The Red Menace

Euonymus alata, also known as burning bush, is at least a clear-cut villain, unlike  some of the other invasives.    I recall spending a long June day collecting vegetation data in an an immense Euonymus thicket, a former estate  in Wilton. I did not even  observe a catbird, the most common thicket songbird in Connecticut! And beneath the dense bushes, the ONLY plants growing were Euonymus  seedlings.

This species must have high-powered chemical defenses. The glossy leaves look almost artificial (and might as well be), no holes where caterpillars or leaf beetles have nibbled.  Pickings are slim for foliage-gleaning parent songbirds.  No “chain migration”  for this species with a suite of nearly pre-adapted species waiting in the new world, to make use of the new immigrant – and keep it in check, as has happened with the cherries.  Gray’s Manual of Botany (Fernald) shows only two  native  cousins  in this genus, and neither has a range that overlaps southern New England or Long Island.

Euonymus alata, from Asia,  is an effective invader of forests, because it grows well in shade, unlike bittersweet, multiflora rose, everlasting pea, and Phragmites. It spreads well by runners as well as seed. Unfortunately, it thrives especially in the mineral-rich, sub-acidic  soil of traprock (basalt)  ridges.

Euonymus has overrun much of Peck Mountain, in north Cheshire,   because suburban yards on the flanks of the traprock ridge provide abundant seed sources.  As recently as the mid 1980’s the ridge crest and its steep talus slopes were botanically  diverse and special. At that time they were clear-cut  CTDEEP Critical Habitats, per the CTECO website (sub-acidic forest,sub-acidic talus slope, and sub-acidic summit  catgories.) Since then, these habitats  have become near monocultures of burning bush. The Euonymus even thrives in shallow soil pockets on ledges!  Some rare Staphylea trifolia  (bladdernut)  and marginal wood fern remains on the steep west slope  of Peck Mountain, and I last year I noticed a single non-blooming columbine patch.  The oak fern, dwarf saxifrage, and anemonella appear to be gone.

After that Wilton experience and a recent  eye-opening hike on Peck Mountain,   I knew we had to get rid of the burning bushes in our own yard. Emotionally, it was not so easy.  This is a beautiful shrub, especially when crimson in the fall, and it makes a dense, tidy hedge.  The wings or flanges on the stems also look interesting in winter.  Our bushes had special meaning because they been given to us by relatives who were dear to us.

Control  was very quick and simple, from a practical standpoint. We snipped them with a lopper, and painted the freshly cut stems  with Brush-B-Gon (8% triclopyr). For those who simply cannot kill their prize burning bush, thoroughly shearing off the seeds each September, with hedge clippers,  will at least prevent further spread by birds.

Connecticut nurseries are still battling the environmental regulators, to prevent an outright ban of Euonymus alata, because this is such a popular, lucrative species for  the landscaping business, especially for commercial sites.

For illustrations and discussion of other invasive plants, see the accompanying facebook album “Invasives- A Devil’s Advocate Perspective” (Sigrun Gadwa)

http://www.facebook.com/media/set/?set=a.496792513908.273505.588968908&l=ac65ae4d58

Posted in food chain, Invasive Species, Wildlife Habitat | Tagged | Leave a comment

Origins of the Traprock Ridges

The extensive ridgetop hiking trails in central Connecticut are fairly well known, with their fine views, blueberries, and sunflowers, e.g the trails on East Rock, West Rock, Mount Higby, the Hanging Hills,  Cathole Mountain, and Ragged Mountain.  However, remarkably few people who live here realize that the Metacomet and other ridges are  of volcanic origin.  Why isn’t this  part of every high school earth science  class? The geologic processes described below have created a rugged landscape with mineral-rich, subacidic soil,  steep talus slopes (fields of basalt chunks), cliffs, and exposed rock outcrops;  these are all habitats for unusual flora and fauna, including rare species – another fact that is not widely known.

View from the southwest of Cathole Mountain (south end of the ridge, in  Meriden)

Connecticut does not have cone-shaped mountains that once rumbled and spewed ash and lava. Instead the lava oozed more slowly from deep, elongated cracks, that started forming 200,000 years ago, when  the supercontinent, Pangaia, began to pull apart.  Tension between the freshly separated continents caused two elongated cracks (faults) to form. The land settled between two deepening faults, creating a rift valley.  Molten lava oozed up through the deepest cracks and spread across the valley, and then cooled and hardened into traprock (basalt). Three separate periods of lava flows formed three beds of variable thickness.  The middle bed (Holyoke Basalt) may be hundreds of feet thick.

