Friday, May 29, 2015

Snapping Turtle Laying Eggs

A big turtle on a big ant hill is a pretty easy thing to see from a distance.  I didn’t even question my first glance identification of this object.  I just headed over to take a closer look.

Still sporting a coat of wet mud from the pond bottom, this female Common Snapping Turtle is in the process of excavating a cavity in which to deposit a load of eggs.  The process begins with a release of urine that both softens the soil and allows the hole to be dug without the sides caving in.

The turtle uses her hind legs to dig the hole, arrange the eggs, and cover her clutch.  She never sees what’s going on and does everything by touch.  The hole is dug to the extent of the turtle’s reach.  Larger turtles lay more eggs, but they also have a longer reach and excavate a larger hole.  This turtle measures about 13 inches from front of shell to rear. 

Once the underground cavity is completed, the turtle begins to lay eggs.  Eggs were dropped at a rate of one or two per minute until a total of about 30 eggs was reached.

After each egg was dropped, the turtle used her leg to sweep the area where the egg fell to make sure it made it into the hole.  Next she reached her leg down and pushed the latest deposit further into the cavity.

When the last egg was put into place, the turtle began stretching her hind legs far out and raking in loose soil with which to refill the hole.  Each scoop was carefully packed down until the soil in the hole was brought up to the level of the surrounding ground.

The ants had various responses to the disturbance caused by the turtle.  Some hurried to defend their nest.  Others collected water from the turtle’s body.  Ants biting around the turtle’s eyes caused her to give an occasional snap that had no impact on the activities of the ants.

Once the hole was filled, the turtle began moving up the mound.  As she climbed, she used all four legs to tear up soil and push it back in the direction of her eggs.  When she had finished, it was impossible to identify the exact site of her nest cavity.

The last bit of covering activity put the ants back into defensive mode and they swarmed the turtle.  I don’t think the turtle’s eyes were open for more than a few seconds the entire time she was on the ant mound.

No, she’s not dead.  This turtle has spent most of her life in a pond where her bulk is supported by water.  The effort to leave the water, construct a nest, lay eggs, and return to the pond requires a great expenditure of energy on her part.  Throughout the entire process, she would periodically go limp and rest a few seconds before continuing her work. 

During rest periods, the ants would calm down and go back to their water collecting activities.  May has been an extremely dry month at Blue Jay Barrens and the ants are taking advantage of every opportunity to collect fresh water.

After an extended nap atop the mound, the turtle revived and turned to face her home pond.

Off she goes, shedding ants with every step.  I just wonder how the eggs will fare in their ant protected incubator.

video
I’ve included a short video of some eggs being added to the nest.  A more complete video can be viewed on YouTube by clicking HERE.

Monday, May 25, 2015

Carolina Wolf Spider with Eggs

The entrance to the Carolina Wolf Spider burrow is surrounded by a small forest of White Clover.  I periodically prune back the leaves directly over the burrow, but try to make a minimal impact so as not to discourage the spider from maintaining its residence in the burrow.

When I sneak in to have a look at the spider, I usually end up seeing nothing but an empty hole.  A glimpse of quick movement beneath the clover leaves is my most common confirmation that the spider is alive and well.

This morning, I got a glimpse of the spider far down in her burrow.  She is sitting at a point where the burrow makes a sharp turn to the left.  This turn makes it easy for the spider to retreat completely out of sight.  I have been eagerly awaiting some sign that she has produced a clutch of eggs.  According to everything I have read about this species, eggs should appear this spring.

During my evening visit to the spider, I noticed this white object at the mouth of the burrow.

In typical wolf spider fashion, the spider has enclosed its clutch of eggs in a silk envelope which is now attached to her abdomen.  Where she goes, so go the eggs.

The eggs should hatch sometime next month.  Following a time enjoying the care and protection of their mother, the young spiders should leave the burrow and begin life on their own.  This is the event I’m hoping to witness.  It is unlikely that the young spiders will stream from the burrow in a single mass.  I expect there to be a period of time where young spiders will be seen exploring around the burrow entrance or moving around the general vicinity of the burrow.  It’s also possible that the young will make short excursions from the burrow and then retreat back inside upon sensing danger.  I’ll keep making a daily check.  If I’m lucky, I should see the family leaving home and striking out on their own.  To read earlier posts about this particular spider, click HERE.

Wednesday, May 20, 2015

Harvesting Draba Seeds

This could pass as a Martian landscape, but it is actually a portion of the seed I harvested today from my container grown Draba cuneifolia.

