Procedures for Storm Petrel ringing on Fair Isle and the possible capture of Swinhoe’s Petrel (2015)

Procedures for Storm Petrel ringing on Fair Isle and the possible capture of Swinhoe’s Petrel

Storm Petrel ringing

Since the mid 1980s, Storm-petrels (mainly European Storm-petrels, although a few Leach’s Storm-petrels are caught every year too) are caught for ringing on the flat, grassy area below the bird observatory on Fair Isle.  The birds are trapped during the short, late-summer nights using a mist net and a recording of storm-petrel vocalisations.  The vast majority of the birds caught are pre-breeding wanderers, but the data nonetheless provide a great deal of useful information on movements, life-histories and (when corrected for effort) a crude index of abundance.  The main trapping season is from early July to late August, although if the weather is favourable, some effort is occasionally made a week or two either side of that window.  Birds trapped are processed by the Observatory ringers in the FIBOT garages, which are safely accessible by a metalled track from the Observatory.  In turn, this allows a safe way for members of the public, and particularly those keen to have their first experience of seabird ringing, to see the operation.  There can be few better ways to ring your first bird, or see storm-petrels in the hand for the first time.

Procedures if the returning Swinhoe’s Petrel is caught
Catching will be carried out as normal, playing lures of the full mix of species (potentially including Swinhoe’s), on nights where the weather is appropriate, until (if) the returning bird is caught.  If another individual is caught, the procedures will not change unless it is caught a second time. 

If the returning bird is caught, or another Swinhoe’s is caught more than once, then the following procedures will apply: 

·         The first time Swinhoe’s is caught trapping will continue until the normal end of the session (without Swinhoe’s tape) to see whether the bird is likely to keep returning to the trapping area.  If it is clearly still present in the area, trapping will stop for the night and from then on, trapping will stop for the night if it is caught.
·         Swinhoe’s lure will not be played
·         Petrel catching will take place on a maximum three nights a week (ie Monday to Sunday).
·         The nights when there will be catching will not be publicised in advance and the decision to ring will be made on a daily basis.
·         There will be no more than two consecutive nights trapping.
·         The bird’s behaviour will be monitored as the season progresses.  If it appears to becoming fixated with the trapping area (i.e. calling on none-trapping nights, being one of the first birds to the net), the situation will be reviewed and will likely end trapping for the year
·         Ringing process: the bird would be taken to the shed for processing, held for a maximum of five minutes (except on the first occasion, when some extra time may be allowed for islanders etc to get to the Observatory, after that, anyone wanting to see it will have to be at the sessions).  Only weight will be taken after any initial catch, when full biometrics may be recorded.

In the event of the bird being caught, the news will go out through the usual channels, Facebook, Twitter, Blog, Birdguides etc.

Fair Isle Bird Observatory Trust

BTO

3rd February 2015