Haw-inspiring Hike

One of the reasons there are so many terms for conditions of ice is that the mariners observing it were often trapped in it, and had nothing to do except look at it.

― Alec Wilkinson

I must give credit to our friend, Bill, for the title of this post (hope he doesn’t mind). He is a poet and a wordsmith and used this phrase in an email about a hike along the Haw River we took this past Sunday with his godsons, Turner and Charlie. We hiked along the Lower Haw State Natural Area from the Hwy 64 bridge over the Haw up to our neighborhood, a distance of a little over 2 miles. Temperatures were in the 20’s when we started, but mostly sunny, and the air was still. The river, always special, was especially beautiful, with a fringe of ice along her shores that often extended far across her rocky breadth.  From the outset, the river provided visual delights and mysteries.

Mystery trails on ice

Unusual “trail” on the river ice (click photos to enlarge)

Just a short way upriver from the bridge, we started seeing some winding “trails” on the ice, looking as if someone had pulled a tiny sled in an erratic route across semi-frozen ice.

Beaver trail through ice

An open channel helped solve the mystery

Just beyond those first mysterious ice trails, we saw a partially open channel that had a similar irregular path. This one led over to an island in the river where we could see evidence of beaver chewed sticks piled along the bank. Mystery solved! The initial trails were frozen over beaver channels.

beaver chew marks

Beaver teeth marks on a sycamore log

beaver chew

There is abundant beaver sign all along the trail

From that point on, we encountered many active beaver chewed trees, some quite large. Years ago, when I was doing programs for state parks, I remember reading some facts about beavers – the largest one ever trapped weighed about 105 pounds (although my current reference on mammals says the largest on record was 86 pounds – still a huge rodent).  Average weight for an adult beaver is around 50-60 pounds. I once saw a photo of the purported record tree felled by a beaver – a tulip polar a little over 5 feet in diameter! None of the trees along the trail approached that, although the busy beavers have been gnawing on some pretty large specimens. Beavers are somewhat generalist vegetative feeders in warm months, but this time of year they feed almost exclusively on the inner bark of tree trunks and branches. Other wildlife we saw included a variety of birds – great blue herons looking for open water along the river, and a variety of songbirds trying to find something to eat along the trail. American holly berries seemed a favorite and we saw several hermit thrushes and American robins feeding in some of the large trees. Mixed feeding flocks of other species including Carolina chickadees, tufted titmice, woodpeckers (red-bellied, downy, and pileated and a yellow-bellied sapsucker), some feisty yellow-rumped warblers, and a few ruby-crowned kinglets. A beautiful red-shouldered hawk, a blue jay, and some of its cousin American crows, rounded out our bird sightings.

river rock surrounded by ice

An exposed rock in a sea of ice

As I have said before, ice fascinates me. Life as we know it depends on the unusual characteristics of water and one of these is that, unlike most other chemical compounds, when it gets cold enough to turn into a solid, the solid floats (the solids sink in most cases).

 

crystals in ice

Needles of ice in a patch along the shoreline

I remember a discussion I had about ice with a museum co-worker back in 2006.  I was lucky enough to get chosen as part of an international science and education team to spend a month in the Arctic aboard a Russian ice-breaker (no collusion, I swear). She asked me if I thought I would get bored spending a whole month out on the ice, with nothing but an expanse of white to view. I had said no, and was justified when I realized the incredible variety of forms that ice can take – all beautiful. The ice along the Haw was no different, and showed us its many faces as we gazed upon it from the bank – all magical.

beech leaf on ice

Beech leaf frozen in the surface of thick ice

ice shelf

A small ice shelf next to a riffle area

ice shelf 1

Ice lace edging along the rocky shore next to flowing water

ice waves

Intricate patterns of ice on the surface of an eddy in the river

Frozen haw

The mix of ice and open water along the river

The weather is warming, and ice is melting, but memories of a cold hike along the Haw, with good companions, will stay with us for quite some time. I spoke to our group of my appreciation for those that fought to set this corridor aside, and to the dedicated folks, like those of the Haw River Assembly, that continue to work toward its preservation. Haw-inspiring indeed.

