For Christmas this year Santa brought Freddie and Marabelle a new gift. First, some background. White's Tree Frogs are normally supposed to vary in colour between grey, green, and blue. However, you may have noticed that Freddie and Marabelle are almost always brown. Marabelle was brown when we got her from the store, but Freddie was definitely green when we brought him home from the store a year ago.

I have noticed that Freddie turns green again whenever we take him out of the terrarium, which happens when we do a complete cleaning once a month, and then he turns brown when we put him back in. So, there is something about the environment in the terrarium that makes him turn brown.

One night in the summer when it was very hot, we turned off all the lights in the terrarium. In the middle of the night, I used a flashlight to go looking for Freddie, and I found him sitting up on a vine near the top, and he was green again! So, I formulated a theory that the infrared heat lamps in the terrarium were affecting Freddie's colour.

Like any good scientist, I decided to test my theory by replacing the infrared heat lamps with another type of light bulb. At the pet store, I found some blue "Moon-Glo" bulbs that are supposed to mimic natural moonlight, so Freddie and Marabelle each received a Moon-Glo bulb for Christmas.

So far, my experiment has been unsuccessful. Freddie is determined to stay brown. There are other possible factors at work though, and hopefully I will get to test more theories as the year progresses. It could be the multi-spectrum fluourescent day lamp, or the radiation given off by the Moon-Glo bulbs, or the temperature, or the humidity, or even the scenery.

Anyway, here is a photo of Marabelle on the first night after I installed the new Moon-Glo bulbs. She seemed to enjoy them at the time, although she has been acting very lazy for the last few days, so I'm not sure what is up with her.

Technical details: This image was taken with my Rebel XT + kit lens at 55mm, ISO 1600, f/8 for 2.5 seconds.