Wednesday 3 April 2013

Gannets

This is the largest seabird in the North Atlantic, with an increasing population in Shetland with colonies at Noss, Hermaness on Unst as well as on Fair Isle. Overall  the UK has around 250,000 gannets 58% of the world's population.

Shetland supports around 10% of the UK population. Normally birds winter of the coast of Africa returning to the cliffs around February with eggs laid in April. Breeding begins around the age of 5 or 6 years and then they stay together for years. When the arrive back on the steep cliffs pair bonding takes place and this involves shaking their heads from side to side, while sometimes leaning back , the head extended upwards and the bill  pointing downwards.



The nest is large and can be made of seaweed, feathers, vegetation and sometimes with fishing nets. Not all of this is collected outside the colony as there is continual stealing of material from nests nearby.


New EU polices at the beginning of March agreed to phase out the controversial practice of dumping unwanted fish back into the sea. Dr Votier of Plymouth University believes that the new ban on fish disgards is essential to cut waste and improve the fish stocks.

This could have an effect on Gannets as some individuals rely heavily on fish disgards others focus more on Mackerel and Herring. Birds have been tracked travelling to South West Norway for food as well as targeting fishing vessels for disgards.Cameras have been attached to gannets revealing 42% of birds regularly targeted fishing vessels as well as searching for natural prey. While 81% of these were male Gannets but only 30% were females.

Gannets are the only consistently successful breeding seabird in the North Atlantic so it will be interesting to see how they will adapt to these new policies. Its not only Gannets that are attracted to fish disgards, a study in the late 1980's early 1990's revealed that the number of seabirds potentially supported by fish waste was around 5.9 million. That's a vast number !!!




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