Signs of Spring 8: Arriving Migrants

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towhee2.jpgEveryone seems surprised by the riotous weather patterns of the past few weeks. The cold and warm fronts crossing over us have sent temperatures skyrocketing (it was 80 degrees on Sunday!) and then plummeting (22 degrees last night!). They also trigger violent storms and the high winds that shake our houses and forests alike. Even though these weather patterns surprise us each year, they occur each transition season from winter into spring with clock-like regularity. This is a very poor place for plants and animals to rely on temperature as an index of seasonal time!

Migrating birds arrive on the first warm days of late winter or early spring. It is interesting to compare the arrival dates this year (the year of the interminable winter!) with those of 2011. There are some predictable and also some unexpected patterns!

Robins showed up this year in the field by our house on March 13 (they had arrived on February 15 in 2011). This year we first saw red-winged blackbirds in the fields near Northmoreland Park on April 6 (in 2011 we first saw them on March 2). Common grackles came into my yard this year on March 15, but they didn't show up until March 25 in 2011. Towhees (pictured above: photo by D. Sillman) arrived this year on April 5 very close to their April 8 arrival date in 2011. Bluebirds first flew across our field on March 19 in 2011, this year we first saw them in our yard on April 2 but had seen them pretty regularly along Route 780 up near campus for about a month. Last Saturday (April 12) I saw my first cowbird out under the front yard bird feeder (not all arriving migrants are welcome!). In 2011 I didn't record seeing a cowbird until the first of May. And, finally, we saw our first killdeer this morning (April 16) driving to work. The Penn State "roof-top killdeers," though, have not yet returned to our New Kensington campus (in 2011 they were here on March 30 and loudly greeted us every morning as we walked from the parking lot to the entrance door).

So, there were some delayed arrivals this year (robins, bluebirds, red-winged blackbirds, and killdeer) but also some earlier arrivals (towhees, cowbirds, and common grackles). It would be interesting to look at each species' individual migration paths and distances to see if the patterns of the recent weather fronts might be able to explain these observations.
Looking at bird species that will be departing soon from our local habitats, I see a big difference in the movements of the northern juncos this year as compared to 2011. In 2011 the juncos began to thin out (as they headed north) in the warmer days of early March, but then came back in numbers even greater than their winter densities in the colder days of early April. My guess was that they started up to their more northern breeding territories but then came back for shelter and sunflower seed sustenance when winter showed signs of returning. This year, the juncos have not yet started to thin out around my feeders! There was no "false spring" this year to lure them north. They will be heading out very soon, though, I am sure.

To be the first to arrive at your summer breeding territories is a great benefit to a bird. But, the danger of freezing to death in a sudden storm, or being unable to find a reliable supply of food because of an early spring snow makes the early arrival a life-or-death adventure. This year Deborah and I watched some very confused looking robins hopping about on the fresh snow trying to scare up some earthworms that had been so abundant just the day before!

Last year the early warm weather brought out swarms of honeybees and bumblebees a month and half ahead of the blooming of any flowers that might provide nectar to feed them. There were reports of honeybees cleaning out birdfeeders that had been filled with sugar-rich crushed corn, and stranded, frozen bumblebees scattered across lawns and parking lots. This year, at least, the cold weather was more persistent and did not fool these vital pollinators into any self-destructive forays. In 2011, the bumblebees began swarming our deck in the afternoon on April 15. Maybe they'll be there sometime next week!

In all of these species there is a continuous ebb and flow of daring and caution, a continuous re-structuring of adventurous and conservative behaviors which are each rewarded or punished depending on the particulars of the weather patterns of any given year. Some days the early bird WILL get the worm, while on other days that early bird, unfortunately, will not fare so well.

