Why reintroducing the pine marten might be a disaster

Our wildlife and countryside has changed enormously in my lifetime, with the population of some species of fur, feather, fin and fauna crashing while others have boomed beyond recognition. My father and grandfather both said the same, so perhaps this is just a typical old man’s moaning about the inevitable changes that ‘progress’ brings.  

Humankind has added and removed species to our islands for more than 2,000 years. The Romans bought us the brown hare, pheasants, fallow deer and the domestic cat. They are blamed, too, for the introduction of the black rat, which indirectly wiped out much of the human population by carrying a flea-borne plague.

The introduction of certain species have had a negative or even devastating effect, prime examples being the grey squirrel and our native red, and the mink with our water voles. The red squirrel has been eradicated from many areas because of a disease carried by the greys, and water voles are simply decimated by a predator that evolution had not prepared them for.  

Introduced creatures such as the rabbit have been with us for so long that many of our predators have become almost dependent upon them. My grandfather said that a good year for rabbits was a good year for game; most predators will take a rabbit in preference to anything else. 

 

Invasion

If we take introduced species to mean existing and breeding in the wild, the list is staggering. Some 15 species of mammal have invaded our shores, including four of our six deer and five fitting the description of predators. There are also birds, reptiles, amphibians, fish, molluscs, crustaceans, a vast number of insects and plants, not least of all Japanese knotweed, which costs the country millions of pounds each year.

This is only part of the story. We also have reintroductions of native, or once native, birds and animals that either disappeared from areas or from the UK entirely. The wild boar is a prime example. Others, such as the European lynx and wolf, have not returned, despite calls for their reintroduction. But is a return of such animals justified?

When a creature has been with us for so long that populations of other species become unthreatened or even dependent upon their presence, they are naturalised and others have adapted or evolved to accept them. It is the very opposite side of this ‘evolution’ that is the reason against reintroducing or widening the range of certain other creatures which, for whatever reason, have disappeared from our shores. 

Is it right to reintroduce predator species when the last thing their prey needs is another attack upon their declining populations?

It is a simple fact that many prey species of birds are in serious decline, freefall even. Of the 70 species of bird currently on the red list of concern, all but five may be classed as prey species. Strictly speaking, anything killing another creature is a predator, but I am excluding invertebrate ‘meals’, and those five predators are all ground-nesting. There are a further 103 birds of amber concern and eight species have disappeared as breeding birds altogether.

Where mammals are concerned, one in four species is in danger of extinction and 45% require urgent action. The picture is similar for amphibians. By far the greatest loss is, of course, insects, the basic food for so many species. Decimated by agricultural sprays and habitat loss, their demise has had a devastating effect upon so many living creatures. 

 

Mayhem

I have witnessed first-hand the reintroduction of an apex predator, the pine marten. Already causing mayhem in Scotland — where they are blamed at least in part for the demise of the capercaillie — they were reintroduced in an area of Kerry that I know well. Initially the whole valley was delighted to see them, they became extremely tame and I managed to get one drinking from a saucer of milk only yards from me. 

I caught one in a mink trap set along the river; it simply smashed the trap and escaped. They are immensely powerful creatures. 

The locals’ delight disappeared as all chickens, turkeys and even some lambs were taken. People have noticed over the past few years how the population of songbirds has waned and, most unforgivable of all, the once plentiful red squirrels are now a rare sight. Somehow, martens killed all the great tit chicks inside the small hole of a standard nest box high on a pole in my garden. There is no tree they cannot climb.

There are now calls for the pine marten to be reintroduced to the areas that they once inhabited, but back then the world was a vastly different place. Modern farming, concrete encroachment and an imbalance of predators were not issues. Habitat and food were natural and plentiful. We did not have a situation where 70 species of our birds were in danger of extinction, with a further 103 in severe decline. 

Most of our bat species are in freefall and they are a favoured food in the barns that the pine martens inhabit. Dormice, whose populations have declined by 52% since 1995, are easy prey but are one of the mammals that will suffer as this supreme predator expands in number and range.

Is it right to add yet another predator to areas where so many creatures are in real trouble? We need to look after what we have before adding to the list of their problems. Pine martens may have had their range reduced, but domestic/feral cats, mink and rats were never meant to be here; foxes and badgers thrive upon the larder we keep fully stocked for them and corvid numbers are simply like a fire out of control. 

Why would we even think about adding to the demise of so many more vulnerable birds and mammals?