Middle Run Natural Area

All posts tagged Middle Run Natural Area

By Kristen Travers, Water Quality Monitoring Coordinator

Hiking along the new birding trail at Middle Run Natural Area it’s hard not to gaze up at the glorious fall foliage.  As the trail meanders along the tributary of
White Clay Creek, leaves from the forest canopy flutter toward the ground.  I watch one leaf as it falls into the creek and begins to float downstream.  The leaf doesn’t float far until it becomes lodged in front of a large rock along with a clump of other leaves.  Looking along the creek other clumps of partly submerged leaves, called leaf packs, are scattered. 

A leaf pack in a small stream.

I reach under the water and grab a leaf pack that looks to have been in the water for a period of time – the tree leaves are covered in a slimy biofilm of fungi and bacteria that are beginning to decompose the leaves.  Slowly pulling the leaves apart reveals a hidden habitat for aquatic insects.    A large crane fly, a common leaf pack inhabitant this time of year, wriggles out from under a leaf.

Crane fly larvae (Family Tipulidae). Photo by: R. Heringslack

These strange looking insects spend most of their life under the water as larvae using the leaf packs as both a habitat as well as a food supply. Often referred to as shredders, crane flies, along with other aquatic insects that feed on tree leaves, provide an important ecosystem function shredding leaves into smaller pieces that then become food for other aquatic invertebrates.  After living about a year under the water, the larvae pupate and change into the terrestrial adults.  Adult crane flies, commonly seen during summer months, are often mistaken for large killer mosquitoes but fortunately are harmless.  They  may feed on nectar, if anything, as adults.

A face only a mother could love? Actually this view is the end of the abdomen – the two dots are spiracles used to obtain oxygen. The head of the crane fly is small and can be pulled back into the body rather like a turtle. Photo by: R. Heringslack

The next time that you’re out hiking near a stream, look for leaf packs – scoop up a handful of leaves, the slimier the better, and see what you can discover!  Help a stream – and a crane fly – by planting native trees or shrubs in your backyard or at a DNS tree planting event.  Native tree leaves provide a better quality food supply for our local aquatic and terrestrial insects.

Prize Alert:

What is the official aquatic macroinvertebrate of Delaware?

The first person to answer correctly will win the book Delaware’s Freshwater and Brackish-Water Fishes by Maynard Raasch.  Use the “Comments” section to submit your answer (press the little number below the date at the top to comment if you don’t see a comment form).

By Derek Stoner, Conservation Project Coordinator


Rays of sunlight filter through the tree trunks in the forest at Middle Run Natural Area in Newark, Delaware. Image by Derek Stoner, June 23, 2011.

While walking through the forest at Middle Run Natural Area last night, our group from the Delaware Nature Society’s Evening Walk Series experienced several magical moments that are the good-fortune reward for spending time outdoors.

The rainstorms of late afternoon had wiped away the heat and staleness of the atmosphere, leaving a refreshingly cool and fresh air to breathe in as we hiked.  The long-hidden sun broke through the clouds and sent rays of light into the forest that looked white in the misty haze of the moisture-laden air.  Only after a rainstorm do you witness this effect, and many a movie has featured this phenomenon that adds a magic (and mystical) touch.

A Barred Owl perches in a beech tree, as the rays of late evening light filter through the woodland. Image by Derek Stoner, June 23, 2011.

As we headed down the trail I caught sight of an odd shape perched on a vine at eye-level.  Staring right at us was a Barred Owl, that blue-eyed wonder owl of the wet woodlands.  The owl allowed us to approach within twenty feet, as we made our way along the trail.  A short flight later, and the owl was now even closer to the path, almost directly overhead.  The owl looked at us calmly for a few minutes, then launched off the branch in a shower of rianwater, flying over our heads only to land again a short distance away.  The owl seemed intent on hunting, and likely had young owlets still depending upon it to supply them with food. 

A female Box Turtle laying eggs in the middle of the grassy path of the Middle Run Birding Trail. Photo by Derek Stoner, June 23, 2011.

Not expecting to find more wonder and amazement ahead, we then stumbled across anothing exciting animal: a female Box Turtle in the midst of excavating a nest!  She carefully( and slowly of course!) dug with her hind legs into the soft soil.  Soon she would deposit 3 to 6 tiny soft-shelled eggs, about the size of a nickel. We did not stay to witness this process, but wished her well as we walked out of sight…

 By Derek Stoner, Conservation Project Coordinator
The month of May is known for the bounty of beautiful songbirds that pass through on spring migration, showing off bold breeding colors and singing seductive songs.  We may only see these birds for a short time before they move on north to their nesting grounds.  You are invited to meet one of these special birds now…

A male Blackpoll Warbler perches in a Dawn Redwood at Middle Run, showing of his yellow feet and legs. Image by Derek Stoner May 19, 2011.

The Blackpoll Warbler is a small songbird that is named for its black cap (poll means “head”) . The song of the male Blackpoll Warbler is a series of several high-pitched notes that is reminiscent of a squeaky bicycle wheel. Since this warbler spends much of it time high in the canopy of evergreens (where it feeds on caterpillars), often its presence is revealed by hearing its song first.

After breeding in the boreal forest of northern Canada,  Blackpoll Warblers will then pass through the East Coast in early fall and load up on food in order to double their body weight.  In one daunting flight, they take off over the Atlantic Ocean, head south over the Caribbean Sea, and land up to 90 hours and more than 1,000 miles later in northern South America!

By Derek Stoner, Conservation Project Coordinator

A Sleepy Orange butterfly at Middle Run Natural Area, 8/23/10. Photo by Hank Davis.

As late summer rolls along, there is a great deal of movement in wildlife populations.  We often think of the songbirds starting to move south and the Monarch butterflies beginning their long voyage to Mexico, but sometimes there are strange exceptions to the “head south as fall begins” rule. 

This week at Middle Run Natural Area, our birding group made a unique discovery of an uncommon butterfly from the south.  A Sleepy Orange, a member of the sulphur family related the our familiar Clouded Sulphur, appeared along the trail and its brilliant orange upperwing  captured our attention.  Hank Davis snapped some great photos to document this unusual find.  After consulting the field guides, we all had a “life” butterfly to add to our lists.   The Sleepy Orange is only rarely seen in our region in late summer, and thus becomes a prize find for us naturalist-types.

A Hickory Horned Devil Caterpillar at Middle Run, August 23, 2010. Photo by Hank Davis.

Another interesting insect that we came across is this Hickory Horned Devil caterpillar.  Nearly four inches long  and thick as a finger, this creature with the sinister-looking antenna still has a lot of growing to do.   These guys top out at six inches long and will turn a blue-green when they reach they final instar stage of caterpillar-hood.  Hickory Horned Devils are harmless, but they sure are a monstrous caterpillar! 

If you are interested in insects, join us for the second-annual Middle Run Bio-Blitz this Saturday, August 28, from 8:00am until early afternoon.  We will search for butterflies, dragonflies, bees, and other six-legged creatures.  Join in the fun at Middle Run!  We will meet in the main parking lot off of Possum Hollow Road.