been trying to trap coyotes with no success. we hear several packs almost nightly.

What do you recommend for bait? Would you recommend putting dog hair around the set? tried fish oil a few times and caught skunks and possums. What about coyote scent- figured they might come in to investigate a strange dog?

normally I only have a day to leave the traps (set one day and pull up and leave the next). Is that enough time to let the scent settle down? I find lots of scat in the area I am trying to trap.

First problem is you only have one night to trap. I've been trapping for a long time and first night catches on yotes are not the norm. Especially this time of year.

You say several packs. More than likely it's all one family unit, (depending on how big an area you're trapping). A family unit can have up to nine different dens a half mile apart. The dominate female will have one den for pupping. The dominate male will have his den. And any other females or young males that weren't kicked out will be around to help feed the dominant female when she has the pups.

I wouldn't use dog hair. This time of year yotes have already bred up, cleaned out dens and have laid out their territories. Best thing to use now is urine. In the spots you're finding scat make your sets using just urine. If you've got a male dog you can take him out and he will find all the places coyotes have marked, make a few sets where he marks.

how long is it ethical to leave a trap out between checking it this time of year.

I guess I'm concerned about catching a calf too. Had a cow back up and poop right on my set last week.

Can't leave a yote in a leg hold very long if you want more than a foot there when you check it.

Ethics is subjective. Law is not.

Per TPWD all devices used must be checked every 36 hours.

At least the coyote didn't crap on your set.

You might think this as crazy but I learned to do this a few years ago on our place and it works for my snares.
I will use the female urine and the poop on my snare sets. All of my snares are on fence lines. The poop I usually place about 10' either side of the hole on my side of the fence. The urine directly in front of the snare. I usually catch in 72 hours but you don't have that time but it may be something to try. I have even had times where I ran out of coyote urine, so I shot a rabbit, squeezed out it what I could and it worked with two coyotes caught the next 24 hrs. I don't claim to be expert by any means on snaring, but it's my preferred way other than using a 220 conni or a box trap for bobcats(heck of a lot of work for a cat, but effective). I'm just speaking from my experiences and there are more people a heck of a lot better than I at the footholds. I could never get them to work well for me.