Early Season Highs. March 2019.
Written by Jos   

Large Tortoiseshell

 

 

Butterfly season opens - a Small Tortoiseshell on 12 March, my earliest ever butterfly flying in Lithuania. Beyond that, still a good couple of weeks earlier than usual, warm sun from the 23rd onwards added more early season surprises, several splendid Yellow-legged Tortoiseshells, an impressive eight Large Tortoiseshells and 23 Camberwell Beauties!

 

 

 

 

 

1-12 March. Early Start.

Beginning of March, temperatures clambering above zero, snow melting, a very early spring for 2019. And with it, already the first Cranes had appeared at Labanoras on 21 February, my earliest ever. As the weather improved in early March, so more migrants arrived, Skylarks on the first day of the month, Lapwings and Starlings a few days later, numerous Bean Geese and numbers of Whooper Swans flying over in the days after.

 

Small Tortoiseshell

 

 

On the 12 March, temperatures positively soared to an almost tropical 12 C ...and, yay, so opened the butterfly season - an exceptionally early date for this country, one Small Tortoiseshell soaking up the early spring sunshine in meadows south of the capital. Also first spring flowers, first toad of the year - the joys of spring.

 

 

 

 

23-24 March. Big Beasties - Large and Yellow-legged Tortoiseshells.

After the early Small Tortoiseshell, predictably two weeks thereafter of temperatures barely exceeding 5 C and not a single butterfly seen. Still however plenty of incoming birds, White-tailed Eagles, Great White Egrets and Woodlarks among the rewards at Labanoras.

And so to the second half of the month, frequently in Lithuania still bedecked in snow or characterized by rain ...thus, understandably, it is rare indeed to see many butterflies in such! Not so this year however - with temperatures rising again to a pleasant 10-12 C on both the 23rd and 24th, I did have some expectations, but certainly not of the unexpected bonanza that was awaiting!

 

Day One, Labanoras.

A backdrop of Skylarks in full song, Cranes yodelling, White-fronted Geese passing north. Mid-morning, not a trace of wind, the sun nicely warming the woodland edge ...and then that bright dash of vivid yellow, my first Brimstone of the year, all too soon several more splashes of yellow, a whole bunch of very nice Brimstones, a true feeling of spring.

 

 Yellow-legged Tortoiseshell

 

Nice, but perhaps expected. Less so for the next one - a cracking Yellow-legged Tortoiseshell taking in the sun. Reasonably regular at Labanoras , this nevertheless a grand way to get the season going in style.

So, the day's tally - no less than 35 Brimstones on the wing, one Small Tortoiseshell and, of course, the Yellow-legged Tortoiseshell.

 

 

 

Day Two, Mixed Sites South of Vilnius.

A degree or two cooler than the day before, a slightly chilly breeze. Thought the day was not going to be as good - and in one way I was correct, only two Brimstones all day. But today it was 'day of the big beasties' - something I totally did not expect in March, not only my first Comma of the year and a total of eight Small Tortoiseshells, but also both Large and Yellow-legged Tortoiseshells!  Offering perfect opportunity to compare these similar species, found first a Yellow-legged Tortoiseshell, then another, then a loose colony of eight Large Tortoiseshells! Given the general scarcity of both of these butterflies, a very impressive showing I thought.

 

MASTERCLASS IN IDENTIFICATION OF THE LARGER TORTOISESHELLS:

A. Separating from Small Tortoiseshell

Apart from the obvious size difference, both of the larger tortoiseshells have orangey basal areas to the upper rear wings, whereas Small Tortoiseshell is dark in this area. This feature is easy to see even in flight. Additionally, Small Tortoiseshell has three dark spots on the upper surface of the front wings, while both Large and Yellow-legged Tortoiseshells have four spots in this region.

 

Small Tortoiseshell
Yellow-legged Tortoiseshell

Typical flight patterns are also different - Small Tortoiseshells tends to fly low and fluttery, rarely climbing to heights. By contrast, both Large and Yellow-legged Tortoiseshells are fairly powerful fliers, often sailing considerable distances, often rising to tree top level.

 

B. Separting Large and Yellow-legged Tortoiseshells

Superficially similar, though a number of distinctive features. Though not always easy to see, leg colour is the obvious feature separating them - Large Tortoiseshell has all dark legs, while Yellow-legged Tortoiseshell has pale legs, especially tibia and tarsal segments (though can appear dark in the field due to shading).

 

Large Tortoiseshell

 Yellow-legged Tortoiseshell

 

On the upperwings, the rear margins of the hind wings are also distinctive. On Large Tortoiseshell, the blackish sub-marginal band tends to be narrower and ends fairly neatly, frequently a very narrow band of pale orange separating the black from the general orange of the rest of the wing. On Yellow-legged Tortoiseshell, the blackish band is broader and tends to blur into the orange, a not very neat look.

 

Large Tortoiseshell

Yellow-legged Tortoiseshell

 

Additionally, the white blotch near the apex of the front wing tends to be whiter in Yellow-legged Tortoiseshell, while off-white in Large Tortoiseshell.

 

 

25-28 March. Pause.

Predictably, the weather then changed, a fresh layer of snow descending, temperatures dipping to minus 4 C on 26th. A pause to early butterfly action!

 

30 March. Rise of the Beauties.

Stunning day - 17 C, the warmest ever March day that I remember on Lithuania! And to celebrate, my first trip of the year to the far south of the country. Stacks of butterflies flying - perhaps over 250 individual butterflies during the day, this also a March record for me (in comparison, for the total months of March 2017 and 2018, I saw a total of just two butterflies in the first of these years and eight in the second).

From early morning onwards, in open pines, along sunny banks, Brimstones fluttering in abundance, a sheer delight. In among them, my first of the year, as many as 40 Peacocks, a few Commas and a singles of Small Tortoiseshell and Yellow-legged Tortoiseshell. For sheer wow factor, however, butterfly of the day was Camberwell Beauty, a species that generally flies from mid-April.

 

 

Camberwell Beauty

 

 

Always a stunning species, but here on this day they truly dazzled, manyloads of them flying along sunny forest tracks, in one area as many as four together. By day's end, I had seen a grand total of 23 Camberwell Beauties, one of my highest ever day tallies for the species!

 

 

 

 

Camberwell Beauty

 

 

31 March. Tumbling Temps, Gusting Winds.

Topsy turvy spring continues, a mere 10 C and exceptionally strong winds - predictably not a single butterfly on the wing! Still, still growing evidence of spring - many hundreds of Fieldfares and Redwings moving north at Labanoras, plus dozens of White Storks drifting about, many already atop their nests. Also first Green Sandpipers back on territory, notable rise in Chaffinches et al.

 

Last Updated ( Thursday, 11 April 2019 )