The valley gradually filled with sediment eroded from what used to be high mountains in eastern and western Connecticut. The eastern and western highlands are still many hundreds of feet higher in elevation than the lowlands of the Connecticut valley.  Each successive bed of basalt (cooled lava) was buried by sediment that was compressed into a reddish-brown sedimentary rock, known as brownstone or New Haven Arkose. Total deposition was two miles thick at the Eastern Border Fault in Middletown.  Climate conditions at that time were tropical, which accounts for the red, oxidized color of the sedimentary rock and its low mineral content.[1]

Because the rift valley was still deepening along the Eastern Border Fault (often called the “trapdoor”), the rock beds all tilted down to the east, by 15 to 25 degrees.  The broad basalt beds were glued together by sedimentary brownstone.  Eventually the beds  broke apart into multiple, tilted  “sandwich” chunks.  Over time, especially during the periods of glaciation, the  process of erosion exposed the higher, western, “up-tipped” edges of the these basalt beds, since  traprock is considerably harder than brownstone. The sedimentary“glue” weathered away between the layers of basalt rock. The western edge of each broad basalt slab became a basalt ridge.  A traprock ridge  typically has cliffs and steep talus fields on the west side, and a gently sloping eastern slope,  corresponding to the original easterly tilt of the rock formation.

 The ridges often show an interesting triplet pattern: a central taller ridge corresponding to the thick bed of Holyoke Basalt, is flanked by two much lower parallel ridges, corresponding to the thin slabs of Talcott and Hampden Basalts).  The far north end of Cathole Ridge shows this pattern very clearly.

Most of our  traprock ridges originated as described above, from the western edges of cracked, tilted  lava slabs. However, some “intrusive” formations like Sleeping Giant and West Rock[2] were formed underground. The oozing lava cooled slowly underground, rather than on the surface. In this slow-cooled rock, called diabase, crystals are larger and visible to the naked eye. The  rock weathers more slowly, but mineral composition is identical to basalt. These intrusive ridges were buried by sediment and then exposed by weathering and glacial scour, just like the basalt ridges.

Central Connecticut’s  continuous, above-ground traprock ridge system extends northerly into Massachusetts, but cracks in the rift valley oozed lava as far north as Newfoundland.  Intermittently exposed basalt also occurs in Newark and Hoboken, New Jersey (the Palisades) and further west in the Pomperaug valley in Southbury and Woodbury, Connecticut.

The sub-acidic, volcanic soil on traprock ridges is fine-textured and less acid and richer in minerals, like calcium, magnesium, and potassium- than soil derived from brownstone, granite, gneiss or schist.  Second, the thin soil, rocky outcrops, talus,  boulder fields, and steep slopes are specialized ecological conditions quite different than that found in lowland forest, and are associated with a unique suite of plants and animals.

Partly open glades are characteristic, The “lawn” is actually Pennsylvania sedge, which remains low, naturally. A characteristic suite of plants (besides Penn Sedge) grows in this habitat.

These ecological communities have been designated  as high priority “critical habitats”  by CTDEEP.  However, like  the low public awareness of the ridges’ unusual volcanic origins, public awareness of the traprock ridges’ high conservation value seems surprisingly low, even in the towns where the ridges are major landscape features, like Meriden, Berlin, Cheshire, and New Haven.

Footnotes

[1] An infertile “tropical” soil with a reddish color forms from brownstone parent material unless it is enriched by basalt glacial till or by river sediment.   The well weathered soils of the tropics are also known for their red color.

[2] The name of West Rock (in West Haven and Hamden) changes moving northward, first to Prospect Ridge,  and then to Peck Mountain in North Cheshire.

Photos of the five critical traprock habitats  may be viewed via links to public facebook albums (Sigrun Gadwa).

  • album1    West Peak Summit in September – CT Botanical Society Excursion
  • album2    Traprock Ridge Natural Resources of Central Connecticut
  • album 3   Wetlands Below Traprock Ridges
  • album 4   North end of Mount Lamentation

Symphiotrichum laevis is a spectacular, densely flowering, dry-site aster found on traprock summits.

