Arxiu d'etiquetes: critically endangered species

What is IUCN and its Red List?

A lot it is talked about endangered, critically endangered and vulnerable species. In fact, in this blog we have given some examples: Mediterranean monk seal is an example of a critically endangered species and Iberian lynx of an endangered species. But, which is the meaning of these names? Who is responsible of categorising them and how do they do it? Here, there are the answers. 

WHAT IS IUCN?

Have you ever seen this logo in some report or in Internet?

logo iucn uicn
International Union for Conservation of Nature logo (Pictrure: IUCN).

The International Union for Conservation of Nature (IUCN) is a union with more than 1,000 government and NGO member organizations, and about 11,000 scientists from 160 countries.

Its purpose is to preserve nature and, for this reason, it seeks to solve the most urgent environmental problems.

The IUCN is composed by 6 commissions, among which there is the Species Survival Commission (SSC), which have more than 10,000 volunteer experts from all over the world, distributed in different working groups.

The IUCN and the Species Survival Commission are the responsibles of elaborating the Red List. What is a Red List?

WHAT IS A RED LIST?

The red list of threatened species is an inventory of the the conservation state of plant, animal and fungi species. So, it evaluates the risk of extinction of a species in case no conservation actions are taken.

Lista Roja de la Flora Vascular Española 2008. (Imagen: Jolube).
Red List of Spanish Vascular Flora 2008. (Picture: Jolube).

This list is produced following objective criteria that permit to classify species in 8 threat categories, so that it is easier to compare different taxa. Let’s see them!

IUCN RED LIST CATEGORIES AND CRITERIA

REQUIREMENTS TO CATEGORISE TAXA

To use these criteria, some requirements have to be followed:

  • They can be applied to species and lower taxonomic levels.
  • They can only be applied to wild populations in their natural distribution and to populations resulting from benign introductions.
  • Criteria have to be applied to taxon whatever the level of conservation action affecting it.
  • The conservation status of a species doesn’t have to be necessarily the same in a global scale or a regional or national scale.

WHICH ARE THE IUCN CATEGORIES?

From less to more extinction risk, evaluated taxa can be classified in one of the following categories:

  • Least concern (LC): when a taxon cannot be classified in any of the following categories, it is said that there is a least concern for its conservation.
  • Near Threatened (NT): when a taxon cannot be classified in any of the following categories, but is close, it is said that is near threatened because in the near future it will possibly classified in some of them. The dwarf cassowary (Casuarius bennetti), a bird that could be the current velociraptor, has this category.
quandong, cassowary, eating, fruit
Cassowary eating quandongs, one of its favourite fruits (Picture: Christian Ziegler).
  • Vulnerable (VU): when a taxon is considered to be facing a high risk of extinction in the wild, it is classified as vulnerable. Two examples are whale shark and the basking shark, the two biggest fishes in the world and feed on plankton.
  • Endangered (EN): a taxon is endangered when faces a very high risk of extinction in the wild. An example is the Iberian lynx (Lynx pardinus).
  • Critically Endangered (CR): a taxon is critically endangered when faces an extremely high risk of extinction in the wild. An example, it is the Mediterranean monk seal (Monachus monachus).
  • Extinct in the Wild (EW): it means that only survives in cultivation, in captivity or as a naturalized population well outside the past range.
  • Extinct (EX): a taxon is extinct when there is no doubt that the last individual has died. An example is the thylacine.
Un dels pocs llops marsupials que es conserven taxidermitzats en el món. Museo nacional de Ciencias Naturales, Madrid. Foto: Mireia Querol
Thylacine was extinct by humans. Museo nacional de Ciencias Naturales, Madrid (Picture: Mireia Querol).

Vulnerable, Endangered and Critically endangered categories are those that show a threatened condition of the species. So, an endangered and a threatened species are not exactly the same.

