Small black Alcid, smaller than nearby PIGU. Flew up from sea to back of Hermit Rock (south of Land's End Pale or white underside, small orange bill (didn't seem PAAU), white lines on face but only glimpse, Very pale eye. Photos. Getting too close to 2 BLOY and chased but still on back of rock. Finishing survey then will upload photos from home. Flies of circles rock.