 

 

Posted in Soils, Wildlife Habitat | Leave a comment

Rose Maze

Yesterday at dusk I was near downtown Wilton, at the site of a future apartment building.  I was trying to get out of  an approximately  2-acre thicket of invasive shrubs and vines, after characterizing them. It was raining hard, so I was clutching my glasses, trying to protect my notebook. (Had not put on the uncomfortable rain jacket, as it wasn’t raining yet when I started my field work.)

Five times I painfully pushed towards the outside, only to reach either a chain link fence, a truly impenetrable mound of multiflora rose, or a pile of logging debris – so I retraced my steps. I prayed on and off, felt like Tom Sawyer trying passage after passage in the cave. Or Sleeping Beauty, having woken up on her own, trying to escape through the thicket of roses that had grown up around her palace.  I remembered another consulting job site:  a tall, impenetrable multiflora thicket surrounding  a small  farmhouse occupied by an elderly  widow. Mowing had ceased when her husband had died.

Eventually, a patch of stately, thorn-free Japanese knotweed (like bamboo) was my gateway to the road and safety, my “prince”. I am so grateful to this grove of invasives, although Jap. knotweed is one of the most villified.

Growing up, I always thought of this plant as a privacy hedge, because the womens’ outdoor shower at the Nissequogue Point Beach Club was shielded from the prying eyes of outsiders by a knotweed thicket. Half a century later, I returned to find the same cold shower and the same dense thicket with large heart-shaped leaves. What a persistent monoculture! Overtime the knotweed at the Wilton site might well replace the multiflora rose (that is if the apartments weren’t built). At least it’s handsome, with bountiful nectar, welcomed by insects in late summer, when pickings are slim elsewhere (before all the goldenrods are in bloom.)

This is the king of the clonal perennial species, and the hardest of all the invasives to eradicate. Even after aggressive herbicide application, sprouts will come up the next year … and the next.  The latest control technique is to drill a hole into  every  tough, hollow stem in the knotweed patch and then inject herbicide into the hole; repeat for three successive years.

Posted in Invasive Species, Wildlife Habitat | Tagged | Leave a comment

Milky Spore Mystery

In about 1990 we applied Milky Spore to our lawn, just once, in the fall, after several years of  trapping Japanese beetles  in funnel shaped plastic bags with flower-scented lures. I’ll never forget the sickly sweet smell after it rained,  and the dead beetles started decomposing! Milky Spore Disease was outstandingly  effective, already the following summer. Over the past 20 years it has been rare to spot even one beetle.

Then why do I keep hearing  reports of failures from various people? We even received a refund from the mail order company the next year, as many people had reported failure. How were their lawns different from ours? I wish a research agency would do a systematic study! In the meanwhile, perhaps internet comments can begin to solve the mystery.

Gadwa Case in Cheshire CT.

1: Our  high beetle population at the time of application must have allowed an initial build-up of high spore concentrations.

2. We live on an exposed  ridge top in central Connecticut – Hardiness Zone 5b.

3. We had used no herbicides or insecticides, but  some  chemical fertilizer (granules about once a season), and had initially added much composted cow manure & peat moss to our four year old lawn.

4. Our soil was a stony, well-drained fine sandy loam (largely subsoil, stripped of topsoil when the house was built), derived from glacial till, sunny in 1990.

If it were only clear how to make Milky Spore Disease work, I’m sure this natural one-time control would be preferred by most to repeated applications of  long-lasting broad spectrum neurotoxins, such as  imidacloprid!    Imidacloprid  is toxic to ALL insects, be they pests or  benign, and harms human health as well.  It  has a half life of up to 730 days, and migrates through the soil.  Imidacloprid is the active ingredient in  Merit, Preen and Bayer Advanced, among others. The new formulation of GrubEx has Chloratranilipole, also a systemic, broad- spectrum insect neurotoxin, toxic to aquatic life – but with less risk to mammals (like us) and birds and somewhat less persistent.

Comments on others’  experiences are very welcome!