Moreover, there are two other categories for those species not evaluated:

  • Data deficient (DD): when there is inadequate information to make an assessment of its risk of extinction.
  • Not evaluated (NE): when it has not yet been evaluated.

WHICH CRITERIA ARE USED FOR THREATENED CATEOGIRES?

5 are the criteria to evaluate the state of conservation of taxa:

  • Criterion A: Reduction in population size. It has to accomplish some of the following subcriteria (A1-A4), evaluating the reduction in the largest period, 10 years or 3 generations.
  Critically endangered Endangered Vulnerable
A1

Reduction in the past where the causes are reversible, understood and have ceased

90% or more 70% or more 50% or more
A2

Reduction in the past where the causes may no have ceased, may no be understood or may not be reversible

80% or more 50% or more 30% or more
A3

Reduction in the future (up to 100 years)

 

80% or more 50% or more 30% or more
A4

Reduction where the time period mus include both the past and the future (up to 100 years in the future) and where the causes may not have ceased, may not be understood or may not be reversible

80% or more 50% or more 30% or more
  • Criterion B: Geographic range either extent of occurrence or area of occupancy. Let’s see these concepts:
    • Extent of occurrence: when you draw a line that joints all the most external places where there is a taxon (and all the places are included), you find the extent of occurrence.
    • Area of occupancy: it refers to the area inside the extent of occurrence having into account that there is not present in all its extent of occurrence.
Dos ejemplos de la diferencia entre extensión de presencia y área de ocupación. (A) es la distribución espacial de dos especies, (B) es la delimitación de la extensión de presencia y (C) muestra una medida del área de ocupación (Foto: IUCN).
Two examples of the difference between extent of occurrence and area of occupancy. (A) is the spatial distribution of a species, (B) show  the extent of occurrence and (C) shows the area of occupancy (Picture: IUCN).
  Critically endangered Endangered Vulnerable
B1

Extent of occurrence

Less than 100 km2 Less than 5.000 km2 Less than 20.000 km2
B2

Area of occupancy

Less than 10 km2 Less than 500 km2 Les than 2.000 km2
  • Criterion C: Small size of the population and decline.
  Critically endangered Endangered Vulnerable
Number of mature individuals Less than 250

(and C1 and/or C2)

Less than 2.500

(and C1 and/or C2)

Less than 10.000

(and C1 and/or C2)

C1

Continuing decline

At least 25% in 3 years or 1 generation (up to 100 years) At least 20% in 5 years or 2 generations (up to 100 years) At least 10% in 10 years or 3 generations (up to 100 years)
C2

Continuing decline and at least one of the 3 conditions (2a.i, 2a.ii, 2b)

2a.i

Number of mature individuals in each subpopulation

At least 50 At least 250 At least 1.000
2a.ii

% of individuals in one subpopulation

90-100% 95-100% 100%
2b

Extreme fluctuations in the number of mature individuals

  • Criterion D: Very small population or restricted
  Critically endangered Endangered Vulnerable
Number of mature individuals Less than 250 Less than 2.500 Less than 10.000
  • Criterion E: Quantitative analysis 
  Critically endangered Endangered Vulnerable
E

Probability of extinction in the wild

At least 50% in 10 years or 3 generations (up to 100 years) At least 20% in 30 years or 5 generations (up to 100 years) At least 10% up to 100 years.

Despite there have to be evaluated all the criteria, with just one of them is enough to classify the species in the category.

The previous criteria are simplified because there are complementary conditions that have to be accomplished. For further details, read the document IUCN Red List Categories and Criteria.

REFERENCES

Difusió-anglès

Pangolin: poaching is condemning it to extinction

Neither the tiger or elephant or rhino: the most hunted mammals by humans are pangolins, to the point of critically threaten their survival as a species. Discover the only mammal with scales, its current condition and what can we do to prevent the extinction of all species of pangolin in the world.

WHAT IS A PANGOLIN?

manis tricuspis, pangolin, árbol, tree, trepando
Tree pangolin (Phataginus tricuspis). (Photo by Bart Wursten).

