Robbie The Cat


Feral Cat Management/TNR
Folding Drop Trap/Remote Control Trap

Lisa A. Pierson, DVM


Video of a drop trap in use.  (The reason why this cat marched under the trap right on cue was because he had been fed under it for the previous 2 weeks.)

December 26, 2006

This page will be an ongoing work-in-progress as I continue to modify a drop trap that I have designed. 

April 22, 2007 update:

I am currently building a Style 1 drop trap and am taking pictures as I go along.  Please see this page for a step-by-step pictorial.

August 28, 2009 update: 

I recently purchased a new remote control device to use on my Tomahawk traps.  While I have been very happy with my RC traps shown below, I do like this new unit also. It is easy to install and remove (unlike the one that I had a hobby shop guy make for me) but a bit of modifying may need to be done to allow for optimal fit onto the trap so as to have the door raised as much as possible.

This device will work, as is, with traps that have spring loaded doors (Tomahawk, Safeguard, and Havahart) but a receiver-mounting adapter will be needed for Tru-Catch traps which use hinged gravity doors.

Many people use the 'bottle and string' trick which is a very handy way to turn a trap into a RC trap.  However, I still prefer an electronic RC trap.

July 18, 2010 update:

Here is a link to another website that has more ideas on how to build a drop trap.  There are 3 links on this page.  Start with the "To See Pictures" link for an overview of the 4 different types of traps shown on this site.  Please note that the drop traps on this site are not as small (when folded down) as the ones that I designed.  Depending on your vehicle, this may be an important issue for you.

December 2011 update:

Please do not attempt to transfer a cat from a drop trap to a carrier with a swinging door. This is a recipe for disaster as cats often escape when attempting this.  You need to use a trap or a transfer cage with a sliding (guillotine) door.  Also, see the trap used in the video linked above.

February 2013 update:

For many years, I have used the Tomahawk 608 traps discussed below.  I have now switched to the 606NC which includes several design changes.  The catalog states that they are 30" long but mine is 32".  I hope that they have not made it shorter. 

You may not think that the extra 2" is important but it can be for long cats that elongate their body and step on the trip plate while outstretched.  I have had a couple of cats do this only to have the trap door hit their butt and not engage.  This is one reason why I refuse to use any trap that is shorter than 32".


Folding Drop Trap

Video of a drop trap in use.

For those of you who have ever used a drop trap, you know how valuable they can be.  Some cats just will not get into a conventional trap or have already been trapped and released for some reason and your only shot at getting these cats is to use a drop trap.

Unfortunately, most drop trap designs are either not collapsible or if they do collapse, it is not easy to do so.

In searching the web, I found Laura Burns' site here.  Laura was very helpful in giving me great ideas for an easy-to-collapse drop trap and if you want to skip the hassle of making one yourself, you can order one from Laura.  (4/07 Update:  Laura is pretty backlogged on her trap orders so you may want to roll up your sleeves and start making one.)  Laura's site also discusses how to use a drop trap which is outside the scope of this webpage.

**Important Note:  Laura and I have one 'creative difference of opinion' that I need to mention here.  I am a very strong believer that it is crucial to have bungee cords attached to the drop trap to the left and right of the door.  These bungee cords are then attached to the wire transfer trap to hold the two traps securely together.

When a cat bolts out of the drop trap they can do so at a very rapid speed.   They usually then turn around in a fraction of a second and can easily get out by pushing their way through any small gap between the two traps. People really underestimate a panicked feral cat's ability to muscle their way through a small gap!

I have heard of this happening on several occasions.  Even one cat escaping is one too many - especially if that one cat is the neighborhood 'baby machine' that you have been trying to get for the past many years.  These are the 'trap savvy' cats that you may very well not ever get back into any kind of a trap.

So please.....make sure that you have bungee cords attached to any drop trap that you use.  They are easy to attach using a eyescrews.  (picture below)


I will show two designs on this page.  Style 1 one is a breeze to use but is much more difficult to build.  See here for directions.  You have to be very precise when attaching a flat hinge to a round pipe but it is not as difficult as it sounds.  You just have to be careful to hold the drill firmly and keep it on track.  You can use wood if you prefer.  I just hate to sand and prefer the durability and longevity of PVC pipe.

Style 2 is not that hard to set up and may be just fine for people using it infrequently  but if you are a very active trapper and use a drop trap frequently, you may get a bit frustrated with the setting up and breaking down of Style 2.

Also, with regard to Style 2, my first trap had a flaw in the plastic garden fencing that I was using as the netting (the same netting shown in the picture) and a cat managed to rip its way out of the trap very quickly!  Needless to say, that was a huge disappointment since she was a park's local baby machine.  I ended up having to dart her with a tranquilizer dart.

The moral of that story is...use good netting.  I examined the flawed area and could see where the green plastic netting was very thin in one area. This just happened to be where the cat decided to pull on it with her claws.

