讀後心得

This year, the purple butterfly migrating from the south to the north arrived earlier, but the numbers are fewer. Chen Ruixiang, the chairman of the Taiwan Purple Butterfly Conservation Association, pointed out during a briefing in March that the advance party of purple butterflies appeared in Linnei Township, Yunlin County, at the beginning of March, setting a record for the earliest road closure in history. However, it only lasted for two days, with only 160,000 butterflies recorded so far, which is below the historical average of 220,000. Since 2007, the conservation association has implemented road closure measures during the migration period of the purple butterflies to protect the butterfly population. It is expected that the purple butterflies will leave before the Qingming Festival, but the current observational numbers have not met expectations. Observations will continue.

This year, the speed of the migrating purple butterflies from the south to the north was early, but their numbers were relatively low. In March, the chairman of the conservation association provided explanations for children in a butterfly tent in Linnei Township. At the beginning of March this year, the advance troops arrived early in Linnei Township, Yunlin County, with counts exceeding 250 butterflies per minute for two consecutive days, meeting the standards for closing National Highway 3 and setting a record for the earliest road closure. However, during this period, only two days met the standard, with a total of 160,000 migrating butterflies so far, below the historical average of 220,000 butterflies.

Since 2007, the Highway Bureau of the Ministry of Transportation has implemented "highway butterfly passage" measures for the Linnei section of National Highway 3 during the purple butterfly migration period. When the migration count reaches 250 butterflies per minute, the outer lanes from 251 kilometers to 253 kilometers will be closed to reduce traffic flow damage to the migrating purple butterflies.

The Taiwan Purple Butterfly Ecological Conservation Association has stationed at the Chu Kou culvert section of National Highway 3 in Linnei since March. On March 4th, they recorded 210 butterflies per minute, and on the 12th and 13th, the counts exceeded the standard of 250 butterflies per minute for two consecutive days, setting the record for the earliest road closure ever. However, the subsequent migration seemed to decrease, and this year’s road closure days were also the fewest in history.

Based on past experience, purple butterflies typically leave Linnei Township before the Qingming Festival. The association observed over 300,000 butterflies in 2023 and over 400,000 in 2024, but the migrating count after this year's Qingming Festival was only 160,000, failing to reach the historical average. Chen Ruixiang stated that there were still some purple butterflies departing from the southern butterfly valley on the 4th, but in small numbers. The cumulative migration count is currently over 160,000, and it is hoped to continue observation until April 30, with volunteers conducting daily observations and butterfly counts.

Chen Ruixiang added that the temperature fluctuations before this year's Qingming Festival were significant, which might have caused some purple butterflies to remain in place. Additionally, no large-scale northward migration was observed on sunny days. So far, there has also been no record of large numbers of purple butterflies at the Zhunan observation point, and observations will continue this week.