Environmental Engineering Reference
In-Depth Information
3.3.2.2 Methods
Field work was conducted on site, between February and December (2009).
1. Stratifi ed sampling survey
The Bunyala rice plantation itself is large, but it has been subdivided into small rectangular
plots, which served as the individual grids on which samplings and observations were made
during the study. Each plot was delineated by soil embankment and occupied an average area
of 0.75 acre. Grids were selected for sampling following opportunistic observation of pesticide
poisoning there. Targeted bird species were partially identifi ed on the basis of the type of baits
set out. The number of targeted species was then recorded between the time that poachers put
out the bait in the plot(s) and the time that the carcasses of the poisoned birds were gathered.
Individuals that fl ew in during the 'waiting period', i.e., the duration that a poacher kept
away from the quadrant where bait had been laid (and also that passersby were directed to
keep off the poisoning site), were added to the total already recorded. This total represented
the observed sample for each of the species. The individuals that fl ew out during this same
'waiting period' were included in the number observed since they too were assumed to be
possible victims of intoxication. Once a poacher had gathered his kill, we approached and
asked if we could identify and record each of the species killed. In some instances we had to
estimate species from a distance to avoid unwelcome aggression from the poachers.
2. Questionnaires and interviews
We sought permission from locals to survey them, explaining that we needed information
about the bird poisoning industry to plan for the educational component of the study and to
identify potential alternatives to the practices of poaching and consuming the fl esh of poisoned
birds (since we believe that both pose risks to human health). Two kinds of questionnaire were
then administered for different respondent groups:
(a) Poacher/hunter questionnaire: administered to those who poisoned birds, to obtain information
regarding the manner of poisoning and to assess their attitudes towards their way of life.
(b) Consumer questionnaire: targeted members of the general public who purchased poisoned
birds/carcasses from poachers.
The questionnaire was administered a second time, targeting individuals not approached
during the fi rst phase of the study, to evaluate the level of awareness and the effect (if any) of
our attempts to 'educate'. Additional information was also obtained during informal question
and answer sessions.
ii. Thin Layer Chromatography (TLC) analysis
A selected number of bird carcasses (n = 10, including one bait sample) were collected from
the poisoning fi eld while others were purchased directly from the poachers, (to avoid bias), for
laboratory testing. Nine avian carcasses were eviscerated (i.e., the guts were removed), stored in
glass tissue jars then kept frozen on ice in a cool box and transported to Nairobi for carbamate
analysis (using TLC) at the Government Chemist Laboratory. A sample of the pesticide-laced rice
bait/granules collected from the container in which the poacher's bait was stored was also tested.
3. Educational component
The educational component of the study was conducted to enhance local people's
appreciation of birds and their knowledge about pesticides, particularly Furadan, which
had previously been established as the product of choice to poison birds in an earlier study,
and during preliminary interviews and physical examination of poison baits for this study.
Two local scouts were trained to identify and count (poisoned) birds, and to estimate the
numbers in large fl ocks. The author, with the assistance of the two scouts, also educated
other locals on the potential repercussions of Furadan to people and wildlife, mainly during
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