May 11 2006. A floatation in aerated sea water experiment on a Cormorant tail feather stranded at Chalkwell on January 3rd reached an interesting event this morning with the water temperature returning to 51° F (10° C). The feather of Phalacrocorax carbo (L.) with a black melanin stained rachis and vane (155 x 18 mm) beyond the white quill or calamus (total length 195 mm) has remained intact and having tilted to roughly 45 degrees from the initial stable angel around ten degrees on May 23, reached the vertical calamus-up orientation today. Some 16 mm of the calamus was above the water. This intact rotation after an additional 147 days in cool sea water contrasts with similarly tested small terrestrial bird feathers which have gone vertical and sunk within 70.2 days (the record held by a predated starling feather of 75 mm length and 15 mm width). Most were nearly submerged when they became vertical. Larger ones disintegrated while floating. Probably the Cormorant feather is adapted to resist decay in sea water and in this respect it resembles both the black and the white parts of gull feathers floated earlier and later, with and without drying. However, the Cormorant feather differs from these gull feathers in having a denser and actually still better articulated vane causing the calamus to initially tilt-up slightly and now to rotate long before the overall density is the same as sea water. Densities are difficult to measure on feathers due to surface tension and instantaneous partial flooding but one can measure the percentage submerged at the tipping point.