The Great Bat Decline: A Story of the White Nose Fungus

There’s nothing more pleasant at the conclusion of a summer day than to sit outside until dusk taking in the sights of nature, seeing the life around you change as the light grows dim and the surroundings take on a more melancholy and foreboding appearance. Such a time is perfect for contemplation of the day’s events, but also to witness the creatures of the night awaken, and realize how truly restless and robust this planet is—life is. As we turn in for the night, we hand over the baton to the next set of creatures that will continue this ceaseless relay race that isn’t set to the schedule of the sun, but rather has its outlines only nebulously bound in the depths of eternity. The hoot or screech of the owl, the mournful wails of the whip-poor-will, and the epileptic flutter of the bats in shadowy outline against the rapidly darkening sky always excited my imagination and was cause for inspiration, undoubtedly setting the stage for vivid dreams to come.

However of late, the composition of these nocturnal creatures has been swiftly changing. Though the owls and whip-poor-wills still hold in relatively the same numbers, the bats—the only mammal apart from humans that has truly mastered flight—are becoming increasingly absent from the skies, dying in the millions. Now when I sit outside at night trying to admire what I can that remains, I have to fend off vast swarms of mosquitoes, biting flies, and numerous other annoying insects that love to harass man and are no longer kept in check by those aerial predators. The time that I now devote to being outside at twilight is diminishing every year as bat numbers further plummet, insect levels spike, and my stress from both increases.

It’s hard to believe that all these interrelated problems are the result of a simple fungus— a dull and obscure one at that—but still the cause of the deadly White Nose Syndrome.

Pseudogymnoascus destructans, the white nose fungus responsible for the mass die offs, first appeared in the U.S. in upstate New York during the early months of 2006. Since then it has spread throughout the entirety of the northeast and has been detected south to Alabama. As of now it doesn’t appear to have crossed the Mississippi. While there is debate as to its origin, it appears as though the fungus was transported to the U.S. from Europe, as related bats there are also infected with it, although most seem to have built up a resistance.

The fungus receives its name from its tendency to grow on the snouts of bats, forming a small white patch that looks like a pinch of snow. It’s damaging in the fact that the pathogen rouses bats from their hibernation early, depleting their fat reserves, and ultimately causing them to starve to death.

Fungi, in many cases, can be just as detrimental as even the most virulent of viruses. Take, for example, the plight of the once ubiquitous American chestnut tree. At the start of the 20^th Century, this species was perhaps the most common tree in eastern North America, comprising a quarter of deciduous forests.  Some ancient specimens achieved truly gargantuan proportions, the trunks being nearly 10 feet thick and rising well over a hundred feet into the air. That is, until another non-native fungus was accidentally introduced into the country, also, as it happens, via New York.  Within several decades after its release into the wild, nearly every tree on the continent was eliminated—over 99% of the population felled by spores, a multitude of sizes smaller than a grain of sand. And so the same cycle has begun with our bats, and is only in the earliest of stages. Unlike viral or bacterial contagion that usually cannot survive outside its host for any significant length of time, fungi are perfectly suited to endure the harsh environment and be distributed vast distances on the wings of the wind, or perhaps, on the sole of a human boot.

The Palisades Interstate Park League of Naturalists (PIPLON) has seen firsthand how serious this decline has been. In early January members conduct an annual wildlife count within Bear Mountain and Harriman State Parks. These large and wild swaths of protected land on the western side of the Hudson Highlands, historically have been the most diverse habitat in southeastern New York, home to both rare and adrenaline inducing organisms. While still holding many unique species in its depths, every year that passes by, so too, does time drag away with it something of biological importance, leaving the land tamer and less productive.

During each wildlife count an inventory of bats is undertaken in an abandoned mine in Harriman State Park. Cranberry Mine, which actually wasn’t dug by those seeking ore deposits, was constructed in the early part of the last century to serve as a storage locale for dynamite that was being used in projects to help with park construction, such as the numerous roads that allow access to some of the more secreted lakes and other scenes of natural splendor that would otherwise be hidden from most of the public.  Burrowed into the rock, about a quarter of the way up a gently sloping mountain, the mine is hidden from a casual glance at a distance by a layer of oaks, that while aren’t overly dense, are exceedingly tall, so that the eye is drawn to them and must trace the outlines of each from the bottom to the topmost spire. It’s an ingenious cloaking device. Everything just seems to blend together and flow naturally, as water cascading down a waterfall. These ethereal looking trees, in conjunction with the rock of the mountain that bows at the base, forming an amphitheater-like enclosure, creates a wilderness cathedral. On a small knoll, a pew of this holy place, is where those of the past chose to sink their mine into the billion year old bedrock. Not until you reach the summit of this rise can you make out the entrance, which is cleverly hidden from sight by being behind the knoll and dug in perpendicular to the mountain, so that one on a head on approach to the amphitheater must shift to the left to get a full glimpse of the opening, once lined up to it.

 

Apart from it being situated to exclude discovery by accident, its perpendicular setting was probably created to provide a buffer to the nearby Seven Lakes Drive. If, for some reason, the stored dynamite was ever to detonate, instead of debris being hurled directly at the road, it would instead fly parallel to it. Older dynamite could be a highly volatile substance. Many brands of the time were essentially constituted of nitroglycerin mixed with some type of absorbent material such as diatomaceous earth or sawdust to make the product more stable. As the dynamite ages, the sticks may “sweat” and crystals of pure nitroglycerin may form on the outside. Even a minor jolt or shock to these crystals can result in a massive explosion. Today in some cases, the nitroglycerin is being substituted by more stable explosive elements for safer handling.

Cranberry Mine at its lengthiest point is around 200 feet long. At a distance of about 50-60 feet in, the mine bifurcates, each leading section then becoming much more rugged, no longer having an even floor, and the ceiling contracts, so that you now must be conscious of every move to ensure you don’t accidentally hit your head on the jagged rock above. The passage on the left-hand side is the smallest of the two in all respects, and resembles much more a natural cave than it does a man-made structure. On the floor, at the end of the tunnel, are hundreds of dried fecal pellets of the Alleghany woodrat that are at a bare minimum 30 years old. This species has been extirpated from this part of the state for many years, dying off as a result from infection by raccoon pathogens. The sole population that still resides within the state can be found in the Palisades near the New Jersey border. The only visible traces here of the bats that have succumbed to the fungus is the occasional slender wing bone, each narrower than a toothpick, more resembling fish bones than anything else. The bats which drop to the floor are quickly removed from the mine by roving scavengers, such as the aforementioned raccoons.