Posted in Uncategorized | Leave a comment

Far-Travelling Toxins

 

Sperm and bottlenose whales

Very High Toxin Concentrations found in Arctic Whales

The link  below is  an article sent by a colleague on the surprisingly high levels of toxins, found in arctic whales.   Concentrations of toxic heavy metals like cadmium and chromium, were orders of magnitude higher than the danger levels for human fish consumption.  At every step in the food chain,  a persistent metal toxin (slowly- or non- biodegradable) bio-magnifies (tissue concentration becomes higher).  Metals in road runoff that reach the ocean biomagnify in seafood.  Abroad in many countries, DDT, which persists indefinitely, like metals, is also still used.  Persistent toxins are also transported thousands of miles though the oceans, in currents- potentially the gulf stream-   and by wind-driven surface flows, and  also by migrating fish and whales.  (This is similar to the insecticide bio-accumulation problem  mentioned in my recent zigzag dogwalking post.)

Oil Toxins will not be contained in the Gulf

The take home message: not just the Gulf of Mexico and its  coastal marshes  are threatened by the Gulf Oil Spill, and that threat is not just in the distant future.

http://news.yahoo.com/s/ap/20100624/ap_on_sc/whaling

Posted in food chain, oil spill, PAH, Water Quality, Wildlife Habitat | Tagged , , , , , | 1 Comment

Ailing from Indoor Air Pollution? Go Outside!

This afternoon I heard on public radio (Faith Middleton Show) that  health problems from indoor air pollution are worst in the most energy efficient, air-tight homes (LEED- certified).  I also heard that on average Americans spend less than 95% of their waking day indoors. The Yale PHD interviewed praised his own leaky windows, for the healthy outdoor air they let into his house. (Research was done by Environment and Human Health, Inc. )

This is a very real problem, a major contributor to childhood asthma.  I have heard that it can be addressed without squandering energy by systems of ventilation that include heat exchangers – and by choosing building and decorating materials for minimal off-gassing- like wool rugs – or straw mats, rather than synthetic carpet with backings and  adhesives that generate unhealthy gasses.  It would be great for sustainable farmers to have a stronger market for sheep wool! Faith Middleton pointed out that better labeling of materials is needed, so that homeowners and contractors can make informed choices.

If structural changes are not possible in the short term, it helps to periodically open multiple windows to air the house, on warmer days in winter, and to spend more time outdoors.  My mother did not give me and my siblings a choice; we were sent outside to play and did indeed find interesting things to do.   A diverse natural environment with some wildlife, insect life, and wildflowers will hold your childrens’ interest longer!  Obviously we  breath fresh air while hiking and walking the dog.

Consider also that time spent working in the yard, is time breathing healthier air- typically also with less dust and mold spores than indoor air.  Pulling out lawn weeds, trimming bushes and raking weeds by hand is more time consuming than using power -tools.  It seems to me that the yard would be more inviting to many adults, with greater variety of plantings – and self-seeded plants –  native and non-native,  to keep track of and tend. My husband is not a trained horticulturalist or ecologist, but enjoys spending time outside with me, following my lead, and listening and learning as I point things out.  He now is able to recognize and mow around attractive native perennials – like buttercups and daisies – that crop up in the lawn, even before they bloom!

The outdoors is also more welcoming in summer,  if indoor and outdoor temperatures are similar. At our house in Cheshire, Connecticut, in lieu of air conditioning,  we use airflow drafts though open windows and screened doors, and  shade from an “umbrella” catalpa tree (pruned each fall) on the south side of the house.  Our extended family’s vacation house on Long Island is shaded to the south by two large hemlocks.  It has a long, narrow shape with many windows on both sides, allowing  for excellent cross ventilition. A screened second floor sleeping porch sleeps up to five (on cots) and is a pleasant place to spend time (read, sleep, or just rest and listen to the birds outside)  even in very hot, humid summer weather,  typical of Long Island.

Tomorrow, June 12th,  is the birthday of my brother, who believes lots of  work and play outdoors is the key to good health. We’ll be touring three demonstration alternative “organic” lawns in Newton, Massachusetts (Ecological Landscaping Assoc. http://www.ecolandscaping.org/), one with a solar house.   I expect to learn more ways to spend time outside on my piece of land, and have a fine-looking, dog-safe and wildlife-friendly, “organically ”  landscaped property – fodder for a future blog post. One way I know from childhood is to welcome black locust trees* and clover, which take nitrogen out of the air, by means of symbiotic rhizobium bacteria – free fertilizer! See photo below.