 

Into the Haw

The rivers flow not past but through us.

~John Muir

Haw River

April is a beautiful time on the Haw (click photo to enlarge)

The Haw River flows along the boundary of the community where we live. It is a beautiful, rocky, river that flows 110 miles from its headwaters in Forsyth County, through Jordan Lake, to its confluence with the Deep River, where they combine to form the Cape Fear River. The Haw is also an important resource of recreation and drinking water for more than a million people in central North Carolina. Of course, it, and its river corridor, are also critical habitat for countless species in an area densely populated by humans. Over the years, the Haw has seen its share of pollution, from discharges from numerous textile factories a few decades ago, to runoff and nutrient overload from modern day development and other land altering practices within the river basin. The Haw River Assembly (HRA) has been educating people about, and helping to preserve, this valuable resource since its creation in 1982. I have always admired their work and diligence in standing up for the river. That is why I found myself joining a few other volunteers last Friday as we set out to do a stream monitoring assessment as part of HRA’s Haw River Watch Project.

looking upstream to bridge

Our monitoring site, just downstream from the Hwy 64 bridge

Our site is one that has been monitored off and on for several years. It is below the Hwy 64 bridge and easily accessible via a trail from the canoe access parking area.

monitoring team

The rest of our monitoring team doing chemical analyses

That is a good thing, since there is a bit of equipment to tote to your site – nitrate and phosphate test kits, petri dishes, magnifying lenses, a turbidity tube (for measuring water clarity), and a variety of nets and pans for sampling macro-invertebrates.

northern water snake juvenile

Juvenile northern water snake greeted us at our site

In addition to the water chemistry analyses, we survey the biology at our site. The primary assessment is for macro-invertebrates, which are used as indicators of water quality. But we are also take note of any other wildlife species. Shortly after we arrived, Elaine spotted a juvenile water snake sunning on a rock. Nearby was a small cloud of Eastern Tiger Swallowtails puddling for minerals along the bank of an island in the river channel.

mayfly on finger 1

Mayfly nymph pulled form underside of a rock in the river

But what we really wanted to learn was what was in the river, so most of us waded out into the water, sampling with nets as we went, and trying not to slip on the slick diatomaceous slime coating most of the boulders. This slippery surface is caused by a coating of algae and associated organic matter that coats the outside of underwater rocks and logs, especially in the slower moving portions of the river. It is an important food source for many macro-invertebrates, but can make for tricky footing for river monitors (it helps to have a long-handled net to brace yourself). I walked out a few steps and picked up a softball-sized rock in about a foot of water. Turning it over, I found two mayfly nymphs clinging to the underside. They were both very flattened, an ideal adaptation for living under rocks in swift water.

mayfly

A mayfly nymph in the family Heptageniidae

Almost any small rock that could be turned over had one or more of these flattened bugs crawling about. As any trout fisherman knows, mayflies often constitute one of the primary food sources for fish in flowing waters. They belong to a family of insects called Ephemeroptera, derived from the Greek “ephemera”, meaning short-lived, referring to the short lifespans (hours or days) of most adult mayflies. North Carolina has over 200 species of these fascinating insects. As a group, they vary a great deal in size, shape, and habit, but can be distinguished from other macro-invertebrates by the presence of three (sometimes two) tail filaments, and gills along the sides of the abdomen.

mayfly tiny

Tiny mayflies were the most common invertebrate we netted

As it turned out, mayflies were, by far, the most abundant organism we collected.And most of them were very small ones that resembled this tiny guy. I am not sure, but I think it is a member of the family Baetidae, one of the most abundant types of mayflies in North Carolina.

river rapids

Looking across the river at our sample site

Much of the river bottom is exposed rock outcrop and boulders with fast flowing water. Our most productive sampling occurred closer to shore or in areas with vegetation.

