Chapter 6: Evacitas 209
that the Philippines recognizes the need to protect cetacean populations from depletion. Unlike fish and other marine species, cetaceans and all other marine mammals are very vulnerable to depletion because of their very low reproductive rates. They produce one young at a time after a gestation and nursing period that lasts for as long as four years. Most species mature sexually at ages six to 12 years. Hence, their population cannot withstand a mortality rate exceeding more than a few percent a year without a decline in population. For the same reason, a population takes a long time to recover. In cases of population depletion or extinction, the situation may be irreversible notwithstanding all efforts to restore it. Perrin (1994) lists the following reasons why people should be concerned with the condition of cetaceans: 1. Cetaceans are part of the fishery resources by themselves. In countries like Japan, India, Sri Lanka, Norway, Spain, and the United States, some of these species are consumed as food. If they are driven to a point of extinction, the possibility of using them as food source is lost. 2. Cetaceans are part of natural systems that function in ways that humans are not fully aware of. In the eastern Pacific, for example, the population of tuna is bigger than it would otherwise have been if not for the species’ symbiotic relationship with dolphins. 3. Cetaceans are valuable in tourism and education. In countries like Australia, Japan, and Mexico, whales and dolphins in the wild attract very large numbers of tourists who spend considerably for the chance to watch them, resulting in substantial economic benefits to the local economy. Whalewatching and similar activities are also opportunities for tourists to learn about the history and culture of the local community. The fact remains that dolphins and whales are vulnerable to depletion and require better treatment and management than most other marine resources. Whalewatching as a management strategy Whalewatching is a worldwide industry accepted as a “sustainable use� of cetacean populations, compatible with Agenda 21 of the 1992 Rio de Janeiro United Nations Conference on Environment and Development (IFAW et al. 1997). It began as a commercial activity in 1955 in North America along the Southern California coast. As of 1995, more than five million people in 65 countries and overseas territories had engaged in whalewatching (Hoyt n.d.). Monetary returns are estimated at US $504 million per year and have nearly doubled since 1991 (IFAW et al. 1997).