Signs of Spring 7: The First Spring Flowers

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common_chickweed3.jpgWe went down to the Rock Furnace trail of Roaring Run last Thursday to try to get a walk in before the forecast rains began. This trail follows the ravine of Rattling Run and Roaring Run down to its junction with the Kiski River. It is a strikingly beautiful place to walk! It was nearly sixty degrees and sunny when we left our house for the ten minute drive to the trail. Clouds, though, were rolling in quickly, and it was getting cooler by the minute. By the end of our walk a light rain had begun to fall and it felt very good to climb back into the warm, dry car.
At the parking lot of the trailhead common chickweed (Stellaria media) (photo by D. Sillman), one of our first flowering plants of spring, was abundant and in flower.

Chickweed grows especially well in damp, cool habitats like the Rock Furnace ravine, but it can tolerate and even thrive in a very broad range of moisture and temperature conditions. It is a native of Europe that has spread almost everywhere that Europeans have colonized (or maybe just even visited!). It is a cold tolerant annual that can, in areas with mild winters, persist all the way through the winter season. It grows in high latitudes (up close to the Arctic Circle) and at high altitudes.  Its stems hang limply over the ground and are covered with small (1/3"), paired, oval leaves that open during the day and close at night. Rising over the greenery of the stems and leaves are tiny (1/2" across) white flowers whose five petals are so deeply divided that they look ten-pointed stars. Each flower only lives for one day and is capable of self-pollination (a very useful feature in a flower that opens weeks before most insects are stirring!). Chickweed, though, flowers almost continuously throughout its growing season and can on milder days be cross-pollinated by several species of flies. A single plant can make 2500 to 15,000 seeds! These seeds can germinate in the warming spring soils or persist in the soil systems for up to ten years without losing their viability. Chickweed seeds are eaten by many species of game and song birds, and its leaves are consumed by a wide range of mammals. Humans eat chickweed seeds and leaves, too, and brew plant parts into a variety of medicinal teas and poultices.

Thumbnail image for vinyard on the rhine 2.jpgChickweed is an invasive, exotic weed that can be a serious economic pest in many agricultural and turf grass systems. In parts of its native range, though, it is specifically planted to assist the growth of economically important crops. In the vineyards of the Rhine Valley, for example, a place Deborah and I got to visit last summer (picture by Deborah to the left!), the steep slopes are extensively planted with chickweed for erosion and water control and to help keep soil temperatures as consistent as possible for the roots of these delicate grapevines.

Further along the trail we saw spring beauty (Claytonia virginica) (photo by D. Sillman).  In addition to being a very reliable "sign of spring" this beautiful, flowering plant is also edible from its root and thumb-sized, underground corm to its green, leafy stem! A number of Thumbnail image for spring_beauty.jpgreferences describing both food uses by Native Americans and European explorers include spring beauty (especially its carbohydrate rich corm) as an important food item. It would seem a shame to pull up and destroy such a delicate flowering plant for such a tiny meal, but if you were really hungry I suppose beauty must yield to calories.
At the Mc Inerney #6 gas well about a quarter of a mile down the trail, a tall, south facing, concave hillside acts as a heat collector and almost always drives spring plants to grow and flower days to weeks ahead of other area sites. Here we saw our first yellow, dandelion-like Thumbnail image for coltsfoot1.jpgflowers of coltsfoot (Tussilago farfara) of the spring (although I then saw more in a roadside ditch on the drive home!) (photo by D. Sillman). Coltsfoot is another introduced plant species from Europe and Asia that probably came into Western Pennsylvania with the first European settlers. It is a plant with a number of traditional, medicinal uses but is a potent source of alkaloids that can be toxic. Coltsfoot is unusual in that it flowers long before it sets its leaves. So, if you see a yellow, dandelion-like flower and no surrounding leaves, it's probably coltsfoot! Coltsfoot is classified as an alien exotic plant and can be an invasive "weed." It is a welcome blast of yellow, though, in these still very brown days of early spring.

