Half an Owl

Typical Christmas-had the usual health issues in the weeks leading up, so been a bit run down and the most energetic thing I've done in the last week has been putting the bins out. Decided to try and get a bit of exercise this afternoon since the rain had stopped.
There are potentially five owl species to be found in north east Herts at the moment, though Long Eared is a bit of a long shot. I know where birds have occasionally been seen flying , but there is no real chance of seeing them-I've never encountered one.
I decided to head up to Therfield in order to see the Shrike, some raptors and hopefully, being late afternoon an owl or two. Parked in Briar Lane and walked up the track, locating the pair of Kestrels and flushing a small covey of Red Legged Partridge. From the view point where this track meets Ickneild Way I saw a couple of Buzzards to the east and the occasional flock of Linnets, Yellowhammers and Skylarks flew over.
No sign of anything to the west so I went down the track to the conifers and scanned the lower fields for a while before returning. Not long after I reached the track junction I noticed a bird slowly flying behind trees near the farm. All I saw was a sandy wing with a dark carpal patch flick up and then down. Presuming Short Eared Owl I moved to try to get a better view but all that eventually emerged from the trees was a larger dark phase Buzzard. I assume the owl was hunting here as it was pretty sheltered-the wind was strong enough for the many Buzzards to hover.
Stuck it out until 1600 when the light was starting to get very bad and the wind was picking up even more but I did not see the owl again, so I left and drove home via Sandon where there was a chance of a Barn Owl in the headlights. All I encountered were three Muntjac in various spots.