Like glimpsing that first spring Swallow, the first butterfly sighting of the year always quickens the pulse.
Although it is possible to see butterflies flying in any month, their abundance and diversity is at its greatest towards the warm months from late-Spring to early-Autumn. It’s no coincidence that butterfly monitoring transects run from 1 April until 30 September each year. For the rest of the year, sightings are relatively scarce and, as a result, disproportionately exciting and joyful experiences.
The first Brimstone of the spring undoubtedly produces a bigger lift to the soul than the first one of the summer generation, and while I never tire of seeing Red Admirals massing on late summer blossom, the sight of one on a crisp, sunny mid-winter’s day is definitely something special. And I’m sure I’m not the only butterfly watcher in Britain who keeps a note of the date of that all-important first butterfly sighting each year. Last year, during the long cold spring, I didn’t see my first butterfly (a Small Tortoiseshell) until 6th April, the latest date in 12 years of keeping note. Only once previously have I failed to see a single butterfly until April, in 2006, which also, like 2013, eventually gave way to a glorious summer.
But, some butterfly recorders fared much better than me at the beginning of last year. During a very mild spell, an amazing six different species of butterflies were recorded on New Year’s Day 2013 in southern parts of the UK. What’s more, in most cases these weren’t isolated incidents; Brimstones and Small Tortoiseshells were reported from two counties each, Peacocks and Painted Ladies from five counties each and Red Admirals were seen in at least seven different southern counties. The most unusual sighting of New Year’s Day 2013, however, was of a Speckled Wood in Cornwall.
It is not unusual nowadays for a butterfly to be seen somewhere in the UK on New Year’s Day. It has happened in most years over the past decade or so, with Red Admiral the most commonly reported species, but typically only one or two species are reported on the first day of the year. So the six species in 2013 is certainly highly unusual.
Even if the weather on New Year’s Day itself is too poor for any butterflies to venture out, it is unlikely that we’ll be waiting long for the first UK sighting of the year. Over the past decade, the average first sighting date for Red Admiral has been 4th January, Peacock 5th January, Small Tortoiseshell 9th January and Brimstone 14th January. The Comma is usually the last of the butterflies that overwinter as adults to emerge, with an average date of 31st January (although it can be much earlier e.g. 8th January 2013).
The Speckled Wood spends the winter as either a caterpillar or a pupa and, therefore, is much less likely to be fully-developed and on the wing as a butterfly so early in the year. Nevertheless, aside from 2013, this species was also seen in January in 2012, 2009, 2008 and 2007. Although each of these sightings was of an active butterfly seen out of doors, it is possible that the overwinter development of these individuals had been artificially quickened. For example, sometimes caterpillars pupate in greenhouses, conservatories, compost bins or other locations that are warmer than the outside world and the higher temperatures experienced by such pupae might lead to early emergence of adults.
There is a First Sightings page on the Butterfly Conservation website – please report sightings of any free-flying butterflies not yet seen during 2014. Of course, even if a species has already been spotted, your sightings will be welcomed by your local Branch (to form part of our national recording scheme) and you can share the news via Twitter or Facebook.
Happy New Year and happy butterfly spotting in 2014!
Richard Fox, Surveys Manager.
Follow me on Twitter: @RichardFoxBC