Tuesday, February 10, 2009

Intercepting Surfers

This is a graphical representation of typical surfing and beach going attendance patterns over a day for many places in the world. Surfers tend to visit the beach in the mornings and evening - when conditions are best and they are not at work. On the other hand beachgoing tends to happen mostly in the middle of the day. Surfers also tend to visit the beach throughout the week or when conditions are good, where as beach going more typically occurs on the weekends.

Understanding this pattern is very important when considering the economics of beach going.

Many studies on the economics of beach going rely on intercept surveys to collect their data. Intercept surveys that take place in person at a site and interview visitors while they are at the beach. It is also during this time that many attendance counts are conducted to estimate how many visitors use the beach in a given day or year.

These surveys are often conducted in the middle of the day when beach going is at its maximum. In these cases a large portion of the surf visitation may be missed. This will lead to an underestimate of the overall use of the beach and also disproportionately miss surfer visits.

This could have many implications about the value of the beach and its management.

When calculating the lost value associated with the American Trader oil spill, Chapman and Hanemann avoided this pitfall by surveying beach visitors from 6 AM to 6 PM and found that at some Orange County beaches surfers made up 10-20% of the beach visits. This is one of the only studies on beach economics that specifically made an effort to survey early and late to capture surfers.

We found a similar patter at Trestles.