Sleeping porch: comfortable on hot LI nights- and days- in a pre-airconditioning house

*Black locust is on the invasive species lists of some states. It can spread aggressively, fertilize, and change,  sandy infertile natural habitats, as on the Cape in Massachusetts, but in a home landscape , in a pasture, or as a street tree, it is just fine, in my opinion (and that of other Long Island “natural resource professionals” and farmers).  Its abundant nectar is valuable for bees. Black locust  is in fact native to the US –  is from further south and west than Long Island and southern New England.

Posted in Energy efficiency, Invasive Species, Native Landscaping, Soils, Uncategorized, Wildlife Habitat | Tagged , , , , | Leave a comment

Zig-zag Dog Walks

When walking my dog Mackie in our tidy, suburban neighborhood, I zigzag back and forth across the street,  trying to avoid lawns that are aggressively chemical-treated, as Mackie is always “nose to the ground” unless he hears something of interest in the distance.

Mackie and I zig zag between sidewalks that border  apparently safe lawns.   I look for  clover leaves, variably green color (not evenly dark  green) ,  and small, low-growing patches of lawn wildflowers.  This odd behavior is  based on convincing anecdotes I have heard of repeated cases of the same cancer occurring among different dogs with similar exposures to pesticides.  It is also based on my reading of the results of epidemiological studies, summarized in the informative publications of Nancy Alderman’s non-profit, Environment and Human Health, Inc. based in North Haven.  Dogs are even more vulnerable to cancer than children, and we have already lost two family dogs to cancer: Tejana and Poka.   Poka died at Age 11 of jaw cancer, and would have died at 10, without expensive surgery.  Tejana lived to 15, but then during her first five years she was walked in urban vacant lots and on beaches, not in suburbia.

I began zig zag dogwalking after I heard several stories from the most dynamic trainer of organic landscapers in southern New England, Chip Osborne, out of Marlborough, Mass.   He was the keynote speaker at an Ecological Landscaping conference in Springfield, a few years back.  He told the class that he used to work in a greenhouse. His dog would lie under the potting table, with occasional drippings falling on them (with dissolved fertilizer, fungicide, etc.)  The dog, and then its successor, died of the same cancer.

He told a second anecdote: a  lady in a new residential community/cum golf course walked her dog on the lovely course every day. Her dog died of a nose cancer. She got a new dog, and walked the dog along the same route. Her new dog also got cancer, the same type – and she moved out. Of course dozens of fungicides, herbicides, and insecticides are applied to golf courses, so it is very hard to know, without a real epidemiological study. The story teller quit his propagation occupation and went on to start a successful organic lawn care business, and also teaches many training workshops for other landscapers, transitioning to this approach.  He testifies for citizens groups as well.

The man believes in what he teaches; he knows that the organic approach to landscaping is not only better for the bees and other insects and wildife; it is safer for people and dogs.
As John Stuart Mill (1806 to 1873)  said:

One person with a belief is equal to a force of 99 who have only interests”

I heard Chip give an articulate presentation to a Westport land use board,  explaining how one achieves sustainable  affordable lawn care without chemical applications, refuting advocates of tire crumb athletic fields for children.

Besides the  health of children and pets, lawn care practices can affect our water resources.  My  subdivision was built before the days of stormwater management.  Whatever folks apply to their lawns    (e.g., excess fertilizer and pesticides) may also wash over the curb along the pavement into the catchbasins, and thence into the River.

When walking the dog, we use a pooper-scooper or plastic bag, not just to avoid being  verbally attacked by my neighbors, but also to keep the feces from being washed by the rain into the extensive system of catch basins, which dump directly into the streams in our neighborhood.

Not only does our neighborhood have fewer  wildflowers, wild bees and beetles than it used to;  the  tributary streams fed by runoff  (2 mg/l of nitrate last time I tested our stream ) are nearly devoid of life.  The Ten Mile River, dowonstream  also has  fewer aquatic insects to feed  trout , dace,  suckers, and wood turtles.

