Flamborough Head is England's most northerly outcrop of the Late Cretaceous Chalk Group and is home to the highest chalk sea cliffs and the only mainland gannet colony in the UK. In recognition of these latter claims, the RSPB has established the very popular and successful Bempton Cliffs reserve which sees around half a million seabirds gather here between March and October to raise a family on towering cliffs overlooking the North Sea. Perhaps the most popular attraction is the puffin colony, though each visitor will have his or her own favourite.

The headland, though founded on solid chalk, has a blanket of Quaternary deposits, mainly till and stratified gravels. In places such as Danes Dyke, these deposits fill deep ravines cut into the chalk bedrock and provide a completely different habitat from the cliffs at Bempton. A walk from the car park to the beach in early May will take you through woodland where the sometimes harsh calls of seabirds give way to the more melodious sounds of the blackcap, wren and robin and the 'tapping' of woodpeckers.

The ornithologist notes that the northern side of Flamborough Head hosts most, if not all, of the breeding sites for sea birds such as gannet, guillemot, razorbill and puffin. The geologist notes that the Chalk of the northern side of the headland is different from that on the southern side and that there is a significant variation in the influence of the Quaternary "blanket". So this talk will try to combine these observations and look for possible geological explanations to variations in bird distribution. In doing so I will throw in some questions based on observation: Do guillemots use clinometers? Can seabirds recognise deformed rock layers? Are gannets and auks fellow members of the Flint Appreciation Society?

The preparation of this talk has been helped by the staff at RSPB Bempton Cliffs, in particular Sarah Aitken, with whom I collaborated for a number of years and for whom the YGS produced an information leaflet 'The Geology of Bempton Cliffs' for visitors to the reserve. Peter and Sylvia Nettleship of Buckton provided historical data and a 'seabird fact sheet', and almost all of the stunning bird portraits are supplied by an old-school friend, Tony Malt from Malton, who came on a Yorkshire Geology Month boat trip from North Landing in 2016.

The talk will be given at St Francis of Assisi church hall in Kenilworth and broadcast live on Zoom. For full details see https://www.wgcg.co.uk/event/lecture-northern-chalks-and-their-associated-flints/