Wednesday, 11 September 2013

The shear number...

...of young shearwaters which are crawling around Skomer these nights is absolutely mindboggling. Wherever you go you have shearwater chicks flapping and hopping about, trying to find a vantage point on which they can practise their wings. It is magnificent how one can get close to these wild birds and they don't seem to mind nor notice. 
Young Manx Shearwaters everywhere
Shearwater exercising its wings

Unfortunately lots of these young and inexperienced birds which have hatched and are now fledging on Skomer don't even make it as far as the sea. Some fall into muddy puddles and get stuck there, others develop Puffinosis - a mysterious deadly disease, others again venture about in broad daylight and get picked up by the ravens and the gulls. The carnage is incredible. But then again: this is nature. Every day we can watch evolution in action. The survival of the fittest is happening right here on our door step. 

Shearwater carnage...
...wherever you go

These casualties are normal and the species can cope with loosing a high proportion of young birds a year. As long as the feeding conditions out at sea and the breeding conditions on land are favourable we will be able to enjoy the Manx Shearwater in future.

One thing the species really can’t cope with are ground predators. Manx Shearwaters are perfectly adapted to life at sea. They have long stiff wings for chasing over the waves and legs like propellers set far back on their bodies. This design makes them elegant flyers and very good divers but on land they feel alien. They can’t walk properly, they can’t lift off fast, hence they can’t escape from nor defend themselves against ground predators. 

Short legs and long wings don't make it easy to take off

Luckily Skomer is rat free and lots of other islands have become rat free again e.g. Ramsey and Lundy, or are just in the process of eradicating rats (Scilly). As there is a real threat of introducing rats onto Skomer we will be even more vigilant and ask overnight visitors to only bring on sealed bags and rucksacks next year.

For further reading have a look at the Ramsey blog and watch a video of a Cory’s Shearwater getting eaten by a rat. 

Bee, Skomer Warden

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