Lihou

27 and 28 June 2013  

On 27th June Jamie Hooper met Sophie and me as arranged at 2.30 pm to cross to Lihou to monitor and ring the nesting gulls. The weather was near perfect with little wind and largely clear skies. Once across the causeway we worked our way around the island in a clockwise direction. The first beach held at least half a dozen Herring Gull chicks that were the perfect age for ringing. However, following this good start, the next few rocky beaches around to the point leading to Lihoumel were virtually devoid of gulls (although there must have been a few well concealed chicks).

Once around the corner from the Venus Pool, the rocky gulley contained a small gullery with around six pairs of Lesser Black-backed Gulls (all with eggs or tiny chicks), two pairs of Great Black-backed Gulls and half a dozen or so pairs of Herring Gulls. We ringed several chicks here, and then began to work the extensive rocky beach stretching out to the north-west tip of Lihou. If the numbers of gull chicks had so far been rather modest, this changed very quickly. This beach contained Herring Gull chicks wherever we looked. It took some time to work carefully across the beach, ringing almost 40 Herring Gull chicks on this stretch of coastline (all with colour rings). A number of large chicks had accompanied their parents further down the rocky beach, but we left these chicks alone.

The Herring Gull chicks were in the main the perfect size for ringing, with only a very few too small to ring, and a similar number on the verge of flying.  By the time we’d reached the north-west tip of the island time was beginning to run short, and with the densest colony still to ring, we took the decision to finish the day’s work, and return the following afternoon to complete the job.

On this visit we ringed 48 Herring Gull and five Great Black-backed Gull chicks. Four Oystercatcher nests were located (all with eggs), and there were others on the island too.

Returning in cloudier, cooler conditions at 3.30 p.m. the following day we concentrated on the coastline from the north-west tip of Lihou to the causeway. For many years this has tended to be the densest area for nesting gulls, and also the area that has been most productive (as a result of better protection from the elements and the most experienced adults claiming territories here?).

As usual we located several nesting pairs of Great Black-backed Gulls in the north-west corner, and found six chicks to colour ring. Then we entered the main colony of Herring Gulls, and worked our way through ringing another 50 chicks – again the vast majority being the perfect size for ringing.

After we completed this work, we took a walk around Lissroy. The very small Lesser Black-backed Gull colony by the pond did not appear to be present this year, and there were few Herring Gulls around this part of the island. We did, however, locate another five Great Black-backed Gull chicks. There were also a few Shag chicks left in the half a dozen or so nests on Lissroy, but they were on the large size to ring.

Over the two afternoons we had ringed 100 Herring Gull chicks and 11 Great Black-backed Gull chicks. 2013 has clearly been a very successful season for the gulls, with the best productivity for Herring Gulls for many years. In contrast to 2012, there were also more GBBG chicks this year (several areas usually covered were not visited this year due to the lack of time).

This success can be probably be attributed to a combination of factors, including a good supply of natural food, a reduction in rat predation (following the rat depletion initiative run on the island by the Environment Department in the previous two winters), and the erection of ropes to prevent members of the public wandering into the gull nesting areas. Both the latter measures appear to be delivering very worthwhile results and it is very much to be hoped that such measures can be continued in future years.

 

 

PKV

02 July 2013