I’ve recently begun backyard trapping. I started with some small mouse traps, a Victor and a Doc250. I’ve been using Peanut Butter as bait, with Vinegar (“apparently” repels birds). The traps have only been in for a little while (a month), with them being moved around a bit, based on possible rodent location. About 17 days after installing the Victor, I caught a huge mouse. The next day, a male sparrow. Unfortunately, this morning when checking the traps, I found a female blackbird inside the Doc250, 2 days after installed, which was rather upsetting. I am wondering if anyone has any working strategies to lower bycatch as best they can?
The huge mouse that you trapped was probably a juvenile rat. Mice will visit new traps very quickly, but rats are cautious (neophobic).
Is the Victor trap inside a tunnel? If it is, but the tunnel doesn’t have a wire mesh baffle, it would be a good idea to create one. An entrance 7x7cm should exclude most birds, but remember to file down the mesh so that rodents won’t get poked or scratched by the wire
Something that you could do to reduce the chances of birds being trapped, is to lure and arm your traps at dusk, when most birds have shut down for the day. Check your trap(s) in the morning and disarm them.
If you have a shed and/or garage, they are both good potential trapping sites that birds should have trouble entering.
I have a doc250 in the back garden to pick up any rats, hogs or Mustilids that pass by – normally I use a piece of 100mm dia bamboo – about 150mm long placed in front of the mesh entry. It stops birds as well as hogs – but if I see a hog leaving his scat around the lawn – I remove the bamboo – I usually get the hog within a few days – but unfortunately I get the odd black bird or thrush. I use a block of fat and an egg in the doc250. A piece of plastic pipe should work well.