Interview: Merryl Gelling

A short introduction

I’ve worked in mammal ecology and research for nearly twenty years, in that time undertaking projects on a variety of native UK species from small mammals and bats to larger critters such as foxes and badgers, and general ecology to disease in mammals.  I undertook a Doctorate at the Wildlife Conservation Research Unit (WildCRU) at Oxford University on the health and welfare of water voles undergoing reintroduction, and since then have continued to conduct research with WildCRU, as well as working as an Ecological Consultant for protected mammal species.  I am the Chair for the Oxfordshire Mammal Group, and also sit on the council for the Mammal Society

What are your earliest memories of your passion for nature?

My grandmother owned a small piece of land in the Stiperstones, Shropshire and we used to go there for weekends when I was young.  We had complete freedom to run around the hills, climb trees and generally get stuck into everything.  I remember standing in a stream in my red wellies, carefully filling them with water with an old saucepan, and then crying when I couldn’t move as they were too heavy! I also used to catch gammarus with my hands and build little dams to watch how the water diverted around the stones.  

Watching foxes, squirrels and owls really captured my imagination, as did going on fungi hunts with my dad.  I also remember my mum being far from impressed when I found a lamb’s tail and bought it back for her!

What mammal-related topic has pricked up your ears recently?

For me, the most important mammal-related topic is rewilding, and the enormous potential this technique has for our environment.  

Can you explain further and whether you think this is relevant to UK mammals and Biodiversity?

We spend ridiculous amounts of money on human-induced issues such as flood defence, and yet we have the potential to reintroduce beavers who can undertake much of this work on our behalf, much more efficiently and much more cheaply that we could ever do.  

Beavers are a keystone species which has been historically lost from this country, again due to the impacts of humans wanting their fur and castoreum. However their engineering skills are extensive, and this would not only help to alleviate flooding downstream, but their dams help trap sediment which can improve water quality too.  

What’s not to love?  And it’s not just beavers.  We have the capability to reintroduce many of our native species wherever there is suitable habitat for that species.  

For instance, pine martens are thought to create an environment of fear for grey squirrels which could be advantageous to the recovery of our native red squirrel.  There may also be the potential for a similar effect with large predators including wolves in Scotland, as has been seen in Yellowstone National Park in the USA where the vegetation and biodiversity of entire valleys have improved substantially due to the reintroduction of this apex predator.  Obviously, I’m not saying let’s randomly release these animals all over, but I do think there is potential for carefully planned reintroductions to be very advantageous to us.


Pine marten

Finally otter numbers appear to be increasing, is this correct? And what effect do you think this will have on the non-native mink numbers?

Certainly, otter numbers in general are increasing, and otters are increasingly being spotted, not only in the wider countryside, but also quite at home in city centres.  This is a fantastic comeback for a species that had been pushed to the brink of survival in the UK due again to hunting, as well as pesticides and high pollution levels within our waterways.

When the increase in otter numbers was initially observed, there was a musing that these large mustelids might out-compete the more widespread and smaller invasive American mink.  


Water vole

This would have been a great news story for riparian mammal conservation – the return of the otter resulting in fewer American mink and thus safeguarding our native water vole populations.  Sadly the reality isn’t quite so cut-and-dried!  It now appears that otter do alter mink behaviour, but on a temporal  rather than spatial scale. This means that although mink occupy the same space as otters, they leave fewer obvious signs (scat and feeding remains), and tend to be more active around dusk and dawn, rather than being nocturnal as otter primarily are.  Of course there is individual variation and more research is required to understand this shift in behaviour more clearly, but unfortunately, it doesn’t currently appear that otters are having a substantial detrimental effect on mink numbers.

Thank you for your time Merryl!

Disclaimer: the views expressed by interviewees do not necessarily reflect those of The Mammal Next Door