How do I get started with trapping American mink? Q&A
N.B. These notes are intended to provide brief answers to the most commonly asked questions. More detailed advice and guidance is available on the WRT website.
Yes, mink trapping is entirely legal in England, Wales and Scotland. Once a mink has been caught, though, it is illegal to release it alive. The animal should be humanely dispatched. The only mink in Britain are American mink, imported many decades ago for fur farming. The highly endangered European mink has never occurred here, so there is no risk of misidentification.
It is legal to use both live traps and kill traps. The disadvantage of kill traps is that they trap indiscriminately, and ‘non-target’ creatures may be killed. Live traps simply restrain the animal, allowing non-target creatures to be released unharmed. The disadvantage of live traps is that either they must be physically checked every day, or they must be fitted with a Remote Monitoring Device (RMD) which will inform the trapper(s) when the trap door has closed.
Waterlife Recovery Trust (WRT) strongly recommends the use of cage traps (the most common form of live trap) fitted with an RMD. We term this combination a ‘smart trap’. These offer effective, humane, targeted removal of American mink.
The most humane and rapid way to dispatch a mink is to shoot it through the head. Death is immediate and painless. WRT recommends the use of a .22 air rifle. Those under the Firearm Certificate power threshold can be freely bought, held and used in England and Wales with no license, but the situation is different in Scotland. Here you must obtain an Air Weapon Certificate or Air Weapon Permit from the Police, or you can apply to add an air weapon to an existing Firearm or Shotgun Certificate.
A mink carcass is a potential source of valuable information. Whenever possible, WRT and its partners aim to collect, examine and sample every one captured or found dead, anxious to learn its age, sex, reproductive status, where it came from and which other mink it’s related to (both from genetics). We would be very grateful if you could inform WRT via the website if you catch a mink. We will respond quickly. At minimum, we would ask you to send us a photo of the animal and, if possible, a small piece of the ear for genetics analysis (a postage paid envelope will be supplied). If you live in or near East Anglia, we will probably arrange to collect your mink. If not, once you have photographed the animal and taken a bit of tissue, the animal can be returned to nature, either buried or placed under a hedge, say, where scavengers and natural processes will quickly recycle it, just as would happen if the mink had died in the wild.
Mink are semi-aquatic, and spend most of their time in or near water. The vast majority live on streams, rivers, canals, ponds and lakes, but many in west Scotland, especially, are equally at home on coastal fringes. Your chances of catching a mink are consequently greatly enhanced if you place your trap on or near water.
Mink love to climb on a floating platform. A trap placed on a raft is therefore likely to be visited by any passing mink, and is also much less likely to catch terrestrial animals such as rabbits, hedgehogs, squirrels and stoats, all of which would demand a trap visit. For these reasons, almost all WRT traps are situated on a raft tethered to the bank of a waterway or water body. In a small minority of cases (e.g. when a river is in spate or a raft might form an obstruction) a trap situated on the bank may be a better option, and a raft would certainly not be a good option in marine waters.
These exceptions aside, WRT recommends placing a trap on a raft. Fortunately, a suitable raft, with a custom-designed tunnel to accommodate a cage trap, can be easily purchased. The raft of choice for WRT at present is made by Filcris Ltd. It is made of recycled plastic, does not shed polystyrene balls into the environment, and will last many, many years. We term a custom mink raft equipped with a smart mink trap as a ‘smart mink raft’ or ‘smart raft’. This is the standard equipment unit of WRT.
A Remote Monitoring Device is simply an electronic box that is attached to a trap, senses when the trap door closes, and then immediately initiates a process which leads to one or more nominated people being informed of the event by email and phone text message. The RMD doesn’t link to the trapper(s) directly, but via a virtual web-based ‘portal’. Users register their RMDs on the portal, and tell it which RMD (each has a unique number) is situated in which location. This may sound complicated, but RMDs are extremely reliable once set up, and they save huge amounts of time and mileage. Crucially, they allow a trap to be active 24/7 without the need for daily trap visits. They are used by Government agencies and are, if truth be told, more reliable than many of the people who elect to trap their traps daily. They don’t suffer from hangovers, flat tyres, medical emergencies or waning dedication in the face of hundreds of visits to an empty trap.