Friends say: why don’t you just walk your dog  in a park?   Here in north Cheshire, we do have lovely open space behind us, The Ten Mile lowlands are great for hiking and free runs  but only in the non-growing season, unless one is a bird watcher coated with bug spray. We can manage driving Mackie to a park maybe once a week, but not three times a day!  Fortunately traffic levels are low in our neighborhood, except in late afternoon and early morning, so zig-zagging across the much-too-wide road is pretty safe.

It is a relief to visit Ships Hole Farm in Long Island, with no dog-walking constraints related to pesticide anxiety.

Violets and a dandelion- early spring lawn wildflowers at Ships Hole Farm.

As a scientist I do  understand, that we are dealing with possible health risks,  and that the majority of applied chemicals are likely not hazardous to humans.  However, the other matter is that a sustainably managed lawn is a diverse and  interesting mini-ecosystem, and can be lovely as well.  It  dos not harm fauna, like Northern Flickers , song sparrows, flower beetles, honeybees, and moles.  …. more fun to walk past and look at-  and probably safer- than a lawn that receives an intensive turf chemical regimen.

Bluet is a lovely lawn wildflower, with grasslike leaves

Naturalized white violets, an attractive, even low groundcover

Flowering bushes buzzing with bumblebees may also indicate a safe lawn. Sadly,  it is years since I have seen a honeybee in my Cheshire neighborhood and the miniature solitary bees have also become very scarce.  However, I still do find honeybees on vacant lots (just yesterday on Broad Street in downtown Manchester) and in poorer neighborhoods.  On those properties  there is probably little use of expensive, beetle grub insecticides (imidocloprid is a neurotoxin that also harms a great many other insects, including bees.)

Posted in Invasive Species, Native Landscaping, Uncategorized, Water Quality, Wildlife Habitat | Tagged , , , , , , , , , | 1 Comment

Turtle Hibernation Habitat? Soils Data Needed

It would be very helpful to consulting ecologists like me, if more information were available on the characteristics of habitats (soil textures, canopy cover, moisture levels, depths, slope aspects) that are used for hibernation and nesting of the various turtle species in this region. Good southern New England data is available for the endangered bog turtle, but not for the other declining species, such as Eastern box turtle, wood turtle, and spotted turtle, or for common species like painted turtle, musk turtle, and snapping turtle.  This would help land planning professionals make recommendations, such that development and roadway projects and residential improvements could better avoid these habitats, or at least mitigate for the habitat loss by creating similar habitat nearby.

Eastern Box Turtles (Terrapene c. carolina) must hibernate on land, in locations where they will neither be frozen, nor suffocate due to inadequate oxygen.  Even in a torpid state, with slow metabolism, they do need some oxygen.  Developing turtle eggs also need some oxygen.

In Connecticut, E. Box Turtles are missing from the northwestern Litchfield County Hills, where temperatures are cooler and where very shallow, rocky soils are common. The elevational maximum is 700 feet, according to our state’s principal reference book for turtles, Dr. Michael Klemens’  Amphibians and Reptiles of Connecticut and Adjacent Regions, 1993, CTDEP Bulletin No. 112.   E. Box Turtles (EBT’s) are more common in the southern U.S., compared to southern New England and New York State; likely due to less mortality during hibernation. That may be why human poisoning by sequestered mushroom toxins has been reported during strikes among southern Appalachian, but not Pennsylvania coal miners.

In my experience, soil scientists and others do most often find Eastern Box Turtles in the vicinity of relatively coarse-textured soils.  We have found them repeatedly in the deep, coarse-textured (sandy) outwash plains near rivers; also in Long Island and Connecticut Central valley farmland with deep soils.  These soils have a high proportion of pore spaces and, accordingly more available oxygen than fine-textured soils.  They are also easy to dig.  However, I am not aware of solid soils data for actual hibernation and nesting sites in deep coarse or coarse-loamy soils in our region. .

Much of southern New England and adjacent New York state has stony, till-derived soils, often fine textured, shallow to bedrock, or with a hardpan.   E. box turtles may also still locally common in these areas, in East Hampton, CT and Haddam Neck, CT, for example.  In a till-dominated landscape, deep, organic-rich soils bordering forested seasonal wetlands are likely used for hibernation.  Dr. Klemens knows of data, showing soils on wetland perimeters being used in a stony till landscape  in Southeastern New York State (personal communication).  Rotten stumps and logs are another EBT hibernation solution reported by various southern turtle researchers (in summary chapters in books by Ernst and Dodd) and also by graduate students at Central Connecticut State Univ., studying a population on the slope of a trap rock ridge in southern CT.