The container was so crowded with Drabas that the flower stalks had woven into one great mass.  Any attempt to harvest seed from one plant caused all of the neighboring plants to dump their seed load.  More than enough seeds had already fallen back into the container, so I had to find a harvest method that could effectively remove the remaining seeds from the plants without additional losses.

The Draba seed pod is divided into two halves with a thin, semi-transparent membrane running through the center.  Seeds are arranged in two rows on each side of the membrane.  When the seeds are ripe, the two outer coverings of the pod begin to peel back at the bottom, leaving the seeds exposed.  At this point, it doesn’t take much disturbance to cause the seeds to fall free.  In the past, I have harvested seed by simply bending the plant over a small cup and giving it a couple of taps.  The seed fell into the cup and that was all there was to it.  That method doesn’t work when the tangled plants all acted as one unit.

I decided to try using my shop vac as a harvester.  My shop vac is a bagless model, so I took a clean sweeper bag and modified it to fit the inlet pipe on the inside of the shop vac dirt chamber.  Then I directed the sweeper hose towards the plants and the seeds quickly disappeared.  The shop vac is not a high end model, so the air flow past the plants was really kind of gentle and did little more than pull away loose parts.  I just hoped everything was ending up in the bag. 
 

Fortunately, the sweeper bag stayed in place through the entire operation.  I sucked in a lot of seed pod covers, along with a little bit of dirt, but it looked like there was also some seed in the collection.

A closer examination revealed plenty of seed hidden beneath the seed pod parts.

I had to cut the sweeper bag in half to remove the seeds, but I was happy with the harvest.

Draba seeds are tiny things.  That’s a normal sized nickel beside the seed pile.

This is what I ended up with after sifting the mess through a screen to separate out the seed.  That’s five grams of fine Blue Jay Barrens Draba cuneifolia seed.  I couldn’t find any figures specifically for Draba cuneifolia, but similar Draba species average about 6,000 seeds per gram.  That means there are 30,000 seeds in this vial.  I’ll be scattering this seed back on the barrens in the same area from which I originally collected seeds for my container grown population.  I think I’ve repaid that loan of a few seeds with adequate interest.

Monday, May 18, 2015

Blooming Season Potato Dandelions - Three Days Later

It seemed likely to me that the Potato Dandelion flower buds seen a few days ago would be open today, so I made a trip into the woods to check.  I was suitably impressed by what I found.  All but one of the buds had opened.  On my previous visit to this site, the plant in the foreground of the above photo had three stalks topped by buds.  This morning there were two stalks with flowers.  The third stalk had disappeared completely.  I’m hoping the predator that removed that stalk has had its fill of Potato Dandelions.

The yellow bloom atop the tall stalk made it easy to find the plants.  I even found another cluster of plants that I hadn’t noticed before.

The ground wasn’t quite as bare around the new found cluster.  The leaf litter was only about one leaf thick though, so the plants had no trouble thrusting their leaves into the light.

I went down to the other end of the ridge to check on the original Potato Dandelion site.  This section of woods suffered a lot of damage from grazing cattle, and things are struggling to recover from that negative impact.  The cattle have been gone for over 30 years, but the Whitetail Deer are doing their best to take up where the cattle left off.  The deer have left a well developed browse line through the entire woods and are changing the composition of the forest understory with their overbrowsing of preferred food plants.

I was pleased to find blooming Potato Dandelions at the original site.  Four out of five years will find zero plants blooming here.  I noticed that the long term snow pack that existed in the woods this past winter had significantly compressed the leaf litter.  This may have made it easier for the plants to get their leaves out into the sunlight.

Whatever the reason, I counted 11 flowers at the time of my visit.  The only time this site has come near this number of blooming plants is when I’ve physically removed the leaf litter prior to the emergence of the plants.  It will be interesting to see if any of these flowers produce viable seeds.

This is how the plants look during a normal year.  Plenty of elongated leaves fall limply across the leaf litter like they were subjects in a Salvador Dali painting.

It looks like the flower count is destined to increase.  I found many plants that were just beginning to send up flower stalks.  When you are used to most years passing without a single Potato Dandelion flower, a year with an extended blooming season could prove to be quite overwhelming.

Friday, May 15, 2015

Blooming Season Potato Dandelions

Sunlight is a key factor in determining whether or not a Potato Dandelion, Krigia dandelion, will bloom.  Woodland populations receive much of their sunlight prior to emergence of leaves on the deciduous trees.  Even in mid-May, the tree leaves have not developed enough to completely block the sun.

