A spider that acts like a cat

If I were a dragonfly, wasp or bee flying over a lake in search of a place to land, I’d stay away from peelbark St. Johnswort, Hypericum fasciculatum, a yellow-flowering, shrubby plant that grows in and around wetland areas.

I’d be especially cautious September through November when female green lynx spiders living on St. Johnswort plants are guarding egg sacs and young spiderlings. Spiders are always looking to catch a flying insect that unwittingly lands on the wrong plant at the right time. That’s especially true when they’re raising babies.

And there’s a lot of baby-raising going on among arachnids living on plants in our lake right now.

Green lynx spider with egg sac on peelbark St. Johnswort

The other day while out rowing, I decided to take a survey of peelbark St. Johnswort shrubs and green lynx spiders, Peucetia viridians. Of the 340 plants I tallied, more than 7 percent contained a hungry and protective mama spider. Most of the spider-inhabited plants were located a short distance away from other St. Johnsworts, and I never saw more than one adult female arachnid on any plant.

Spiders were more likely to choose isolated plants like this one on which to raise young 

Since autumn is a green lynx spider’s reproduction season, each of the 24 spiders was either protecting an egg sac or guarding newly hatched spiderlings.

A green lynx spider’s egg sac is much easier to spot than the spider itself. The sac is a slightly bumpy, sand-colored container housing up to 600 bright orange eggs that will hatch within 11 to 16 days. The sac is about an inch diameter with one flat side and one rounded. After its construction is complete, the female spider surrounds the sac with a sketchy tent of randomly woven silky threads. She then protects it further by clutching it with her legs as she hangs upside down.

Lots of bright orange eggs surround this green lynx spider's egg sac along with a captured dragonfly 

Although birds may present the most obvious danger to lynx spiders, ants are a serious threat as well. Ants chew through egg sacs and carry away eggs. They can also attack adults. Perhaps choosing to raise young on an isolated plant in a waterlogged location makes it harder for ants to harm them.

Whatever their reason, female lynx spiders continue to protect their offspring until they can fend for themselves, which happens about 10 days after they hatch. When the young spiders are ready to leave, they do so by “ballooning.” They climb to the highest point they can reach, stand up on their hind legs and produce slim strands of silk that create a sort of a parachute to float them away on their random flight for life.

Green lynx spiderlings almost ready to 'balloon'

I have yet to observe spiderlings take flight, but I’ve marveled at the progress of egg sac development through the early stages of spiderling growth. I’ve also noticed a wide variety of invertebrates captured by female lynx spiders.

Wasp held in the clutch of a green lynx spider

Unlike spiders that spin webs, a green lynx catches food by leaping onto whatever hapless prey lands nearby. As its name suggests, this predatory arachnid has a cat-like ability to run fast and jump far. It also has keen eyesight, thanks to eight eyes positioned in such a way to monitor its surroundings from multiple directions simultaneously.

I like the way a green lynx spider’s well-camouflaged body make it hard to find unless you know where to look and what to look for. I admire the diligence with which females guard and protect their egg sacs, and I appreciate the way these relatively small spiders — females are a little less than an inch long with males half that size — fearlessly pursue prey far bigger than themselves.

Although just the thought of spiders strikes fear in many people, I think these eight-legged arthropods are beautiful creatures that provide an important service by eating insects that harm plants and bother people. Of course, not all the prey caught by arachnids can be considered a problem. Some of their victims are beneficial insects like potter wasps, honeybees and dragonflies.

That’s why if I were a dragonfly, wasp or bee, I’d stay clear of peelbark St. Johnswort plants — at least in autumn on small lakes in Central Florida. Doing so may not assure my safety, but it could prevent me from becoming the next meal for a green lynx spider.

One row...many pictures

If you're willing to look, there's much to see.

I just came in from a slow row around the lake's perimeter.  Much of what I found are just little things.  A pretty flower.  A tiny frog.  They could easily be overlooked. But if they were, so much would be missed.

Below is a glimpse into the world I discovered on my late afternoon row.

A pretty flower

A tiny frog, no bigger than my fingernail

Mama spider guarding her spiderlings

Looks like this orb weaver of the genus Neoscona
will soon be dining on a dragonfly wrap

This green tree frog looks like he's ready to leap from one pickerelweed leaf to another

Blue on green - A dragonfly that didn't get caught in a spider's web

And finally, this gulf fritillary butterfly looks like it has settled in for the night holding tight to its pickerelweed leaf bed

A dragonfly for Halloween?

