Monitoring visitors to natural areas in wintertime: issues in counter accuracy

Abstract

The sustainable management of vulnerable natural areas requires accurate measurement of visitor flows, especially in mountain and protected areas. Pyroelectric sensors that detect the heat radiation emitted by human bodies are now commonly used in many regions, including Scandinavia and the UK, to count pedestrian traffic in both urban and natural areas. We used four different tests to investigate pyroelectric counters’ accuracy in mountain winter conditions. Air temperature, distance to sensor, visitor clothing and visitor volume were all found to affect counter error rates. For tests within moderate winter temperatures (between 0°C and −18°C) counters reported within manufacturer's claimed accuracy at 5% for 2 m range, but for −21°C and below visitor numbers were over reported by 10.9%. Counter accuracy was generally unaffected by visitor clothing within 2 m of the sensor, but at a 4 m distance counters frequently failed to detect individuals in insulating down jackets more than fleece jackets. Counter error rates were slightly higher in outdoor than indoor tests, but still accurate within 5%. Error rates increased with increasing visitor traffic. The findings provide methodological implications for researchers and managers using automated visitor counters to estimate wintertime visitor use in mountain areas.

对游客在冬季的自然区域里的监督：计数器精度的问题

脆弱自然区域的可持续性管理需要对参观者数量作精确的衡量，特别是在山区和保护区域。热释电传感器能检测出由人体散发出的热辐射现在在许多区域，包括斯堪的纳维亚和英国都经常使用，来计算在城市和自然区域里的行人交通。我们使用了四个不同的测试来观察热释电计数器在山区冬季条件的准确性。空气温度，离传感器的距离，参观者衣着和参观者数量都被证明会影响计数器错误率。在温和的冬天温度（零摄氏度到零下１８度之间）的测试发现，计数器报告是在生产厂家所说的准确度每２米５％的变化，但是对于零下２１度以下，参观者数量会被多报。计数器准确性总体来说在传感器２米范围内不受参观者衣着影响，但是在传感器４米范围，对穿毛衣的参观者相比，计数器不善于测出穿绝缘的羽绒衣的参观者。计数器错误率在室外要高过室内测试，但是仍然在５％内。错误率随着人流增长而增长。结论提供了为研究者和管理者使用自动参观者计数器来估计冬季在山区参观者使用的一些方法上面的意义。

Keywords:

• visitor monitoring
• protected mountain areas
• eco counter
• error rates
• Norway

关键词:

• 参观者监测
• 保护山区
• 生态计数器
• 错误率
• 挪威

Additional information

Notes on contributors

Oddgeir Andersen

Oddgeir Andersen is a research scientist at the Norwegian Institute of Nature Research (NINA). He holds an MSc in applied ecology and is a PhD student in applied ecology at Hedmark University College, Department of Applied Ecology and Agriculture. His research fields are man–environment studies, nature-based tourism, game management and balancing the utilization and conservation of nature areas.

Vegard Gundersen

Dr Vegard Gundersen holds a master's degree in forestry and earned his PhD in urban forestry in 2005. He is a senior researcher at Norwegian Institute of Nature Research, responsible for several large monitoring projects for recreation and tourism in Norwegian national parks using methods like GPS tracking, automatic counters and on and off site questionnaire surveys.

Line C. Wold

Line C. Wold holds a master's degree in nature-based tourism from the Norwegian University of Life Sciences. She is a research scientist at NINA, working with tourism in high mountain Norway.

Erik Stange

Dr Erik Stange earned his PhD in ecology and evolutionary biology. He is a senior research scientist at the Norwegian Institute for Nature Research. His research areas include landscape ecology, ecosystem ecology, ecological restoration and forest landscape management strategies.