Walking the Berkshires

Whether Invasive or Just In-Migrating; You Cannot Conserve the Status Quo.

There have been some concerns raised in the land trust community that one of the impacts of climate change will be the displacement of some native species by others that are expanding their ranges.  A recent article by Attorney James L Olmsted entitled: "The Butterfly Effect: Conservation Easement, Climate Change and Invasive Species"suggests a number of changes that land Trusts can make to their easement language to anticipate this problem, but the underlying premise that in-migrating North American species "will in many cases be invasive" is on questionable scientific ground.

 It is wrong to think of species and natural communities as static and restricted to where they are today, or were at the time of European contact. 

The term “Invasive” is both relative in space and time and too  broadly applied to North American species that are expanding their natural ranges in response to environmental factors and opportunities.  Birds have been doing this for a very long time.  The black vultures now present in large numbers in Connecticut were not found north of Maryland in the first part of the 19^th century (all those dead horses at Gettysburg gave them a beachhead).  Cardinals were not part of my mother’s Massachusetts girlhood.  Coyotes are filling an available large predator niche after the extirpation of wolf and cougar populations.

The term “Invasive” has more validity when it is restricted  to introduced species,  and then only to  those which  have such characteristics as spreading across spatial gaps, establishing virtual monocultures and multiple dispersal methods.  Having these attributes, species should be demonstrated  to displace and outcompete native species to be considered invasive.  Under this definition, House Sparrows are invasive, but Cattle Egrets which, bless their hearts, got here by crossing the Atlantic Ocean and the Caribbean all on their own, are not.

When I was part of the Massachusetts Invasive Plant Advisory Group that developed criteria to determine which species should be considered invasive or potentially invasive in the Commonwealth, we had a very hard debate about Black Locust (Robinia pseudoacacia), a central Appalachian species which can be problematic in pine barren systems in the Northeast.  Had the glaciers receded a few thousand years earlier, Robinia would likely have expanded its natural range a few hundred miles further north, resulting in a different kind of natural community where it overlapped with pitch pine and scrub oak.  Humans helped it make the jump, planting Black Locust for fence poles (which sometimes resprouted!). 

My advice for anyone drafting a conservation easement or management plan is to start by answering the question; “What are we trying to conserve and managing for?”  The question of invasiveness relates directly to whether a species impacts the viability of conservation targets.  The best example I can remember from my TNC days concerned a fen in NJ that was also a bog turtle site.  The fen had a large and expanding incursion of purple loosestrife (an exotic species non-native to North America).  There were two possible conservation targets to manage for at this site: the rare natural community represented by the fen, and the federally threatened bog turtle species.  The condition of the fen was severely degraded and attempting to eradicate the loosestrife threatened worse disturbance as well as the bog turtles that still were using it, so it was determined not to try to manage the fen as fen, but as bog turtle habitat.  The bog turtle basking areas  were being shaded out by the loosestrife, so the management prescription was to cut the loosestrife stalks by hand each year before they set seed.  This took several days of cutting by hand, but was the best response available to conserve the primary conservation target.

So, if we are managing for rare and restricted habitat types, some of which will not be viable in their current configuration, or indeed in any form with climate change, we are making a choice to prioritize them against the prevailing forces of change.  That may indeed be the right thing to do, but even then the calcareous fens of Connecticut will not have the same species composition and structure as those in Maryland even when our climate changes to that of Maryland today.  There are special gaps that are unlikely to be crossed by native fen species present today in Maryland but not in Connecticut.  That is the beauty of natural variation.  Diversity matters, but it plays out in many different ways from site to site.

Especially with large, “functional” landscapes, the idea is not to manage them to maintain exactly the species types and forest composition of today, but so that they are robust and resilient enough to maintain biodiversity, in whatever forms may be viable in the future.  Invasive plants may well be a factor that needs to be accounted for, but it does not begin or end with a list of species that are “meant to be here” and others that are not.

