|
ore sightings of the totally
black Common Rose follow the report in the March–April 2007 issue of
Nature News, where Simon Chan mentioned spotting two totally black
Common Rose butterflies (Pachliopta aristolochiae asteris).
Subsequent sightings have been reported at various places, including
a
solitary male seen loitering near a track next to Dairy Farm Road
leading to the Adventure Centre.
The
uncharacteristically black butterfly was initially thought to be
either a male Common Batwing (Parides varuna varuna) or Malayan
Batwing (Parides nox erebus). Both species have males with wings
that are jet black with a tinge of blue, and a red abdomen.
The atypical
black Common Rose first came to my attention in March when I saw one
near the Botanic Gardens car park. This lead me to their focus of
attention near the entrance and along the gate to SBG HQ, where its
host plant, Aristolochia tagala, was found.
All black Male Common Rose
discovers regular coloured female
Male pursues
and descends on female
Mating attempt
Male pursues and tries
to mate with female again. |
|
Filming this
‘aberration’ was a nightmare, let alone photographing it! It was
very alert. Every time I thought I was close enough for a shot, it
flew off again. This cat-and-mouse game went on for a few
frustrating and exhausting days. But that made me all the more
determined. Before long, reward came for my perseverance. One
butterfly appeared and flew overhead rather swiftly. But this time,
it sensed a female at the other
end of the fence and slowed down to have a look. Vegetation on my
side of the fence blocked any possibility of filming this
once-in-a-lifetime event. Quickly, I dashed to the other side of the
fence and managed to get three short videos clips, after which I
took several still shots, shown here in sequence.
The pictures show the persistence of an all black
male trying to impress a normal coloured female by showering her
with his pheromones while hovering above her. She seemed to try to
sneak away, only to slow down later to rest, apparently tired from
his insistent harassment. This gave the male the mistaken impression
that she was willing to mate.
I mentioned this phenomenon to Simon and also
offered my theory that perhaps she was just tired carrying all her
eggs and needed to rest once in a while. Simon however proposed an
alternative based on a well-documented study. That study indicates
that female Pieridae butterflies, when already impregnated or
uninterested in a suitor would settle with wings opened flat and
abdomen raised skywards.
As humans, we would think of this as a sign of
her consent and not of her disinterest. Once mated and freed from
the clutches of her mate, her life’s work starts immediately. In her
lifetime, if she is lucky not to be eaten, she will lay hundreds of
eggs on the host plant. However, most of its young will fall prey to
parasitic flies and wasps, birds, geckoes and even fungi.
I have now seen seven Common Rose butterflies
with at least two totally black males. Hopefully, this will soon
mean there will be many uncommon all black Common Rose butterflies
flying around. |
