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Endangered Species Dr. Sukanya Datta An endangered species is a population of organisms, at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or by predation. Extinction is the situation when there are no longer any living individuals of a species left. Once a species is extinct there is no way we can bring it back. The moment of extinction is generally considered to be the death of the last individual of that species (although the capacity to breed and recover population numbers may have been lost before this point). A species may become functionally extinct when only a handful of individuals survive, which are unable to reproduce due to poor health, old age, sparse distribution over a large range, a lack of individuals of both sexes, or other reasons. Extinctions are an integral part of the natural scheme of things. There have been five periods of mass extinction’s on Earth. These took place 440million, 370million, 250million, 210million and 65million years ago respectively. These were natural processes unique for each species Just as each species is unique, so is each extinction... the causes for each are varied—some subtle and complex, others obvious and simple. Dinosaurs, for example, are extinct animals. But their extinction came about by the process of evolution whereby less successful species are replaced by more successful ones. The extinctions taking place today do not always fall into the same category. Destructive human activities have led to the current rate of species extinction, which is at least 100–1,000 times higher than the expected natural rate. One in four of the world’s mammals are now threatened with extinction in the near future. So are one in eight birds, one in five sharks, one in four coniferous trees, and one in three amphibians. According to NatureServe’s global conservation status, approximately thirteen percent of vertebrates (excluding marine fish), seventeen percent of vascular plants, and six to eighteen percent of fungi are considered imperilled. Species, and the ecosystems they are part of, provide essential goods and services that make human life possible and contribute enormously to our health and well-being. Biodiversity gives us breathable air, clean water, food, fibres, building materials, medicines, energy, fertile soils, balanced/regulated climate, transport, allows us to pursue recreational activities and may have spiritual significance. Biodiversity is affected by human activity. The consequences of rapid and tremendous industrialization has manifest as pollution. A polluted environment (or even a changed environment) threatens the survival of any species that cannot adapt to it. Already many species have vanished forever. Many others are poised on the brink of extinction. This is because any species that is unable to survive or reproduce in its environment, and unable to move to a new environment where it can do so, becomes extinct. Extinction of a species may come suddenly when an otherwise healthy species is wiped out completely, as when toxic pollution renders its entire habitat unliveable; or it may occur gradually over years, such as when a species gradually loses out in competition for food to better adapted competitors; or even if it is hunted to levels when none is left to carry on the name of the species. Before the extinction of a species; there is a time when the population drops below a certain number. This number is the absolute minimum needed for maintaining a viable population. Steps need to be taken for conservation much before this number is reached. To be able to do that one needs to know the status of the population. IUCN Red List of Threatened Species™ The conservation status of a species is an indicator of the likelihood of that endangered species will go extinct. The IUCN Red List of Threatened Species™ is widely recognized as the most comprehensive, objective global approach for evaluating the conservation status of plant and animal species. The IUCN Red List of Threatened Species was created to assess and monitor species at a global level and to highlight their risk of extinction, therefore promoting their conservation. IUCN Red List has been adopted by the Parties to the Convention on Biological Diversity to monitor the worlds’ progress in reducing biodiversity loss by 2010 and beyond. The IUCN Red List is updated at least once each year and a new version number is allocated to each update. The March 2010 update is version 2010.1. Many factors are taken into account when assessing the conservation status of a species. It does not solely depend on the surviving numbers but also on the overall increase or decrease in the population over time, breeding success rates, known threats, and so on. The IUCN Red List of Threatened Species does not use “endangered species” as a general term. When this term appears in the IUCN Red List, it actually means a specific category of imperilment. Conservation Status Categories Extinct: Dodo. Passenger Pigeon. The idiom: As Dead as a Dodo is evocative of a species lost forever. Extinct in the wild: Captive individuals survive, but there is no free-living, natural population and these species are maintained only in zoos or other artificial environments. Some of these species are functionally extinct, as they are no longer part of their natural habitat and it is unlikely the species will ever be restored to the wild. Example: Guam Rail. Critically endangered: This is the highest risk category assigned by the IUCN Red List for wild species. These species face an extremely high risk of extinction in the immediate future. Example: Mountain Gorilla. Endangered: These face a very high risk of extinction in the near future. IUCN has calculated the percentage of endangered species as 40 percent of all organisms based on the sample of species that have been evaluated through 2006. Example: Dhole. Vulnerable: These face a high risk of extinction in the medium-term. Example: Komodo