 

 

Waterfalls

We have some truly spectacular waterfalls here in the Berkshire and Litchfield Hills and all along the Taconic Plateau.  I make a point of visiting as many of them as I can in every season.  Here are a few shots taken during this past remarkably warm and snowless winter of Bash Bish Falls in Copake, NY and Campbell Falls in New Marlborough, MA . 

There is no meltwater this Spring, and many of our flashy, ephemeral streams will likely run dry as the season advances.  Still, something about a cleft in the rock and falling water always feels spectacular.

 

 

Recent Lakeville Journal Stories with my Byline

I had a few pictures and a couple of pieces in the LJ recently.  My last Nature's Notebook column is readable here with free registration.

The blooms of bloodroot have already come and gone, to be replaced by trillium and columbine and wild geraniums as the season advances. Marsh marigolds quiver like yolks in the swampland, and in deep secret places the tips of yellow lady-slippers have emerged from the fens and will grace the next few weeks in golden glory.

I also wrote a story about HVA's River adventure as canoists and kayakers travelled in sections of for the entire length from source to Sound.

The morning air on Sunday was crisp and clean as 14 canoes and kayaks began another day of the Housatonic River Adventure.  Starting May 3, participants on this waterborne odyssey and those who have gathered with them along the route have celebrated the extraordinary work of local conservation groups to protect and care for the river.  

Organized by the Housatonic Valley Association to commemorate its 70th anniversary, the River Adventure is a journey by expert paddlers from the source of the Housatonic River in Massachusetts through the Northwest Corner to Long Island Sound. Events have taken place all along the route to highlight the largely positive changes that are happening within the watershed in response to the commitment of many groups and individuals.

 

A Day in Pictures on the Housatonic River, May 8th, 2011

1. Scott Heth of Sharon Audubon with a screech owl

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2.  Green Man from the Grumbling Gryphens Children's Theater

3.  Nic Osborn and Curtis Rand get ready for another day of paddling from Source to Sound.

4. Housatonic Valley Association River Adventure flotilla sets out at Bartholomew's Cobble on its way to Connecticut.

5. Kayaks and Canoes passing undfer the Bridge on Ramapo Rd. in Ashley Falls, MA.

This week in the LJ

I have been remiss in failing to link to my recent Nature's Notebook articles in the Lakeville Journal, readable here with free registration.  Fair use excerpt of yesterday's piece:

"Sometimes life roils like those hidden high-energy springs that lie below the mountainside, those dark upwellings of silt that pulse with flecks of gold. 

Sometimes it concentrates all its glory in the mottled sides of trout, or a scarlet stalk of Cardinal flower.

I am not needed to bear witness to all this beauty, for it has its own intrinsic value, yet in doing so I revive myself. I look for the unremarked jewels that lie at our feet, and still expect to be amazed by this land I know so well."

Rock, Paper, Scissors

Take a walk outside.  Whatever you see, whatever is growing or blocking your view, can be described as the confluence of three factors: geology, climate, disturbance.

The slope and aspect of terrain, the overburdon of surficial material and composition of bedrock determine habitat and influence growing conditions.  The bedrock geology of Connecticut records the collision of continents and a central rift valley where dinosaurs roamed.  Differences in soil and groundwater chemistry allow calcareous fens to develop in one place, acidic bogs in another. 

There is a close correlation between our remaining farm fields and soils considered prime for agriculture.  There are geological reasons why the landcover in my town of North Canaan is more than 5% mines.

Climate determines vegetative cover, the presence of ephemeral and perennial water bodies, and the seasonal range of variation in air and water temperatures.  It affects the frequency and intensity of weather and the natural disturbance it causes.  Terrain influences climate at the local level, as well as prevailing winds and precipitation.  Hemlocks grow in cool ravines and on shaded north facing slopes, while acidic ridgetops feature scrubby bear oak and pitch pines. 