Spring cress was also in flower still further down the trail, and Deborah also saw a mourning cloak butterfly that fluttered down from its usual tree branch fly-zone to swoop a few circuits around her head. The adult mourning cloaks hibernate in tree holes and in tiny crevices under loose tree bark. They fly out on warm spring days looking for sugar rich runs of tree sap (their favorite food!) and then return to their hibernaculae at night. They will soon mate and lay the eggs that will hatch into the fast growing caterpillars that will in turn metamorphose into the next generation of adults by June or July. (see the species page about mourning cloaks on the Virtual Nature Trail).

The forest floor is still mostly brown and waiting for big spring events like the rise and opening of May apple plants. The persistent greens of the Christmas fern and the evergreen wood fern make up most of color across the monotonous browns of the dried leaves and downed branches. Soon, though, there will be trillium! Soon there will be tanagers and grosbeaks! My red maple next to the street flowered a few days ago, but the maples out in the woods look to be a week or more away from flowering. The hill sides will turn red with all of their buds and blooms!

Last weekend I saw my first towhee of the Spring! He was a very striking male hunting around in the grass around our raspberry patch. And, as I write this, I am listening to the whispy song of the white-throated sparrow. The male sparrow is out in my arbor vitae hedge singing his territorial aspirations for the entirety of my backyard. His song is spring itself, and it is more than enough for today!

Signs of Spring 6: The Spring Moons

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(some parts of this blog were previously published in a 2008 essay)

Full_moon_night Luz A. Villa Wikimedia.jpgThe full moons of the year have long lists of descriptive names that reflect the occurrence of important ecological events that affected early human cultures and societies (photo by Luz A. Villa, Wikimedia). Much has been written about the names given to these full moons by the various Native American tribes.  Hal Borland 's book "Twelve Moons of the Year," and Phil Konstantin's web site "Indian Moons"  list these moon names and relate them to both the various tribes' appreciation of the environmental changes going on around them and also the tasks they faced related to their survival.

The full moon of March (which this year occurred back on March 16) has many names. The Algonquins called it the "catching fish" moon, while the Omaha and the Cree called it the "little frog" or just the "frog" moon (we will have to wait a few weeks more, though, before the frog choruses begin to grace our evenings!). The Kiowa called it the "bud" moon, and several other tribes referred to it as the "crow" moon after the increased vocal activity of the flocks of crows as they sorted out their social and reproductive hierarchies after the long and stressful winter. And finally, a number of the more northern tribes called it either the "crust" moon after the icy snow crusts that formed due to the daytime thawing and nighttime re-freezing of the surface of the persisting snow pack, or the "sap" moon after the rising sap of the trees (especially the sugar maples!) which, interestingly, is triggered by the same daytime warming and nighttime freezing cycles that cause the snow crusts.   

The name that is most frequently applied to the full moon of March, though, and which has been attributed to various, but never specifically named, Native American sources, is the "worm" moon.

We had out first, warm, wet morning of the year just a couple of days ago. On almost every sidewalk, driveway, or parking lot there were a significant number of "earthworms" of various species wiggling along on the wet surfaces, moving in apparently random directions out from their former burrows in the surrounding grass. Why are so many worms emerging all at once? It's probably a behavioral response to moisture and temperature variables that helps to disperse and expand the boundaries of an earthworm population (no, they are not drowning in the wet soil!)

The arrival of the large, migratory flocks of robins is often coincident with this worm emergence event (although this year the robins arrived before the worms had risen!). Watching the foraging robins voraciously eating worms really gives you a good idea of how many earthworms are actually slithering along on or just hiding beneath the soil surface. Many bird species (including the grackles that I described in a previous posting) also opportunistically and with less time and effort investment than the robins, catch and consume earthworms. European starlings, an alien invasive bird species, have even been known to follow the hunting robins at a distance and then, on seeing them grab a worm, dive at them noisily so that the worm is dropped when the startled robin flies away. The starlings, then, get a stolen, protein-rich, meal. This is only one of the ecologically disrupting things that starlings do, but that's a topic for another essay.

