A.T.M. Hassanuzzaman
Senior Scientific Officer
VPD,BARI,Gazipur
Md. Shah Alam
Senior Scientific Officer
VPD,BARI,Gazipur
During Boro and T. aman season, only 19 and 4 small mammals were captured respectively, in community trap barrier systems(CTBS). Throughout the year, 85 individual rodents moved from the village to the field while 82 individual moved from the field to the village. Both CTBS and linear trap barrier systems (LTBS) were proved to be ineffective for controlling rodents in Bangladesh.
Assessment, community trap barrier systems, linear trap barrier systems,
Comilla and Gazipur
Pest Management
To (a) examine the temporal pattern of captures of the main field pests (B. benegalensis), and
(b) investigate the pattern of damage to the CTBS structure and trap crop by this species.
Two villages of Comilla were selected to conduct this study. In each village we constructed one CTBS and three LTBS in each of the two main rice growing seasons in 2004 (Boro and T. Aman). The LTBS were placed along the margins of rice cropping areas where these abutted against village habitat (2 per village) or upland vegetable fields (1 per village). The CTBS were constructed around existing rectangular field plots and positioned centrally in large areas of rice fields but close to areas of high rodent activity (e.g. upland habitat). They varied in size and shape but averaged around (75 X 75) m. We selected fields that were to be planted with fast maturing rice to optimize the ‘lure’ effect. The same or adjacent fields were used for the two cropping seasons.
The CTBS and LTBS barriers were constructed from bamboo stakes, medium density opaque plastic sheeting and a continuous strand of thin wire to suspend the top of the plastic. The plastic was nailed to the bamboo stakes and stapled around the wire. The plastic was buried in a trench dug to a depth of 40 cm and stood to heights of 50-75 cm above ground. Because of the ‘micro-terraced’ nature of the field systems it was not possible to construct a ‘moat’ around the CTBS fence. Single cone multiple capture traps were held in place by bamboo stakes. CTBS units had 8 traps (2 per side). TBS had from 9-14 traps, depending on the length of fence. Observation on trap success was taken everyday. The trap number was recorded for each capture to provide a measure of directionality of movement.
VPD Annual Report-2004-05, BARI,Gazipur
Thirty thousand
CTBS:
There was a slightly higher number of captures in the Boro crop (19 mammals) than the T. Aman crop (4 mammals). The small number of captures was not due to a lack of rodent activity in the vicinity of the CTBS. In both villages, burrow systems of B. benegalensis were present in the adjacent upland habitat and numerous fresh track-ways were observed alongside the CTBS fences during field visits. The T. Aman rice crop typically experiences higher rodent damage at Comilla. In both villages, a high incidence of B. benegalensis burrowing under the fence during the latter part of the T. Aman season was observed when the field areas lack standing water.
LTBS
The LTBS units were more successful overall in capturing rodents and other animals In both villages there was a marked contrast in capture rates between the Boro and T. Aman cropping seasons, with higher captures during the former seasons. This contrast is particularly marked in the case of the two major field pests (B. benegalensis and R. rattus species. Boro season captures in both villages were considerably higher during the first half of the season than the second half. The CTBS method as implemented in this trial is not an effective method of rodent control in the Comilla rice cropping system. The LTBS was quite effective at catching rats during the first half of the Boro season but less so at all other times.
Report/Proceedings