Feb 22
Bermuda cave amphipod (<em>Pseudoniphargus grandimanus</em>)

Bermuda cave amphipod (Pseudoniphargus grandimanus)

Species: Bermuda cave amphipod (Pseudoniphargus grandimanus)

Status: Critically Endangered (CR)

Interesting Fact: Juvenile Bermuda cave amphipods are found far closer to the shore than adults.

More information:

The Bermuda cave amphipod is a colourless, eyeless amphipod that lacks a rostrum (a forward-projecting spine found between the eyes of most crustaceans). The upper lip is broadly rounded and the lower lip has large inner lobes. Male Bermuda cave amphipods are known to reach lengths of 6.5 to 8 millimetres.

The Bermuda cave amphipod is found in anchialine caves. These are coastal caves that are flooded with seawater via subterranean connections with the ocean. This species has been found in water of varying levels of salt concentration throughout a wide variety of anchialine limestone cave and groundwater habitats. Juvenile Bermuda cave amphipods are found far closer to the sea coast than adults, typically just 11 to 180 metres away, compared to 147 to 853 metres for adults.

Large adults, but notably no specimens carrying eggs, have been found further inland from the sea coast than juveniles. This could indicate a dependence on coastal marine habitats for reproduction, and that juveniles may migrate inland to mature.

The Bermuda cave amphipod is endemic to Bermuda, as its name suggests. Is has been recorded from wells, waterworks and cave waters in Hamilton, St George’s, Devonshire, Paget, Smith’s and Warwick Parishes in Bermuda. Caves in which it has been found include Church, Wonderland, Admiral’s and Government Quarry Caves.


Find out more about the Bermuda cave amphipod at Anchialine Caves and Cave Fauna of the World.

See images of the Bermuda cave amphipod on ARKive.

Phoebe Shaw Stewart, ARKive Text Author


Feb 8
Café marron flowers and leaves

Café marron (Ramosmania rodriguesii)

Species: Café marron (Ramosmania rodriguesii)

Status: Critically Endangered (CR)

Interesting Fact:

On sending his pupils out to explore for rare and interesting plants, a school teacher on the island of Rodrigues in 1980 was astounded when one of his students returned with a fresh cutting of a plant believed to be extinct.

More information:

The café marron had last been seen in the 1940s, and is now known from just a single wild individual on the island of Rodrigues. The café marron grows as a shrub or small tree, with oppositely arranged leaves. The sweetly scented, hermaphroditic flowers are greenish-yellow at first, but become pure white at maturity.

The café marron cannot self-fertilise. This prevents plants from inbreeding, while promoting out-crossing, which increases the genetic vigour of offspring. However, the inability to self-fertilise becomes somewhat less advantageous when a plant’s global population is reduced to a single individual.

It was probably a combination of introduced herbivores, invasive alien plants, and habitat loss that decimated the café marron population. Owing to the unprecedented level of scientific interest that surrounded the little plant in the aftermath of its rediscovery, local people became convinced of the plant’s medicinal properties. Consequently, there was a period before the erection of multiple fences, and even the installation of a guard, when people were intent on removing branches, twigs and leaves from the hapless plant.

Relatively soon after the rediscovery of the café marron, cuttings from the surviving plant were sent to Kew Gardens in England. In 2003, a major breakthrough was made, resulting in the production of a small number of viable seeds. Since then, several seeds have been successfully germinated at a nursery on Rodrigues, with the aim of eventually re-establishing a wild population on the island.


Find out more about the café marron at Kew Gardens and the Mauritian Wildlife Foundation.

See images of the café marron on ARKive.

Phoebe Shaw Stewart, ARKive Text Author

Jan 25
European mink (Mustela lutreola)

European mink (Mustela lutreola)

Species: European mink (Mustela lutreola)

Status: Critically Endangered (CR)

Interesting Fact: The European mink is one of Europe’s most endangered mammals.

More information:

Weighing up to a maximum of 1kg, the European mink is the smaller relative of the American mink (Neovison vison). A distinctive mark of white around the upper and lower lips of the European mink can help to distinguish between the two species.

This species is mainly nocturnal, hunting and feeding at night on a variety of prey including water voles, birds, frogs, molluscs, crabs, fish and insects. It is able to hunt both on land and in water across large home ranges of up to 15km of river. Partly webbed feet and a thick, water-repellent undercoat mean that the European mink is well suited to its semi-aquatic lifestyle.

