Last week the Tag-n-Track team visited the mixed gull colony at Loch Thom to trap some of the adult lesser black-backed gulls to fit them with the GSM tags. The island plays host to nesting greater black-backed gull, herring gull, lesser black-backed gull, common gull as well as canada geese and oystercatcher.
We had been keeping an eye on the island since March to gauge numbers and spot potential nest locations for the lessers. A team of us met on the shoreline where we had planned for two of us to go over by canoe to set the traps whilst the remainder observed the gulls behaviour and prepared to start recording the birds biometrics.
However, we realised that the canoe wasn’t needed as lack of rainfall and work that was being carried out on the reservoir walls had led to water levels being low enough that we could walk onto the island. We also noted that there was a lot less birds present since the previous visit at the start of May. The reason for this soon became apparent when we went to investigate.
Our previous visit onto the island had found a rough count of 60 mixed gull nests (see photo), 20 canada goose nests and one oystercatcher nest. There was no evidence of any eggs apart from 3-4 eggs shells that may have been predated. Each nest had systematically been emptied and the lack of predation evidence on an island which potentially held 400 eggs has led us to the conclusion that humans are to blame. We have reported the matter to Greenock Police, where some of our tagged birds nest and they will enquiries to see if anyone is selling gull eggs.
This event has been really disheartening for the TnT team particularly because of the impact on the gulls nesting season at Loch Thom. If you have any information on what may have happened please contact us at the Park on 01505 614791.