The longer passage to the right, once you make it past the bifurcation, quickly begins ascending, with a small rivulet running down the floor, making the trek up somewhat slippery and dangerous. The farther you penetrate into the earth, the wetter and steamier it becomes so that staying here for any length of time will result in a thorough soaking from the omnipotent drops of water plunging from the ceiling. It’s hard to imagine any bats wanting to hibernate in this portion of the mine, and yet, in a very moist segment of the ceiling we find a single little brown bat (Myotis lucifugus) clenching tightly to the rock, visibly covered in water droplets. The wings surrounding the body seem to act as a rudimentary rain coat. Perhaps this tiny bat resides here for the warmth, regardless of the dampness. It must be noted that mines provide a much more equable environment than in the open and capricious air outside. Year round the temperatures remain about the same. In the winter it stays well above freezing, while in summer provides refreshing relief from the oft-times overbearing heat.

Scattered in various clusters throughout the entirety of the mine we discover isolated pockets of the big brown bat (Eptesicus fuscus). In certain nooks there are 2 or perhaps 3 bats nestled together, grouped so closely it’s difficult to determine where one ends and another begins. It’s simple to see how the fungus spreads easily with the bats so compacted. The occasional loner is also present, unable to find a compatriot in this roomy cavern. Prior to the fungus’ entry here, every survey turned up hundreds of individuals comprising several species. On this January day 7 big brown bats and a single little brown bat were recorded, giving us a grand total of 2 species and a mere 8 individuals. This precipitous decline is depressing to witness as you walk around where there were once a multitude of slumbering mammals overhead forming furry, brown blankets— now all you see is the cold, damp, and dismal rock, with the addition of the occasional cave cricket hiding in the crevices of the lower ledges, adding to the sense of loneliness and desolation.

This is just one cave of many that has experienced the punch that the white nose fungus delivers indiscriminately.

To help lessen the spread to the few locales not yet contaminated, it’s important to stay out of sites that bats like to frequent, such as their favored caves and mines. As mentioned earlier the spores of the fungus can easily hitch a ride on clothing and shoes. While bat numbers will undoubtedly continue to fall for quite some time and certain previously rare species may unfortunately pass into the history pages, unable to recoup their losses, it is hoped that like their European counterparts, many will develop a resistance to the fungus and make a rebound. We haven’t lost them entirely just yet.

The Original A.T. Shelters

Approximately 12,000 years ago as the last of the glaciers made their final retreat northward as the weather warmed, causing them to rapidly melt, the ancestors of the Lenape tribe made their way into the land that now comprises New Jersey, New York, and parts of Pennsylvania and Connecticut. The first landscape was a barren tundra, resembling those now found in the northern reaches of Canada and Alaska. Caribou, mastodon, and even the occasional mammoth roamed the land, serving as prey for the newly arrived people. Few trees existed. Large boulders strewn across the landscape, known as glacial erratics, and overhanging rock ledges on the sides of mountains were all that existed to shelter the Lenape from the frigid, arctic-like weather. As the climate improved over the millenia, tundra gave way to spruce and birch forests, and from there, to a forest similar to the one we know today comprised of oaks, hickories, maples, and other well known species.

The bare and gray background developed into a lush, forested landscape. Trees towered over the once all important “rockshelters.” Though wigwams and longhouses were now being constructed from the ubiquitous vegetation, these simple, craggy structures were still being utilized by Native Americans. A lone hunter deep in the woods tracking his quarry for miles might spend a night beneath an overhang afforded by a massive boulder to avoid the wind of a cool fall night or perhaps to escape the drenching rain of a summer thunderstorm. Additionally, these places were also frequented by larger groups as they migrated. These people moved seasonally from site to site to be in a better position to collect newly ripening plants or to make it to a certain spot in time to find arriving game animals or spawning fish. They might move to a grove of mast producing species to collect the nuts of oaks, hickories, or chestnuts, of which they were especially fond. And in the spring they might traverse the land to encamp near a stream or tributary of the Delaware or Hudson River to trap the herring that swim up them to spawn. Their lives were variable and subject to the capricious whims of the environment, but the rockshelters were the one solid constant that could always be relied upon when they needed protection from the elements.

Many of these once occupied rockshelters can still be seen along portions of the A.T. today, even in some of the highest and most seemingly inaccessible locations. As such, thru-hikers and Natives of the past seem to share a few similarities. Apart from visiting these remote spots, both have known the pain of lugging a tremendous amount of weight around for lengthy distances—the hiker, a 30 pound pack on his back; a Lenape native, a recently shot deer carcass that had to be dragged back to camp, or maybe a pack-like bundle that contained the camp itself and needed transportation to a seasonal locale that could only be accessed by crossing over a steep mountain range or two.  Each has also witnessed the beauty of the forest, of nature itself, and has reverenced the mysteries that are contained within. Though separated by centuries they share a common uniting force—the rocky land of the Appalachians.

Every day a hiker makes his way through the Mid-Atlantic States he passes by a multitude of sites used by the Lenape, although few recognize them.  Many see stone, but nothing more. The cultural aspects of the land are just as important as its ecology or natural history.

 Many rockshelters appear as though they would be the perfect spot to encamp; others are smaller or more covert and their tales are only told by the archaeological record. The occasional open air campsite can also be found on flat terraces near streams and lakes, as are larger village sites.

Right around the creation of the Appalachian Trail in the 1920’s, archaeologists began seriously investigating the land that exists within the bounds of Harriman and Bear Mountain State Parks in New York. It was a boon time for excavations and for the documentation of new sites. Many of the artifacts pulled from these digs made their way into the historical museum at Trailside Museums and Zoo, located directly adjacent to the Bear Mountain Bridge. Trailside was envisioned by Benton MacKaye, who wanted a nature center such as this placed at regular intervals along the A.T. This is the only one that actually came into being, unfortunately.

Apart from the remains of Fort Clinton from the Revolutionary War, there are numerous archaeological sites located within Trailside relating to Native Americans.  The largest is an open air campsite overlooking the Hudson River atop an airy bluff. This is the lowest spot along the entire A.T., at only 120 feet above sea level. The site is directly opposite the bear den and is identified by a small sign that briefly discusses the history. Follow the “Geology Trail” east and you will pass though part of the campsite that is bounded by a small stream on the left. A sunny promontory at the trail’s end was probably used by the Natives to fashion stone tools via a process known as flint knapping.  Recent invasive species removal has restored the site to its former glory and probably closely matches what it would have looked like several millennia ago when the first Indians occupied it.