underwater vegetation

Underwater view of vegetation on a boulder in the river

I found myself going back to details I learned in classes I took years ago at Virginia Tech to try to identify (at least on a broad scale) many of the critters we uncovered. But a few things threw me and required some additional sleuthing. An early find resembled a globular egg mass on a tiny twig, but, when I discovered a more complete specimen, turned out to be a water-logged cluster of sweet gum flowers (duh). But another mystery proved to be something more worthwhile.

pupal cases on leaf

Small brown cases lined up on leaves of underwater vegetation

Some leaf fragments of some underwater plants ended up in my net and they had several small brown case-like structures adhered to them.

pupal cases on leaf close up

Closer view of cases

When I magnified the image back home, I could see white strands on one end of the case. This reminded me of the tracheal tube remains you see in a shed skin of a cicada nymph, so I assumed this was some sort of pupal case or shed skin of an aquatic critter.

blackflies on vegetation

A close up view of the underwater vegetation helped solve the mystery

When I took a closer look at the underwater image from the spot where these cases were collected, I saw a line of black flies lined up on one of the leaves. I then found some images online that suggests the cases are pupal cases of black flies.

blackfly larva

Black fly larva

A few of our samples contained some of the distinctive fly larvae. The larvae produce a silk pad and then attach to it with tiny hooks on the tip of their abdomen.

dragonfly nymph dragonhunter in hand

A huge dragonfly nymph was the catch of the day

The best catch of the day was a huge dragonfly nymph. The broad abdomen of this species is diagnostic, and probably helps hide the nymph among the underwater bark and leaf debris it calls home.

dragonfly nymph dragonhunter

Dragonhunter nymph

This is the distinctive aquatic stage of the dragonhunter, Hagenius brevistylus. Dragonhunters are the largest of the so-called clubtail dragonflies in the family Gomphidae. Adult dragonhunters, as the name implies, feed on other dragonflies and other large insects such as butterflies. The immature stage is easily recognized by the huge abdomen and “mickey mouse ears”, which are actually short, rounded antennae. The nymph is exceptionally long-lived, staying underwater for 4 or more years before emerging as a winged hunter.

dragonfly nymph

Another dragonfly nymph

In that same spot, we found another, smaller, dragonfly nymph. Something we noticed about both of our dragonfly specimens was the abundance of tiny tubes covering their body.

tubes on dragonfly nymph

Mystery tubes on dragonfly nymph

I’m not sure what they are, but they resemble the mud or silt tubes made by certain species of chironomid midge larvae. If anyone knows for sure, please drop me a note in the comment section. Our samples turned up quite a variety of macro-invertebrates, enough that the water quality index for this site was rated excellent. Below are a few more of the denizens of the Haw we found in our nets…

mayfly humped

Large mayfly nymph, possibly in the family Isonychiidae

caddisfly larva green

Caddisfly larva, family Hydropsychidae

 

hellgrammite 1

Dobsonfly larva (also called a hellgrammite)

stonefly shed

Shed skin of a stonefly nymph

isopod

Aquatic isopod

We will be sampling again in a few months and I can’t wait to see what we find. We all hope the river can maintain its beauty and diversity of life in the face of increasing pressures within the watershed. And we all owe a huge thank you to the many people and organizations (like the Haw River Assembly) that work so hard to help protect this, and the other waterways, of our state.

Hiking the Haw

A river is the most human and companionable of all inanimate things. It has a life, a character, a voice of its own, and is as full of good fellowship as a sugar maple is of sap.

~Henry Van Dyke

Haw River reflections 1

Autumn reflections along the Haw River (click photos to enlarge)

Fall color is starting to peak here in the Piedmont of North Carolina so I thought it would be a good time to hike along the nearby Haw River. The Haw is part of the Cape Fear River basin and the stretch that runs through this area is gorgeous, especially in early morning or late afternoon light. Last Friday, I got a ride down to the Hwy 64 bridge and hiked upriver a couple of miles to our neighborhood. I traveled light – the usual binoculars, a hiking pole to clear the path of spider webs, and my new Olympus Tough TG-4.

