Long-term monitoring and the conservation of tropical wetlands: high ideals and harsh realities

Long-term monitoring of wetlands is an essential element of management for ‘wise use’. Indeed, the Ramsar Convention requires regular monitoring in order to detect changes in ecological character at listed sites. However, there are few examples of successful long-term monitoring in tropical wetlands. Monitoring schemes run into three kinds of difficulties: conceptual, logistical and political. To be effective, monitoring schemes must be carefully planned and designed. In practice, the questions to be addressed are rarely made explicit. Strictly defined, monitoring should assess deviations from a pre-set level so that appropriate corrective action can be taken. This assumes that good baseline information exists, and that we have sufficient knowledge of the system to set sensible signal levels. Neither is usually the case in tropical wetlands. This means that carefully focused surveillance (a time-series of systematic observations) is an essential first step. Providing resources and co-ordination for surveillance or monitoring is challenging over the long term, especially if the variables being measured require expensive analyses and highly trained staff. I suggest that surveillance or monitoring programmes should focus on likely threats, and ecological or economic concerns, should be as simple, robust and inexpensive as possible, should be sustained and consistent, and should involve local people and volunteers. If it is to be effective, monitoring must have a clear linkage to wetland management. Ideally, it should form part of each country's wetland policy. I suggest some variables that could be incorporated in sustainable long-term monitoring programmes. Two examples of successful surveillance work at Kenyan wetlands illustrate that the challenges involved in long-term programmes can, at least in part, be overcome.