A century ago the European mink could be found throughout the European continent, but its population is thought to have since declined by over 90%.  In 2011, the IUCN upgraded the status of the European mink from Endangered (EN) to Critically Endangered (CR) due to ongoing population decline.

This severe decline is a result of various threats, including habitat loss, commercial trapping for fur, competition from the introduced American mink and accidental mortality through pest control, poisoning and vehicle collisions. The European mink is also susceptible to Aleutian disease, a highly contagious virus that causes an often lethal infection.

Captive breeding programmes are underway for this species in an attempt to successfully establish new European mink populations. Further research is being undertaken to assess the viability of captive breeding as a technique for the conservation of this species. In Spain and France, the populations of European mink seem to be suffering from inbreeding, a problem which could be addressed by the introduction of new, captive-bred individuals.

The European mink is legally protected in all the countries in which it occurs.


Find out more about the European mink at the IUCN Red List and the World Association of Zoos and Aquariums.

See images of the European mink on ARKive.

Phoebe Shaw Stewart, ARKive Text Author

Jan 4
European eel swimming

European eel (Anguilla anguilla)

Species: European eel (Anguilla anguilla)

Status: Critically Endangered (CR)

Interesting Fact: The first three years of the European eel’s life are spent drifting in the ocean as a larva.

More information:

The European eel has a long, narrow body, with a continuous dorsal, anal and tail fin. The colour of adults depends on the age of the individual, but usually ranges from brown or black to olive-green, with yellowish bellies. Some adults may be silvery, and young European eels are transparent and are known as ‘glass eels’.

The European eel has a fascinating life cycle, breeding in the sea and migrating to freshwater in order to grow, before returning to the sea to spawn. It is thought that all European eels spawn in the Sargasso Sea. The larvae drift in the plankton for up to three years, and are carried by the Gulf Stream towards the coasts of Europe. They then spend between 6 and 20 years in freshwater, before migrating back towards the sea on dark, moonless and stormy nights to mate. European eels can live for up to 85 years.

The European eel is found in the rivers of the North Atlantic, Baltic and Mediterranean Seas. It is also seen along European coasts from the Black Sea to the White Sea in Russia.

The population of the European eel is threatened at present, and eel stocks have declined in recent years. There is currently very little scientific knowledge of this species and the threats it faces. However, pollution, overfishing, habitat degradation, parasite infection and changes in climate have all been suggested as potential causes of the European eel’s decline.

The European Union is currently funding research that aims to halt the decline of the European eel population.


Find out more about the European eel at the Zoological Society of London and the Sustainable Eel Group.

See images and videos of the European eel on ARKive.

Phoebe Shaw Stewart, ARKive Text Author


Nov 16
Image of white-bellied heron

White-bellied heron (Ardea insignis)


Species: White-bellied heron (Ardean insignis)

Status: Critically Endangered (CR)

Interesting Fact: Also known as the imperial heron, the white-bellied heron is the second largest species of heron in the world, exceeded in size only by the Goliath heron.

More information:

The white-bellied heron is a large, long-necked species, named for its white underbelly and wing linings. It has a blackish head topped with a pale plume of feathers, and a brownish-grey body. The most outstanding feature of the white-bellied heron is its massive pointed bill, which measures about 15 to 18 cm in length.

Although primarily a solitary bird with a large territory, during the winter months the white-bellied heron may fly up to 30 kilometres to join other members of its species.

The white-bellied heron is resident in Southeast Asia, having been seen in Bangladesh and surrounding countries. It is now believed to be extinct in Nepal.

The white-bellied heron favours mature forests, a habitat that has been at risk from deforestation for over a century. It is also under threat from the fragmentation and degradation of its wetland habitats through pollution, over-exploitation of resources and the rapid growth of aquatic vegetation due to leaching of artificial fertilisers. In addition, the white-bellied heron is vulnerable to disturbance and habitat degradation as a result of agricultural expansion, human settlements and poaching, as well as overfishing.

The white-bellied heron population is extremely small, at fewer than 250 mature individuals, and is rapidly declining, putting this species at severe risk of extinction.

In May 2011, the first white-bellied heron chick to be bred in captivity hatched, as a result of a project by The Royal Society for the Protection of Nature (RSPN) in Bhutan. There have been reported sightings of the white-bellied heron in protected areas of north-eastern India, and there are more protected areas proposed both in India and Bhutan which might lead to an increase in population size.


Find out more about the white-bellied heron at BirdLife International and Heron Conservation.

See images of the white-bellied heron on ARKive.


Phoebe Shaw Stewart, ARKive Text Author


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