It's almost the end of October so I suppose it's fitting to post a picture I recently took of a Halloween Pennant Dragonfly (Celithemis eponina) posing daintily on the curled tip of a spiderweb-adorned cattail.

Named for its orange and black wings (the Halloween part) and a propensity to flap in the breeze like a flag while attached to bare perches (the pennant part), the Halloween pennant dragonfly is a familiar sight on our lake.

I especially like this picture, however, not so much for the dragonfly - lovely though it is - but for the curled tip of the slender cattail reed upon which it chose to perch.  Something about that spiral curve sets my heart aflutter.  Combined with the Halloween pennant's pretty profile it becomes a special end-of-October picture.

Dragonflies...Yes. Mosquitoes...No

Dragonfly resting on redroot flower

SIMPLY LIVING

In the late afternoon, Ralph and I were sitting in the gazebo talking with a visitor when the topic of mosquitoes came up.  “Do you have many?” our guest asked.  With a lake within sight, I’m sure he imagined our response to be, “Yes.” 

Instead, we told him “No.  Thanks to dragonflies and bats, mosquitoes aren’t that bad here.”

Our response was reinforced that evening when Ralph and I took a pre-dark dip in the lake.  As we lolled in the sun-warmed water, a swarm of dragonflies filled the sky. 

“I don’t think I’ve ever seen this many dragonflies at once,” I exclaimed as a battalion of drone-sized fliers zoomed back and forth above our heads. 

The dragonflies were large – two to three inches long – and they flew with intention, showing no signs of hesitancy or indecision.  They didn’t land upon reeds as they do during daytime nor were they chasing each other in territorial battles or mating maneuvers.  Instead, they flew fast and furious, focused, it seemed, on a single mission: Catching bugs.  

I was awestruck watching them sweep across the lake, fortunate to be protected by troops of aerial warriors.

Red skimmer dragonfly on bog button

 

Between dragonflies and bats, which appear shortly after the dragonflies, the mosquitoes that live around our lake have much to fear.  Both consume quantities of bugs.  Although dragonflies and bats are both voracious carnivores, a dragonfly’s predatory skills are so well honed it manages to catch 95 percent of its prey.  In addition to mosquitoes, dragonflies also eat flies, gnats, bees, moths, butterflies and even the occasional spider in whose web they might find themselves entangled.

Bog buttons seem to be favorite landing pads for dragonflies of all colors and sizes

The wind wasn’t blowing as Ralph and I enjoyed our soak, and after the dragonflies appeared, it remained calm for about 15 minutes.  Then suddenly, a strong breeze blew in and our airborne navigators vanished.  We were still in the water a short time later (it felt too pleasant to get out) when the wind subsided and the dragonflies returned.  Around the same time, about half-dozen bats swooped in to do their sonar-directed search for supper above the lake and surrounding shoreline.

“Do you think we did anything to attract them,” Ralph asked as we dried off with towels on the way to the house.  We’d finally managed to extract ourselves from the lake’s warm water, leaving the dragonflies and bats behind to continue their feeding frenzy without a human audience.   

Although I didn’t have a definitive answer to his question, I presume dragonflies and bats live on our property because they find the habitat suitable.  There are plenty of dead trees for cavity-roosting bats to live in, shallow, marshy areas for dragonflies to frequent and no harmful pesticides or herbicides to disturb natural rhythms.  I also realize their presence could just as easily be the result of chance.

A few days later, we once again found ourselves lolling in the warm water in the twilight hours after a busy day of work.  As usual, dragonflies flew overhead albeit fewer this time than before.

Close-up of blue dasher dragonfly

“I love watching dragonflies,” I said from my semi-submerged perch.  “I may not know why they’re here, but I’m glad they are.”

As daylight diminished, we headed inside for dinner, happy to know that while we were dining on a vegetable stir-fry, a contingent of natural predators was zooming back and forth above the lake feasting on meals of their own.

An abundance of dragonflies

A "Simply" Extra
I just came back from an interesting row.  I often see dragonflies when I'm on the water but during this evening's row they were especially active.

Eastern Amberwing dragonfly resting on a bog button

Scarlet skimmer (above and below) on more bog buttons

A beautiful Eastern pondhawk dragonfly

Atlantic Bluet Damselflies were all around!  

I'm by no means a dragonfly/damselfly expert but have tried my best to identify the ones I've seen.  If you believe I've misidentified any of these colorful winged beauties, please let me know.

Two easy ways to tell Dragonflies and a Damselflies apart:

Dragonflies rest with their wings open

Damselflies rest with their wings closed

Dragonfly eyes are on top of the head and often touch or nearly touch

Damselfly eyes are separated on the side of the face and don't touch