In my part of Connecticut, the dominant forest cover types transition from central to northern hardwoods, and certain plant and animal species - including red spruce and bog turtles - occur at either the northern or southern extents of their contiguous ranges.  Prolonged climate shifts beyond the range of variation will determine the composition and structure of habitats and whether these species expand or contract their populations.  This year we lacked the proper freeze /thaw conditions to promote maple sap to run for more than a few days.  If this becomes the norm, I will have to put my spiles away and order my syrup from Canada.

Disturbance can be natural or of human origin, and quite often is expressed as the influence of both factors.  Wind-throw, beaver impoundments, wild fire, ice storms and herbivory by white-tailed deer impact patterns of natural succession and select for some species over others. 

Even natural disturbance can be amplified by human activity - introduced forest pests and pathogens, fire suppression in fire dependent communities and overbrowse by deer expanding into the edge habitat provided by development are just a few examples.  Habitat destruction and fragmentation, followed by competition with introduced invasive species, are the dominant factors in the loss of species diversity and ecological disturbance.

The forests of southern New England are second or third growth woodlands, reflecting nearly 400 years of land use history since European settlement.  Even the lands we set aside from development grow and support life today in ways that are different from the virgin forests of 1619 (and even these were managed by native American land use practices).  We are part of these systems, as much as the rock beneath our feet and the rain that covers the land.

Love on the Night of Salamanders

Spring arrived with a week of warm air that coaxed us from our cloistered homes and out into the unaccustomed sun.  It then brought in two days of steady rain, and nighttime temperatures in the low 50s.  This was the trigger that stirred the dormant wood frogs and filled the night with the chorus of spring peepers.  It brought the mole salamanders - yellow spotted along with the rarer Jeffersons/blue spot hybrids, up from their woodland retreats and out across roadways toward their favored breeding pools.  And so, as is our family custom, the children and I joined them in the rain and helped them on their perilous crossings wherever we found them.

Along with the peepers and spotties were a large number of American toads, a pickerel frog, and a lone red eft not yet a newt. We spent two hours shifting live salamanders every minute or two across to the other side of country roads.  We traversed the byways of Salisbury, CT and Sheffield MA where we have learned to look for them during this great migration, and heard many more wetlands resounding in the baritones of wood frogs than we have on other years.

Then we left the road and walked by flashlight in a cool rain through the dark woods to a pond where all was silent but the dripping needles of pines.  There in the shadowy water, though, were amphibians with better things to do with their time than sing.  My daughter and son spotted salamanders swimming in search of each other, and innumerable wood frogs coupling on the surface or in short dives below.  My children, old hands at amphibian watching but new to the procreation that is the objective of their overland journey, were enthralled to see what the fuss was truly all about, spotting egg masses newly attached to submerged branches.

Elias noted matter of factly that he wasn't finished watching the frogs "having sex" when I said it was time to go - prompting me to suggest the synonym "mating" for any discussions of this activity at school.  Emily, the consummate feminist, asked with just a hint of worldly disappointment whether the female was always on the bottom.  I did point out that sexual dimorphism in wood frogs is in the lady's favor, but my daughter knows a raw deal when she sees one.  I am certain if she were in charge of creation the female would get to be on top.  And why not, on a wet spring night when the woods are alive with the procreative urge, let nature mix it up a bit?  Variety is the spice of life.

All I know for certain is that these are magical moments, timed activities not to be missed, and among the finest things I share with my children, and do for myself, at this or any other time of year.

In Spite of Everything, Spring

Next month I will find a reason, and make the time, to spend a day and a night at Windrock, at the big house by the sea.  I will come for the ospreys that follow the herring, riding high in wild, whistling cries on the wind.  I will stand by the Agawam flume and watch the blue backed fish stacking up in the plunge pool, holding fast all together in the current and waiting for the moment to leap. 