Over the years, 4 or 5 excavations have taken place near the bear den campsite, the most recent being in the fall of 2013. A water pipe that is buried through part of the campsite needed repairs, and as such, the surrounding area had to be dug up. A 6x3x3 foot plot uncovered 2 chert knife tips, 2 hammerstones, various chert and jasper cobbles, and slightly over 100 stone waste flakes, known as debitage. This rich spread of artifacts in such a small area is somewhat unusual, especially considering that previous excavations have been done here in the past. However, in the early days of Trailside’s history archaeologists on staff were mostly concerned with preserving museum quality specimens (usually arrowheads) that were coming out of the ground and paid little attention to the raw material or tools required to make them. Contemporary archaeologists now tend to focus just as much of their attention on the seemingly most insignificant of artifacts as they do on the most prestigious and well-made. They realize that much can still be learned from broken artifacts and purposely discarded waste pieces.

Despite what many people might think, Native Americans, in most cases, actually ate quite well. We can tell this was true by examining the bones, shells, and to a lesser extent, carbonized remains of organic material left behind in rockshelters. Due to the acidic nature of northeastern soil, many faunal remains will not generally survive more than a few centuries. If sequestered within a rockshelter these artifacts may remain in better shape and survive longer than they would in an open air campsite.  A majority of surviving organic items pulled from these structures in New Jersey and southern New York date back to the Late Woodland period (1,000-400 years ago). These people consumed a wide array of animals, many of which are now extinct or extirpated from the region, such as passenger pigeons, Alleghany woodrats, mountain lions, and even bison (their historical range extended to the western side of the Hudson River). They further supplemented their diet with deer, turkey, beaver, bear, and shellfish that used to exist in copious quantities in the upper reaches of the Hudson and Delaware Rivers that routinely were as large as an outstretched hand. The Natives certainly appear to have eaten better than some hikers do today.

Next time you’re on the trail I would definitely recommend taking a few minutes to examine a rockshelter or two, especially the larger ones. It’s no secret that the NYNJ Trail Conference purposely routes numerous trails so that they pass by the most interesting rock formations.  Usually a shelter is among them.  While many look shabby today and are infested with myriads of insects and have a dense leaf strewn floor, in prehistoric times, if these sites were used for more than a few days at a time, the appearance would be significantly different.

Let’s say for example, two people, a man and a woman, are occupying a shelter for several days 1,000 years ago. If we were to look inside we would find that the ground is swept of leaves and a fur garment is covering the dirt floor to ensure a warm and congenial feel; the man is just outside butchering an animal. When his task is complete he hands a clump of meat over to the woman who promptly begins cooking it over the fire that’s constructed under the rock eave. By her side in the rockshelter, sitting on the ground, stands a couple small, decorated clay pots filled with water collected from a nearby stream that will be utilized for a variety of tasks. When night settles in the two move closer to the fire for added warmth and light. As they lightly converse the man does some minor tool repair. Shortly after he finishes up, the two fall asleep wrapped in blankets of thick deer and bear hides. The fire slowly wanes and all is enveloped in darkness, with only the occasional yelp of a coyote sounding in the distance.

 You have to look past the dreary mess in the shelters today and imagine how it once was.

The Cats Rock Rockshelter in Pawling, NY would have fitted a pair of Natives comfortably like the ones just described. This very large glacial erratic, on par with the size of a small house, is situated on a steep mountain slope just north of the Telephone Pioneer lean-to.  Its ample overhang would have ensured great comfort, and ease when walking around.

These sites are fragile so it’s best to tread lightly. There’s nothing worse than to see an archeological site contaminated with modern debris—it really does diminish the ambiance of it. While this shelter is a prime example of what Natives would seek out for a night’s rest, this particular site is moderately degraded by the buildup of trash and through use by rock climbers.

The Lenape viewed this world differently than most of us now see it. Everything, living and non-living, was imbibed with a spirit, even the cold and prosaic rock beneath our feet. Mankind was but a single puzzle piece to this world. All deserved respect. The last remaining Lenape today hold the rockshelters and other sites utilized by their ancestors to be sacred.

When it comes to sacred sites, some were revered more highly than others. Waterfalls were especially meaningful to the Lenape and many would travel far out of their way to reach one to pray or conduct ceremonies. The same could be said with certain overlooks atop hills or mountains that afforded sweeping views of the landscape that kindled their connection to the divine.  Every bit of the land was precious, but especially the stone, which they used for shelter, made tools out of, along with stone bowls and ceramic pots, not to mention use as a canvas—the occasional petroglyph can be found etched into bedrock outcroppings. Though they no longer frequent the rockshelters or tread the valleys and peaks of the Appalachians, the land is still looked after and maintained by like minded beings—A.T. hikers that see there is more to the land than just the value of natural resources it contains.


Michael Adamovic is an avid A.T. hiker and serves as a site steward at several state parks in southern New York as part of the Native American Site Steward Program (NASSP). He holds a Bachelor's degree in Environmental Studies from Manhattanville College.

This article will be appearing in the July 2014 issue of A.T. Journeys.

The Phragmites Invasion

Almost no matter where walk today, be it either in our yards or in a seemingly pristine state or national park, we are always constantly in the presence of invasive plant species. There is no escaping them. It’s like perpetually living in a horror movie. You spot one, try to get away by moving in the opposite direction, but no matter where or how fast you run, as soon as you turn round a bend, another one pops up, and then another, and continues this way for 3,000 miles from the east coast to the west coast. They’re as ubiquitous as the leaves on the trees. It’s quite intimidating, actually.

Despite their prevalence, many times they will go unnoticed, or if we can identify them and are aware of negative changes they deliver to an environment, we are apathetic due to their beauty, as is the case with many ornamental plants. One species that isn’t often praised for its beauty, is painfully widespread, and devours an ecosystem as readily as a swarm of locusts is a common and in a physical sense, dull reed. Phragmites australis, which undoubtedly everyone has seen at one point or another, is one of the most damaging threats to wetland and aquatic habitats today. They push out nearly all native species, both plant and animal, forming a dense and nearly impenetrable wall 10-15 feet in height that usually is measured in acres.