Haw River reflections

Haw River reflections

The early morning light accentuated the arboreal palette and made me wonder why I had waited so long to enjoy this beautiful hike. A few years ago, about 1000+ acres along both banks of this stretch of the Haw were acquired by the state as the Lower Haw River State Natural Area. The actual trail lies along a little over 4 miles of the east bank, from the Hwy 64 bridge to Bynum. For a couple of miles it runs along the boundary of our community, making for easy access to enjoy the sights and sounds of the river.

Haw River reflections 4

Morning sun peeking over the treetops in a reflecting pool along the Haw

The path is narrow, occasionally littered near its start by thoughtless bank fishermen, but you soon leave that and the road noise behind and are accompanied by the gurgling sounds of water over rocks.

Haw River reflections 3

The Haw has many moods, from quiet and reflective, to roaring and dangerous at high water

On this day, the river flowed gently over, and between, the many rocks that line its corridor.

Haw River reflections 2

The river level gave rise to many boulder-shrouded pools where waters were still

Evidence of recent high water is suspended in the shrubs and trees along the bank, but now I can step out into the river on the many exposed boulders that frame quiet pools. There still is enough flowing water to muffle many of the sounds of the forest along the trail, but I did hear the unmistakable chirping of a Bald Eagle at one point, before realizing it was perched in a tree right next to me. As I slowly eased toward the river bank, it flew across and perched in a large Sycamore, so I moved on, leaving it in peace. I saw a few other birds along the way, plus a lot of animal sign like Beaver chew marks and the tracks of Raccoon and White-tailed Deer. And, since it was a warm and sunny morning, there were plenty of insects and spiders out and about. A hatch of caddisflies was happening on the river, and several of these tent-winged insects landed on me as they began their aerial existence from what has been their aquatic home. I also encountered more than my share of spider webs strung across the trail (always a good sign that you are the first person to hike a trail that day). After scrambling up the bank at the main creek crossing along this section of trail (there are no bridges for the side creeks feeding into the Haw), I saw one of my favorite autumn arachnids.

Marbled Orb Weaver

Marbled Orb Weaver

Marbled Orbweavers, Araneus marmoreus, are large, brightly colored spiders, most often seen in late summer and fall. This one is a female, much larger than the males as is so often the case in the world of spiders. She was hiding in her daytime retreat, a curled leaf, off to the side of her large circular web. She pulls the leaf into a curl with silk and then hides in the safety of the retreat awaiting a signal from a struggling prey. She is able to feel their floundering via a strand of silk, a signal line, that runs from the center of the web to her hide.

Marbled Orb Weaver leaf retreat

The leaf retreat of another Marbled Orbweaver just a few feet away (look closely and you can see the spider inside)

Unfortunately, I had stumbled into her web as I climbed over a log, and pulled open her retreat. She posed for a few photos in the morning sun, and then I placed her back on the limb where some of her web remained. Just a few feet from that limb was another large web, and, sure enough, another spider hiding in a leaf retreat.

Marbled Orb Weaver 2

My spider had a glob of some sort of prey in her mouth parts that she continued to hold during the photo session

The colorful abdomens of these spiders tend to darken with age, so many appear bright orange by late October. This has given rise to another of their common names, the Halloween Spider.

Marbled Orb Weaver shadow

I caught her shadow on a branch below as she returned to her remaining web

Perhaps this species is one of the reasons spiders are often associated with this spooky holiday. Several scientists even started a spider awareness campaign on Twitter for the month of October to take advantage of this perceived connection – #Arachtober. They have some incredible photos and fascinating information about this too-often misunderstood group of invertebrates. In honor of their efforts and the important role that spiders play in our world, I will try to post a few more spider topics this week.