Evaluating Tourism Carrying Capacity on a Heritage Island
A World Heritage-listed island of 12 km² receives 340,000 visitors per year, concentrated in a 4-month peak season. The island's resident population is 1,100. Infrastructure: one desalination plant producing 3.2 ML/day; peak-season demand is already 3.0 ML/day, with visitors using 60% of it. One sealed road; a ferry carrying 500 passengers per trip, 8 trips per day at peak. A survey found 68% of residents feel tourism 'has changed the island for the worse', and 41% of visitors said the island felt 'crowded' at key sites. The island's management plan caps daily visitor numbers at 2,800.
1. Calculate peak-season daily visitor numbers and assess whether the 2,800 cap is being exceeded.
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Step 1 - Average daily visitors across the year.
- 340,000 ÷ 365 ≈ 932 visitors/day on average.
Step 2 - Peak-season concentration.
- The peak season is 4 months ≈ 122 days.
- If, conservatively, 55% of annual visitors arrive in the peak season (a typical concentration for a seasonal destination), peak arrivals = 0.55 × 340,000 = 187,000.
- Peak daily average = 187,000 ÷ 122 ≈ 1,533 visitors/day.
Step 3 - Compare with the ferry capacity.
- Ferry capacity = 500 passengers × 8 trips = 4,000 arrivals/day maximum.
- If the ferry runs at 80% load in peak, that is 3,200 arrivals/day - well above the 2,800 cap.
Step 4 - Compare with the cap.
- The peak average of 1,533 is below 2,800, but the cap applies to daily numbers, and peak days (weekends, holidays, cruise-ship days) will be far above the average. If the ferry carries 3,200 passengers on a peak day, the island receives 3,200 visitors - 400 above the cap (14% over).
Conclusion: the cap is likely being breached on peak days even though annual averages look compliant. The island's management should measure daily arrivals, not annual totals, and should manage ferry bookings as the enforcement lever. A strong answer distinguishes average from peak and uses the ferry capacity as a cross-check.
2. Using the survey data and infrastructure figures, evaluate whether the island has exceeded its social and environmental carrying capacity.
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Environmental carrying capacity - water is the binding constraint.
- Supply = 3.2 ML/day; peak demand = 3.0 ML/day, i.e. only 0.2 ML/day (6%) of headroom.
- Visitors use 60% of demand = 1.8 ML/day. If visitor numbers rise even 10%, demand rises by 0.18 ML/day, leaving almost no buffer for residents, firefighting or a plant outage. The desalination plant is effectively at capacity, and expanding it has energy and marine- discharge costs.
- So on water, the island is at or near its environmental carrying capacity. The 2,800 cap is not derived from the water limit; it should be.
Social carrying capacity - evidence of strain.
- 68% of residents say tourism has changed the island for the worse - a clear signal that perceived carrying capacity has been exceeded. Resident population is only 1,100, so 340,000 annual visitors is roughly 309 visitors per resident, an extreme ratio.
- 41% of visitors feel crowded, meaning the experience quality is also declining - a sign that the tourism product itself is being degraded.
Synthesis: the island has likely exceeded its social carrying capacity and is close to its environmental (water) limit, while the daily visitor cap is being breached on peak days. The three indicators point the same way.
Recommendation: lower or enforce the daily cap (e.g. 2,200), spread demand into the shoulder season through pricing, cap ferry bookings to match the daily limit, and set a water-allocation rule that reserves a fixed share for residents. A strong answer treats carrying capacity as multi-dimensional (physical, environmental, social, perceptual) rather than a single number, and uses the figures as evidence for each dimension.