That said, the RMD can do no more than attempt to alert people to the fact that a trap needs an urgent visit. If no-one notices the alert, then there’s a chance that an animal in the trap will die a lingering death, and that must never be allowed to happen. For this reason, the many hundreds of traps operated by WRT and its partners across 10 counties are all managed by a small number of local people on the ground, but are also under the watchful eye of a Coordinator, whose job it is to ensure that every single trap alert leads to a prompt trap visit. A Coordinator can oversee the use of more than a hundred traps, and may never visit any of them, but acts as a guardian angel, using phone/email/whatsapp/text message to ensure a visit, and not resting until one has been made and the RMD has been reset. We strongly recommend that every trap is provided cover in this way, and for this reason it makes best sense for people to collaborate, sharing a Coordinator, who can be local or can live in another country. Good communication is the key here.
The most basic mink trap is just that – a trap. A cheap cage trap can be bought for £35, and will last for years, but will require a physical check at least once a day when set, and preferably more often than that. WRT uses a robust, high-quality trap that is rather more expensive (made by Perdix Ltd at about £50 including VAT and delivery). A single raft will cost about £140 inc VAT and delivery, the price reducing somewhat for larger orders. RMDs vary in price, but the model we recommend is made by Remoti Ltd and they cost about £125 inc VAT, delivery and 12 months of use of the Remoti web portal. Thereafter, there’s a monthly fee of £2+VAT per unit.
In rough terms, then, the basic elements of a good quality RMD-equipped trap on a raft (as used by WRT and partners) costs about £315, to which must be added various ancillary expenses (RMD batteries, cable ties, tethering rope and posts for securing to). A round figure of £330 will cover all this.
For an experienced person, with tools and ancillaries at hand, It takes about an hour to get the RMD working, the trap tested and the raft assembled. Instructions are available on the WRT website. Further time will be required to get set up on the RMD web portal, and to register the RMDs. Once everything is ready, the smart raft can be deployed. You’ll need tethering rope (we use 6mm diameter polypropylene) and mooring stakes, unless there are existing posts or handy trees in the right spot.
Mink are resident and kill prey year-round. Catches tend to be higher during the juvenile dispersal period Aug-Oct and during the mating season of Jan-Apr, but mink can be caught at any time of year. The best day to start trapping is therefore today, and traps should remain active continuously, year-round if at all possible. Every mink removed saves the lives of hundreds or thousands of native creatures, so delay is costly.
This all depends on your circumstances. Someone with a short stretch of waterway at the end of their garden will need no more than one smart raft. But a fishing club or a nature reserve would most likely need 2-6, and most Internal Drainage Boards would need 10-30 units in order to clear their waterways of mink. Across East Anglia, an average density of one permanently-active trap per 18 sq km of land has been enough to remove mink, but areas with fewer waterways might need fewer traps. If traps are not permanently active, a much higher density than this would be needed.
A trap placed at a good site in an area with little or no mink trapping history may catch ten mink in its first year of operation, five mink in year two and thereafter 0-2 mink annually. Mink are territorial, so they never occur in the densities of rats, and their numbers will be rapidly diminished if traps are kept active year-round. In areas with little mink habitat or a history of trapping, a trap may not catch a single mink in its lifetime, but that trap is still extremely valuable in telling us that mink are few and far between at that site. It’s worth bearing in mind that the aim is to remove mink catches to zero, everywhere.
The best strategy is to spread your traps more-or-less evenly along the available waterway margin at first, and then be ready to perhaps move some of them after a few months as you learn about mink and other creatures on your patch. Some sites will prove to be productive, others less so. On wide rivers, it pays to have traps on both margins.
Until now, mink trapping in Britain has always been open-ended, simply because new mink have been available to replace those caught on a particular river or lake system. This depressing situation is now changing, however. Coordinated, collaborative trapping on a landscape scale in eastern England has now been shown to remove mink entirely, so re-invasion cannot happen if the trapped area is large enough.
In any area with a network of continuously active mink traps, mink can be reduced by over 70% year-on-year. This means that fewer than 1% will remain after 4 years, and by this time reproduction should cease (just because boy does not meet girl in the short mating window in early spring).
The Waterlife Recovery East partnership has not yet been in existence for 5 years, but discussions are already underway to consider where traps can be picked up because they have caught no mink in a long time and now have no realistic prospect of ever catching one. It will be unsafe to remove all traps until mink immigration has completely ceased, but after 5 years it is highly likely that trapping effort can be safely reduced.