Important caveat: monitoring started in late May 2026. This means dates shown are "first detected since monitoring began" not genuine first arrivals for the year. Resident species like Chaffinch and Dunnock were present long before we started — their dates simply reflect when the microphone was first switched on. The data becomes genuinely meaningful from January 2027, when we'll have a full year of monitoring. Summer visitors that arrived after 22 May 2026 (like Common Swift) are the only species whose arrival dates are likely to be accurate for 2026. From June 2027 this page will show true year-on-year comparisons.