 

Where marshes or swamps were once relatively open and contained clumps of cattails, tufts of sedges just barely poking above the water that could be utilized to traverse the wetland by using them as a set of stepping stones, the occasional tree dotted here and there, and a rich array of wildflowers in all colors from the bright blue of the plebian forget-me-not to the scarlet grandeur of the aptly named cardinal flower, now in many cases these spots have been become so dense nearly everything has been eliminated. Biodiversity is wiped out and replaced by a monoculture of phragmites. Wetland species that were once rare before the invasion are declining at alarming rates as the reed continues to take a bite out of healthy habitats. The golden-winged warbler is one such species whose numbers have plummeted as a result of habitat alteration.

This reed with its prodigious biomass creation also has a tendency to rapidly fill in the areas which they inhabit. Small ponds can completely disappear and the total area of a wetland will shrink upon being colonized. After a stand has been cut down, and one walks out into the where the infestation once stood, there’s a spring to your step as you navigate a floating mat or island of dead phragmites several feet thick that has built up over the years. It’s no wonder that people of the past used reeds like these to construct rafts and thatch roofs.

It’s interesting to note that this invasive has been here for an incredibly long time (at least centuries), but no one can pinpoint exactly when or how it made it over here. It’s generally believed to be of Eurasian origin. Over the past few decades, for partially unknown reasons, the reed has been speeding up its hostile takeover.

There is also a native variety of phragmites, although its numbers have been diminishing as it is being replaced by its more aggressive cousin. Native phragmites typically is sparser and will not form stands as large as the non-native Phragmites australis.

Sites within the Hudson Valley have especially felt the effects of the invasive, having a large tidal estuary in the geographic center that is fed by many small, marshy tributaries—all prime habitat for phragmites. The Palisades Interstate Park Commission which manages large tracts of land in the region is beginning to fight back and has already begun implementing plans to remove the reed from already pre-established infestations, and perhaps more importantly, to slow its spread to other areas.

The most current project is being undertaken in the sensitive marshes of Iona Island, a part of Bear Mountain State Park in the Hudson Highlands. A couple notable species that call the mudflats home are the threatened saltmarsh aster, which has the largest population in New York at this location, and Needham’s Skimmer, a rare dragonfly that can only be found in a handful of brackish tidal marshes in the state. These species which almost entirely rely on this type of habitat feel the full force of the phragmites encroachment and are highly susceptible, as much of their preferred habitat has already been destroyed by development. Without a plan for remediation, possible extirpation is possible. For these reasons primarily, the marshes of Iona Island were the perfect candidate for remediation.

Over the years, various methods have been employed here but haven’t been especially successful. One of the most comical techniques employed has utilized a type of human “hamster wheel” to roll over and break the stalks. Machete hacking has also been used, but is an incredibly slow process that only offers a seasonal solution. Unless the roots are destroyed the plant will pop back up in full force the following spring.

In the late summer of 2013, the Park Commission turned to the use of herbicides to finally ensure a quick and complete eradication of phragmites. Using a tank-like, amphibious vehicle to gain access to the mucky environs, sprayers atop the vehicle went back and forth in long rows applying herbicide to the reeds, ultimately covering nearly 40 acres. Upon the death of the invasive the desiccated stalks have to be cut, bundled up, and removed.

Herbicide is only used as a last resort as it has the possibly to upset the delicate balance of the ecosystem. After a lengthy review process it was determined that this was the best route to protect the marsh’s biodiversity and prevent it from wholly succumbing to the influences of phragmites as the other methods weren’t working as hoped. The herbicide’s effectiveness is undeniable, however.

It is the goal of the Park Commission to each year spray a similarly sized patch, until ultimately the entire nearly 200 acre marsh has been covered. Spraying it in sections ensures the ecosystem has time to heal itself and will not undergo “shock” from a larger and more comprehensive treatment.

Another technique that may be tried in 2014 is to flood portions of the marsh by installing small flood gates on an outlet attached to a road that leads to island and bisects the marsh. A water level rise of only a few feet should be sufficient to drown the roots by keeping them perpetually submerged even at low tide.

West of the Hudson River, in the secluded interior of the Ramapo Mountains lies Sterling Forest State Park where phragmites is also a serious issue. At several scattered wetlands here the same herbicide measures are being undertaken to rid the reed. Sterling Forest is one of only a few places in southern New York that still has relatively abundant populations of the golden-winged warbler. Over the past decade numbers have been dwindling across the country and it may be designated as a “threatened” species in the near future if the trend continues.  Estimates have put the decline at around 7% annually.

These birds utilize wetlands and nearby forests for nesting sites. Surveys have shown that areas invaded by phragmites have little to no breeding pairs. Golden-winged warblers prefer sparser, natural vegetation, as do many other bird species.

The park is also home to the endangered northern cricket frog. While these frogs are confined mainly to one lake in the park, and surveys of many of the treated wetlands have not been able to document their presence, it is still possible that small remnant populations remain or that the creatures may return in the future.

Apart from the negative impacts phragmites dishes out, it does offer certain benefits. The reed’s expansive root system is helpful for controlling erosion and in low lying coastal areas the tightly packed stalks can help lessen the blow of storm surges. Furthermore, the red-winged blackbird is one of only a few species that actually thrives in the reed’s presence and utilizes the plants for nesting. It would be a grave error to stop eradicating phragmites for these few benefits, however. The negative side significantly outweighs the good. Protecting biodiversity and ensuring that ecosystems remain as natural as possible should be our number one goal.  Phragmites control gives other species, especially those that are rare, a chance of survival.

A Problem that Grows a Mile-a-Minute

Forest ecosystems from North Carolina to northern New England and west to Ohio are under siege from a knotty invasive vine that darts from the ground to the canopy at lightning speed. Mile-a-minute  (Persicaria perfoliata), a native to China and Japan, can grow up to 30 feet in a single year and produces hundreds of seeds that have the capability to survive in the soil for up to 7 years. The fact that the seeds resemble plump blueberries makes them a tempting treat to wildlife. Deer and birds are efficient dispersers. Vines readily climb trees and other vegetation to form dense clumps that easily smother native species. This tyrannical engulfment has garnered the plant the name “Kudzu of the North.”

