Back to Back Issues Page
Orb Weavers
October 07, 2019

New Guinea Impatiens, still growing strong.

Instant Fall.

Too much rain, much cooler temperatures, and the daylight sure are growing short real fast these days.

It is difficult get outdoor chores done when it keeps raining in inches.

Oh Well.

I'm never in a hurry to prune, pull and put yard art away.

When the weather has allowed me to be outside, or have windows open, I do get to enjoy the sites and sounds of nature.

Canada geese are practicing to fly in formation.

Family groups are now beginning to join other families.

On occasion, I hear and then spot a small to medium flock of Sandhill cranes as they slowly meander southward.

A second batch, or late batch of American goldfinches fill the yards with feed my cries.

What should be one of the last batch of Northern cardinal fledglings have also joined the cries for feed from their parents.

Yes, this late in the season, every year in my part of this land.

I still spot an occasional Monarch (hurry home), and Painted lady.

Sadly, hummingbirds are gone.

Do take care of my hummers as they migrate south.

At the bottom are pictures of Sophie on a box, there is not a box she doesn't find interesting.

Also, a picture of Snickers napping.

You may notice that spiders are in abundance this time of year as well.

I can't say I have ever done an article on spiders.

At All.

This is about to change, as I touch on a specific type of spider.

Orb Weavers.


Spiders that build webs are perhaps the most well known and easily observable.

The classic orb web is found in prairies, on fences and buildings, and in woodlands.

The Orb Weavers of the north overwinter in egg sacs or as very small spiderlings.

Therefore, orbs are very small in the spring and early summer, but increase in size through late summer and fall.

Evenings in late summer and early autumn are excellent times to see the Orb Weavers in action.

They often build a fresh web in the early evening hours and then sit in the middle of the orb waiting for prey to hit the web.

During the day Orb Weavers often hide under leaves or branches.

Sometimes they hold a single silk thread still connected to the middle of the orb to sense any prey that might hit the web while they are hiding from their own predators.

Orb Weavers (Family Araneidae):

Body Length: 1.5 to 30 mm

Orb Weavers are the spiders most people think of whensomeone says “spider.”

This is a large and diverse family.

While size, shape, and color vary greatly, common characteristics of the family include a small cephalothorax, small eyes, and large globular abdomen.

Males are much smaller than females.

All spin vertical orbs to catch flying prey.

Nocturnal Orb Weavers often build new webs in the evening, hunt all night, and then eat the web in the morning.

Diurnal Orb Weavers make the fresh orb in the morning for day use.

Eating the orb not only recycles amino acids and othernutrients used to make the web, but also provides an extra snack of all the tiny insects that were trapped but were too small for the spider to notice.

Orb Weavers are found anywhere there are flying insects andstructures across which a web can be spun.

The spiders sit in the orb upside down, sensing trapped prey through vibrations of the web.

When the Orb Weaver feels threatened, it often drops from its web and becomes almost impossible to find in the vegetation.

Sometimes the spiders build a silk retreat in a nearby hidden location like a rolled-up leaf, branch crevice, etc. but still maintain communication with their web through a silk thread attached to the middle of the orb.

The prey is usually flying insects such as flies, bees, wasps, beetles, and so on caught in the web is held with the front legs while the rear legs wrap it in silk.

Once immobilized, the prey is bitten to inject venom.

The wrapped prey may be eaten in the middle of the orb, taken to the spider retreat, or hung in the web to eat later.

(Feeding on a fly while another is caught in the web.)

Spiders’ Ecological Role:

All spiders are predators, feeding on any invertebrate species (including each other) that they are able to subdue using a combination of silk, venom, or strength.

While their predacious lifestyle dictates a solitary life, spiders are found in large numbers in all habitats throughout the year, though they are not usually active during cold weather.

Spiders are also are prey for a variety of toads, birds, and insect and worm parasites.

Spiders may be found in webs, running on the ground, climbing vegetation, or hiding in crevices under rocks and debris.

Spiders disperse by “ballooning” as young spiderlings (remember Charlotte’s babies).

On warm days with gentle breezes, thousands of spiderlings balloon leaving accumulations of ballooning silk on fences, bushes, and trees.

I have seen this once in my life, a few short years ago.

The silk is referred to as gossamer and the spiderlings are sometimes called gossamer spiders.

There are two peaks of ballooning activity, one in late spring to early summer and a second between mid-summer and autumn.

The ability to balloon allows spiders to disperse to new areas and also to re-establish populations after prairie fires.

(Feasting on a Bumblebee.)

Spider Bites:

Nearly all spiders have venom that is injected through theirfangs.

While Black widow and Brown recluse spider venom can be harmful to humans, these species do not regularly live in the prairies, savannas, or woodlands of northern states and provinces.

Some spider bites may be painful (not unlike a bee sting) but the fangs of most spiders are not large or powerful enough to penetrate human skin.

Spider Development:

(Approaching a Yellow jacket.)

Eggs are deposited in a silk egg sac that can be hidden, placed in the web, or carried, depending on the species of spider.

The spiderlings hatch within the egg sac and molt at least once.

This is a dangerous time for the spiderlings as they are confined to a small space with their hungry siblings!

Spiders are known to eat eggs in their egg sac that do not develop and even cannibalize slower-developing siblings.

Most of the spiderlings tolerate each other and restrain their predatory instincts until they disperse from the egg sac.

Spiders do not go through any type of metamorphosis; babieslook like small adults.

Spiders molt or shed their outgrown exoskeletons from 4 to 12 times during their lifetime.

At the last molt, the spiders become reproductivly mature and males can be distinguished from females by their enlarged pedipalps and, usually, smaller size.

(Feeding on the Yellow jacket.)

Spider Courtship & Mating:

After molting to maturity, males wander in search offemales.

Once a mate is found, the male uses a variety of displays including dancing, web “plucking,” drumming on thesubstrate, and sound to convince the female that he is the right male for her and not a meal.

If the female is convinced, mating occurs and the male usually makes a hasty retreat but is occasionally eaten by the female.

Since the males are short lived and may not mate again, their bodies can provide important nutrition for the female.

The female stores the sperm until she is ready to fertilize the eggs and deposit them into an egg sac.

(Look carefully and you can see the details of the web.)

Spider Silk:

Silk is one of the defining characteristics of spiders.

Spider silk is one of those products of nature that mystifies and amazes humans.

Scientists have yet to synthetically produce a material (not even steel!) that has the incredible strength and elastic properties of spider silk.

Spider silk is produced as a liquid in silk glands located in the spider’s abdomen.

Well, it is time to fly for now.

Before I go, here is your positive thought for the week.

God Bless.

"The mediocre teacher tells. The good teacher explains. The superiorteacher demonstrates. The great teacher inspires."

William Arthur Ward

(I like this quote.)

Did you have a teacher(s) that inspired you?

Jesus taught and inspired others.

"I no longer call you servants, because a servant does not know his master's business. Instead, I have called you friends, for everything that I learned from my Father I have made known to you."

John 15:15

"Treat the earth well:

It was not given to you by your parents,

It was loaned to you by your children.

We do not inherit the Earth from our

Ancestors, we borrow it from our Children."

Ancient Indian Proverb.

A Blessed week to you .

Your friend indeed,

Ron Patterson

PS. If you enjoy these letters, please forward them to friends, family and co-workers.

Better yet, have them sign up so they can receive their own letters.

Gardening For Wildlife.

Back to Back Issues Page