dragon. Conservation dependent: These species are the focus of a specific conservation programme, which if stopped, would result in the species becoming vulnerable, endangered or critically endangered within a period of 5 years. Example: Spotted Hyena. Near threatened: These may be considered threatened in the near future. Example: White Rhinoceros. The reason for rating this species as Near Threatened and not Least Concern is due to the continued poaching threat and high illegal demand for horn. Least concern: There is no immediate threat to the survival of the species. Example: Striped dolphin. Currently, 1,556 known species in the world have been identified as endangered, or near extinction. These are under protection by government law. This does not take into consideration the number of species ALSO threatened with endangerment but which are not included under the protection of such laws as the Endangered Species Act. IUCN does not consider a species extinct until extensive, targeted surveys have been conducted, species which are possibly extinct are still listed as 'Critically Endangered.' A new ideal category for 'Possibly Extinct' has been suggested by BirdLife International to categorize these taxa. The problem is that the extinction of one species' wild population can have effects on other species, causing further extinctions. These are also called “chains of extinction.” Keystone Species Keystone is an architectural term for the wedge-shaped piece at the summit of an arch, and which holds the other pieces in place. A keystone species is a species that exerts an impact on its community that is both strong and disproportionate to its abundance. This definition distinguishes keystone species from dominant species. The term was first used in Robert T. Paine in 1969. There are two hallmarks of keystone species. First, their presence is crucial in maintaining the organization and diversity of their ecological communities. Secondly, that these species are exceptional, relative to the rest of the community, in their importance. Starfish Pisaster ochraceus, feeds preferentially on mussels. By doing so, the sea star keeps a check on the populations of mussels and allows less competitive species to persist, thus enhancing local species diversity. The loss or decline of keystone species may have far-reaching consequences for the structure and functioning of the ecosystems in which they live. Even a small impact on keystone species could cause major disruption for the whole ecosystem. “Chains of extinction” are especially common with extinction of keystone species. Flagship Species These are iconic animals that provide a focus for raising awareness and stimulating action and funding for broader conservation efforts. Flagship species act as symbols for the threats to the broader ecosystem in which they occur, and can thus provide a catalyst for wideranging conservation activities. The Tiger is a flagship species; as are Clownfish, Koala, Panda and the Polar bear. The Polar bear is considered a charismatic icon for climate change. Pau Brasil (Caesalpinia echinata) is the national tree of Brazil, and gave the country its name. This Endangered species acts as a Flagship species for the threatened Atlantic Coastal Forest - a global biodiversity hotspot. Footprint-impacted species These are species whose populations are primarily threatened because of unsustainable hunting, logging or fishing. Hundreds of millions of plants and animals are harvested from the wild each year, from thousands of species. The Gulf of California porpoise ‘Vaquita’ or Phocoena sinus -- the world’s smallest and most endangered small marine mammal with just about 150 individuals alive, is a footprint impacted animal that is killed by fishing nets deployed to catch other species Foundation species is a dominant primary producer in an ecosystem both in terms of abundance and influence. Examples are corals in coral reefs. Indicator species is any biological species that defines a trait or characteristic of the environment. For example having only Tubifex worms is an indication that the water is severely polluted. Dominant species is the species that provides much of the biomass or number of individuals in an area. Keystone as well as Indicator species: Sea otters are a keystone species as well as an indicator species. When sea otters were almost exterminated by the fur trade their prey; sea urchins, proliferated and destroyed the kelp (algae) forests. When an indicator species population is doing well, that is a sign that the ecosystem is healthy. Southern sea otters began dying in 1995 from a disease that was associated with the prey they eat. Scientists realized that if sea otters have fatal disease associated with their diet, and humans eat many of the same items, we need to watch for similar health problems in people. Species forming a key element of the food chain and species which help the stability or regeneration of habitats are also categories of species that scientists study. This is because strategically focusing efforts on these species will also help conserve the many other species which share their habitats and/or are vulnerable to the same threats. So how do scientists decide how to choose a Priority Species? Priority species are especially important: (i) to the ecosystem... • Species forming a key element of the food chain • Species which help the stability or regeneration of habitats (ii) to human beings • Species important for the health and livelihoods of local communities • Species exploited commercially • Species that are important cultural icons. Reasons behind why species are endangered In order to conserve the biodiversity of the planet, one must take into consideration the reasons why so many species are becoming endangered. • Habitat loss is the most widespread cause of species endangerment. When an animal’s ecosystem is not maintained, they lose their homes. Then, they are forced to adapt to new surroundings or to perish. A leopard venturing