Friable soils are not only well suited for hibernation, on land, for the terrestrial Eastern Box Turtle, but also for nest-digging by several other  Connecticut turtle species.  A southern or western exposure would seem more important for a nesting site than a hibernation site, but data on slope orientation of both hibernation and nesting sites is sorely lacking.   Most of the above is based on informal observations or a single study. Solid soils and landscape data, with accompanying basic turtle data, is needed to accurately document habitat characteristics of nesting and hibernation sites!

Posted in Soils, Wildlife Habitat | Tagged , , , | 1 Comment

Wood Turtle Habitat Needs

Hibernating wood turtle, briefly taken from the bottom of a deep river pool for data collection.

A sustainable landscape includes the habitat components needed by indigenous plants and animals.  Turtles may carry their homes on their backs, but they still need suitable habitat to live in, in particular,  for hibernation, for nesting, and to sustain their food supply.

Wood Turtles (Glyptemis insculpta ) are semi-aquatic and semi-terrestrial. (See Photos above, of a torpid, hibernating wood turtle.)  They need clean, well-oxygenated rivers or large streams for hibernation, and also for feeding on stream bottom invertebrates, especially in spring and fall.

Like most other turtle species,  they need  sunny areas with well drained soil, easy to dig in, for nesting.

These large, fast-walking turtles also seem only to be found along rivers and streams with  broad, naturally vegetated buffers for terrestrial foraging at least three hundred feet wide on average, in our experience.   As  intelligent, likable turtles (reportedly the most intelligent reptile) and as large, conspicuous species, I suspect they are less vulnerable to collection if hidden in a broad thickly vegetated river valley. This species is omnivorous; while on land it eats plant matter as well as earthworms, which it can trick into emerging from the ground by tapping with its foot to cause vibrations, I have read.

Wide naturally vegetated buffers, along feeder streams as well the main stem, also maintain the species’ key habitat requirement of good water quality with high dissolved oxygen levels,  and stable in-stream habitat, without surges of high flows and spikes of warm water temperatures.  A perennial stream or river that is fit for wood turtles has rocks, sticks, and logs  free of black scum fed by excessive nutrients; it is free of large sediment bars, severe bank erosion, and scouring. It is large enough not to freeze solid in winter. Healthy instream habitat  is needed both for hibernation and also for the Wood Turtles’ invertebrate food supply during its aquatic phase.

Like E. Box Turtles, Wood Turtles (Glyptemis insculpta, formerly Clemmys insculpta) are  on the official Connecticut “NDDB” list; in fact they are even rarer.  They are absent from many suburban Connecticut towns and from Long Island, with few rivers.  (NDDB is jargon for Natural Diversity Data Base).  Spring is a good time to detect presence of a wood turtle population along a large stream or river, because their distinctive tracks will be found on sandy or muddy banks.   Like E. box Turtles , they need oxygen during hibernation.  By contrast, two common Connecticut turtle species, snappers and painted turtles,  have anaerobic metabolism to use during hibernation, usually  on the muddy bottom of a waterway or pond. Another key similarity to box turtles is the fact that both species  spend much of their time foraging on land, and are vulnerable to habitat fragmentation and roadkill.

Found in a hibernation site, a root tangle in a river bank, next to a female

Connecticut has a “Special Animal Form” to be used for reporting occurrences of animal species such as Wood Turtle, E. Box Turtle, and Bog Turtle, that are either rare, in serious decline, or dependent on rare habitats.  I can e-mail you a sample reporting form if you contact me @sigrun.gadwa@sbcglobal.net, and will provide help with records of listed turtles if you share your data with me, as these creatures are of particular scientific and conservation interest to me.  I have a DEP Scientific Collectors permit to handle turtles for collection of  data not required by the CTDEP, such as sex, age (found by counting growth rings), height, and size; please e-mail me if you would like to learn how to monitor populations of listed turtles (volunteer basis).   The Special Animal Form may or may not be downloadable from the CTDEP website, but would certainly be provided upon request via e-mail, by CTDEP Wildlife Division staff, e.g., Laurie Fortin.   An informative scientific overview of wood turtles, as well as Eastern box turtles,  may be found in Turtles of North America by Ernst, Lovich , and Barbour, 1994, published by The Smithsonian Institution.

