One or more persons on a front porch or other viewing location close by (although the range of engagement can be increased... IMHO a person should be within 100yds) One Rifle w/some type of solid rest for steadying the Semi-Automatic or Bolt Action weapon chambered in .17HMR(IMHO) & your choice of magnification in a rifle scope mounted with a quick release cam action fastener onto a picatinny type rail for daytime engagements if any are currently un-threatened, and have any diurnal habits or boldly unabashed tendencies you may have noticed about their habits previously, before they're observed, then engaged by an operator posted at a site which you've pre-determined as being your projectile's barrel disembarking point and they wise up because of a miss, multiple critters out at the same time and only one get's engaged, or they just are aware and cautious from that point on cause that's how they roll in your body of water... now only coming out at night.
So then, at that point... I'll change the tactics I've attempted to use previously on them and immediately go about about swapping out my quick release mounted normal daytime glass lensed scope for my ATN THOR LT 3-6x Thermal Imaging Scope and get closer if I want, walk around the edge, change my shooting nest location, or do nothing at all other than sit and wait on darkness or another muskrat to come out before darkness arrives, because the thermal scopes work just fine in the daylight as well as at night. I have "#zero" 'skrats in my ponds and more enjoyed time with friends or relatives sitting and conversing or even fishing quietly than I would've ever had if I were intstead... completely go around the edge & w(rap) my riparian zone with an expensive 4-6"(baby surge) or 6-12"(surge stone) sized rip-rap rock, that I'd been forced to purchase then have to more than likely hand place it for the finished look moving those HEAVY 6-12" surge stone" type of rock by stacking them in their final resting area 1 at a time... muskrats are WAYYY lighter in weight and (IMHO) About 100% more fun & challenging to stack than "RIFF RAFF" ROCKS as I've heard it called by more that a few. Maybe now at least you know where the name rip rap came from. I hope I haven't offended anyone and lowering the total number of the heard decibel's from the rifle's report(pew-pew) upon engagement is an optional piece equipment which normally increases your overall success rate pretty substantially... but I've only heard such talk of..and have not ever witnessed it's positive or negative results firsthand for myself...