The name pangolin (also known as scaly anteater or trenggiling) includes 8 different species distributed by a variety of habitats (tropical rainforests, dry forests, savanna areas, cultivated fields…) in Africa and Asia. They measure between 90 cm and 1.65 m. They are the only family in the order Pholidota: although physically similar, armadillos, sloths and anteaters are not its relatives (order Xenarthra). Most are nocturnal, solitary and shy, so there are still many questions about their biology and behavior in the wild (they don’t usually survive captivity).

MORPHOLOGY

Pangolins are the only mammals with scales: they are made of keratin (like our nails) and give them a look like a pineapple or artichoke. Scales are very sharp and they can move them voluntarily. If pangolins feel threatened hiss and puff, curl into a ball leaving the scales exposed and secrete pestilential acids to ward off predators (tigers, lions, panthers and humans).

leon, leona, pangolin, bola, lion, defensa
An impenetrable defense even to a lioness. (Photo by Holly Cheese)

The claws allow them both climb as digging: terrestrial pangolins hide and breed in underground galleries and arboreal pangolins do the same in hollows on trees. The tail of the tree pangolin is prehensile to attach to the branches. In addition, pangolins are excellent swimmers.
They are mainly bipedal animals: forepaws are so large that force them to walk on its hind legs, with a maximum speed of 5 km/h. Watch a pangolin walking and feeding:

NUTRITION

Pangolin has no teeth and is unable to chew. It feeds on ants and termites, which locates with its powerful sense of smell (the view is underdeveloped) and catch them with its sticky and long tongue (may be longer than the body itself, up to 40 cm). The stones swallowed involuntarily and corneal structures of their stomach help them to crush the exoskeletons of insects. With its powerful claws destroy their nests to access them and avoid their attack plugging his ears and nostrils, besides having an armored eyelid. It is estimated that a pangolin can consume about 70 million insects per year, which makes them important regulators of the population of ants and termites.

lengua, pangolin, tongue
The tongue of the pangolin. (Photo by Wim Vorster).

REPRODUCTION

Pangolins can reproduce at any time of the year. After pregnancy (two to five months, depending on species) only one young is born (African species) or up to three (Asian species).

pangolin, hembra, female, mamas, breast, pecho, tetas
Female pangolin. (Photo by Scott Hurd)

The pangolin is born with soft scales, which begin to harden after two days. When after a month come out of the burrow, they travel on the tail of her mother and become independent at 3-4 months. Their lifespan is unknown, although in captivity an individual lived until 20 years old.

pangolin, baby, cría, zoo bali
Female with her baby in the tail. Bali zoo. (Photo by Firdia Lisnawati)

THREATS AND CONSERVATION

In addition to habitat destruction, the main threat that pangolins face is direct hunting for human consumption. Although there are international laws to protect them, it is estimated that about 100 000 pangolins are hunted annuallyGiven the defense strategy of this animal, poachers only have to catch them of the ground. Like other species, like sharks, the food market and traditional medicine are the main causes of directing the pangolin towards extinction.

pangolin, jaulas, tráfico ilega, illegal trade, bushmeat
Illegal trade in pangolin. (Photo by Soggydan Benenovitch).

WHY PANGOLINS ARE POACHED?

  • Bushmeat is considered a delicacy and an indicator of high social status in Vietnam and China. The pangolin fetus soup is sold as an elixir to increase virility and improve breast milk production. The price of bushmeat on the black market can reach $ 300 per kilo. The price of an individual can reach $ 1,000.
sopa, feto, soup, pangolin, feto, fetus
Pangolin fetus soup. (Photo by TRAFFIC).
  • Blood is sold as a tonic to improve health and as an aphrodisiac.
  • Scales can reach $ 3000 per kilo and are used for almost anything: to cure from acne to cancer. This belief is curious, considering that the scales have the same structure as our fingernails.
pangolín, china, medicina, medicine, tradicional, cura para el cáncer
Products of traditional Chinese medicine made of pangolin. (Photo by TRAFFIC).

