Pyrenean desman

The Pyrenean desman (Galemys pyrenaicus), also known as the Iberian desman or trumpet rat, is a species of small semiaquatic mammal in the family Talpidae. It lives in the mountain ranges of the Pyrenees and mountainous areas of the northwestern Iberian Peninsula, mainly in the Cantabrian Mountains and the Sistema Central. You can find it in four European countries: Andorra, Spain, France, and Portugal.

This animal looks a bit like a mix of different creatures. It has a strong tail for swimming, like the brown rat, strong claws for digging, like the European mole, and a long snout for catching small creatures, like the common shrew. Its funny trunk-like snout gives it the name “trumpet rat.” The Pyrenean desman doesn't see very well and uses its sense of touch to find its way and food. Its snout has special feelings at the base and tiny sensing organs at the tip.

The desman eats mainly tiny water creatures such as larvae of stoneflies, caddisflies, and mayflies. It lives in clean, fast-flowing streams and lakes and comes out mostly at night, staying away from people. Because it needs clean water, it is a good sign of how healthy the water is. Sadly, building things like dams and changing rivers hurts its home, and since 2021, it has been listed as Endangered by the International Union for Conservation of Nature.

Description

The Pyrenean desman is a small, semi-aquatic animal. It measures around 25 cm (9.8 in) in length, with more than half of that being its tail. It weighs between 50 to 60 g (2.1 oz).

It has webbed hind feet, which helps it swim well. Its fur is grey-brown and helps keep it dry in water. The Pyrenean desman uses its long, flexible nose, called a proboscis, to feel around for food underwater. It also has special senses to help it navigate its environment. Its feces are small, twisted pellets that it leaves on rocks above the water.

Habitat and distribution

The Pyrenean desman lives in the mountains of the Pyrenees and parts of northwestern Spain and Portugal. It is found near rivers and their smaller streams in countries like France, Spain, Portugal, and Andorra. These rivers often flow through rocky areas and have clear, moving water.

This animal prefers clean, oxygen-rich streams and lakes. It needs water that stays full year-round and avoids places with dirty or still water. The Pyrenean desman is a good swimmer and climber, making its home in these special water places. It is often used to show how healthy the water is because it needs very clean conditions to survive.

Life cycle

The Pyrenean desman lives alone or in pairs and has a home range of several hundred metres along rivers. Females usually cover about 250 metres, while males cover about 450 metres. When pairs share the same area, they can use up to 800 metres but often stay in separate spots. Both males and females leave scent marks.

These animals spend time in water and on land. They are mostly active at night, spending about eight hours in water between 11 pm and 5 am. During the day, they rest for about half the day. In winter, they may be active for short periods during the day.

They swim well and can climb small waterfalls using their long claws. On land, they move slowly and often rest to clean their fur. They eat small water creatures like larvae of mayflies, stoneflies, and caddisflies, which they find using their sensitive senses. They also sometimes eat land insects like spiders and grasshoppers.

Main predators include the Eurasian otter, common buzzard, northern pike, stoat, tawny owl, white stork, grey heron, and black-crowned night heron. The invasive American mink also poses a threat in Spain. Domestic dogs and cats can also hunt them.

Taxonomy

The Pyrenean desman lives in the mountains of the Pyrenees and northwestern Iberian Peninsula. It can be found in Andorra, Spain, France, and Portugal.

The type locality is in France, described as "in the mountains near Tarbes", in the Hautes-Pyrénées department. The holotype—the preserved specimen on which the original species description was based—is housed at the Muséum national d'histoire naturelle in Paris.

In 1829, the species was reassigned to the genus Galemys by the German naturalist Johann Jakob Kaup, who designated it as the type species of the genus.

The Pyrenean desman is an insectivorous mammal belonging to the family Talpidae, subfamily Desmaninae, and is the sole extant species in the genus Galemys. Its closest living relative, and the only other surviving desmanine, is the larger Russian desman (Desmana moschata), which occurs in the drainage basins of the Volga, Ural, and Don rivers.

