Has anybody collected hair samples from wild animals, with something other than barbed wire?

As far as I know, different kind of sticky tape are the most common method. I believe it is either used in combination with chemical attractants or placed on burrow entrances in burrowing mammals.

For example, slicker-type dog grooming brushes with stainless

steel wires

Glue traps - the types used for trapping rodents - can be used to collect hair samples from larger mammals. You can set a couple of glue traps on two opposing vertical surfaces and add an attractant like peanut butter between them to get the fox close enough to get a few hairs. This is a cheap and dirty method, but it does work.

Velcro (due to the little hooks) nailed onto a piece of wood can been utilised if you expect any rubbing behaviour from the foxes. I would be tempted to do a trial using glue, slicker brushes and velcro to see the most effective method. The thickness of the hair will also have a part to play in whether enough of the hair is caught and whether the skin tag is present/in tact or viable for genetic analysis.

I have a friend who used pieces of carpet with nails in them. 

There is a methodology to use raw wood sticks sprayed with something that atteacts the animals and makes them to rub on the stick.

It is used to track wild cats in Germany

Tha page is in German but you may be able to contact them and get a proper English description of the methodology

I would highly recommend this book:

Generally, sticky tapes, other adhesives, carpets with roof-nails, velcros, wire brushes, gun brushes can be good hair collecting surfaces!

I've used rodent glue traps (as Alexsandra already wrote) cut into small strips and put at the inerior entrance of cubby boxes with track plates.  The very sticky tape works well.  Here's a picture I found on-line if you're not familiar with cubby boxes http://www.for.gov.bc.ca/hts/risc/pubs/tebiodiv/marten/assets/maweml20-8.jpg

I was involved in checking some camera traps in Scotland wild cat project which is being looked upon by Dr. Roo Campbell who is also on researchgate. We rubbed a wooden stick by a metal brush to roughen it and put some catnip or any other attractant spray in the roughened portion. The rough portion makes the smell stay longer. We then put a velcro tape which will catch some fur. We also cut small portion from top to the middle in the sharp edges of the wood in a way that the cut portion do not fall off completely from the wood. These sharp edges will then, very efficiently, catch the fur. 

I might not have explained you properly so I would recommend you to contact Dr. Roo Campbell from Department of Zoology, University of Oxford. He is available on researchgate.

Some time ago we compared the efficency of nail-gun nails embedded in a piece of carpet vs velcro strips also in carpet squares.   For our site in the Neotropics the nail-gun carpet squares were more efficient.  You can check the paper here in researchgate:  https://www.researchgate.net/publication/229980652_HairTrap_Efficacy_for_Detecting_Mammalian_Carnivores_in_the_Tropics?ev=prf_pub

However, I am sure this will not hold for every single place and every mammal but the nail gun squares were really good at collecting gray fox hair.  But we even suggested doing a "hybrid" design.   As someone mentioned above there are multiple hair-collecting surfaces that have been used.   Most are cited/referenced in the island press book about survey methods for carnivores.   If safety of the foxes is your concern these nail-gun patches are perfect.   You just have to set them loosely and the nails move sideways when the animal rubs.   We did not had any single incident with harmed animals in our sampling.  Hope that helps.

I think you work on hairs of  wild animals at Electron microscopic level. there are a lot of article about  it.

Hi Anna,

I know the people at the Senckenberg institute use a non-invasive method for wildcats, see here:

Hope that helps.

Carpet with nail and 10 cm wide VELCRO the part with hooks. Look at "Non ivasive survey methods for carnivores." Robert A. Long et all. 2008, Chapter 6 "Hair Collection"

Just to add an extra comment to my previous answer.   Many people answering here (including myself) refer to the use of carpet with nails.  I just want to clarify that these nails are the ones used in nail guns.  Those come in large rolls joined by wire.  When they are "shot" the machine cuts those wires that end up bended in an angle and precisely the hairs are collected there when the animal rubs on the trap.  Normal, smooth nails will not work to collect hairs.   Hope the clarification is useful.

Dexter,  these break-away snares you mention seem quite interesting.  Just downloaded the paper you posted.   If these can be used to sample a single individual that opens the door to analyses not possible (or more difficult) than the other traps that normally sample several individuals.  This comment is quite relevant for the initial question that started this thread.   If separate sampling of individuals is what is needed then these traps seem the way to go.

On bat researches people are often using droppings. So you could also collect fox feces and analyze the hair in it.

I've collected wild dog/dingo hairs or epithelial cells for DNA analysis using two methods. One using a food lure placed on very fine (~600 grit) sandpaper, stapled to a 100 x 100 x 10mm piece of timber. A second very successful method was using a canid lure (Magna Glan and Canine Call worked for us) that elicited a rolling response. We placed a drop of this lure on a 1cm cube of sponge rubber on a sticky surface. Adhesive tape wrapped around a timber block (dimentions above) with sticky side out, sponge rubber/lure in the middle. Place these at scent stations or travel ways where foxes are likey to encounter them.