Spring adders; not the friendliest of snakes!

A year after I wrote the last post on adders, I was out looking at their overwinter spot again. Contrary to the case in the US, the winter here has been very mild, with many adders surviving the winter.

Viper (Vipera berus)

The males are now out, waiting for the females to emerge, in hope of mating opportunities. The males are pretty agitated and probably all fueled up to take on other males in the fight for mates, so they are quite interesting to approach.

Viper (Vipera berus)

Even if the temperatures are barely above freezing, the few sun rays that get through heat the males enough for them to do quite a display if one comes to close. Hissing, “cobraing” up and even attempting to strike is the main greeting one gets.

Viper (Vipera berus)

Maybe the females will show up soon, and hopefully they will be a bit more friendly! At least, they can not be more annoyed than the males. Then again, in a few weeks they will all have spread into the surrounding forests and will be very hard to find. So, I guess, rather an angry, hissing, unfriendly male than no adders at all!

Viper (Vipera berus)

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European adder close to the arctic circle

I live quite close to the arctic circle. That means that summers around here are very sunny, and even at times quite warm. However, most of the year is cold to very cold. As an example, there will still be serious amounts of snow even entering May, indicating that most of the year up here is really on the chilly side. As the snow comes Novemeberish, we have around 6 months of snow cover in the area.

European adder
European adder

So how about reptiles? We actually have three species of reptiles, and one of them, the European adder, is quite common in this area. As anyone even remotely familiar with the requirements of reptiles know, six months of snow cover is not really the kind of habitat one would expect to find snakes in. On the other hand, this environment actually ensures that it is very easy to observe adders in.

European adder
European adder

Adders need to find above zero degrees winter hibernating places. Such places are often large rocky escarpments with crevices deep down in the ground. Down in the crevices the snakes from quite a large area gather and over winter in safety. During early spring, when the snow starts melting, the over wintering spots often are the first to become snow free, enabling the adders to get some early spring sun and get their systems running again. Due to slower melting speeds around the over wintering spots, and the risk of zub-zero night temperatures, the snakes are confined to stay close to the crevices where they spend their winter, and are thus easily found and observed. These pictures are from last weeks early snake expedition, where a single adder defied 4 degrees C and a chilly wind. It even got to be warm enough to be pretty aggressive and angry, which is quite a feat at that temperature. The next warm spell will probably find more snakes up, leaving them stranded in a slowly melting sea of snow. When the snow finally disappears, the adders will disperse in the forest, using the four months or so that are reasonably warm for a snake around here to eat and get fat enough to reproduce and also survive the coming winter. Reptile wise the life of my neighbouring adders will be as much on the edge as any reptile ever can achieve.

The weirdest thing

During a recent trip to Borneo, I participated in an inventory of frogs in rainforest streams. When searching for frogs along streams of Borneo, usually something really interesting shows up on the banks of the stream. This time we found something even more interesting than usual, a thing  I have never seen before despite numerous visits to this area.

_MG_6299It was a white, quite unstructured “thing”, suspended in silk threads inside a cage like structure. None of the participants in the inventory, including several field assitants that had worked in this part of Borneo for many years had ever seen anything like this. I had no idea what it could be and posted the picture on several web sites, hoping that someone would recognise the structure.

The power of internet is amazing. In just a day several of my colleagues had solved the problem. It turns out that this is the pupa of a certain butterfly. The butterfly is very hairy as a caterpillar.

Hairy caterpillar
Hairy Bornean caterpillar

Apparently, the caterpillar use its hairs to create the cage in which the butterfly hangs suspended during its pupa stage. One can only guess why this intricate behaviour has evolved, but a fair guess is that it in some way protects the pupa from predators or parasites.

_MG_6274
One of the evenings frogs

My first boxer crab

Boxer crab
Boxer crab on black sea cucumber, Bangka island, North Sulawesi

A couple of years ago I visited Bangka, a small island just outside the Lembeh strait on north Sulawesi for around a week. It was really low season at the time of my visit, and the resort had a mere four guests when I arrived. However, those guests were more or less leaving, and the owner with his family had some business to cater to outside of the island, so I ended up having my own dive resort including full staff for a number of days. After a couple of days, that became just a tiny bit to quiet for comfort, as I do not speak much Bahasa which was the going language in the resort. The great side of it was that I could by myself plan the dive spots every day without other people´s annoying wish for variation or beautiful coral sites! In other words, for several full days we could go all dirty and focus on cool macro subjects with no disturbing other goals.

One of my major wishes for this trip was to see a boxer crab. I had never seen one of those before, and really wanted to see one, and if possible get a shot of one. So, with a patience that defied belief, my poor dive guide (the patient one) and I (less patient, but I didn´t give up before he called it) ended each dive with around 20 to 30 minutes in the shallows looking for a boxer crab. And, as those of you that look for boxer crabs know, that is a lot of rocks to look under! We found loads of cool animals hiding, but to the increasing frustration of my dive guide and decreasing hope for me that we actually would find one, the days went. No boxer crab even the last day, even if we spent what I felt was hours on the last afternoon dive looking under rubble.

So, with all hopes on a boxer crab gone, we still had a night dive to do. The weather was not very good, windy and quite some surge going on, coldish even, and I almost canned the dive. But that has not happened yet in my dive career, and I quickly shaped up, turned on a stiff upper lip, got in the “a man´s got to do what a man´s got to do” mode and of we went. As the weather was pretty bad, we were dropped much to close to the coast in only around two meters of water. And, in a couple of seconds, the dive guides lamp went crazy,  blinding whatever nightlife was down there. We had been dropped right on top of a black sea cucumber with a feeding boxer crab on it. I am not really sure which one of us were the most happy, but the smile on the face of my quite young dive guide when we got out of the water indicated that he was at least very relieved to be able to finally deliver.