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Posted by Jes

Butterfly Season Report 2016

Butterfly Season Report 2016

After habitat, the most obvious factor that influences our butterflies is weather. No two years are alike when it comes to our ever-changing weather so no two butterfly seasons are identical, each year throwing up shocks and surprises.

Spring (March, April, May) was mainly dry and slightly cool everywhere but May saw some beautiful weather that really brought the spring butterflies and moths out to the joy of butterfly lovers suffering from shortages earlier in spring. Dingy Skipper, Wood White, Cryptic Wood White, Brimstone and the day-flying Narrow-bordered Bee Hawkmoth abounded in their habitats; indeed, the Wood White enjoyed a sizeable second brood in the Burren; in some years, such as 2012, a second brood is small or even absent. The other whites had a mixed year; for example, the Large White showed in increased but still modest numbers but Green-veined White records are well down compared with the 2015 figures. The migrant Clouded Yellow was recorded only once in 2016. The rare Burren speciality, the Pearl-bordered Fritillary was not on the wing until mid-May, the result of cooler conditions earlier in spring. However, when the Pearl-bordered Fritillary did appear, it showed in good numbers, flying throughout the day in the warm sunshine that lasted into early June.

Brimstone, a 2016 success.©J.Harding.

Summer (June, July, August) was mild but often dull with less sunshine than spring and wetter than usual in most areas. The exceptional heat of July 19 came out of nowhere and vanished as quickly. The Small Tortoiseshell, Peacock, Red Admiral (a migrant) and Comma (big decline on 2014-2015) did not perform well in 2016; the large numbers of Peacock and Small Tortoiseshell seen on the cutaway bogland at Lullybeg in 2016 were not reported in any other location in the case of the Peacock and in one other location, on farmland in Bryanstown, Co Meath, in the case of the Small Tortoiseshell. The Painted Lady, a migrant, appeared in higher numbers; 52 were reported to Butterfly Conservation Ireland in 2015 compared with 132 in 2016. Lower numbers were the norm for the three widespread fritillaries, especially for the Silver-washed Fritillary and Marsh Fritillary. There are two reports of high Dark Green Fritillary numbers but lower than the highs of recent years. The Small and Essex Skippers showed in low numbers too.

The Brown family holds some of our most numerous species and their numbers tend to be steady. Meadow Brown, Ringlet performed to their usual high population standard; Speckled Wood performed similarly to previous years. However, the status of the Wall Brown remains parlous; on the brink, if not extinct in Northern Ireland it has declined severely in population size and distribution throughout the rest of the country. It was reported in just seven counties (Dublin, Kildare, Galway, Clare, Donegal, Cork, Wexford) in 2016. The reasons for its shocking reduction are unknown, adding to our fears for its future. There were few Large Heath records but this reflects the low level of recorder visits to wet, intact bog in June. The Small Heath flew from 22 May to 24 August per the records we received with the highest count of 48 being returned from the Cork coast on 1 June. The Hedge Brown/Gatekeeper was late emerging with the first count at the end of July.

In the family Lycaenidae we have three Hairstreaks; of these the rarely encountered Brown Hairstreak showed in higher numbers than in recent years. The few Green Hairstreaks seen reflects the lack of searching while the increase in Purple Hairstreak reports is explained by targeted searches. Of the blues, the Holly Blue showed an increase on 2015. The others, Small and Common Blue, were present in reasonable but unspectacular numbers. The Small Copper was found in low numbers, a frequent feature of this gleaming metallic insect.

A great surprise was Eric Dempsey’s report of a Common Swallowtail in Killoughter, Wicklow. Before Eric could grab his camera, the butterfly disappeared, flying strongly inland. This is a striking European species very rarely seen in Ireland. It is a highly mobile species and given a warming climate this magnificent creature could breed here because its food plants are widely available; it breeds on Fennel (found especially in coastal areas, on rocky ground and in gardens) and Wild Carrot (widespread in semi-natural grassland).

One must consider the circumstances of today’s environment when assessing 2016’s butterfly fortunes. To any butterfly lover whose memory extends to the halcyon era before the late 1970’s, 2016 will probably be a disaster. In my experience, 2016 was average.

I wish it well, but I hope for better.

Finally, we record our gratitude to all who contributed records to our website’s record page; without these reports this account could not be written and we would have no way to monitor our butterflies.

To record our butterflies in 2017, send your records by email to conservation.butterfly@gmail.com telling us:

your name/s,

date of find,

species found,

the life stage/s found,

numbers seen,

location the butterfly/moth was found (e.g. townland name, site name, county),

six figure grid reference, including the letter identifying the 100,000 metre grid square in which the location lies (see http://www.gridreference.ie/ or Discovery Series maps)

weather conditions

and any other interesting comments you wish to provide.

Example: John Smith 14/06/12. 14 Small Blues, 15 Small Heaths, Portrane sand dunes, O254515, County Dublin. Small Blues feeding on Kidney Vetch and Creeping Thistle. Sunny, light breeze, around 18 degrees Celsius.