into urban habitats where it is brutally clubbed to death is a victim of habitat loss. A bird that loses its chicks when a tree is chopped down is also a victim. • Pollution is another factor that causes many species to become endangered. When waters are polluted, many fish species disappear. • Over-exploitation, disease and climate change have led to the endangerment of several species; including microbial life. Humans have an impact on the species and their environment. As human use of resources, energy, and space intensified over the past few centuries, the diversity of life has been substantially diminished. • Humans also set standards for which species they think should be saved and which species they find unimportant or undesirable. • Being listed as an endangered sometimes makes a species more desirable for collectors and poachers. This effect is potentially reducible, such as in China where commercially farmed turtles may be reducing some of the pressure. However, even under such a scenario, the ‘farmers’ feel that an animal caught from the wild is genetically superior and so keep removing individuals from the wild. • Another problem with the listing species is its effect of inciting the use of the “shoot, shovel, and shut-up” method of clearing endangered species from an area of land. Some landowners perceive a diminution in value for their land after finding an endangered animal on it. Some opt to silently kill and bury the animals thus removing the problem from their land, but at the same time further reducing the population of an endangered species. How to Help Endangered Species? Helping preserve endangered species is the goal of conservationists who also want to create and expand ways to preserve endangered species and maintain biodiversity. Scientific research is one of the most fundamental actions in species conservation; for conservation measures to be most effective, the causes of decline and the ability of a species to recover must be fully understood. Once this has been established, recommendations can be put forward and the appropriate conservation measures implemented. The first step is to generate information, where sufficient data is lacking. For example, to understand the causes of population declines and extinction a study was conducted on the butterfly population in Finland. Butterflies are of particular interest to ecologists as they are very sensitive to environmental change, and are good indicators of wider changes. The study analysed the ranges of 48 butterfly species in Finland during two time periods: 1992-1996 and 2000-2004. It also investigated the relationship between the size of the range shift and various species traits such as body size, breeding habitat and the level of endangerment of the species. This study examined how species richness of butterflies with differing population trends is affected by land cover and climate. It was found that the butterflies’ distribution has declined by over fifty per cent, and they have a severely restricted habitat. Butterflies such as Grizzled Skipper were affected by habitat loss due to extensive draining of the bogs where they live. These observations suggest that climatic warming during the last ten years in Finland has had a strong influence on butterfly ranges. According to the results, the non-endangered butterflies had expanded their ranges more than the endangered species. This suggests that the threatened butterflies are less able to adapt to climate change, which is a concern for maintaining biodiversity. Furthermore, grasslands and bogs are declining habitats in Finland. The results suggested that habitat availability has the greatest effect on the trends of declining butterfly species. When we know the causes of endangerment, we can successfully create solutions for the management of biodiversity. Ecosystem Conservation Usually specific conservation efforts are paid to single species---the species that is showing a decline in population. Another approach is known as ecosystem conservation, where less focus is placed on preserving an individual species and more emphasis is given on preserving the proper functioning of the ecosystem as a whole. For example, the Northwest Hawaiian Islands Marine National Monument, is the largest marine protected area in the world; essential to the preservation of underwater communities and over-fished regions. Only researchers working in the area are permitted to fish, no corals may be removed, and satellite imaging monitors and places restrictions on vessels passing through these waters. The monument is home to an estimated seven thousand species, most of which cannot be found anywhere else in the world. This environmental monument demonstrates the fact that it is possible to create a safe environment for endangered species, as well as maintaining some of the world’s largest ecosystems. Proactive steps Since the threats affecting many of the species listed on the IUCN Red List are caused by humans, changing our behaviour can remove or lessen these threats and help species to recover. Conservation calls for cooperation among a wide range of sectors, including conservation scientists, governments, and local authorities and residents. Even individuals can help preserve species. Small steps, taken by many people, can make a huge difference. • Creating more awareness on environmental ethics can help encourage species preservation. Courses in ethics for students, and training programmes for ecologists and biodiversity managers could create environmental awareness and prevent violations of ethics in research and management. • Biological corridors, biosphere reserves, ecosystem management, and eco-regional planning are ways to integrate biodiversity conservation and socioeconomic development. • Captive breeding is the process of breeding rare or endangered species in human controlled environments with restricted settings, such as wildlife preserves, zoos and other conservation facilities. Captive breeding is meant to