Last week we celebrated World Oceans Day. The world's oceans are vital, providing food, regulating our climate, and providing a home for countless different types of wildlife. But they are under threat from pollution - not least the rapidly rising tide of plastic that's finding its way there - overfishing, and climate change. 

The RSPB works very closely with our Birdlife International partners to protect the world's oceans and the wildlife that lives there. You can read all about the amazing work that we're doing to protect albatrosses in the southern oceans here. The UK Overseas Territories are home to many of the most important seabird colonies in the world, including penguins and albatrosses, as well as a host of other unique species, and the RSPB is busy on many of these territories too, as you can read here.

Black-browed albatross and chick by Ruedi Abbhehl (rspb-images.com) - one of the seabird species that breeds on UK Overseas Territories

Closer to home, the UK is incredibly important for seabirds, too, with some of the biggest colonies in the North Atlantic on our shores, including such amazing places as RSPB Bempton Cliffs, RSPB Ramsey Island, and RSPB Fowlsheugh.

When you think of seabird colonies, I guess most people will immediately think of the bustling sea cliffs, such as those on the reserves mentioned above, where guillemots and razorbills crowd onto any available ledge, puffins and (on some western and northern islands) Manx shearwaters burrow into the grassy higher slopes, and gannets and fulmars cruise on the updrafts, barely flapping their long straight wings. But among them all, one bird is often overlooked: the kittiwake.

Kittiwakes are the commonest gulls in the world, and indeed here in the UK, with many colonies exceeding 10000 breeding pairs. They are also our only true "seagull", spending their entire lives at sea. They almost always nest overlooking the sea, on high, inaccessible sea cliffs of highrise buildings along the shore. It is very rare to see a kittiwake inland, although a well-known colony in Gateshead nests on the Baltic Mill, overlooking the River Tyne about 15 miles inland.

Regular readers will be aware that Minsmere has become a good place to spot kittiwakes in the spring, but for many of our visitors it's a surprise to see flocks of these elegant gulls on the Scrape. That surprise is perfectly understandable. Why would a bird that is at home on the steepest cliffs even be seen in a county with no such cliffs, never mind on the Scrape?

Kittiwake by Oscar Dewhurst, showing the characteristic "dipped in ink" wingtips

In fact, there are two breeding colonies in Suffolk, both of which use manmade structures as alternatives to sea cliffs. One of these colonies breeds in Lowestoft, about 20 miles north of Minsmere, where they nest on various buildings. They first colonised one of the piers in the 1950s, before moving to a specially constructed wall in the entrance to the docks. More recently they've moved onto ledges on churches and even shops along the main shopping precinct, where, unusually, they are not nesting directly overlooking the sea!

As the colony in Lowestoft expanded, some dispersed along the coast in search of alternative nesting ledges, but these are few and afar between in low-lying East Anglia. They did, however, find another manmade structure nearby, and this one was even more suitable as the nests are directly above the sea. This second colony is on the outfall rigs that were constructed for the Sizewell A power station in the 1960s.

Although many of the UK's colonies are in decline as a result of recent breeding failures linked to climate change and falling fish stocks, here in Suffolk their breeding success appears to be good and the populations are continuing to grow.

With the proximity of the Sizewell colony to Minsmere, it's perhaps not a  surprise that some of these kittiwakes have been visiting the Scrape in recent years to gather nesting material and bathe. These flocks even reach as many as 100 birds during April and May, and many visitors have enjoyed close views of them resting on the crossbars in front of East Hide or the shingle islands on South Scrape.

Kittiwakes by Steve Everett, showing the black legs that give them their alternative name of black-legged kittiwake

It still seems strange to me to hear the distinctive "kitt-ee-wake" call among the raucous black-headed gulls and cat-like mewing of Mediterranean gulls, but clearly these beautiful gulls have found the Scrape to their liking.

So much so that a few pairs have decided to nest on South Scrape this year. On the ground! This was not something that we had expected, despite the attractiveness of the Scrape to many other species of gulls and terns, but there are at least three kittiwake nests sitting proudly on one of the islands on South Scrape.

Some of the kittiwakes resting on South Scrape this time last year

While ground-nesting is not unknown for the normally high-rise kittiwake, it is certainly extremely unusual behaviour. I've been able to find evidence of one long-established colony in Scandinavia, and one or two previous attempts at ground nesting in the UK, but that seems to be about it. We now hoping that the arrival of cool weather and heavy rain doesn't affect their chances of success.

The arrival of a new breeding species at Minsmere may be the biggest headline of the breeding season so far, but it's certainly not the only news. Tern colonies often play second fiddle to sea cliffs when we think of seabird colonies, but they are invariably more accessible. Little terns, in particular, often choose to nest on shingle beaches - the same beaches that are favoured by humans. As a result, many colonies are easily disturbed. These same beach nests are also at risk during summer storms, so it's great to be able to report, as mentioned in last week's blog, that we have little terns breeding for the first time since 2009, also on islands on South Scrape. We also have the biggest numbers of common terns since 2011, Sandwich terns since 2009 and Mediterranean gulls ever. Hopefully they will also survive the inclement weather.

Mediterranean gulls

Other sightings on the Scrape this week have included the family of escaped bar-headed geese (which still have one chick), the first avocet chicks of the year, up to three spoonbills, and a few passage waders, which have included dunlins, sanderling and ringed plovers. We expect the first southbound spotted redshanks to arrive this week too.

In the reedbed, there are regular sightings of otters, bitterns, marsh harriers, hobbies and bearded tits, plus singing reed, sedge and Cetti's warblers and reed buntings. The two Savi's warblers are still singing at Island Mere too, and a grasshopper warbler was heard for the first time in several weeks near South Hide this morning.

Reed warbler by Jon Evans

Garden warblers are singing around the Work Centre and Whin Hill, blackcaps and long-tailed tits have been very visible around the pond, and bullfinches are being seen more frequently than usual for early summer in the North Bushes. There are also green woodpeckers in North Bushes and at Whin Hill, regular great spotted woodpeckers on the feeders, and cuckoos singing around the reserve. Not forgetting, of course, the many insects that often steal the show for visitors and volunteers - more of that later in the week.