Range Extension of Bath White in the Himalayas

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The Bath White is a palearctic butterfly and has been reported to be extending its South Asian range westwards in the Himalayas.

  • As per Evans, (Identification of Indian Butterflies, 1932), the distribution of the Bath White in South Asia extends from across Asia eastwards till the North West Himalayas ie Chitral and Murree (basically Pakistan and POK).
  • Wynter-Blyth, (Butterflies of the Indian Region, 1957), records it as occurring in Baluchistan, Peshawar, Chitral to Kashmir and Shipki. Shipki La is a pass in Himachal Pradesh, (I think along Baspa valley) which is probably the general region of the zoogeographic boundary between NW and Central Himalayas.
  • I have caught Bath White in Udhampur district, Jammu and Kashmir in 1981.
  • Haribal, (Butterflies of Sikkim), makes no mention of the butterfly in her book.
  • It has recently been reported by Debashish Joardar from Darjeeling, adjacent to Sikkim, which lies at the boundary of Central Himalayas and North East Himalayas. He has photographed it and very kindly placed it on WikiMedia Cpommons and the same image can be seen in the article.

The question now arises, has the Bath White always been spread across the breadth of the Himalayas but has been unreported or is it steadily spreading eastwards? It appears to be extending Eastwards for the following reasons :-

  • Over well spaced periods (when the books were written, 30 to 40 years apart), it's boundary appears to be moving eastwards.
  • One assumes Evans, Wynter-Blyth and Haribal (and their correspondents) could not overlook a familiar butterfly especially when they have given eastern limits in the books.
  • The UN pattern is characteristic and usually variation in other species does not provide the kind of green blotching as in Bath White UN. (This is strictly not true as other species of Bath White occur in India, but are rarer and their status and distribution needs to be ascertained.)
  • The butterfly is common, prominent and not local over its range. It is not a rare, shy or extremely local species which would have escaped notice.

This new range record has been confirmed by BNHS to Debashish Joardar and he is preparing a field note for publication in the Journal of the Bombay Natural History Society.

Regards, AshLin 12:30, 11 May 2006 (UTC)Reply