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Exploitation of natural resources has serious damaged the bio-diversity of forest land in Taiwan. To know whether the environment is damaged or destroyed and to what extent by conducting animal and plant resources surveys, may help understand the biological content of the environment. Along with the objective method of comparative analysis, should be able to provide timely warnings and to achieve adequate environmental protection. Many butterfly surveys have been conducted in Taiwan, but mostly localized and on seasonal variations. Very few studies have been performed on diurnal activities. The only detail transactional study was done at the Sitou Forest. Another study was done at the Taipei Zoo on the diurnal activities of rotten fruit butterflies on food preference. This study focuses on a systematic survey of butterfly resources in different environments at Taipei basin, namely open land, forest margin, forest and the crest line of a natural forest park. Impact of the habitat environment characteristics such as butterfly composition, changes in butterfly behavior and distribution of butterfly types, on the diurnal activities is assessed to establish the spatial and temporal changes in butterfly activities in different habitat environment. Between September 2008 and August 2009, 21 effective surveys have been conducted at 4 study sites. The transect method collected 11 families 119 species, whereas the trap method collected 5 families 22 species. Trapping increased only two kinds of butterflies. Two additional kinds of larvae species were found on tree plants during unscheduled survey period, Udaspes folus and Artipe eryx horiella, with a total of 11 families 123 species, and 8,235 butterflies. Results of Shannon Weiner biodiversity index indicate that for open land the highest is in June (2.93) and lowest in January (1.33); for crest line the highest is in May (3.42) and lowest in December (1.98); for forest margin the highest is in May (3.29) and lowest in August (1.72); and for forest land the highest is in June (2.81) and lowest in February (1.01). Significant change in the number of butterfly species occurs after 8 am and continues to increase in species and numbers towards midday when light intensity and temperature are higher. Butterfly activities reduction in the afternoon varies according to different environment. Under sheltered forest canopy environment, not only environmental factors change slowly, the frequency of butterfly activity is also slower than other study sites. These findings may vary differently in different seasons in the low lying areas in the northern part of Taiwan.
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