AIMSTo coincide with the most profitable period for seabird monitoring, optimum weather and day length, TIARG generally visit the Treshnish Isles in the last week of June. The expedition’s base is set up arounda ruined village at the northern end of Lunga. The majority of one week of fieldwork is centred upon Lunga and neighbouring Sgeir a Chaisteil where an annual full seabird census is undertaken.Once the work of the annual census is complete, the 6-8 man TIARG team redirect their effort to thesystematic ringing of specific seabird colonies.Samples of adult and pulli (chicks) of the principal species of breeding seabirds have a lightweight,uniquely numbered, metal ring fitted around one leg. This allows fieldworkers to re-identify themin future years in order to monitor their movement and survival rates. Up to 2,000 birds are ringedannually which includes Puffin, Razorbill, Guillemot, Fulmar, Storm Petrel, Kittiwake, Herring Gull and ShagRinging of Shag includes both pulli (chicks) and the retrapping of breeding adult birds in specific sectionsof the colonies. Since 2006 the conservation value of this aspect of TIARG’s ringing programme hasincreased with its inclusion into the British Trust for Ornithology’s Retrap Adult Survival monitoring programme. To this has been added our long term ringing of Storm Petrel which now is included inanother RAS project.