save species from going extinct. It is supposed to stabilize the population of the species so it is no longer at risk for disappearing. Captive breeding techniques are usually difficult to implement for highly mobile species like some migratory birds (e.g. cranes) and fishes (e.g. Hilsa). Additionally, if the captive breeding population is too small, inbreeding may occur due to a reduced gene pool. • Legal private farming. This has led to rise in the populations of both the southern black rhinoceros and the southern white rhinoceros. There are increasingly strong economic incentives attached to looking after rhinos rather than simply poaching. Scenario in India South Asia is one of the most biologically diverse regions of the world. The Eastern Himalaya, (zone extending from eastern Nepal through Bhutan, north-east India, south western China and western Myanmar) and the Western Ghats, in southwestern India are two of the world’s top 12 global hotspots of biodiversity. In the last half century, India's once rich biodiversity has become considerably depleted. Rapid population increase has led to exploitation of the country's bountiful wilderness areas. Species richness and the range of habitat types are highly eroded and fragmented. Institutions/Organisations Wildlife Institute of India The Wildlife Institute of India (WII) was set up at Dehradun in 1982 with a mandate to train government and non-government personnel, to carry out research, and advise on matters of conservation and management of wildlife resources. This was a time when wildlife science had not yet been established as a subject of any significance in the university education curriculum. WII's programmes are field based and seek an integration of biological, socioeconomic and human aspects of large regional landscapes. WII builds up scientific knowledge on wildlife resources; trains personnel for conservation and management of wildlife; carries out research relevant to management including the development of techniques appropriate to Indian conditions; provides information and advice on specific wildlife management problems; collaborate with international organizations on wildlife research, management and training. Conservation projects at WII include research on Olive Ridley turtles; monitoring endangered carnivores, mountain ungulates and pheasants in the Himalayas; assessment of the impacts of the tsunami on the Nicobar megapode; development of a conservation action plan for the hangul or Kashmir stag; carrying out status surveys of the Indian peafowl, Himalayan brown bear and Asiatic black bear; and listing of species in the IUCN red lists and reviewing the listing in the schedules of the Indian Wildlife (Protection) Act. Etc. WII is involved in many research projects dealing with the ecology and monitoring of endangered species in a wide range of study areas from the high Himalayas to the coasts and islands and the southern Indian Ocean and Antarctica. WWF-India WWF-India is one of the largest conservation organisations engaged in wildlife and nature conservation in the country. WWF-India is part of the WWF International family. WWF has a global presence in over 90 countries worldwide, with the coordinating body, WWF International, located in Switzerland. Historically, WWF-India started as a wildlife conservation organisation with a focus on protecting a particular species of wild flora and fauna. Over the years, the perspective broadened to reflect a more holistic understanding of conservation issues facing the country. To suit India's specific ecological and socio-cultural situation, WWF-India spelt out its mission in 1987. “The promotion of nature conservation and environmental protection as the foundation for sustainable and equitable development.” WWF India has made its presence felt through a sustained effort towards nature and wildlife conservation It has also created awareness through capacity building and enviro-legal activism. WWF-India addresses issues like the survival of species and habitats, climate change and environmental education. The Wildlife Protection Society of India (WPSI) The Wildlife Protection Society of India was founded in 1994 by Belinda Wright. WPSI's main aim has been to bring a new focus to the daunting task of tackling India's growing wildlife crisis. It does this by providing support and information to government authorities to combat poaching/illegal wildlife trade - particularly in wild tigers and shahtoosh. WPSI has provided training to more than 4000 forest and police officers have at workshops held in 16 states across India. WPSI Wildlife Crime Database has details of over 15,300 wildlife cases and is continuously updated with inputs from their countrywide network of investigators. This information plays a critical role in the development of new strategies to protect Indian wildlife. WPSI has assisted in the arrests of over 375 wildlife criminals and seizures of massive amounts of illegal wildlife products, particularly tiger parts. WPSI supports Conservation Projects for species as varied as the tiger, otter and sea turtle in the States of Assam, Chhattisgarh, Jharkhand, Orissa, Madhya Pradesh, Maharashtra, Uttarakhand and West Bengal. Endangered Species Day The United States Senate has declared May 21st as Endangered Species Day. The United Nations proclaimed May 22 as the International Day for Biological Diversity (IDB) to increase understanding and awareness of biodiversity issues. Internationally, 199 countries have signed an accord agreeing to create Biodiversity Action Plans to protect endangered and other threatened species. Many nations have laws that aim to provide protection: for example, by forbidding hunting, or by restricting land development or by creating sanctuaries. We would do well to remember that Emperor Ashoka (260–218 BCE) was perhaps the first ruler in history to advocate conservation measures for wildlife. Brief prepared by: Dr Sukanya Datta, 70 TRSA, NPL Colony, New Rajinder Nagar , New Delhi110060