Clevo Wilson (PhD Student 1995-98)

Each year thousands of farmers handling and spraying pesticides on their farms are exposed to pesticides and suffer from numerous morbidity effects ranging from headaches, nausea to cramps and body tremors. Long term effects and mortality due to direct exposure to pesticides is also not uncommon. The Ph.D field study was undertaken to collect data on all aspects of pesticide poisoning among farmers, and socio-economic data. From the data that was gathered it was possible to estimate the private costs to farmers arising from direct exposure to pesticides in Sri Lanka and also to determine certain relationships using regression analyses.

A field trip to Sri Lanka was undertaken in 1996 to collect the above mentioned data. The basic objective of the sample design was to obtain a representative cross section of farmers to base inferences about pesticide use and the numerous health effects and costs arising from such use. The period from June 1995 to June 1996 was considered. Five areas were sampled from the intermediate and dry zones of Sri Lanka, where intensive agriculture is widespread. The regions covered were Yatawatte, Kandalama, Beligamuwa, Ambana and Polononaruwa in the central and north central provinces of Sri Lanka, within a 75-100 mile radius.

The areas were visited during a three month period, July, August and September, 1996. Four local interviewers with experience in conducting interviews, were used in the study, each read dialogue and questions from the interviewer version questionnaire. The inerview time ranged from 50 - 90 minutes. Immediately after concluding the interview, some additional time was spent checking out the answers for completeness of questionnaire information and to review and edit interviewer notations.

Judgement sampling was employed to collect the data necessary for the study. This was owing to the impossibility of carrying out a simple random sampling study for the entire country due to financial and time constraints. Instead, judgement sampling was resorted to according to the information and advice given by officials of the Department of Agriculture.

The questionnare designed for the Ph.D study is a largely modified, Brien et al. (1994) questionnaire. The questionnaire is divided into nine sections with an introduction. The sections covered in the questionnaire are: The inroduction, information on pesticides, awareness of pesticide poisoning, short term private costs resulting from pesticide use, private costs on non spraying days, long term costs on pesticide pollution, precautionary and defensive costs, contingent valuation question and socio-economic data.

Two hundred and twenty four interviews were completed in the field from all the five regions. All but two of the respondents were male. From each region a minimum of 32 farmers and a maximum of 65 farmers were interviewed.

Only farmers who are regular pesticide users and cultivate land not less than half and not more than three acres were selected. Large scale cultivators of land were not considered. The five regions also specialize in growing certain food crops. As a result, the level and intensity of pesticides used and the level of direct exposure to pesticides vary from region to region. Also due to the type of crops they cultivate, often high yielding varieties, these farmers use pesticides for at least two cultivating seasons. Hence, the level of hospital admission or consultation of a doctor can also vary. It was found that rice farmers used fewer pesticides than their vegetable growing counterparts. Futhermore, the frequency of pesticide use varies from season to season. In the mostly rice growing season (known as Maha), the frequency of pesticide use is less than in the more drier vegetable growing season (known as Yala). Farmers who use pesticides once, or twice a week (usually vegetable growers) were more vulnerable to suffer from acute pesticide poisoning than those farmers who used pesticides once a month or thrice for the entire cropping season (usually rice growers) and get admitted to hospital or take treatment from a hospital. This is evident in the data collected.

Based on the data collected from this field study it was possible to calculate the private costs of pesticide handling and spraying to farmers in Sri Lanka using three established techniques, namely the contingent valuation , cost of illness and the avertive behaviour approaches. Furthermore, from the data set it was possible to conduct regression analyses to determine relationships between pesticide use, ill-health, precautions taken and many other factors. In addition to estimating the private costs of pesticide use, many examples of externalities were recorded during the study arising from the use of pesticides on the farms. For example, herbicides used on onion plots to destroy weeds when spread to neighbouring farms due to strong winds destroyed the other crops which were not resistant to the herbicides used.

Current Research

Clevo passed his Ph.D. in 1998 and went on to take up a postdoctoral fellowship at the University of Queensland, working under the supervision of Professor Clem Tisdell. Clevo was recently awarded (December 2000) our Postgraduate Essay Prize for the best paper based on PhD or MPhil work in the session 1999-00. He recently wrote to us as follows:

"My time here has been extremely productive with several articles and book chapters being accepted for publication and the rest being refereed at the moment. I do most of the work with Professor Clem Tisdell and I feel that I could not have got a better place. I have learnt a lot to date especially in the art of publishing articles. We have also been successful in attracting money for our research work. I also do teaching on Environmental Economics which is good."

Measuring the Touristic/Recreational Value of Marine Life in The State of Queensland, Australia

For the above mentioned Fellowship I hope to measure the touristic/recreational value of marine life in the State of Queensland, Australia. The State of Queensland is well located for such a study because of the abundance of marine life, which is rare and threatened elsewhere, and the huge touristic and recreational potential that this natural resource offers.

The research study will focus attention on the following areas.

Conservation benefits of marine life.

For this purpose, the necessary data would be obtained from the relevant institutions such as the Department of Wildlife, the respective national parks and conservation areas, holiday resorts, and other institutions that maintain records and statistics.

Furthermore, a user friendly mail questionnaire would be designed to collect data that is unavailable with the relevant institutions, for example, for measuring future and intrinsic values of marine life. The questionnaire would also be used to gather data to measure the value of Queensland's marine national parks. For this purpose, two valuation techniques developed to measure the value of environmental commodities would be used. They are the Travel Cost and the Contingent Valuation approaches. The theory behind these approaches would also be examined.

To administer the mail questionnaire, the co-operation of the wardens of the national parks would be sought stating the benefits they could also have from such a study. The mail questionnaire would be administered to a sample group of visitors in all marine national parks and sanctuaries for a selected period of time, both during the season and off season periods.

It is also hoped to examine the costs of protecting such marine life, for example, the administration of national parks, research, etc. and to conduct a cost-benefit analysis. The contribution made by this natural resource to the tourist revenues of the State of Queensland would be examined. This can be used to demonstrate the importance of protecting this valuable natural resource for future prosperity. Possible means of further enhancing and utilising marine resources in the State would also be discussed.

Publications

Wilson, Clevo, 1997. Book review: Wings in the Wetland: a photographic portfolio.
Bull. OBC: 26 (November issue)
A Rubythroat publication.

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