Posted in Wildlife Habitat | Tagged , , , , | Leave a comment

Turtles are Travelling-Take Care

A sustainable landscape, even a suburban one,  has travel corridors for wildlife, to allow movement to new  food sources, nesting areas, etc. and to prevent inbreeding of isolated small populations (e.g. maintain genetic connectivity within a metapopualtion.)

Once in a great while residents of my town, Cheshire,

Colorful, active turtle, found in a Cheshire Land Trust Preserve

Connecticut, come upon an Eastern Box Turtle. This beautiful creature, whose scientific name is Terrrapene carolina carolina,  has black designs on a background of orange, yellow, or tan.  It is colorful yet surprisingly inconspicuous on a leafy forest floor or among meadow grasses.  Common less than half a century ago, Eastern box turtles are now listed by the State Dept. of Environmental Protection as a Species of Special Concern. They have disappeared from many areas where they once thrived, as suitable meadow and deciduous forested habitat has dwindled and become fragmented. These are potentially very long-lived turtles (sometimes over 100 years.)  However, population trends have been steadily downward since the advent of cars and suburban sprawl. In the 21st century there are more hazards (e.g. traffic, lawnmowers), so that adults die sooner, on average, and lay fewer nests of eggs in their life time.  Fewer eggs hatch because ironically the abundance of nest/egg predators such as skunks and raccoons is higher in suburbia relative to rural American and forestland.  A small, isolated Eastern box turtle population can, sometimes, hang on in a three to five-acre isolated woodlot. One such woodlot was found in Meriden recently, and preserved using CT DEP open space acquisition funds.

But over the long term, genetic problems from inbreeding are likely in an isolated woodlot,  unless a few new individuals can be introduced.  However, captive breeding is  something currently not allowed by the CTDEP Wildlife Division; this seems wise as a carefully designed program is needed to make sure existing populations are not depleted.  I have also read that sometimes introductions can actually cause genetic problems to a long-coevolved inbred population, though the examples  were in  the plant kingdom.

The chances of spotting a box turtle will be highest in the next few months. In the set of records I submitted last fall to CT DEP most observation dates were in May and June or early July, with  one outlier in early April.  These are the months when female turtles of several species venture out of their small, familiar home range and travel to a suitable sunny nesting site with soft, friable soil.  Males also often leave home at this time of year, searching energetically for a mate. (They have ardent red eyes and concave undershells, for better purchase on the back of a female, with brown eyes and flat undershells.)  Most box turtles can be picked up easily and safely, but a male in spring could scratch. Don’t pick up snapping turtles (dull, blackish, compared to box turtles, as you can see from on-line photos); their bite is dangerous.

Most turtle travel takes place on the day after a rain. Eastern box turtles prefer pleasant cool weather for hiking and foraging because they are very sensitive to dehydration. Physiologically they are more like aquatic turtles, than terrestrial tortoises. That’s why they like to move about in the dewy morning, soak themselves in pools and puddles on hot days, and are so often found in lush, moist microhabitats.  Favorite foods are all juicy: strawberries, mushrooms, slugs, and jewelweed. Dr. Michael Klemens, a well-known herpetologist, has New York State data showing that a preferred hibernation site is deep, moist, organic rich soils on wetland edges.

Especially during spring travel, they risk road kill, mower injury, poisoning by lawn pesticides, and kidnapping by well-meaning persons.  If they do manage to lay eggs, more often than not the nest will be predated.   A friend of mine, Tony Ianello, invented an ingenious wire cloth nest protector, with miniature exit doors for the hatchling  turtles, when working for the Quinnipiac Watershed Association (QRWA), as  coordinator of the Turtle Crossing Program, funded by the National Wildlife Foundation. Unfortunately the red tape hurdles precluded its use on this state listed species., or on wood turtle, also a Species of Special Concern.

Note that photo captions do not provide exact locations; this is per CTDEP guidance to prevent collection for the pet trade, or laboratory animal trade- there is still a market, though less than in the past, and less than down south, where they are more common.

Turtle_Xng_Project_mowing_protocol_Version7_1-18-07

Posted in Wildlife Habitat | Tagged , , , , , , , | 2 Comments