Spatial dynamics of teak defoliator (Hyblaea puera Cramer) - Cochin ...

area. The trap was operated for a period of 16 months from 23 June 1993 to 15
October 1994. Daily collections of defoliator moths were made during the
period 1993-94. The outbreaks, which occurred during this period, were
mapped and the dates of start of these outbreaks were estimated as described
in Chapter 3. During this period, all the outbreaks that occurred at Kariem
Muriem were mapped and based on larval samples collected, the starting date
of each infestation was determined as described in Chapter 3. It was examined
whether moths were collected in the trap during the start of an outbreak so as
to judge if it could be used as a monitoring device.
7.3. RESULTS
The solar light trap developed was found satisfactory. Based on the
prototype model described above, a more convenient portable model was
designed with the following modifications:
1. The number ofsolar panels was reduced from 4 to 1.
2. The steel pole was reduced in size and was made collapsible.
3. The walk-in cage was replaced with a smaller cage.
The trap catch during the 16-month period is given in Appendix Band
depicted in Fig.7.2. along with the time of occurrence of outbreaks at Kariem
Muriem. Distinct period of abundance of moths in the field can be identified.
The period immediately after the establishment of the trap (June, 1993) was a
time of high abundance of moths. There was a decline in trap-catch during
August. There were further increases in the number of moths during the first
weeks of September and October. Only very few moths were collected during
November (2 moths) and December (1 moth).
In 1994, no moths were collected during January, February and March.
The first moth was collected on 2 April. Large number of moths were trapped
during the moths of May, June and July beyond which no moths were
collected until the end of the study in October. The correspondence between
the trap catch and the initiation ofan outbreak is depicted in Table 7.1.
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