütte

 

Molluscs

Scientists also added 94 molluscs, bringing the total number assessed to 2,306, of which 1,036 are threatened.

All seven freshwater snails from Lake Dianchi in Yunnan Province, China, are new to the IUCN Red List and all are threatened. These join 13 freshwater fishes from the same area, 12 of which are threatened. The main threats are pollution, introduced fish species and overharvesting.

Freshwater Fishes

There are now 3,120 freshwater fishes on the IUCN Red List, up 510 species from last year. Although there is still a long way to go before the status all the world's freshwater fishes is known, 1,147 of those assessed so far are threatened with extinction.

The giant pangasius (Pangasius sanitwongsei) is a Critically Endangered fish found in the Chao Phraya and Mekong river basins in Cambodia, China, Laos, Thailand and Vietnam. It inhabits the bottom and midwaters of large rivers surrounded by rain forest, and uses deep pools as refuges in the dry season. Overfishing for food, and to a lesser extent the aquarium trade, is the principle threat facing this species. Local fisherman have reported dramatic declines in sightings and catch, and a population decline of more than 99 percent over the past 30-45 years is inferred.

Photo © Chavalit Vidthayanon

The brown mudfish (Neochanna apoda), found only in New Zealand, has been moved from Near Threatened to Vulnerable as it has disappeared from many areas in its range. Approximately 85-90 percent of New Zealand's wetlands have been lost or degraded through drainage schemes, irrigation and land development.

The status of the Australian grayling (Prototroctes maraena), a freshwater fish, has improved as a result of conservation efforts. Now classed as Near Threatened as opposed to Vulnerable, the population has recovered thanks to fish ladders which have been constructed over dams to allow migration, enhanced riverside vegetation and the education of fishermen, who now face heavy penalties if found with this species

"Creatures living in freshwater have long been neglected."

"Creatures living in freshwater have long been neglected. This year we have again added a large number of them to the IUCN Red List and are confirming the high levels of threat to many freshwater animals and plants. This reflects the state of our precious water resources. There is now an urgency to pursue our effort but most importantly to start using this information to move towards a wise use of water resources," said Jean-Christophe Vié, deputy head of the IUCN Species Programme.

Downlisted bird species

The Mauritius fody (Foudia rubra) was downlisted from Critically Endangered to Endangered because its extremely small population has been stable since the early 1990s and is now increasing following an island translocation. The species is restricted to southwest Mauritius, and suffered rapid population declines between 1975 and 1993. However, since 1993 the population has been stable, and there is evidence that dispersing juveniles are now setting up new breeding territories, expanding the range of the species. Historically, clearance of upland forest, particularly for plantations in the 1970s, catastrophically affected this species. Introduced predators (e.g. black rat (Rattus rattus) and crab-eating macaque (Macaca fascicularis)) caused almost total breeding failure in most areas, and nest predation is still the major threat to the species.

Photo © Lucy Garrett (Rare Birds Yearbook). Photo supplied by BirdLife International.

Global figures for 2009 IUCN Red List of Threatened Species:
Total species assessed = 47,677
Total Extinct or Extinct in the Wild = 875 (2%) [Extinct = 809; Extinct in the Wild = 66].
Total threatened = 17,291 (36%) [Critically Endangered = 3,325; Endangered = 4,891; Vulnerable = 9,075].
Total Near Threatened = 3,650 (8%).
Total Lower Risk/conservation dependent = 281 (<1%) [this is an old category that is gradually being phased out of the Red List]
Total Data Deficient = 6,557 (14%)
Total Least Concern = 19,023 (40%)

Global figures for 2008 IUCN Red List of Threatened Species:
Total assessed = 44,838
Total Extinct or Extinct in the Wild = 869 (2%) [Extinct = 804 ; Extinct in the Wild = 65]
Total threatened = 16,928 (38%) [Critically Endangered = 3,246; Endangered = 4,770; Vulnerable = 8,912]
Total Near Threatened = 3,513 (8%)
Total Lower Risk/conservation dependent = 283 (<1%) [this is an old category that is gradually being phased out of the Red List]
Total Data Deficient = 5,570 (12%)
Total Least Concern = 17,675 (39%)

Not all species on the IUCN Red List are threatened. There are now more species on the IUCN Red List. This means that the overall percentage of threatened species has gone down by two percent. This is not because the status of the world's biodiversity is improving, IUCN noted, but because we have assessed more species.

"In the past, Red List assessments often focused on species that were already thought to be threatened, but as the Red List grows to include more complete assessments across entire groups, we are beginning to have a better idea of the relative proportion of species which are threatened against those which are not threatened."