Beaver benefits: Why we all should give a dam about beavers

Beavers are critical to healthy ecosystems. Their dam building improves water quality and provides homes for countless species.

Incredible sightings of desirable and highly sought after mammal species seen when out and about with wildlife enthusiasts have become standard over the years. Many of these sighting in the immediate vicinity of beaver sites.

That is why we think it is important to describe a broader picture of this fascinating rodent that we keep encountering on our trips in the Bieszczady Mountains of Poland. Moreover, in order to coexist with these furry dam builders, it is important that people understand them.

Size, general appearance and behavior of the beaver

Beavers (both the Eurasian and Canadian) are one of the largest rodents species in the world. Their weight is around 11–30 kg, and usually, their head-to-body length is 80–100 cm with a 25–50 cm long tail.

Their extremely large incisor teeth are very special as the front face of these teeth have a tougher coating than the rear. So as the rear face wears down, it creates a very sharp edge, used to chew through solid wood.

Being semi-aquatic mammals, beavers spend great portions of their lives in the water. Their large paddle-like tails and webbed hind feet are used to propel themselves through water, making them agile and perfect swimmers.

Typical are their sudden slapping flat tails on the water surface as a warning sign. Often loud enough to scare off nearby predators, startle intruders and alert other beavers of potential danger.

The current status of the furry dam builder

Unfortunaterly the species was hunted to near-extinction for  its fur. Also its castoreum (a bitter strong-smelling creamy orange-brown substance that consists of the dried perineal glands of the beaver and their secretion) was used especially by perfumers.

In modern days, the beaver is listed as least concern on the IUCN Red List after the species was reintroduced to much of its former range and today beavers can be found all across the continent.

One of nature’s most fascinating architects

The fact that beavers are equipped with special tools allowing them incredible construction abilities working tirelessly to still moving water. Their ultimate goal is to create a personal little beaver oasis: a pond with a number of ditches that branch off to wherever they wish to go. Their special teeth, and strong swimming ability, allow them to build dams and homes for themselves.

The more open  water they create, means safer travels and very important: it offers underwater entrances into their homes aka famous beaver lodges. Despite beavers sometimes tunnelling into river banks, in general and most often, their homes (lodges) are dome shaped structures along the shore, or in the water. Their structures are purely functional as they drop piles of sticks and mud in seemingly random places. This without clear entrances or exits.

From treetrunk to treetrunk

They gnaw and chew down trees, drag them to the water, and then float them into large piles, filling the gaps to create watertight walls. These walls of wood and mud are also known as beaver dams. It makes them some of the world’s most skilled ecosystem engineers, with an incredible ability to create new wetlands, restore native woodland, and improve habitats for a wide range of species.

Keystone species in Bieszczady but also else where

Beaver dams can be quite large, weaving through swamps and wetlands. Unfortunately, beavers are not aware of the wants and needs of people. They remain vigilant in their efforts to make a comfy beaver home. In the Bieszcady mountains of Poland,  these beaver abilities, as extraordinary as they are, does not  lead to conflict with another species of great builders, humans. The fact that Bieszczady is a sparsely populated area, means that beavers can do their thing to the fullest. Wherever possible, they take the opportunity to bend a biotope to their will. Sometimes these beaver areas are no more than small ponds near roads, but often also biotopes that, over the years, have only become more beautiful and varied. The richer, surrounding landscape also attracts other wildlife.

It is important to know that beaver ponds are not just good for the beavers creating them, but can benefit other animals as well. Still or slow moving water is good for biodiversity, creating mini-habitats that shelter plants and animals in the beginning stages of life. A calm pond can also provide animals with good hunting grounds. Beavers are a ‘keystone’ species of wetland habitats, meaning that are wide array of other species, from fish and frogs; to insects and birds, are impacted by their presence in the ecosystem.

In Bieszczady large dams often become a natural land bridge that other animals in the area use to stay dry while moving about. Others in turn use the biotope to rest, forage or just loiter around. The list of species that we have seen over the years near beaver areas is gradually becoming impressively long: brown bear, wolf, eurasian lynx, wildcat, roe deer, red deer, european bison, red fox, raccoon dog, eurasian otter, polecat, beech and pine marten. This both during the day and during the night.

The use of a thermal camera has been a further positive development in our Polish guiding work over the years.

2023 reports

Both reports of the first out of two trips in April can be found in the REPORTS section: one in Dutch; the other in English. We tried to write a realistic and moody picture of the journey with special attention to the better observations. But also written in such a way that people should not expect a safari trip as animals in Bieszczady are far from habituated. We try to avoid a dry summary of the known daily pattern of meals alternated with numbers of spotted animals. We wish you a lot of reading pleasure.

The link to the report in English:

The link to the report in Dutch:


Again a sincere thank you to a number of people, in random order, for their contribution to this news item:

John Wright for proofreading the English text. Jillis Roos, Pete Ramsey and Mark Kaptein for making their visual material (pics and video footage) available. As the same with Thomas Geelen for editing some pictures and for editing the video footage for  both video compilations.