6/14/2023 0 Comments Arctic wolf spider![]() Clutch size for first clutches was correlated to female size, while this was not the case for second clutches. This is likely a result of female spiders producing their first clutches earlier in those years and allowing them time to produce another clutch. In years with earlier snowmelt, first clutches occurred earlier and the proportion of second clutches produced was larger. We found that assigned second clutches appeared significantly later in the season than first clutches. We tested whether the median capture date differed among first and second clutches, whether clutch size was correlated to female size, and whether the proportion of second clutches produced within a season was related to climate. Upon discovery of a bimodal frequency distribution of clutch sizes, as is typical for wolf spiders at lower latitudes producing a second clutch, we assigned egg sacs to being a first or second clutch depending on clutch size. We dissected individual egg sacs and counted the number of eggs and partially developed juveniles, and measured carapace width of the mothers. ![]() To determine if this is already happening, we used specimens of the wolf spider Pardosa glacialis caught by pitfall traps from the long-term (1996-2014) monitoring program at Zackenberg, Northeast Greenland. Yet the timing of snowmelt is advancing in the Arctic, which may allow some species to produce an additional clutch. Next step is to see how widespread the effects can become by scaling up to having plots throughout the Arctic.Spiders at southern latitudes commonly produce multiple clutches, but this has not been observed at high latitudes where activity seasons are much shorter. On the other hand, Koltz said, “If more carbon is released from the Arctic ecosystem, it would increase the rate of global climate change.” When there is less fungal activity, there is slower decomposition and less carbon released from the permafrost. If the fungi-eating springtails (collembolla) are no longer getting eaten, they are more abundant to keep the fungus in check. In a wet tundra, the fungus in the ground largely controls how quickly dead plant matter is decomposed. Springtails eat decaying plants and fungus. Under warming conditions, the wolf spider’s tastes shifted away from collembola, or springtails, triggering a chain reaction. Koltz and her team are manipulating the temperatures of some spider plots to show what may happen with global warming. As the Arctic warms, research shows wolf spiders may dine differently initiating a cascade of food web interactions that could potentially alleviate some impacts of global warming. Wolf spiders may play a role decreasing decomposition rates in a warming climate. Decomposition of dead plant matter in the Arctic contributes to global warming. The spider’s role with decomposition rates is a big part of the findings. The field research is taking place at the Toolik Field Station in Northern Alaska. Through her research, Koltz and her team discovered that Arctic wolf spiders may buffer some of the effects of global warming by helping to ‘keep it cool’. “Wolf spiders, just like humans and other animals, respond to changes in their environment, but they also can alter their environment,” Koltz said. They are also fierce hunters making them one of the most important predators in the tundra. In the tundra, wolf spiders outweigh gray wolves by several orders of magnitude. Koltz chose to study Arctic wolf spiders because they are abundant in the Alaskan Arctic. Arthropods seemed like a natural way to go because arthropods, insects and spiders, respond very rapidly to changes in temperature.” Koltz has a special interest in global warming. She said, “I’m interested in how climate change, and other forms of disturbance, is altering interactions between organisms. Koltz now works closely with wolf spiders in the Arctic. Ecologist Amanda Koltz said she didn’t like spiders when she was a child, but she has a whole new outlook as a postdoctoral research associate at Washington University in St. Spiders have a reputation for making some people’s skin crawl.
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