In this guest blog, Laura Bambini, the RSPB’s seabird recovery officer recounts a recent close encounter with a Manx shearwater colony on Lundy Island in north Devon.
Seabirds are wonderfully elegant and enigmatic – we still know so little about their lives which are mostly spent out in the open ocean. They are able to brave the wildest storms out at sea to return to their breeding colonies on land every year, and we are just beginning to understand the struggles they face to find and bring back food for their young. Over the last few years, we have seen several sad stories of dramatic seabird declines from around the world. There are fears that climate change will decimate the UK’s kittiwake, puffin and tern populations, and that our best seabird sites will fall silent forever.
The UK has special importance for seabirds in Europe, being home to around a third of the EU’s breeding seabird populations. But for two species of seabird, most of the global breeding population is in the UK: the great skua, and the Manx shearwater. The great skua, or Bonxie as it is known in its haunts in the islands of Scotland, is a robust and seemingly fearless bird. Around 60% of the global breeding population is found in Scotland. It is easy to come into close contact with these magnificent birds in their moorland breeding grounds, for the Bonxie will defend its territory against all intruders, including the intrepid hillwalker.
Great skua. Photo credit Andy Hay
Not so with the dainty Manx shearwater. The UK holds a staggering 80% of the global breeding Manx shearwaters, or Manxies, but it is a rare privilege to come into close contact with these beautiful birds. The Manxie is a medium-sized seabird in the Procellariidae, or tubenose family. This family includes the true ocean wanderers: the fulmars, prions, petrels and shearwaters. Clumsy on land, these birds are unparalleled when in their element in the open ocean, and effortlessly travel for hundreds of miles on their long foraging trips in search for small fish and cephalopods. The Manx shearwaters return to their breeding colonies in March to reunite with their mate and to secure a burrow – usually the same one every year. The male and the female take turns to incubate a single egg, and to feed the chick. The changeover happens at night, under the cover of darkness. This is to avoid predators, and during the day a Manx shearwater colony is silently biding its time underground. But when the sun goes down, an eerie sound emerges from the burrows. The birds on parenting duty are calling their partners, and soon dark shapes start gliding past and calling back. The Manxie is elegant when flying, but it is hard to keep up the appearances when it comes to landing. Most of them promptly crash land near their burrow and shuffle and belly-glide to the entrance, propelled by legs that are perfectly adapted to swimming, but so far back on the body as to be completely unsuited to walking.
Manx shearwater. Photo credit Chris Gomersall
I was lucky enough to visit one such Manxie colony on the island of Lundy this month, and felt moved when quietly watching and listening to this spectacle unfolding around us. Listening to the birds calling from their burrows, no doubt hungry after a long spell incubating and patiently waiting to get out to sea again to feed, I found myself contemplating the intricate lives these enigmatic seabirds lead. I felt in awe of their endurance and determination in tackling the challenges of their long winter migration, and the effort required to bring up a single chick. The parents feed the chick until it is much heavier than the adult birds themselves, at around 60-70 days old. The chick is then left to fend for itself, and spends 8-9 days alone before fledging. The young birds from the small number of colonies around the UK join the adults on a long migration to overwinter off the coasts of Brazil and Argentina, and only return to breed when they are around 5-6 years old. The Manxie and most of its tubenosed relatives can only breed on islands that are free of mammalian predators, especially rats and cats.
The purpose of my stay on Lundy was to participate in Manx shearwater surveys that are carried out every four years to monitor the breeding colony there. The island was declared rat-free in 2006 following a successful eradication operation, a partnership between Natural England, RSPB, National Trust and Landmark Trust, and encouragingly the Manx shearwater numbers have been on the rise ever since. A team from the RSPB and Natural England spent a week carrying out playback surveys on the island, which entails playing a recording of the birds’ call at the entrance of each burrow, to which the occupant will respond, enabling researchers to estimate the number of breeding pairs present. This is an established technique for monitoring burrow-nesting shearwaters and petrels. The data from this year’s survey is currently being analysed, but my conclusion is clear: we must do right by these magnificent birds and protect our special seabird islands from the threats they face. Eradicating predators, once established, can be challenging and very costly. However, by taking simple steps we can keep our islands predator-free in the first place. For example by packing on the day of the trip, checking all bags and vessels before leaving for an island, and taking all rubbish and food waste with you when leaving the island, we can all do our bit to ensure that future generations of the UK’s Manxies and other seabirds have a safe breeding site to return to. In today’s complex world of conservation threats facing our seabirds, maintaining predator-free islands is an effective way to help them tackle the challenges in the life of an ocean wanderer.