All these purported medicinal and magical effects have no scientific basis, making yet more nonsense pangolin smuggling.

CONSERVATION

The population trend of all species of pangolin is declining in some cases to an alarming extent. The IUCN (International Union for the Conservation of Nature) Red List of Threatened Species classifies them as it follows:

RED LIS CATEGORIES IUCN
IUCN Red List categories. (Image from iucn.org)

Because of their status, IUCN restored in 2012 a group of specialists within the Species Survival Commission (SSC) dedicated to pangolins (Pangolin Specialist Group -PangolinSG-). Its main objective are do research to increase knowledge of pangolins, the threats they face and how they can be mitigated to facilitate preservation.

The conservation projects that are being carried out include campaigns to reduce the demand of bushmeat and pangolin scales and the tightening of laws. Still, the total ignorance of populations’ state and low survival in captivity for breeding makes it difficult to design strategies for their conservation.

WHAT CAN YOU DO FOR PANGOLIN?

  • Reject any product derived from this animal, either bushmeat, scales or “miracle” products for the cure of diseases. Read the labels of any traditional remedies, especially if they are from the Asian market, and recall that its hypothetical benefits have no scientific basis, so that you can rethink their use.
  • Share information. If you own new data on pangolins, photos or videos contact with PangolinSG to cooperate with the investigation. Talk about them in your immediate environment to raise awareness and publicize this fantastic single animal.
  • Do a PhD about pangolins. Lot of research on these species is still needed, so if you are a student and you are planning to do a PhD, you can collaborate with PangolinSG with your future research.
  • Become a PangolinSG volunteer. Get involved in the development and implementation of projects and conservation programs.
  • Make a financial donation so PangolinSG can continue its work.

In conclusion, more scientific research, a change of mind and protection policies are needed to prevent the pangolin become an example of extinct species at the hands of ours, as it is about to happen to white rhino.

REFERENCES

MIREIA QUEROL ALL YOU NEED IS BIOLOGY

Mediterranean Monk Seal: Until when will it survive?

In this post, we will do an approach to Mediterranean Monk Seal (Monachus monachus), a critically endangered species that, in fact, is the most endangered pinniped species in the world. Here, we are going to do a short historical review and we are going to talk about its natural history, its habitat and distribution, its threats and status and, finally, its conservation. 

INTRODUCTION

Mediterranean Monk Seal (Monachus monachus) is one of the three species included in the genus Monachus (Monk Seals). The other two species are Hawaiian Monk Seal (Monachus schauinslandi), which is critically endangered, and Caribbean Monk Seal (Monachus tropicalis), which is extinct.

mediterranean monk seal, monachus monachus
Mediterranean Monk Seal (Monachus monachus) (Photo: Sá, Wild Wonders of Europe)

Mediterranean Monk Seals were hunted for fur, oil and meat since Prehistory. Romans were responsible of an important decline, but thanks to the empire’ fall the animals were able to recover. More recently, the two world wars, the industrial revolution, the explosion of tourism and industrial fishing have produced the reduction and disappearance of the species in some regions.

MEDITERRANEAN MONK SEAL’S NATURAL HISTORY

When they are born, their length is 94 cm and their weight is 15-20 kg. Until weaning (at about 16-17 weeks), growth takes place fast. The pups’ pelt is soft and downy and the coat is black to dark brown, with a white patch in the belly.

Adult individuals have a length of 2.4 m (from nose to tail) and weigh 250-300 kg. Males are only slightly bigger than females. Juveniles and adults have very short hair. While adult males are black with a white patch in the belly, adult females are brown and grey with a lighter belly colouration. In any case, they can present more patches on the throat (males) and back (females).