As many of you know, I studied earthworms very intensively in my Ph.D. research and in a variety of studies here at Penn State back in the 1980's and early 1990's.  So, a "worm" moon should have some special meaning to me, and, I admit, it does. But, it is not at all clear to me how Native Americans  had any ecological or historical connection to these worm species since almost all of the organisms we call "earthworms" are, like the European starling and the gypsy moth and Colt's foot and so many other species of plants and animals, organisms that have been introduced to North America by European settlers as they spread across the forests and plains of the continent.

Earthworms improve the stability of a soil's structure and its drainage properties, and they also accelerate rates of leaf litter decomposition and nutrient cycling (don't get me started on this!). Aristotle called them "the intestines of the Earth," and Charles Darwin spent many years of his life intensively observing and describing their activities and their extremely positive influences upon soil fertility. My own research described the immense benefits that robust populations of earthworms could have on leaf litter decomposition in established forests and field ecosystems, on re-forested strip mines, and in the cycling and rehabilitation of sewage sludge.  A few years ago, though, an article in the Science section of the New York Times described some of the more negative consequences of the extremely active shredding and burying of leaf litter in worm rich soil ecosystems. The loss of leaf litter habitats for a wide variety of other invertebrates, the loss of the protective, soil covering leaf litter "blanket", the change in the nature and energetics of the leaf litter decomposition webs, and the changes in the way that organic materials are distributed through the soil profile were all attributable to the activities of these alien species. The soils of what seem to be undisturbed ecosystems were, in fact, irrevocably changed from their original conformations by the actions of the introduced earthworms. 

An earthworm as exotic, invasive species is a concept that will take me a bit of time to get used to.          

So, how could Native Americans describe the mass emergence of earthworms in the spring and relate it to the March moon if these earthworm species didn't arrive in North America until possibly the Seventeenth or even the Eighteenth Centuries? I don't think that they could or did. And, careful examination of Konstantin's encyclopedic lists of specific tribal moon names backs up this idea. No specific tribal designation for the March moon includes the "worm" moon.  Fish, frogs, buds, crusts, crows and more are listed, but no worms. My feeling is that the "worm" moon is, like the worms themselves, an imported thing brought by the settlers from their European homes that quickly became incorporated into the structure and perceived history and ecology of their new environment.

Did the increasing abundance of the earthworms cause the American robin populations to massively increase in number? Did the earthworm activity change forest soil properties to then favor other tree species? Did the cleared land that was then plowed into farm fields become more productive because of the swelling numbers of earthworms? Did the earthworms cause the extinction of some litter dwelling beetles and other insects? Did the competitive pressures exerted by these extremely active earthworms drive native annelid species into their very restricted present day distributions?

What interesting ideas! I will need many more years of observing and experimenting to even begin to figure even some of them out!

 Happy worm moon, everybody!

 April's full moon, by the way, will occur on April 15. This moon is the "grass" moon according to the tribes of the "Sioux," the "leaf" moon of the Kiowa, and the "flower" moon of the Cherokee. It sounds beautiful, indeed. I am ready for April with its green grass, green leaves, and its lineup of so many flowers.

I had other things to talk about: the red maple buds are starting to swell and the activity of the birds at my feeders is changing. I haven't yet seen the killdeer up on campus or the towhee in my yard or field. They are coming soon, though.

More soon.

Signs of Spring 5: Return of the Ticks!

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deer_tick_female.jpgYesterday evening Deborah found her first deer tick of the season. She had been working out in the yard clearing leaves and downed sticks from the yard, and later found an adult deer tick attached to her leg. She removed the tick (directions for removal are provided at the end of this blog!) and put it into a jar of isopropyl alcohol, and, being a good biologist, brought it up to campus, took its picture through a dissecting microscope (photo on the left!), and added it to the Penn State New Kensington Invertebrate Collection. 

Below is a composite of the two blogs I sent out last Spring and Fall in which I discussed deer ticks. For those of you who are interested in more information about Lyme Disease, one of my students is presenting a research poster about it at next week's Research and Creative Exposition at Penn State New Kensington. The Exposition is Tuesday, April 8 from 1 pm to 3 pm in the Field House on the Penn State New Kensington Campus. Please come! 

