QUESTION:

I've got one for you. Today I was checking my rat bait stations and found a baby opossum inside one of them. I have been putting Fastrac rat bait in the stations regularly for the past few weeks and the baits have been disappearing at a record rate. Instead of the regular gnaw marks that are normally found when rats are feeding, I have seen big chunks of baits bitten off both inside and outside of the bait box. Should I continue to bait the box or would you recommend the use of a live cat trap. The area where my stations are located is in a false ceiling in a government office full of professional women. What do I do?

ANSWER:

Several things come to mind that may factor in your decision here. First is that these rodent baits are labeled to be used where they are "inaccessible" to children, pets, and wildlife. Normally we could consider the false ceiling in a large office to be such an inaccessible area, but since the opossum obviously have found their way into it this cannot apply, and to continue placing bait meant for rats and mice in this area could be inappropriate. There also are no poisons labeled for opossum, so allowing them to continue feeding on it would be off-label. And, if these opossum have been feeding on the bait, as you indicate, for the past few weeks, I would expect some of them to be dying from the bait. If this does occur with a large animal like this you could end up with a VERY serious problem with odors and flies.

You also say that you are finding chunks of the bait bitten off both inside the station and outside, and you probably mean that the chunks are being found outside after being carried out by the animal. If instead you are placing the bait outside the station this probably should stop, and all baits be only within the TP station. Somehow I have a hard time picturing a full grown opossum getting into a bait station meant for rats. If the mother is foraging with her young then perhaps only the smallest of the young made it into the station, as you have found. The mother might be making some effort to work at that station to get to the bait if she smells it, but you should see evidence of this by the station being tipped over or moved. I would think it a little odd for the young to be out foraging on their own if they are still small enough to fit into the station, but this is an unknown to me.

I definitely would discontinue the baiting for now and go to an intensive trapping program to live trap these animals. Along with this you need to perform a very careful inspection of the exterior of this building to see where these animals are gaining access. While they are good climbers I would not consider them capable of climbing vertical walls, so it is most likely they either are finding access near ground level or making their way to the roof. If there are any trees adjacent to the building ensure all branches are cut back at least 6 feet from the roof line. Other openings, it would seem, should be pretty large to admit a full grown opossum. These are opportunistic feeders that eat almost anything, so bait the traps with something with a nice, tempting odor, such as bacon, fish, fruit, etc.

Another concern is the disposal of the animals when you trap them. I do not believe there are any constraints against killing them, but you may want to check with your local wildlife agency on this. Some U.S. states consider them to be "fur-bearing" animals and require a permit to trap or kill them. Releasing them can be tricky legally, as some regions do not allow them to be released just any old place. You may be required to release them "on site", which emphasizes the need to perform good exclusion, or to get a permit to take them off site to release them in a natural area.

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