Female individual of Mediterranean Monk Seal (Photo: Sá,
Female individual of Mediterranean Monk Seal (Photo: Sá, Wild Wonders of Europe)
Male individual of Mediterranean Monk Seal (Photo: Sá,
Male individual of Mediterranean Monk Seal (Photo: Sá, Wild Wonders of Europe)

Males and females reach sexual maturity between 5 and 6 years. After a gestation lasting 9-11 month, one pup is born (generally in autumn).

They feed on fish and cephalopods.

HABITAT AND DISTRIBUTION

This species’ habitat is inaccessible caves with underwater entrances. The truth is that in ancient times, they inhabit open beaches of sand and rocks. Mediterranean monk seals can be found in warm temperate, subtropical and tropical waters of the Mediterranean Sea and the east Atlantic Ocean.

Mediterranean Monk Seal habitat
Mediterranean Monk Seal habitat (Photo: Sá, Wild Wonders of Europe)
Mediterranean Monk Seal on beach
Mediterranean Monk Seal on beach (Photo: Hellio & Van Ingen)

In ancient times, the species’ distribution was bigger than now. While now they just are present only in the northeast Mediterranean and in the northeast Atlantic, long ago they were present in all through the Mediterranean Sea, Black Sea, Atlantic coast of Africa and some Atlantic islands.

Distribution map of Mediterranean Monk Seal (Monachus monachus) (Picture: TheAnimalFiles.com)
Distribution map of Mediterranean Monk Seal (Monachus monachus) (Picture: TheAnimalFiles.com)

STATUS AND THREATS

With just 350-450 individuals (maybe 550), the Mediterranean Monk Seal is one of the world’s most endangered marine mammals and is the most endangered pinniped species and it is described as critically endangered by IUCN.

Mediterranean Monk Seal is critically endangered, according to IUCN (Picture: IUCN).
Mediterranean Monk Seal is critically endangered, according to IUCN (Picture: IUCN).

The main threats against the species are:

  • Habitat degeneration and loss by development in the coast. The driving causes to this may be hunting, mass tourism, pleasure boats and diving. The result is that the caves occupied now are not adequate for their survival, so the recovery is only possible if they return to sandy beaches.
  • Killing them on purpose by fisherman and fish farm operators because they find it a nuisance that destroys their nets and steals their fish. In Greece, deliberate killing accounts for 43% of the deaths of adult and juvenile animals.
Deliberate killing of a Mediterranean Monk Seal (Monachus monachus) (Picture: A. Karamanlidis, MOm).
Deliberate killing of a Mediterranean Monk Seal (Monachus monachus) (Picture: E. Tounta, MOm).
  • Accidental entanglement in fishing gear. It is unknown if this has an important impact nowadays, but in the recent past it was and, in fact, it has played a significant role in the elimination of the species from some parts.
  • Decreased food availability due to overfishing. Malnourishment; susceptibility towards pathogens; affected growth, reproduction, juvenile survival and mortality rate and dispersion are the possible effects of this.
  • Unusual events: disease (like morbillivirus), toxic algae, rockslides, cave collapses or oil spills.
  • Pollution, maybe caused by organochlorine compounds used in pesticides.
  • Inbreeding depression, that results in reduced fecundity and pup survival. This factor is not a significant threat in the short term, but it can be a future threat because this causes reduced fertility, increased infant mortality and a distorted sex ratio.

CONSERVATION

Since 1970s, conservation measures have been developed, but the improvements are hardly seen. Conservation measures include:

  • Development of marine protected areas (MPA) in Madeira, Greece, Turkey and Cabo Blanco. In fact, what is necessary is a network of MPA.
  • Orphaned and hurt animals are rescued.
  • Educational programs.
  • Scientific investigation to identify its habitat areas.
  • International coordination of conservation activities.

On the other hand, ex situ conservation measures (like captive breeding and translocation) are not used because the species is so sensitive to human disturbance that it could be another threat.

REFERENCES

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