Thursday 13 March 2014

WHERE ARE ALL THE BUTTERFLIES DURING WINTER?


Peacock by Fran O'Connell
Butterflies cannot survive our winters as flying adults due to the cold and lack of food. To survive the adverse winter conditions, most but not all, species of butterfly hibernate. Thus most species of butterfly are all around us during the colder months of autumn, winter and spring. However, dependent on the species, they adopt a variety of different strategies to survive until suitable conditions return.



Painted Lady by Daniel Wheldon
MIGRATION
Amazingly, just like swallows and warblers, some species of butterfly migrate south to Africa to avoid our
Small Tortoise Shell by Bernie Sheridan
colder months. Red admirals, painted ladies and in some years clouded yellows migrate in summer from Southern Europe and Africa to Ireland. It was once considered that most, if not all, died with the onset of colder weather. However, radar studies have now proven that these species are capable of a reverse migration to sunnier climes in Africa. These epic journeys involve thousands of kilometres which is truly phenomenal for such a tiny creature. The numbers involved in these movements can run to millions of individuals.

Comma by John Joe & Liam Cahill
ADULTS
A number of species including small tortoiseshells, peacocks and commas hibernate as adults. These species build up sufficient fat reserves during summer/autumn to enable them to survive the long colder months. They seek out suitable niches in trees, buildings, crevices etc. and hibernate. Most people will be familiar with small tortoiseshells hibernating on the walls of their homes. If you come across a hibernating butterfly it is best to leave them well alone to sleep.


 CHRYALIS/PUPAE
Wall Brown by BernieSheridan
This is the stage between the caterpillar and the flying adult butterfly. The chrysalis spends the winter at the base of plants or underground thus avoiding the worst of the winter weather. When conditions improve in spring/summer the chrysalis metamorphoses into the flying adult butterfly. Large whites, small whites, orange-tips and holly blues among others adopt this policy.

Common Blue by Fran O'Connell
CATERPILLAR/LARVA
Many species spend the winter as caterpillars. The advantage of this strategy is that, being mobile, caterpillars can hunker down in deep cover in adverse conditions and emerge to feed at opportune times. A caterpillar can also move to avoid flooding, predators and other dangers. Common blues, small coppers, fritillaries, wall browns, gatekeepers, meadow browns, small heaths and ringlets use this strategy.



EGGS
Small Copper by Bernie Sheridan
The purple hairstreak over-winters as an egg. The eggs are laid in July/August. The Caterpillar quickly develops within the egg, immediately hibernates and does not hatch until the following April. The caterpillar then feeds on the emerging buds of oak trees – its only food source. Oak leaves contain tannins which are poisonous so early feeding on the buds may avoid this hazard.





Silver-washed Fritillary by Fran O'Connell
THIS YEARS BUTTERFLIES
The spring/early summer being wet and relatively cold was not conducive to butterflies. Species such as orange-tips, green-veined whites and green hairstreaks seemed to be flying in reduced numbers. As the summer progressed and the weather grew warmer conditions became optimal for adult butterflies. Large numbers of whites, red admirals, peacocks, silver-washed fritillaries and common blues were on the wing. Wall browns were in good numbers in suitable habitats and the beautiful small copper very much in evidence. 

After a number of poor summers this augurs well for the future wellbeing of butterfly populations.

Commas consolidated their expansion into Waterford with multiple additional sightings in the Mount Congreve area.

RECENT WILDLIFE SIGHTINGS
The spoonbill has returned to Dungarvan for yet another winter as have a number of long-tailed ducks. A new surf scoter is presently overwintering in Dungarvan harbour and a number of yellow-legged gulls are on the Colligan River at Ballyneety.

Fin and minke whales, common dolphins and porpoises, harbour/common seals, grey seals and otters are presently being encountered along the Waterford coast.

Watch out for returning thrushes such as redwing and fieldfare over the next several weeks.


Check out www.waterfordbirds.com for local wildlife updates and submission of records. If you have

Any questions or comments please email them to japwatntr@gmail.com.


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