Northland Nature: The crab spider on the wall
Retired teacher Larry Weber, a Barnum resident, is the author of several books, including “Butterflies of the North Woods,” “Spiders of the North Woods,” “Webwood” and “In a Patch of Goldenrods.” Contact him via Katie Rohman at firstname.lastname@example.org.
During January in the Northland, we obviously take note of the snow conditions, always on the lookout for the next storm. And the temperatures that frequently drop to zero degrees and below forces us to deal with nature around us. We may need to alter our plans or behavior while commuting in winter weather.
Our neighboring wildlife copes with the cold as well, many of which remain active. We expect to see birds at the feeder and find the tracks of active wintering mammals. These warm-blooded wildlife remain well insulated with feathers and fur. But we do have some of the smaller critters that are also active in winter: insects and spiders.
During a few of the mild days a month ago in December, I paused in my walking in snow to observe a small fluttering insect. At first, it looked a lot like a mosquito — an insect that we are quite familiar with. But at this time, with temperatures in the 30s, it was not a mosquito, but a cousin — a type of crane fly.
About the size and shape of a mosquito, these winter crane flies reach maturity in this season and flutter about as expected.
Also, while crossing the ice of a swamp on another day, I stopped when I saw movement of a small critter on the frozen surface. Looking more closely revealed a wolf spider. Slowed by the cold, it was persisting in its crawling to nearby snow. Wolf spiders remain active all winter in the subnivean zone beneath the snow. Insulated by the snowpack, they are able to move about here throughout the cold. Occasionally, they come to the surface, walking on the snow.
But there are times when we’ll see insects and spiders indoors. It is not unusual to see the activities of house flies and ladybugs in our house. We may not appreciate them, but with an interrupted sleep or dormancy, they don’t want to be here either. Ants showing up are a little different. They remain active in winter in sheltered sites (normally underground) and may wander into our homes, searching for food.
Besides these insects, their predators, spiders, may be present, too. Every winter, I expect to see two web-making spiders in the house.
In corners of the basement frequently are the triangle-shaped webs of funnel-web spiders (agelenids). They may remain for weeks waiting for meals to come by, and their webs may last for months.
Read more about spiders:
Northland Nature: Wide world of web-watching
Northland Nature: Lichen spider comes to stay
Northland Nature: Seeing spider travel threads in fall
- Larry Weber's journey to web-watching
Cellar spiders (pholcids) are so well adapted to human habitats that they almost never live elsewhere. They make webs usually near the ceiling. Here, they catch prey and they also continue to make egg sacs all winter.
Spiders that do not make webs may be a little less common indoors, but recently when I saw movement on a wall, I examined it more closely. Since it had outstretched legs, I could tell that it was a climbing crab spider (philodromid). Crab spiders are well known to be in flowers where they use their camouflage to do sedentary hunting of visiting insects. The climbing crab spiders are more active in their pursuits. Outdoors, they are often found in trees.
Coming indoors, they do the climbing again, this time on walls. I watched it carefully for a while as it moved along the wall. I wished it well and hoped that “Phil” would have a good winter in the shelter of this house.