This thread is a condensed summary of information found in numerous other threads, and all of it designed to help concerned BYC growers deal with rat their infestations. It is divided into three parts: 1. Know your rat 2. Rat Proofing 3. Elimination Each of these sections will also include some older historic videos produced by the CDC (Center for disease control). While these videos are dated in appearance, the information presented in them remains valid today and will be helpful to anyone seeking to rid themselves of rats. Know Your Rat Before you can do much about your rat problem, you need to know which one of the two major species of rats you have. Behaviors are different, and thus control methods are also different. Brown rats will make up the vast majority of the rats BYC growers will need to deal with. 1. Brown Rats https://en.wikipedia.org/wiki/Brown_rat 2. Black Rats https://en.wikipedia.org/wiki/Black_rat This video explains the nature of Brown Rats......whether your colony is small or large.....this is what you are up against: Rat Proofing When it comes to rat proofing a structure, most growers will be stunned, bordering on overwhelmed, as to the length a person must go to create a physical structure that is rat proof. Rats are that good. Here are two resources to study: https://wildlife.unl.edu/pdfs/rodent-proof-consturction-structural.pdf A few key items to remember: First is the size of an opening a rat can slip through......no holes larger than an inch, so in general, be thinking 1/2" hardware cloth over any openings. Second, if you are really up against it, metal and cement are your friends. Cement floors and foundations to create barriers of exclusion, along with metal siding or metal clad doors and jams. Study the video to see what a rat can chew through and all the ways then can gain entry and the difficulty of exclusion becomes clearer. Of all the things to study, this rat proofing video is one of the best to follow. Elimination Some growers find that exclusion via rat proofing efforts is all that is needed to work for them. That means elimination of all access to food, water and shelter within and around the coop. Theory being you can starve them out and they will move on. For others, even that doesn't work. If rat proofing doesn't work, and elimination is still your goal, then you are faced with killing your rats by one means or another. Trapping, shooting, dogs, cats, etc. are all methods found in this arena, as is the use of poison bait blocks. A lot of folks find the latter to be objectionable, but experience has proven that unless and until a grower is willing to use them, their rat problem may never go away. At best, it may be diminished, but never eliminated. Some resources towards elimination: http://nwdistrict.ifas.ufl.edu/phag/2016/01/29/controlling-rats-and-mice-around-the-farm/ http://npic.orst.edu/factsheets/rodenticides.pdf When considering the use of one particular product, it may be helpful to print out this summary sheet, then look at the product label to ID what the active ingredient is, then decide if that is what you want to use, or perhaps you would prefer to use something else. Then there is this video: Note the issue of rat control using traps, etc. is addressed within the first minute of the video. That is as true today as it was then, and for the same reasons. Trapping alone will barely dent the population of a rat colony. They are too smart for that to work. Traps can be used to monitor populations, but is not an effective method of control when used alone. Beyond that, the baits used are different today than are shown in the video, but the process is the same, including the use of multiple forms of bait blocks, and for the same reasons. And you can use game cameras to monitor activity (instead of tracking powder), but the process is the same. Lastly, if and when you decide to use poison bait blocks, it should be a given that you are going to do so as safely as possible so as to avoid the danger of any primary or secondary poisoning of unintended targets. This means any poisons will be served up from secure bait boxes that only the rats and mice can gain entry into. As noted in the video, if allowed to, it is the nature of rats to drag a bait off from where you left it, and in doing so, leave it exposed to non targeted species.......like perhaps your birds. So proper bait stations use methods to pin the bait in place so it has to be eaten where you left it. Secondary poisoning is a real concern of some, but can be mitigated to a large extent by how things are done, and if a real concern, you can select baits that pose very low risk of secondary poisoning. Baits like Terad3 from Bell Labs. As for which brands of poison baits to use, there are a lot of products to chose from. What you use will be up to you, and will be based on local availability, price, and your experience as to which products your rats will accept. A good place to start is with Bell Labs products, which are used by many professional exterminators. These products may not be available locally as others are, but can be ordered from Amazon and perhaps ebay. Disadvantage is they come in larger quantities than most need, thus the expense factor runs high. Their bait boxes are very good, however, and those can be ordered in small quantities. https://www.belllabs.com/products As for how much to buy, if you have a large infestation, don't be shy about how much to get. They will go through more than you might think. Lastly, know that once you have had rats, you are always subject to having more, so it becomes critical that you monitor for activity, and that goes on pretty much forever. Hope this information helps.