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Read by Charley and Dave
Gannets, puffins and other seabird species will mate for life. For puffins this is an 18 year commitment on average and for gannets it is 35 years. But before this each individual has to first find a mate.
For puffins we have already seen that they grow brightly coloured beaks every year and display them in a ritual known as billing to attract a mate. Males may also fight over the attentions of a mate by locking their bills together and stamping their feet, an event that quite often draws a lot of puffin spectators.
Gannets attract a mate through a process known as ‘sky-pointing’. The birds will raise their heads to the air and click their beaks against each others (not too different to billing in puffins). Not just a behaviour to attract a mate, again like billing for puffins, gannets will continue to sky-point throughout their mating life together to re-affirm their bonds.
Finding a mate is one step, but the birds also need to find somewhere to create a nest; gannets and puffins will both, like many other seabirds, first try to nest in the same location where they were born. Gannets will start their breeding life by making a nest on available rock ledges on the edge of the colony. But as they get older and more experienced in breeding they take over nests closer to the centre of the colony where it is safer from predators.
Puffins will start to find a site to breed before they start breeding. When they are 3-4 years old they come to breeding colonies late in the season to look for burrows to use the following year. But they often find burrows after the pair that is already in residence has left for the season after raising a chick. So when the young puffins come back the following year to breed for the first time they go to the burrow they chose only to find other puffins already in there. The puffins will then fight over the territory. If an existing burrow cannot be taken then, as we have seen, puffins will dig a new burrow. Gannets will also fight over nesting territory.
If colonies are full, no more room for burrows or rock space for nests, then puffins and gannets will move to new locations to find more room. This is how populations spread and new colonies become established.
On Tuesday I told you all about the gull population count. Today I will tell you about the other part of that Burhou trip - gull ringing. We attach rings on to many birds so that they can be identified again in the future and we get some ideas of how long lived birds are and where they go to feed and migrate.
Each gull actually gets two rings. The first one is metal and can be recovered from any birds that are found dead to tell us how old it was.
The second ring is a larger colour ring. These can be seen on gulls by anyone with binoculars or a scope. Reporting these sightings of colour rings on live birds allows us to see where they feed and forage.
We also measure the head and bill length of each gull to determine what sex it is, females will be a bit smaller than males for our gull species'.
After just a couple of minutes in the hand to ring the gulls they are then safely released back in to the colony.
Unfortunately you cannot make out the ring number, but even our live camera picks up the ring on a gulls leg. This is the type of sight you have to look out for when ring recording.