Bromadiolone, the active ingredient in Contrac, accumulates in the liver to inhibit and steadily decrease Vitamin K levels in the blood. This prevents the blood from being able to clot and will eventually lead to death. So the majority of the active is absorbed by the blood stream, and although very small trace amounts could potentially be found in the feces, it wouldn't be consistent. There will definitely be some of the waxy substance and the dye in it, but it wouldn't be enough to cause damage or be of any concern.
Per the Contrac All Weather Blox product label: "This product must be used in and within 100 feet of man-made structures constructed in a manner so as to be vulnerable to commensal rodent invasions and/or to harboring or attracting rodent infestations. Examples of such structures include homes and other permanent or temporary residences, food processing facilities, industrial and commercial buildings, trash receptacles, agricultural and public buildings, transport vehicles (ships, trains, aircraft), docks and port or terminal buildings and related structures around and associated with these sites. Fence and perimeter baiting, beyond 100 feet from a structure as defined above, is prohibited." Also, keep in mind that rodenticides like Contrac must always be used in appropriate bait stations and cannot be thrown loosely in the open.
Since squirrels are in the same family as rats/mice, it is possible the bait matrix in the Contrac All-Weather Blox Rodenticide could be attractive to flying squirrels also. While rodenticides can be used indoors for rodent control, we typically do not recommend baiting for rodents indoors as the bait can draw insects and can also keep drawing the rodents into the home. We would recommend using the Contrac Blox in the tamper resistant bait stations outside the home around the structure. Inside the home, you can use Detour Rodent Repellent to make the attic less appealing to rodents and squirrels and use Rodent Snap Traps or Glue Boards to catch unwanted guests in your attic.
If you know where the squirrels are entering you can use an Tomahawk One Way Door Excluder where they are entering the attic. This will allow the squirrells to exit through the hole, but not get back in. Exclusion Methods with Copper Mesh or Xcluder Wire are great ways to seal up holes to keep mice, rats and squirrels out.
Yes, by law, Contrac Blox Rodenticide must be applied inside of tamper-resistant bait stations.
Unfortunately, we do not sell vitamin K1. It is readily available from any vet.
Contrac All-Weather Blox Rodenticide should never be placed outside of a tamper resistant, locking bait station. Additionally, the bait stations should be within 50 feet of a structure. It is made with food grade additives and will be highly attractive to unintended wildlife and pets. If you find bait blocks loose on your property, you should dispose of them. They contain waxes and additives to help the bait stay fresh for a longer period of time, so it’s possible it may withstand elements of weather for a length of time. If you are concerned your dog may have eaten some, we recommend you contact your vet ASAP, as there is an antidote available that can be given soon after ingestion that can reverse the effects of the Contrac.
Contrac All-Weather Blox Rodenticide must be used in tamper resistance baits stations by law when used outside so it cannot be just placed out at night in the open around a bird feeder. The best thing to do with birds is to stop feeding them and use the bait in stations until the rodents are under control, otherwise you are providing a food source that they are more familar with which makes them less likely to go for the bait. After rodents consume the bait they are going to die wherever they die. To prevent this happening inside you should seal up all cracks and crevices that allow them access inside.
We have some guides below that can help as well:
https://www.domyown.com/how-to-get-rid-of-rats-a-525.html
https://www.domyown.com/rat-prevention-guide-a-526.html
If there are pieces of Contrac All-Weather Blox Rodenticide in the grass, these should be picked up and removed immediately. The only way to be sure the area is safe to remove the pieces. To prevent pieces being removed from stations that hold the bait is to check them frequently and remove any broken or small pieces to keep rodents from carrying them off and leaving where non target animals/people can come across them.
Contrac All-Weather Blox Rodenticide is not labeled for opossums. In fact, there are no baits on the market that are made for opossums. In most cases, you will have to trap the opossum using a cage trap. Local ordinances in your community will dictate how to dispose of the trapped animal. You can learn more about opossum control by reading our article Opossum Control. By law, all rodenticide baits including Contrac must be applied in tamper-resistant bait stations.
The Contrac All-Weather Blox Rodenticide label states the following: This product must be used in and within 100 feet of man-made structures constructed in a manner so as to be vulnerable to commensal rodent invasions and/or to harboring or attracting rodent infestations
Fastrac Blox can ship to California. Please keep in mind there is no antidote available for non-targeted animals like there was with the Contrac All-Weather Blox Rodenticide.
Contrac All-Weather Blox Rodenticide is not labeled for coyotes. We do offer coyote traps.
You should not put Contrac Blox or any other pesticides inside air vents or other similar systems within your home. Rodenticides must be secured in bait stations or otherwise in areas that are inaccessible to people, pets, and non-target animals. If rodenticide is not secured, then the rodents can hoard the bait and may move it to a location where it becomes accessible to non-target animals. We recommend using traps for rats that may be indoors. We have more tips on how to eliminate rats from your home in this guide.
While there should be no issue using the Contrac All-Weather Blox Rodenticide and First Strike in the same station (meaning they won't interact with each other), it would be better to use one at a time and rotate between them every 4-6 months instead to prevent resistance buildup to either.
Contrac All-Weather Blox Rodenticide is only labeled for Norway Rats, Roof Rats, House Mice, Meadow Voles. It is not labeled for opossums. Please look at our Opossum Control Page for options on trapping.
We cannot ship Contrac All-Weather Blox Rodenticide to California but Ditrac is an alternative that can be used.
Freezing temperatures will not negatively impact Contrac All-Weather Blox Rodenticide when used in stations. When in storage you should keep the pail in a cool dry place away from extreme temperatures.
Yes, the Contrac Blox can be cut shorter to fit station if needed. Be sure you are wearing chemical resistant gloves while handling the rodent bait and tamper resistant bait stations.
Fastrac All-Weather Blox has the faster kill of the two, but Contrac All-Weather Blox Rodenticide has an antidote if needed. Fastrac All-Weather Blox is a neurotoxin and there is no antidote if children or pets consume the bait. If you have children or pets, it is recommended that you use Contrac All-Weather Blox Rodenticide since every doctor and vet has the antidote, which is Vitamin K1.
Unfortunately, neither the Contrac All-Weather Blox Rodenticide or DeTour Gel for Rodents would be recommended to treat for opossums on the property. Contrac All Weather Blox are only labeled for Norway Rats, Roof Rats, House Mice, Meadow Voles and DeTour Gel for Rodents is intended for rats only, there is no documentation showing effectiveness of these products on other animals such as opossums.
Please take a moment to review our Opossum Removal Guide here for more information and helpful tips.