Just above New York City in the Hudson Valley, numerous state parks have seen native biodiversity nose-dive since the arrival of the plant here about a decade ago. The only thing that has appeared to increase is the number of invasive species that now call these city retreats home.  It’s a serious issue that the Mile-a-Minute Project of the Hudson Valley of recent years has been attempting to mitigate. After finding hand-pulls hopelessly ineffective, in 2009 the staff turned to looking into using a newly tested biocontrol agent that was deemed safe by the University of Delaware. By releasing thousands of tiny weevils (Rhinoncomimus latipes), no bigger than the size of a pin head at the infestations, it was hoped these insects would significantly diminish the plant’s fecundity. R. latipes shares the vine’s native range in Asia and feeds exclusively on the plant, making it a prime biocontrol agent.

 

 

Once a year since 2009, the Mile-a-Minute Project has done releases on parkland with severe infestations. Around 15,000 weevils have been released at 9 sites since the program’s inception. Each location is monitored once a month from spring to autumn. Inundating the sites only once with large quantities of weevils has proven to be the most effective, over smaller, continual releases.

Apart from the weevils slowing the spread of the vine to new locales through a reduction in seed production, the biocontrol sites themselves generally show a 10% decrease in mile-a-minute the year following the release. Progress is slow, but steady. 

The advantages of biocontrol over manual removal are significant: the weevils are self-perpetuating; they can travel a distance of 10-15 miles a year on their own; and can reach areas inaccessible to human eradicators. Additionally, these insects are cheap to obtain and save large quantities of time that would ordinarily have to be devoted to pulling the plants or by spraying them with herbicide.

When new regional infestations are investigated normally around 75% are found to contain hungry R. latipes munching on the plants. With the range of invasives rapidly expanding and new species getting introduced to the U.S. every year, biocontrol is quickly becoming the optimal measure to deal with these invaders.

Related links:
http://www.lohud.com/article/20130913/NEWS/309130041/Goats-beetles-join-local-fight-against-invasive-species?odyssey=mod%7Cnewswell%7Ctext%7CNews%7Cp

http://www.lohud.com/apps/pbcs.dll/gallery?Site=BH&Date=20130913&Category=NEWS&ArtNo=309130067&Ref=PH

http://www.mville.edu/news-a-events/news/manhattanville-in-the-news/4661-manhattanville-college-alumnus-recognized-for-his-work-with-invasive-species.html

https://www.facebook.com/#!/MileAMinuteProjectOfTheHudsonValley

 

 

Northern Cricket Frog

Beginning in mid-May and lasting up until the end of July anyone hiking the Trail near streams or lakes from Georgia  to the southern boundary of New England may be rewarded with hearing one of the smallest and probably least well known amphibians in the eastern portion of the country—the Northern Cricket Frog (Acris crepitans). Although, most individuals who have the unique call fall upon their ears probably misidentify it as its namesake. Cricket frogs really do not sound like frogs at all. Their calls more resemble a low pitched cricket in both sound and duration. The best description that can be rendered as to what they sound like has been described as two pebbles being clicked together, and in a manner that is similar to an insect chorus. Furthermore, their diminutive size also lends itself to the aptness of the name. This species will rarely exceed one inch in length. Their appearance is also highly variable and two individuals found in the same location may superficially resemble separate species. Body coloration ranges from almost completely black to light brown or green, and many will possess vibrant stripes of red or green dorsally. Males during the mating season will also frequently be found with yellow patches on the throat. In short, they are the hidden gems of shallow watery environs.

Northern cricket frogs can be found in relatively stable numbers in the southern states, but in an ironic twist, they are actually becoming quite rare in the northern portion of their range and in many states have been placed on the threatened or endangered species list. The causes for this are many, but in some cases it is still a bit of a mystery as to their rapid decline, as no noticeable physical problems or habitat change can be seen in certain locations. Most cricket frogs are very short lived and have an average life expectancy of approximately 4-8 months. Some have been known to survive for up to 5 years, but this seems to be a rarity in the wild. Having such a short lifespan can be problematic as even a short term disturbance to their habitat can wipe them out from an area permanently. Pollution, habitat destruction/alteration, and parasites are the most well known causes for dropping numbers. They are highly susceptible to even minor environmental changes and are known as indicator species because of their lack of tolerance to disturbance and can therefore indicate when a habitat is first starting to cross the threshold to becoming polluted or being degraded by other means.

In New York, their numbers are plummeting, and the few populations that still exist here are in danger of being extirpated from the state within a short period of time. Researchers do not believe the frogs are under fire from the chytrid fungus, which is infecting some individuals in the Southeast and is responsible for killing off droves of other amphibian species worldwide and even leading to extinctions. Habitat destruction plays a small role at best, as most of the lakes these frogs reside at are on protected land. Pollution may be a large factor, but is most likely not the primary cause, as other frog species at these locales are thriving. Whatever the cause, biologists are rapidly seeking solutions to improve conditions for the frogs until hopefully a concrete identification can be rendered for the reason behind the die offs. It’s depressing to note that within the last century 20 of the most significant sites within the state have been lost. Most losses have occurred within the past few decades.

In Sterling Forest the AT passes along the northwest bank of one of the only lakes that still has a large reproducing population in the state. Over the previous summer the Environmental Bureau of NYS Parks teamed up with volunteers to aid in a habitat restoration project at this particular lake. The cricket frog does well in water bodies that are relatively shallow and contain numerous aquatic weeds along the periphery. Previous to the work completed, the banks of the lake were very steep and rocky. The main priority was to extend the banks slightly into the water and give them a more gradual slope so the frogs would have no difficulty coming ashore. Peat moss was also thrown down to fill in the gaps created by large rocks near the shoreline and render the area more hospitable to plant life. As these creatures hibernate during the winter months, the added peat will also serve a dual purpose by providing much needed insulation. Cricket frogs, unlike some other species, are freeze intolerant and are highly susceptible to the cold and must burrow into the earth to avoid it. Invasive plants, such as purple loosestrife, a species that is choking off native plants, was also removed. Officials are hopeful that these improvements can at least marginally stabilize the cricket frog numbers and ensure the state does not completely lose the species in the near future.

Despite the dreary outlook for the cricket frogs there still is cause for hope. Solutions are being actively sought after by researchers to save this species in the north, and volunteer interest is helping to drive both habitat protection and bring increased awareness to this largely unknown matter. It is delightful to hear a northern cricket frog chirp on a warm summer day after completing a long day’s hike. To me, the calls are more pleasant than even the sweetest bird song—it would be a shame to lose them forever and have to sit on a bank to hear only silence.