The season has been closed for several years now with herring and alewife stocks so depleted, and so watching the fish returning is harbinger and augury both, a prognosis of the advancing season, of new life, and the health of the environment all together.  It happens around my birthday, when the trees are still bare but budding.  I imagine this as a time of solitude, though I may well have a child or two turning me gladly outward.

I went stargazing last night, stepping back from the unhooded streetlamp and into the shadows.  Then I could see those cool, pale fires hung like beads of glass in the branches of the sugar maple.  The night was well advanced, for I am active long after sundown like the owls in the pines.  I saw the promise of crepuscular Spring, Virgo arisen and Orion stepping off beyond the fatal tail of Scorpio.  I saw Saturn suspended off the shoulder of Pollux, like the disembodied self who appears on the wing to pilots fighting gravity.  I saw a whole section of unfamiliar sky, a patch of lost memory, or perhaps never before seen for what it was. 

I remembered the Southern Cross, twisting in the steel trusses of the old wind pump where I perched in the veldt by the waterhole, waiting.  I thought of spinning tales of Norse gods and northern lights while sailing a dog watch with my uncle Rob beneath a rain of blazing meteors in the Gulf of Maine.  Of the wisp lights of June fireflies beyond the garden gate. Of that once in a hundred year aurora that spread above the valley one March night when my parents, sister and I were driving home from dinner.

I am in love with all this.  I let it sweep through my shuttered soul.  I soak it up like groundwater in a dry riverbed, store it against the failure of the rain.  This is how I atone, how I connect.  How I breathe.

NN in the LJ

Last week's Lakeville Journal carried my Nature Notes column on our National Bird, readable here with free registration .  Fair use excerpt:

Bald eagles, wild turkeys, beaver, bear and moose, once driven from Connecticut,  have made promising and even dramatic returns.  Today we live alongside each other — not always easily — but whether encountered in midstream or in our very backyards, these species are evidence of extraordinary resilience and adaptation.  

Not every plant or animal is able to make such adjustments, and habitat destruction remains the single greatest cause of biodiversity loss worldwide. Still, the landscape of northwest Connecticut retains a wild and scenic character, where coyotes howl and eagles soar despite centuries of settlement.  

It is not difficult to imagine a time when even western mountain lions will venture a furtive paw in the Litchfield Hills as they gradually track eastward. Whether we would accommodate the presence of a top predator of their caliber in our neighborhood is an open question, but it is certainly something to ponder. And it certainly makes my heart glad to see eagles here.

Bog Turtle Disease Alert

The federally Threatened bog turtle faces a new threat in the northern portion of its contiguous range.  On August 5th, the USFWS issued an advisory bulletin that an unusually high number of dead and apparently diseased bog turtles have been reported from four states, including New York and Massachusetts.  I received the alert by email from a colleague and the full bulletin is reposted here. 

"...The number of bog turtles found dead in their wetland habitat (2 to 4 dead turtles in each of four wetlands in NY and MA) exceeds that which is typically reported.

In some cases, dead bog turtles have been found entirely intact, with no obvious cause of death.
On several live bog turtles, a grayish or whitish substance and/or discoloration has been
documented on the skin of the head, neck and limbs, as well as on the claws. In some cases,
these appear as skin lesions. Scute sloughing and loss of claws and toes has also been observed.
Based on data collected at a Massachusetts site, the symptoms appear to worsen over time.
At this time, the causative agent(s) of the observed symptoms has not been identified..."

This is extremely troubling news.  When I was with The Nature Conservancy, bog turtle conservation in Massachusetts, Connecticut and part of Eastern New York was a major focus of my work.  The bog turtle is at the extreme northern extrent of its contiguous range in Massachusett.  The USFWS Recovery Plan for the bog turtle's northern population identies just three bog turtle sites in the Commonwealth, but two of them are considered good sites and are under conservation management.  I am intimately familiar with both of these, and know that if one has lost 2-4 adults to a new threat the viability of what would otherwise be considered a strong and vital population is in grave peril.   Past research indicates that the loss of just one breeding adult a year at these sites would be enough to tip the balance toward extirpation.

