I came across the link above this morning, and it inspired me to have a go at it myself.
Fortunately, the two creatures I blended were sat in my pf - both with dark bg's, so it was just a matter of blending the two together,
enlarging the wing a bit for the squirrel size,
and finally adjusting the blue tit colours to match more closely with the squirrel.
Both original images were achieved with high speed flash.
Most importantly, what would this creature be called?