Fallen leaves from previous years can also keep sunlight from reaching the developing plants.  Those plants that must push their way up through the leaf litter rarely bloom.  That’s one reason why I transplanted Krigia tubers into areas of sparse leaf litter.  Strong winds pushing over the ridge tops consistently push leaves away from certain areas.  It’s in these areas that the Potato Dandelions should prosper.  I should they could thrive if animals stopped eating them.  In this grouping of four plants, all have suffered some degree of damage from hungry plant predators.

This is the most common condition.  Leaves and flower stalks severely trimmed back.

This specimen lost nothing but a flower bud.  Since the flowers rarely produce any viable seed at Blue Jay Barrens, the loss of the flower does no harm to the plant.  As long as the plant is healthy, the roots will produce a nice collection of new tubers.

When I planted Potato Dandelion tubers into this location last summer, I placed them in groups of three or four.  This set of three plants represents the most successful grouping I could find this week.  All three have managed to grow without any predation.

The tuber planted here must have had exceptional vigor to produce three flower stalks.  The tubers produced from these three plants could easily result in 30 to 40 plants on this spot next year.

Judging by the amount of leaves being produced, the container bound Potato Dandelions are going to provide me with plenty of tubers to transplant to the woods later this summer.  These plants were caged a few weeks ago after some browsing animal ate all of the leaves.  The damage occurred prior to the development of flower buds, so there was no reduction in the number of blooms produced.

The original source of tubers for my container grown specimens was the ridgetop woodland at Blue Jay Barrens where the plants were found to be naturally growing.  By transplanting container grown tubers onto that same woodland ridge, I hope to expand the size of the population as insurance against some disaster destroying the original population.  I manage the plants and animals found naturally at Blue Jay Barrens and have made it a strict policy to not introduce any species from outside the property boundaries.  With luck, someday I’ll have clumps of these little beauties enhancing the entire 1500 feet of the ridge instead of just the current 100 feet.

Wednesday, May 13, 2015

Prairie Corridor Project

The final phase of a project intended to create an open corridor between two prairie areas has now been completed.  What was once a vicious tangle of invasive Autumn Olive and Multiflora Rose, now looks almost park-like.  A finish mower and a couple of picnic tables would make this a wonderful place to relax, but I have a different goal in mind.  My hopes are that this area will convert to prairie vegetation and act as a pathway to allow organisms to move freely between an existing prairie area to the upper right and a second to the upper left.  The only task left is to get rid of the few large trees.

I’ve chosen to kill the trees in place by girdling and applying herbicide.  Girdling is the act of removing a strip of living bark around the base of a tree.  This essentially stops the transfer of energy from the leaves to the roots.  Girdling alone will typically kill the top of the tree, but a forest of sprouts will emerge below the point of the cut and the tree will grow on.  To ensure the death of the entire tree, I have applied a 41% solution of glyphosate to the exposed inner bark at the lower part of the wound.  There should be no regrowth here.

The Allegheny Mound Ants that had been foraging up the tree were slightly befuddled by the loss of their path to the ground.  On some trees it took 15 minutes or more before they finally crossed the gap and went on their way.  These ants can be found on every tree in the more open areas of Blue Jay Barrens, but they do not go into the closed canopy woods.

Girdled trees included some growing in the Winged Sumac thicket.  Eventually, shade from the trees would have caused the death of the sumacs.

The dead trees should be a wonderful place for beetle larvae and woodpeckers.  Several of the trees are large enough to accommodate nesting woodpeckers.  Red-headed Woodpecker numbers have been increasing in the area over the past few years and I’m hoping that dead trees in a rather open setting might entice a pair to nest here.

Flowering Dogwood, Dwarf Sumac and a few oaks were left alive.  There are not enough of them to impede the growth of prairie vegetation.  Presence of these three species is consistent with the type of prairie typically found in this area and having them here is in keeping with the management goals of the adjoining fields.

The leafless dead trees will not block enough sunlight to slow expansion of prairie into the area.  In a few years, small limbs will begin to fall from the dead trees.  Larger limbs will follow and eventually, the trunks will come down.  Everything should be on the ground within ten years.  What happens to the fallen material will depend on how and where it falls.  Some will be left on the ground to decompose and some will be moved to facilitate future maintenance of the area.

This area to the west, just outside the trees, will be the primary source of seed for colonizing prairie plants.  Our prevailing wind is from the west and it’s that wind that carries seeds into new territories.  By the time the last tree falls, this area should be healthy prairie.