Since 2001 JBL has been undertaking its own research expeditions to the original homes of our terrarium dwellers. With the help of measuring instruments all biotope data is logged and measurement errors are eliminated by the multiple measurements of theexpedition members.
Don’t forget that measuring results made with different manufacturers’ devices are not easily comparable! And devices with sensors are a particular problem: a UV-B sensor made by Gröbel (Radiometer RM 12) indicates another value than – let’s say - the popular solar meter from USA’s Solartech Inc. during the measurement. The reason is NOT the inaccuracies of the measurement or the bad quality of the devices but the “response characteristic” of the sensors:
NO UV sensors start abruptly at e.g. 315 nm; they slowly increase at 280 nm to a maximum at 300 nm and then slowly drop to 315 nm again. Their response characteristic corresponds to a wave. Other devices also show a wave structure but a more steeply increasing or decreasing one. That’s how it can come to MASSIVE differences in the results.
We have made a key observation after twelve expeditions around the world: the data varies from year to year, but more from season to season. In the rainy season biotope surveys naturally result in different values than during the dry season. But microhabitats also play an important role: a clearing in the rainforest can drastically change the climatic values compared to a shady location under a dense tree population, although they are only 100 m apart.
UV measurements
South America, Rio Negro near Barcelos, April 2009
| Hour | Weather | UV-A mW/cm2 | UV-B mW/cm2 |
|---|---|---|---|
| 7:00 | cloudy | 0,2 | 0,0 |
| 9:00 | partially cloudy | 1,3 | 0,04 |
| 10:00 | partially cloudy | 1,9 | 0,06 |
| 12:00 | cloudy | 2,2 | 0,09 |
| 16:00 | cloudy | 0,3 | 0,0 |
Vietnam, Nha Trang, May 2013
| Hour | Weather | UV-A mW/cm2 | UV-B mW/cm2 |
|---|---|---|---|
| 15:00 | partially cloudy | 0,5 | 1,51 |
For comparison Germany, Neuhofen June 2013
| Hour | Weather | UV-A mW/cm2 | UV-B mW/cm2 |
|---|---|---|---|
| 15:00 | partially cloudy | 0,82 |
Australia, Atherton Tablelands, October 2015
| Hour | Weather | UV-A mW/cm2 | UV-B mW/cm2 |
|---|---|---|---|
| 16:00 | cloudless | 0,61 | 0,12 |
Australia, Outback near Kata Tjuta, October 2015
| Hour | Weather | UV-A mW/cm2 | UV-B mW/cm2 |
|---|---|---|---|
| 08:30 | cloudless | 1,9 | 0,46 |
| 09:30 | cloudless | 2,05 | 0,54 |
| 11:00 | cloudless | 2,26 | 0,68 |
| 12:00 | cloudless | 3,36 | 1,28 |
Air temperatures/relative humidity (in the shade)
The temperature measurements on the different surfaces the reptiles sit on, are also interesting. A laser temperature-measuring device is easy to use and provides accurate measurements within 1-2 °C.
French Guyana, September 2004
South America, Rio Negro, April 2009
Malawi, September 2006
