Rats!!

[CharlesHarris]

“Mexican mouse trap” method of trapping rodents can be up-scaled for rats. Fill a large plastic drum or bucket to within 20cm of its top and float a handful sunflower seeds on the water. Place in a location where rodents can see the treat and readily jump in. Along a low wall, garden fencing or steps, or partially burying in your garden is good. Leave a few seeds around the bucket to attract rodents and increase their interest. Once they jump in, they can’t get out and will drown. The peeping of rodents in distress will attract others, which also jump in. Don’t over-fill with water because rats will lean in to feed instead of jumping in. Use a garden fork to empty. Don't handle dead rodents because they are disease vectors.

In a rodent infested area you will need multiple such traps to be emptied daily.