Also, I would not want to use the green plastic fencing hundreds of times because the more times it is bent, the weaker it will get. But if you are a 'light' trapper, it may very well meet your needs.  

My Style 1 design is a variation of Laura's original folding trap but it varies from Laura's in that I use PVC pipe and Laura uses all wood.  Also, Laura's is open netting on all sides and the top whereas mine is solid on all four sides with netting just on the top.  Laura's is lighter than mine (~17# and mine is 26 - 30 lbs - depending on how much rebar I add for weight) and she uses a hinged platform to put a bucket of bricks or rocks on to keep the trap from moving which I would find inconvenient.

The trap that I use is 30 lbs and I would not want it any lighter -  as long as you are using a tail spacer as discussed in the Safety for the Cat section on the Building A Folding Drop Trap page.  The lighter the trap, the more apt the cat will be to get out of it. And...I tend to catch several cats at a time which would be a problem with a lighter trap with that many pounds of cats jumping around! (More on this issue below the pictures - July 18, 2010 update.)

Laura's trap and my Style 1 both collapse in seconds and are very compact and easy to carry and store.

Style 1:


Style 2:


April 21, 2007 - Quick notes:

1) The weight of the trap - I trap alone and do not want to have to break my neck running to the trap to hold it down.  I also want the option to be able to catch several cats at one time which I would not dare do with a lighter trap.  The trap that I use is 30 lbs.  

2) The dimensions of the trap -  I prefer to work with a larger trap - 44" x 44".  The bigger traps will usually clear the tails of most cats whereas the smaller traps will often come down on the tails.  (If you watch cats eat under these traps, it is not unusual for the tail to be past the perimeter of the trap.)  Also, the larger trap makes it much less likely that a cat will rapidly turn and get out from underneath it before the trap reaches the ground.

I have trapped 3 large adults at one time with my trap (30 lbs) and it held them well.  I have also trapped 5 cats and kittens at one time.

All traps (especially a 3' x 3' trap) should have a 5/8" gap between the trap and the ground to help protect the cat's tail should the trap drop on it.  See the directions page for pictures of what I use to create the gap.

July 18, 2010 update:

I want to reiterate - I will not use a light drop trap. I have seen too many cats get out from under them and I have no desire to ever have that happen to me.  My trap is 30 lbs and I am very happy with this weight. 

The president of our rescue group has one that I made for her that is 26 lbs and she has never lost a cat out of that one but she never pulls the rope with more than one cat under it. I do not want this kind of restriction since there are many times when my target cat is under the trap with another cat....that I may or may not want.  With a heavy trap, I can pull the rope on more than one cat with more confidence.....knowing that if Cat A is going up while Cat B is down low, the trap will not raise up resulting in Cat B getting out.

I often hear people comment that heavy traps are too dangerous.  But....the bottom line is that ANY trap can hurt a cat if the trapper is careless and pulls the rope at the wrong time.

Pay attention to when you pull the rope...and no cat or kitten will get hurt.

I have trapped hundreds of cats and kittens with my heavy trap. I have also made ~15 of these traps for the people at FixNation who loan them out to other trappers.  Nobody has ever reported injuring any cat or kitten with these heavy traps.  


Remote Control Trap

For the past several years, I have been doing 90% of my trapping with the drop trap and 2 remote control traps and I love the flexibility that these traps give me.  I have outfitted two of my Tomahawk #608 traps with the remote control equipment. 

Examples of how either a remote control trap or a drop trap can come in handy:

1) I can decide what order to catch the cats/kittens.  For instance, I was recently trapping a mom and her kittens.  The mother was exceptionally wary of the trap and I was concerned that her kittens would trigger it and that would be the end of my chances of getting least right away.  One kitten did enter the trap first - with the mother standing near the trap watching.  I chose not to trigger the trap.  The kitten then backed out and the mother went in at which time I triggered it.  I then got the kittens within the next hour....because they are just not as smart as their mother at this age.

2) I trap in areas where there are a lot of skunks, raccoons and opossums.  In one recently TNRd colony, the skunks outnumbered the cats 5 to 1.  It was a nightmare to deal with because the skunks were so bold that they would just march right into the traps.  Needless to say, this was a huge problem and every time I had to chase away (as gently as I could) an animal that I did not want to trap, the cats that I *did* want to catch would then just get more wary of the trap.  The RC trap has taken away the stress involved of constantly having to chase away the other critters.  Plus...I don't have the heart to chase them out of the trap since they are hungry too!

3)  Continuing with the above thought.....on several occasions, a bold skunk or raccoon, or an ear clipped cat has 'shown' a timid cat that the trap really is a good thing!  I have had many raccoons go into the trap and crunch dry food so loudly as to draw the cats closer.  The cats then sit there and watch with their little minds saying "hey...that food sounds mighty tasty in there!"  The coon, skunk, or cat will back out and then in goes the cat that has been watching.