This article has previously appeared in the May-June issue of A.T. Journeys.

Vicious Vegetation: Invasive Plants-- the Negative Nuances of Forceful Flora and Belligerent Blossoms

In the past our forests fell solely by the ax of the lumberman—a quick and clean end that had some utility. Today, the destruction is brought about by a far more insidious foe that slowly sickens and displaces once robust and diverse native plant life with alien invaders that usurp our native variety. Invasive species, while typically unassuming individually, given time and the chance to propagate, can bring about more change to ecosystems unconsciously than we can do with even the most ambitious plan. Apart from the harm invasives cause to native habitats, to hikers and trail maintainers, they pose an incredible nuisance by forming dense and impenetrable thickets that not only cause physical harm and annoyance, but are responsible for the destruction of equipment and the engulfment of trail and shelter land. You don’t have to be an ecologist to see the damage invasives inflict.

While many of us have heard the term “invasive” used before and have a general idea of the subject, what exactly constitutes an invasive species?

An invasive plant is one that that was never present in an ecosystem prior to its transport by human aid; typically has a high tolerance range to a wide variety of habitats; can thrive in adverse environmental conditions, such as hostile weather and low quality or contaminated soil; and finally, possesses an extremely high fecundity, where the plants are capable of producing vast amounts of offspring year after year. Not all non-native plants are invasives, and not all invasives are from some far away continent—even plants from North America transported to somewhere out of its normal range (perhaps only a few hundred miles) have the capability of developing invasive qualities. Native species, many of which do not have such weedy traits and have no means to resist the invaders, are generally outcompeted and displaced.

A majority of these detrimental plants were brought to this country for use as ornamentals. Many continue to be bought and planted despite the well known invasiveness they pose if they escape cultivation. We further lend a hand whenever we degrade the land. Environmental disturbance and invasives are synonymous.

Some of the major offenders along the Appalachian Trail need no introduction. Kudzu in the Southern states is one such example. It’s so widespread and its damage is so familiar it doesn’t even warrant a description here. Other species that rival it in forest alteration but remain in the shadows, both literally and figuratively, should be brought to light.

Major Offenders

Japanese Barberry

Japanese barberry is one of the largest nuisances to hikers. Being a small shrub that averages about waist high, its thorny branches often lead to painful scrapes and where present in dense quantities can lead to higher rates of Lyme disease. Recent research has shown that ticks thrive in the shady and damp confines of the bushes.

In addition to human impacts, the leaves can alter soil chemistry, and due to how thick the shrub grows, will often exclude native species from the understory. Its bright red berries that are produced in the fall are a tempting treat to wildlife. Birds and deer rapidly disperse the seeds.

This species is one of the most popular invasive ornamentals still planted, much to the consternation of ecologists. It is worryingly easy to buy. Visit any nursery and it is likely to be found there.

Even state officials can be ignorant. Decades ago, not long after the creation of Bear Mountain State Park in New York, barberry was planted along several trails to keep visitors from wandering off them. Today, barberry is rampant throughout the park and can be found in prodigious amounts all along the Appalachian Trail as a result. Though it is now being removed, mostly through the efforts of the NY-NJ Trail Conference and volunteers, it is now so prevalent it will remain a permanent staple of our forests. Cutting the stems is only a seasonal solution—in the spring they will resprout. The only effective removal method is to dig up the roots, a strenuous and slow process. Prevention is the best cure.

Multiflora Rose

Another invasive similar to Japanese barberry is multiflora rose, although everything about it is of a larger magnitude. It can easily form clumps as long as a car and tower well above head height. Its thorns are formidable and pierce the flesh like needles. They are often referred to as “fish hooks.” Its modest white blossoms hardly warrant an excuse to plant this bush with all the inconvenience that comes along with it. Each bush can produce up to a million seeds annually that have the capability of surviving buried in the soil for 20 years.

 

 Swallow-wort (Black and Pale)

Based on its nickname of dog-strangling vine, swallow-wort is a species that is not to be underestimated.  This plant favors forest gaps and other openings that allow ample light to penetrate to the forest floor. In optimal conditions, swallow-wort can become so dense that walking through a patch proves challenging, as the vines are tough enough to resist being broken or uprooted and can easily trip a person, or seriously ensnare wildlife as the nickname suggests. In early autumn its seed pods, similar in appearance to those of milkweed, open up and cotton-like seeds are dispersed by the wind as easily as those of a dandelion.

Apart from manual removal, biocontrol agents are now being researched for use. Having the ability to use another species to control an invasive is often a much better option than by utilizing human labor. Biocontrol agents travel long distances on their own, can access sites we cannot, and are self-perpetuating, so that once released they will remain in the wild indefinitely, or until the food supply runs out.  It’s essentially having an army at your disposal that costs almost nothing.

Each biocontrol agent goes through a rigorous and lengthy research and review process. Before releasing a life-form into the wild, which is usually also of non-native origin, it must be made clear that the organism will only attack what we want it to. It would be incredibly counter-productive if what was released somehow itself became an invasive.

At the moment a noctuid defoliating moth (Abrostola clarissa) from Eurasia is being quarantined and tested at a site in the U.S. to see how effective and safe it will be to have it devour  swallow-wort at selected locations. It will be years until it is utilized if deemed entirely host-specific to swallow-wort.

Several other invasives are already being dealt with using different forms of biocontrol. Purple loosestrife and the nascent mile-a-minute vine are two species which are being successfully controlled also through the use of insects.

                                                                      Japanese Stilt Grass

Hikers are highly likely to spot Japanese stilt grass at shelter sites and along sunny reaches of the trail. When rolling fields or glades near the shelters are filled with nothing but stilt grass—which is quite often—it appears as though the site is cast adrift on a sea of green. While marginally stunning, the detritus left behind after the plants die off will result in an increased alkalinity of the soil and alter the nutrient availability. Grazing by wildlife, a natural control method, is by-passed by uninterested wildlife, enabling it to spread unchecked. The plant’s high stature and denseness is the perfect habitat for rodents, namely rats to infest. An increase in rodents close to human habitation is always worrisome, as the risk for disease rises in step with the pest’s abundance. Stilt grass is remarkably easy to pull by hand, but its prodigious populations make removing it an overwhelming and tedious task.