Two subspecies of the Pyrenean desman are recognised:

• Galemys pyrenaicus pyrenaicus (Geoffroy Saint-Hilaire, 1811)
• Galemys pyrenaicus rufulus (Graells, 1897)

Paleontology

Fossil evidence shows that several types of desmans lived across Europe from the Urals to the Atlantic coast, from about 15 million years ago to around 5.3 million years ago. Today, there are only two types of desmans left. The Russian desman looks more like the early types than the Pyrenean desman. Scientists think the two types of desmans split apart about 10 million years ago.

The type of desman called Galemys first appeared about 2.6 million years ago. Over time, its home range moved from central and western Europe to the southwestern area, the Iberian Peninsula. This area’s mountains were not covered by ice during the last big cold periods, so it was a safe place for the desmans to live. This shows that Galemys was already good at living in fast-moving mountain waters a long time ago.

Anthropogenic threats

The Pyrenean desman lives in special mountain streams that are disappearing because people are changing these areas more and more. Building things like roads and dams breaks up their homes, which is the biggest problem for them. For the desman to survive in France and the Iberian Peninsula, we need to protect and fix their natural homes.

Many human activities in the early 2000s have hurt these animals. Dams and other water projects change the flow and temperature of rivers. Barriers in rivers split up their paths. Building things along riverbanks and draining wet areas take away their homes. Pollution also harms the water where they live. These changes affect the tiny insects that the desman eats.

In France, laws say there must be enough water flow below dams, but scientists debate if this is enough. Studies near the Lac de Bious-Artigues dam and a paper mill at Eycheil found no big differences in water quality above and below these places. So, dams alone may not threaten the desman's food. But sudden big releases of water from reservoirs can stir up mud and make the water unclear, which hurts the desman and other water animals.

A study in the Pyrenees National Park looked at desman numbers before and after reinforcing riverbanks with rocks. After the work, many places where desmans rested disappeared. Desmans need burrows or natural holes to rest. Since the 2000s, people have built fake wooden burrows with moss and leaves in some streams to give them new resting spots.

Desmans can accidentally get stuck in pipes or grates at water intakes used by farms, factories, and homes.

Water pollution can change the temperature, muddiness, acidity, or air in the water, which can reduce the insect larvae the desman eats.

Some people used to think desmans ate fish and would kill them, but this was a mistake. Now, people are learning more about desmans and trying to help them. For example, they pick up old fishing lines to prevent desmans from getting caught.

Desmans mostly sleep during the day, so tourists usually don’t bother them. But some water sports that step on stream beds can hurt the tiny animals desmans need to eat. This might cause desmans to disappear from busy places like the Sierra de Guara in Spain.

Climate change might also affect desmans. Models show that by 2070–2099, warmer temperatures could make desmans leave some areas, like northern Portugal and parts of Spain, and only stay in very high, cool places like the Cantabrian Mountains and the Pyrenees. Some scientists suggest helping desmans move to new areas in the future.

Conservation

The Pyrenean desman, a small water-loving mammal, has faced tough times recently. In the 2020s, scientists found that its numbers were dropping fast. By 2021, it was listed as an endangered species because its population had fallen by almost half since 2011.

In France, the desman has almost vanished from 60% of the rivers it used to live in. The worst drops happened in the western parts, but the eastern Pyrenees still have more stable groups. In Spain and Portugal, the desman is also considered vulnerable or critically endangered. In Andorra, studies show big drops in numbers too.

Countries like France, Spain, Portugal, and Andorra have made laws to protect the desman and its homes. They have also started special projects to help the desman recover, like cleaning up rivers and making safe spots for them to live. These efforts also help other animals that share the same rivers.

Human relations

For many years, people in the Pyrenees mountains had many old stories about the Pyrenean desman, but scientists knew very little about it. Some people thought the desman ate fish like trout, but this was not true. Others said they saw desmans resting near haystacks, but these stories were more like fun local tales than facts.

Scientists first learned about the desman in the early 1800s. It was hard to study because desmans are shy and hard to keep alive in captivity. Real scientific work in their natural homes only started in the 1980s. Even today, there is still much to learn about these animals.

In recent years, the desman has become more famous. Schools and tourists are learning about it to help protect the Pyrenees' nature. It is now a special symbol of the mountains, like the brown bear and the chamois. There are even comic books and statues about the desman, and it was even photographed for a big project by National Geographic.