78,000 gannets make Grassholm their home.
As you approach the island, you begin to understand why it's white. It's home to 39,000 pairs of breeding gannets, the only gannet colony in Wales and third largest in the UK.
The island comes alive in early spring, with gannets returning to the island from late February onwards. The air is filled with males returning with nesting materials keen to establish territory ready to attract a female.
A single egg is laid in April and chicks begin to hatch in early June. The chicks are then fed by both parents for 90 days until they are fully grown and ready to leave the island in late August and throughout September. As one of only 23 gannet colonies in the UK and Ireland, Grassholm is of both national and international importance. It is an outstanding seabird spectacle, unrivalled anywhere in Wales for this species. Grassholm is a RSPB reserve with a strict 'no landing' policy, but several boat operators offer trips out to island to experience the sights and smells first hand
Boat trips are available from Martins Haven with Dale Sailing, or with Thousand Islands and Voyages of Discovery from St Justinians.
It must be something to do with our mild climate plus those Atlantic storms that sweep in now and then that makes Pembrokeshire such a ‘twitchers’ delight.
As you travel around the sweeping coastline of St Brides Bay you’ll spot the white flank of Grassholm Island. Find out why the island is white and how to get yourself there.
Planning where to eat if you're a coeliac can be challenging - here are our top locations from our followers on social media.
Tourism Department, Pembrokeshire County Council, County Hall, Haverfordwest, Pembrokeshire, SA61 1TP.