 

 

Forest Forensics

Quite often, being able to recognize certain combinations of invasives can lead to a past reconstruction of what an area once looked like. For example, many places in New England where the trail now passes through was formerly farmland. It may be hard to believe, but there is more forest today then there was a hundred years ago in the eastern half of the country. This is due to a change in agricultural preferences, where farmers understandably relish the flat, rich plains west of the Mississippi, over the stony and glaciated Northeast. Today, we hike through many abandoned fields that have once more reverted to a more natural state and apart from an occasional stone wall, leave seemingly nothing open to the imagination.  In the absence of fences, walls, and crumbling foundations, we can tell an area was once a planting field or pasture due to the presence of several invasives.  Finding Japanese barberry, multiflora rose, and black locust trees all present in the same general location can lead you to surmise that in the not so long ago past this patch of forest probably once supported someone’s family. Being able to indentify invasives and understand what they mean grouped together can be very rewarding.

Many invasives that we now encounter near the trail are present in extremely large quantities due to forest succession. After a vacant plot of land is abandoned it naturally begins reverting to forest. First, the herb layer sprouts, and is filled with native tall grasses, asters and goldenrods, and now without a doubt, invasives, possibly ranging from swallow-wort to thistle. A year or two after the field is left fallow the shrub layer emerges. Japanese barberry and multiflora rose predominate. Next, the trees make an appearance. The first native colonizers generally consist of tulip poplar, red maple, and black birch, among others. But in addition to the natives, we also have the foreigners like black locust trees that farmers used to mark their property boundaries with and now this tree sprouts as readily as the crops the farmers once planted. The Asian Tree-of-Heaven and the Norway Maple also have a hard time resisting the prime real estate that has just opened up.

Adding more forest to our fragmented landscape is overall beneficial, but with all positive things, something bad usually tags along. With all the invasives now released into this country, natives are at a disadvantage when it comes to repopulating vacant land, and the forests that emerge are usually of a lesser quality in terms of appearance and biodiversity. As the forests mature, the natives do generally gain slight advantages and the non-natives’ presence will deteriorate—but not completely.

This article has previously appeared in the September-October issue of A.T. Journeys.

 

 

Autumn in the Hudson Valley: Part 2 (Foliage)

The first tree species to begin the color change is the red maple (Acer rubrum).  It progresses from a glaucous green to a deep and vivacious scarlet. Often in mid-August in watery or swampy environs the transformation has already begun. Water is key to the premature reddening, without which, trees may not be imbibed with their autumnal hues for another month or more. It is not entirely understood why this occurs.

The red maple is a highly adaptable species, and is one of only a very select few that can successfully colonize the three main environmental realms: hydric (swamps, river or stream edges, and other water-laden locales), mesic (upland locations with rich, thick, and well drained soil), and xeric (dry, hot, and rocky with a thin and/or poor soil base, often found on high hills or mountains, especially on southern facing slopes).

Usually the next tree to change is the sugar maple, which garners a vibrant, highlighter-like orange. This upland species is often found mixed in a typical forest environment, and is often located in residential areas where it is commonly planted as an ornamental or for the sweet sap that can be collected in the spring. Before other trees of the neighborhood have even a hint other than a summer green, the sugar maples develop orange patches. It is usual to see one side of a tree completely morph before the other begins, and it can be several weeks before the entire tree is a solid shade of pumpkin.

After the sugar maple, many other species gain the colors of autumn simultaneously and it is difficult to predict which order they will follow. For this reason, I will describe the various tree/shrub species that inhabit our area from red to violet, or in the order of the color spectrum. To my knowledge, no tree or shrub species has a blue or indigo related tint, and as such, these shall be omitted from the list.

Apart from the red maple, tupelo, or the black gum tree, possesses the most stunning dark red, or crimson foliage of the forest. Each falling leaf is a drop of blood. When the limbs are bare, the ground beneath looks as if some terrible massacre has unfolded there, leaving no survivors of either party. Even when dried, and other species would have lost most of their coloration, it is remarkably well preserved in those of the tupelo.

 

While blueberry bushes have the distinction of producing the only edible fruit in the country that has a true blue coloration, in the fall its leaves also turn blood red, giving the impression of a burning bush. The Shawangunk Ridge, being the extreme western border of the Hudson Valley, is legendary for producing vast scarlet fields in mid-October. Sam’s Point Preserve, along with Minnewaska State Park, are two prime locales to view this undulating sea of red. There are probably no better spots in the state to witness this epic transformation.

The brightest and most well known color of the fall belongs to the orange sugar maple. It has become a widespread staple of the season, better than probably any other species.

A smaller, thinner tree in the orange spectrum that usually receives less attention than its proliferic maple cousin, yet has hues just as dazzling is that of sassafras. This species primarily resides within the mid to upper levels of the understory and has leaves which quite distinctly resemble dinosaur footprints. Each leaf usually has 3 deeply curved lobes that make it look as if it’s trifoliate, similarly to a clover; although sometimes they are of a slightly different morph and more closely resemble mittens, having one large lobe attached to a smaller one that is both sharper and pointier at the tip, the thumb of the leaf as it were.

While frequently exhibiting an orange coloration, slightly darker than sugar maples, sassafras also shows significant variability in its color display. At times, every leaf on the tree can be a dandelion yellow or perhaps scarlet, with red-orange undertones intermixed.  It’s important to note that every tree, like that of a person, has a different “personality” and like a mood ring, displays each of its emotions in a separate color, based on the level of its stress and rapidity of biochemical degradation within the leaves that ultimately determines color.

Sassafras roots were once used as a main ingredient of root beer and sassafras tea until being phased out by the FDA in 1960 once safrole, an oil produced by the tree, was found to be mildly carcinogenic and damaging to the liver. The ban on sassafras tea expired in 1994. It is now believed that a can of alcoholic beer poses a greater carcinogenic risk than that of a cup of tea.

Early on in the 17^th century, sassafras was the nation’s second largest export, falling just behind tobacco. In Europe it was utilized to treat a variety of health disorders.

Moving into the area of varying degrees of yellow, witch-hazel has the brightest leaves, with each exhibiting a warm, sunny yellow. Witch-hazel is an understory species, rarely rising above a dozen feet. Its undersized stature ensures that an individual passing through the woods will get a close observation, especially of its petite flowers.

This shrubby tree begins to bloom in mid-October and may persist until the closing of November, a rare bloom date for trees. Its flowers are generally unseen though, despite being one of the most common trees in the Hudson Valley. This is due in part to their small, yellow flower clusters that blend into the fall foliage making them nearly perfectly inconspicuous.

