Human interaction leading to increased inbreeding and isolation in animals

26 Jan 2018

Image: DADIKONNA/Shutterstock

New research into the effects of creeping urbanisation has found that many common animals on the fringes of cities are becoming more inbred.

Sightings of wild animals in suburban areas have become common, but these animals’ need to stray from their comfort zone is leading to increased – and troubling – complications in their genetics.

New research conducted by a team of 100 researchers, including one from University College Cork (UCC), found that mammals such as the fox, red deer and hare are becoming increasingly hemmed in by human-dominated landscapes.

This is having potentially disastrous results for the animals, resulting in them becoming more isolated, inbred and therefore more likely to be prone to extinction.

To find this, the research team (led by Dr Marlee Tucker of the Senckenberg Biodiversity and Climate Research Centre and Goethe University, Frankfurt) measured 57 different types of land mammals.

During the research, it became clear that the affected animals – ranging from wild boars to elephants – travel distances between two and three-times shorter in human-modified landscapes than they do in the wild.

Their movement was tracked using a GPS device that recorded each animal’s location every hour for a period of at least two months.

From an Irish perspective, UCC researcher and co-author on the paper Dr Adam Kane said that animals familiar to the island can be blocked by roads, rivers and Luas lines, and emphasises the need to make our human habitats more permeable for animals to move through.

Not just physical barriers

“The importance of the geographical movement of animals in the wild has long been documented. It is necessary for the animals to find food, water, mates and new habitats to live in,” said Kane.

However, another co-author of the paper, Dr Thomas Mueller said that it isn’t just physical barriers that cause problems, but psychological ones, too.

“In some of these areas there might be more food available so that animals do not need to cover such large distances,” Mueller said.

Aside from issues with inbreeding, cutting short the natural movement of animals can lead to the rapid spread of disease if a sick individual doesn’t move far.

Also, the movement of animals allows seed dispersal from plants which in turn feeds into the natural cycle of the environment.

As lead researcher, Tucker said: “It is important that animals move, because in moving they carry out important ecological functions like transporting nutrients and seeds between different areas.”

Colm Gorey was a senior journalist with Silicon Republic