The Butterfly Monitoring Scheme in Israel (BMS-IL)

Established in April 2009, the Israeli Butterfly Monitoring Scheme (BMS-IL) builds on the long tradition and experience gained through over 30 years of systematic butterfly monitoring by thousands of volunteers across Europe, USA and other regions.
Coordinated by Dr. Racheli Schwartz-Tzachor, Dr. Guy Pe’er and Dubi Benyamini, BMS-IL include three elements: a) systematic observations along fixed transects ("Pollard walks"), b) collation of opportunistic sightings and c) targeted observations on rare species.

(a) Systematic observations along fixed transects serve as the core method in the scheme. Transect lengths range between 300 and 600 m in length, and divide into 50 m sections. Transect usually cover a single habitat type. In each visit, transect-walkers count all butterfly species that can be seen within a range of 5 m range. Special behaviours (egg laying or nectaring), as well as butterfly larvae or eggs, can be registered as well. Transect walks in Europe are performed weekly, but here in Israel, we conduct them once in two weeks from the beginning of October to the end of June - to account for the longer activity period of butterflies in Israel, and the impacts of climate change.

(b) Opportunistic sightings, in which volunteers perform irregular (or singular) observations, are currently being standardised for systematic gathering of data. Relevant information includes the type of observation (e.g. point, polygon or along transect), its exact locality (coordinates), time of the day and, climatic information and a full list of species at a site.

(c) A protocol for data-collection on rare species is currently being developed for four target species: Tomares nesimachus, Apharitis cilissa, Melitaea arduinna and Iolana alfierii. It considers the detectabiltiy of each species during their different life stages, and accordingly takes various methodologies depending on the species (periodic transect count, fixed-time visit, or inspection of host plants in specific sites). Data on the habitat and host-plant phenology are collected as well, in order to relate the status of species to their habitat. Gradually, we intend to develop a protocol for each of the rare species in Israel.