The leaves and bark of witch-hazel are potent astringents and have been harvested for centuries for use. Products containing it can still be found in the pharmacy.

The tulip tree or yellow poplar is the tallest tree to be found in eastern forests, rising in height up to 150 feet. It receives its name from the large yellow and orange blossoms that appear on the uppermost branches in the spring that superficially resemble tulips. Native Americans utilized these trees to make their dugout canoes. The soft wood and perfectly straight trunks made this species ideal for such use.

Tulip trees have a slow transition compared to other species. Frequently the upper, leafy portion of the tree is a mosaic or checkerboard of yellow and green, with each individual leaf changing at its own pace. Due to their immense height, most of the in-depth leaf peeping will have to be done on the ground when the leaves have finally become detached. If you look up into its canopy all that will be glimpsed is a nebulous mass of yellow, despite the size of the leaves. Each leaf of older trees is rather substantial, often being nearly as wide as two hands placed side by side.

Black walnut also has a coloration similar to the tulip tree. Aside from its tasty nuts which are readily consumed by animals and man alike, its dark hued wood is highly prized and quite valuable. It’s different from the trees already discussed in that its leaves are pinnately compound, meaning each leaf stalk contains multiple lanceolate shaped leaves that are arranged in an alternating pattern on each side. The stalks very superficially resemble a fern frond.

Anyone who has ever looked beneath a black walnut tree has probably noticed that very few plants can be found growing there. This is not due to a lack of sunlight.

Black walnut is an “allelopathic” species, meaning it produces a substance which alters the growth of other plants. All parts of the tree contain a growth inhibiting substance known as juglone. This natural herbicide is released via decomposing leaves and nut husks, but live roots will also discharge small quantities as well. Juglone is very weakly water soluble, and as a result, this chemical remains sequestered in the soil surrounding the tree and builds up to levels where it prevents other plants from competing with it.

The American chestnut, once one of the most common trees in the eastern U.S. it is now quite rare in our forests. In the early part of the last century Cryphonectria parasitica, a fungus accidentally introduced from Asia, quickly killed off 99% of the trees within a couple decades. Trees are still occasionally found in northeastern forests, but by the time the tree reaches approximately 30 feet in height the fungus will have killed it. The roots can survive the fungus, though, and will regenerate the tree until once again it succumbs to the blight. The historic Bear Mountain Inn was constructed from chestnut lumber taken from dying trees in Rockland County that were part of Bear Mountain and Harriman State Parks.

While it’s usual to see the occasional tree here and there in the woods, small remnant groves are still extant in a few areas. I’ve even seen trees flower in the spring and produce nuts, an extremely rare occurrence east of the Appalachians. These nuts, however, not being fertilized, were half their normal size and abortive. The trees that produced the seeds were discovered studded on the slopes of Schaghticoke Mountain, just over the NY border along the Appalachian Trail in Connecticut. This wild peak with massive boulders, often larger than pick-up trucks, jumbled every which way on the mountain from the base to the 1,330 foot summit, contains an ecosystem very similar to the one that existed across the entire eastern U.S. prior to the spread of the blight. While trees do not attain the height they once did, their numbers are still significant, although still well below the pre-blight range, where every 1 in 4 trees in Appalachian forests was an American chestnut.

The mountain laurel, being an evergreen species like the pines, does not lose its foliage in the fall, but rather retains the verdant luster of the summer. It stands out the most at the conclusion of the season, when most other plants have lost their leaves.  These shrubs look out of place among the russet detritus and scrawny limbs of the forest, but enhance the landscape so much more with their differing ideology. Has spring arrived early or has summer lingered? It’s hard not admire their fortitude and resolve to hold onto what they have earned. This comparatively small shrub stands beneath its lofty kin, ignoring their communal gestures and patterns and follows its own bend. We can learn a great deal from Nature.

In the spring the mountain laurel produces the most exquisite white to dark pink flowers. The whole plant ignites in blossoms.  An entire mountain top may be cloaked in the cologne-like aroma emanating from them. While briefly intoxicating, breathing in too much of this pungent scent may produce a migrane. Despite being nibbled by deer, all parts of this plant are poisonous to humans. And the honey produced by bees primarily visiting them may be toxic to consume.

Very few woody species have violet colored leaves in the fall. It’s the rarest of colors. Yet, maple-leaf viburnum dishes it out extraordinarily well, a full-bodied violet as strong and deep as those “purple mountain majesties” we reminisce about. This plant also fruits around the same time of the color transition. A cluster of berries can be found on most of the taller stalks that comprise the plant. Each grouping contains upwards of perhaps 20 berries that are situated above the brilliant leaves. Berries are similar in appearance to black currants, with a tinge of blueberry.

Ash trees may also produce leaves with a bit of violet to them, but this is the least common color these trees present. Like sassafras, the color variability is high and may be either yellow, orange, red, or violet, with varying degrees of colors intermixed within each individual leaf. Ashes produce a pleasing purplish tint, but rarely does a tree come solely in this hue.

There are several species of ash present in our area and each is being threatened by the emerald ash borer, an invasive species which is responsible for killing millions of trees in upstate New York. They are quickly descending downstate and within a decade most of our ash trees might go the way of the chestnut, leaving us with only memories of what once was. They have already been confirmed present at West Point.

The American beech is one tree worth noting that doesn’t fit into our neatly organized list. Instead of developing a vibrant or intense autumnal color, its leaves very slowly acquire a sober light brown. It’s one of the last species to change, holding onto summer as long as possible. Its stiff and papery leaves are like those within a newly bound book.  Despite them not displaying some grand and lively color these pages are definitely worth reading.

As Americans it should be our passion to immerse ourselves in the scenery and remarkable beauty of our native land, seeking to preserve its continuity whenever possible in an already too fragmented landscape. Our forests and the diversity it contains has no peer elsewhere on this globe. In other areas of the world where deciduous forests exist, few exhibit the color scheme that presents itself here, draping themselves mostly with unspirited yellows and browns that lack both liveliness and intensity. Furthermore, all of continental Europe has only 85 tree species, while the eastern half of the U.S. contains over 110 different varieties.

Adrien van der Donck, an early settler of the Hudson Valley when the region was still under Dutch rule, succintly sums it up: "I admit, that I am incompetent to describe the beauties, the grand and sublime works wherewith providence has diversified this land."