One problem, however, is that the coons and skunks often drag the bowl out of the trap and you have to go and re-fill the bowl and put it back on the trap and re-bait the front part of the trap.  Some people use a bowl with a wire mesh on the top and I did this for awhile but then I felt sorry for the animals that were hungry.  It was bothering me to see them so frustrated.  Also, it has been nice when some cats that have already been TNRd go into the trap to eat.  Since I do withhold food from the colonies that I trap at, it is nice to see the ones that have already been altered at least have a chance at a good meal.

The RC trap uses 12 rechargeable batteries - 4 for the receiver and 8 for the transmitter.  I do not recommend using alkaline batteries since you really want a fresh charge on this unit prior to using it.  There is nothing worse than sitting for hours...only to have the cat that you are waiting for enter the trap and then nothing happens when you pull the trigger on the transmitter.  Fortunately, the trap can still be set manually very quickly.  I ran into a dead battery problem recently so I just quietly asked the cat to back out of the trap...went over and hooked it up manually....stepped back and the cat went right back in and triggered it.

This trap was not cheap.  In addition to the cost of the trap itself, fitting it with the RC set-up ran me ~$150 (parts and labor) and that did not include the batteries.  Rechargeable batteries are ~$3 each so that is another $36 and then the charger is ~$15. Of course if you are handy yourself or know someone who is familiar with RC products, you can cut the cost considerably.

One word of warning:  You MUST BE VERY PATIENT when using this trap.  Not once...but twice...I have triggered it a fraction too early and the cat was not quite in far enough and he/she got hit in the butt and the rest was history because he backed out.....what a disaster.  You MUST be very careful to make sure the cat has a paw on the trip plate and his head in the food bowl before triggering this trap otherwise they will get hit in the butt and they will back out....and probably never enter a trap again.

Remote Control Trap (Tomahawk model #608):


Plexiglass Liners in Traps

After many years of trapping I was going to scream if I had to line one more trap with newspaper or deal with anymore soggy paper that had been soaked in tuna oil.  All of my traps are now lined with Lexan with a plastic shower curtain for a white background.  No more trying to tape newspaper down in the trap on a windy night.  I can now either just wipe the trap out with a wet paper towel or hose it down.

When leaving cats overnight, be sure to place them on something absorbable since the urine will run off of the Lexan.  On a good note, the cat will at least not have to sit on soggy, urine-soaked newspaper all night. 

I only use 1 or 2 traps at a time so once a cat is trapped, it is transferred to a transfer cage with a guillotine door (see below) that has paper in it in case they urinate or defecate.  It is then easy to re-bait the trap and keep going instead of taking the time to re-line it with newspaper.

4/6/08 update:  I still love the fact that my traps are lined with Lexan but I have encountered several cats that have stepped over the trip plate....eaten the food....and then stepped back over the trip plate without triggering it.  (See second picture below for the remedy for the problem.)

Having the trip plate visible did not work well since the cats often stepped over it.


I added an extension to the trip plate.  The trip plate is 4 inches deep and I made the Lexan trip plate cover 6 inches deep so that there is no way that a cat can step over it.  Or so I thought....

9/1/09 update:  I have had a couple of cats manage to step over my 6" trip plate cover. I now put a double food bowl in the trap so they are less apt to try and step over the trip plate because, if the they do, they will step in the food.  As of February 2013 I have not had any cats step over the trip plate.


I always put the food as far back in the trap or bowl as possible and I use both canned and dry since many cats are dry food addicts.  I use Temptations treats which most cats love.



Transfer Cage (Tomahawk model # 306):

I love these transfer cages.  I take several of these into the field and just two 608s and my drop trap.  You must be very careful when transferring a cat to these cages.  Make sure that the trap and cage are well-braced together otherwise a cat can hit the end of the cage and separate the two.  If he doubles back quickly, he can escape through the gap.  This is especially true with small kittens if a small gap occurs.

I put the front end of the trap against my truck tire and then I have my leg bracing the back end of the transfer cage to make sure that they do not separate.

Be sure to have the cage somewhat covered so that the poor cat does not ram his face thinking that he can get to freedom.





Shelters for Feral Cat Colonies


Here is a link to ideas for building shelters for feral cats.

Updated July 2010

Partially updated February 2013

Lisa A. Pierson, DVM

Information on this site is for general informational purposes only and is provided without warranty or guarantee of any kind.   This site is not intended to replace professional advice from your own veterinarian and nothing on this site is intended as a medical diagnosis or treatment. Any questions about your animal's health should be directed to your veterinarian.


  Copyright 2011 All Rights Reserved.

Website design services provided by Stellar Media Group :: Affordable Website Solutions For Your Business