NORTHLAND NATURE: Nursery web spiders are noticeable in midsummer
As we leave July and enter August, we reach the time of midsummer. According to the calendar, the middle date between summer solstice and autumnal equinox is Aug. 6. This is when we notice more the earlier sunset and later sunrises. Days of nearly 15 hours of daylight as we begin August become about 13 and a half at the end. The bird song and nesting season is past. Exceptions to this are the never-tiring songs of the red-eyed vireos and the indigo buntings, while the goldfinches find the nesting materials they need and start their families now. Recently-fledged young travel among the branches with their parents at this time, slowly leading to migration. And tree swallows in flocks of hundreds are already on their south bound trek.
Elsewhere the goldenrods and asters, plants associated with late summer and autumn, have begun blooming along the roadsides where they share the attention with milkweeds, fireweeds, wood lilies and sunflowers. Nearby, the berry season continues. Raspberries, blueberries and juneberries with an occasional gooseberry and pin cherry add a taste of delight to my daily walks. Plenty of other berries are in the woods too, but we avoid consuming the ripe red and white baneberries or the blue ones of the blue-bead lily. A few days ago, as I paused at a raspberry bush, I noticed that I was not alone. A chipmunk was also here, finding these ripe morsels as delightful as I was. And on a nearby leaf was a small tree frog. The gray tree frog, now in its green phase as it sat on the leaf, reminded me of another midsummer happening: many of the tiny frogs and toads are now leaving the ponds. (Lots of vernal ponds are now losing water due to the evaporation of hot days.) I will continue to see plenty more in coming weeks.
But it was the sight of another critter on an adjacent grass plant that caught my attention even more so. Here, just a few inches away, was the large web-nest construction of a nursery web spider.
These spiders are regular residents of the Northland. Growing to a formidable size, the body is about one inch long, two inches with legs extended. They may be the largest spider that we will see in the region. This family of spiders include those that live at the water’s edge. Called fishing spiders, they are often seen moving over the surface of the water. Sometimes these eight-legged critters come up on shore and may climb buildings or docks; hence their other name of dock spider.
What I found on this summer day was one that climbed upon this large clump of grass with her egg sac and went into hiding. She bent over leaves and used her webbing material to make the structure more protected. Once the eggs hatch, she leaves this enclosed site to the numerous tiny spiderlings. She goes from this hiding place, but being a dedicated mother, she remains nearby to guard the growing family. On a stem nearby, the mother nursery web spider sits, keeping a vigil. Her ample size and banded-striped pattern is hard to not notice. Just her presence is enough to deter possible predation.
I expect to find such a nest every summer. I have seen them as early as from mid-July to late August, typically about the middle of this season. Nests, with all the threads of her webbings, can be up to several inches and are often much bigger than our hands. I find them mostly among the bent and folded leaves of raspberry and milkweeds, but if these plants are not available, they will make use of the grasses that grow so tall at this time along the roadsides and meadows. As happens with many spiders, what I was seeing here was the adult female. Males are smaller and I have never seen one near one of these large web nests. The name of this spider species comes from these big nests with her nearby.
Despite its size, this spider is harmless to us. She is concerned with the safety of her young and maybe getting a meal for herself, but is not interested in the passing human who stops to examine this interesting midsummer resident. Babies will grow and disperse from this home and eventually she will move on to resume her summer hunting of insects. Even though she makes an impressive web construction over the egg sac, she does not make a web for catching food. Instead her kind pursues prey on foot. I have seen a few in the garden. I expect to see more of these interesting spiders and their nursery webs in coming weeks as we go through this fascinating month of August.
Retired teacher Larry Weber of Carlton is the author of several books, including “Butterflies of the North Woods,” “Spiders of the North Woods” and “Webwood.” You may contact him at firstname.lastname@example.org.