It’s a few weeks ago now (8th April) since the first returning swallow was sighted in Sheldon this year. The earliest national record from this year’s national survey conducted by the Woodland Trust in conjunction with the BBCs Big Spring Watch was 20th March. As many of us will be aware the signs of spring are often much earlier than they once were and the study of this phenomenon of change is called Phenology. To find out more about this go to http://www.naturescalendar.org.uk/.
The arrival time of swallows is linked to temperature and weather conditions. This can mean a relatively small increase over the average temperature in spring can result in swallows arriving 2-3 days earlier see http://www.ecn.ac.uk/iccuk/indicators/29.htm. Localised events such as storms at sea or wind direction can also influence arrival time.
The overall trend is clearly linked to rising temperatures and it effects much of our wildlife, for example, frogs spawning, plants flowering, trees coming into leaf, insects becoming active, birds nesting and bats emerging from their winter hibernation sites.
In Sheldon, Bronwen Slack has been keeping records of her observations of first swallow arrivals in the village for many years. The graph below shows her* first recorded arrival dates between the years 2001 and 2015 and the average April temperatures for central England supplied by the Met Office. The relationship between temperature and arrival time can be clearly seen with one or two anomalies and the overall trend seen in the line through the arrival dates is becoming earlier. * Some records supplied by Julian Gregory and Georgina Slack.
An interactive map of 2015 UK swallow arrivals can be seen at the link below.
I have seen house martins returning to their nests at Deepdale Business Park in Bakewell this week and have seen them at Devonshire View Cottage in Sheldon for the first time this year today.
Other than this a walk over to Magpie mine on Sunday 3rd May found many cowslips out in full bloom and a few mountain pansies were also on display. Skylarks were singing between the rain showers. We also found a nice shiny Dor Beetle!