Ever since my daughter was a little girl, she has been fascinated with the natural world. It mattered not whether we were on vacation or just exploring our backyard, her inquisitive mind and sharp eyes enabled her to find something fascinating wherever we happened to be. More often than not, she would be the first to make such a find. As such, on a recent visit, it was no surprise that, while walking around the deck of our home with my wife, she spotted something hanging from beneath one of the deck rails. Immediately she exclaimed, “What is that?
Below one of the rails, she just happened to notice what looked very much like a small, brown paper bag measuring an inch or so in diameter. The object was suspended from the rail by a number of slender filaments.
Within minutes, my granddaughter and I joined my wife and daughter on the porch. Each of us marveled at how well the small, round object was camouflaged dangling next to the deck’s brown wood.
As has been the case so many times over the years, finding a backyard treasure perked our curiosity. We just had to find out what we were looking at.
I suggested it might be a spider’s egg case. Armed with this possible identification, my wife searched the internet looking for photos of spider egg cases. In just a few minutes, she emerged from our home office and announced she was convinced it was a yellow garden spider’s (Agiope aurantia) egg sac.
I then retreated to my natural history library to learn more about the yellow garden spider and its egg sac.
Leafing through the pages of several books I learned the female yellow garden spider creates one to four of these impressive egg cases per year; most are constructed from late summer to fall. Working under the cloak of darkness she lays anywhere from 300 to 1,000 or more eggs on thin sheets of silk. She then wraps them up forming a tough, brown silk ball. The rugged covering protects the eggs from both the elements and predators.
In the spring, the young spiders emerge from the egg sac and venture out into the world. As you might expect very few of these tiny spiders survive long enough to reproduce. Some of the spiders eat each other, still others are caught by predators such as mud daubers and birds.
It was truly amazing how our daughter’s backyard discovery led to a memorable event shared by three generations of our family. In addition, it reinforced our appreciation for the amazing variety of life that lives just outside the backdoor.
I guess you can see why I will never tire of hearing a family member say, “What is that?”
I was scrolling through your previous postings and came upon this. I have several eggs in my yard, but did not know what they were, but was pretty sure they belonged to a spider as I have a couple around my house this summer. Thanks for this info. I was not about to bother them, just decided to wait and see what happens. I wonder where my spiders went as they simply disappeared over night. I had one just outside my kitchen window that I was watching.