The 2001 rare species recovery plan records what was known at that time about the threat posted to wild bog turtle populations by disease (my emphasis added):

    "...At present, there are no substantiated reports of disease affecting a wild population of bog turtles, although at one site in Columbia County, New York (J. L. Behler, pers. comm) the number of dead turtles is cause for concern; eight dead bog turtles were collected during three visits to the site in 1988 and 1989 ( A. breisch, in Mt. 2000).  A sick turtle removed from that population and held for several years in captivity tested positive for upper respiratory distress syndrome (URDS) upon necropy (J. L. Behler, pers. comm.).  Although this could indicate a health problem within that communication, it is also possible that the turtle contracted this disease while in captivity.  Disease issues have the potential to become a much larger threat to wild bog turtle populations as they are subjected to more handling by researchers or if manipulation of turtle populations is undertaken through the deliberate release into the wild of bog turtles from other areas, zoological collections, or those seized by law enforcement activities.  It should be noted that thorough health screening of wild-caught bog turtles has not been a standard practice of researchers, although it may be warranted (Smith in iitt. 2001)..."

I do not know for certain whether all four sites where increased mortality and apparent disease have been observed coincide with those where there has been more handling by researchers, but it is highly likely at least at the first site where such observations were made, because very few people besides researchers even know where the turtles are or would know to report what they had observed to the proper authorities.  In the Massachusetts case, only researchers have legal access to the sites.

There is additional publically available data concerning the possibly diseased bog turtle site in new York mentioned in 2001 rare species recovery plan.  Beacham's Guide to the Endangered Species of North America (2000) identifies the respiratory disease at that site as Mycoplasma:

"...Of additional concern is the recent (1997) discovery of Mycoplasma (the bacterium that adversely affects the desert tortoise) at a bog turtle site in New York. This disease has the potential to cause significant declines in bog turtle populations. The site where Mycoplasma has been discovered has been identified as one of the best remaining New York sites and lies in a valley with additional, extant sites leading to the possibility of spread of the disease through a significant portion of the remaining bog turtle range in New York State..."

The USFWS disease alert makes no mention of Mycoplasma and instead describes different symptoms.  That is what is most alarming about this new threat.  An unknown and highly lethal pathogen will take time to analyze, let alone isolate causes and develop a meaningful response. Bog turtles do not have any time.  their populations are too small.

Consider that in 2006, a new disease affecting little brown bats in New York was first described for science. Three years later,  white nose syndrome is causing up to 90-100% mortality in bat caves from the White Mountains of New Hampsive to sw Virginia.  It has affected between 500,000 and 1,000,000 bats of several different species.  There is still no absolute cause for this disease, nor a cure.  One theory is that human activity may have been an initial vector for the spread of the fungus.

I suspect that the reason this new turtle disease has not yet been reported in Connecticut is that no researcher has been to our few remaining (and much poorer quality) bog turtle sites to check. There has not been a live turtle reported from a couple of these places in years.  I am aware that several years ago, one Connecticut turtle was found by a passerby and taken to a public beach where it was spotted by a knowledgable person and ultimately returned to the site where it belonged.  My understanding is that this turtle was later found dead.

This leaves open a difficult question.  Should researchers visit other bog turtle sites to determine whether they, too, have evidence of increased mortality and apparant disease?  Or should they refrain from doing so, given the potential that their activity could be contaminating clean sites?   The felt soles of waders are known sources of introducing the microscopic alga  Didymosphenia geminata or "Rock Snot" to trout streams.  Unless soaked for at least 40 minutes in hot water at least 113° F (45° C) - or for 30 minutes with a 5% solution of dishwashing detergent - what keeps a researcher dry may be killing the very things they care for.