The "black-legged tick" (sometimes called the "deer tick" or the "bear tick") is most precisely named Ixodes scapularis. It is a small, common tick found throughout the northeastern and north-central parts of the United States. It is also a transmission vector for a number of bacterial and viral pathogens including the bacterium that causes Lyme disease, Borrelia burgdorferi. 

The life cycle of Ixodes scapularis stretches out over two or sometimes three years. Eggs laid in the fall in low, grassy or scrubby vegetation hatch the next summer into the very small, six-legged larva life forms. These tiny ticks typically seek out small hosts (like a white-footed mouse or a bird) but are able opportunistically to attach to larger mammals including humans. These larva, though, are not born with any of the pathogens associated with Ixodes scapularis and are, thus, unable to transmit any of its diseases. If these larvae feed on a host that is carrying one of I. scapularis' bacterial or viral pathogens, though, that tick will become infected with that disease causing agent and will carry it and be able to transmit it throughout the rest of its life cycle.

After the larva has taken its blood meal it molts into the larger, eight-legged nymph life form. This molt often is delayed until the following spring. These nymphs, then, seek a host for their blood meal. These hosts are usually mammals ranging in size from white-footed mice to deer to humans. Because of the timing of this nymph emergence the spring (May and June here in Western Pennsylvania) is a time of great risk for ticks bites (and disease transmission) for humans!

After the nymphs have taken their blood meals they molt into adults. These adults are especially abundant in the fall. These much larger life forms (like the tick in the picture above) typically attach to large mammals (like white-tailed deer or humans). The female adult ticks take a large blood meal from their hosts and then use the energy from this feeding to make eggs. The adult male ticks attach to the same hosts, but do not feed (and, therefore, do not transmit pathogens). They are there to find a female and to mate! The males die shortly after mating and the females die after dropping off of their hosts and laying their eggs in the grassy and scrubby vegetation. Those eggs then overwinter and hatch in the summer to start the life cycle all over again..

The number of Lyme Disease cases has greatly increased in recent years. The reason for this increase is attributed to increases in the most critical host in the black-legged tick's life cycle: the white-footed mouse. Fragmentation of forest habitats and the optimal conditions of suburban ecosystems for these mice along with significant declines in their natural predators have led to great increases in their numbers. Black legged ticks, then, in their larval and nymphal life stages are very likely to find a white-footed mouse on which to feed. These mice are also significant reservoirs for the bacterium that causes Lyme disease, so the ticks have a very high probability of assimilating and then passing on these bacteria. 

In 2011 Pennsylvania led the nation in the total number of cases of Lyme disease. Per capita numbers put the New England states ahead of Pennsylvania in disease occurrence, but it is a significant health problem throughout our state. The Center for Disease Control (CDC) has increased its estimate of the number of Lyme disease cases nationwide from 30,000 to 300,000 per year. Recommended therapies for Lyme disease have expanded from 10 days of antibiotic therapy to 30 or more days of treatment. There is also now a recognized Post Treatment Lyme Disease Syndrome in which debilitating symptoms of the disease can persist in patients for many years.

It is important to remember that the black-legged tick is not able to begin its blood feeding until after it has been attached to its host for at least 36 hours. Careful examination for ticks and their rapid removal is the best way to prevent contracting the Borrelia bacterium. Tick removal is best accomplished using a pair of forceps or a v-slotted, commercial "tick-remover." Gently pull the tick from its spot of attachment making sure that you remove the feeding structures (the "head") along with the body. Then dispose of the tick in whatever creative way you might wish! Ways to prevent tick attachment include wearing long pants and long-sleeved shirts when out in the woods or fields. Also, using DEET-based insect repellants on socks, pant legs, etc. reduces the chance of tick attachment. A thorough "tick check," though, after being out in a potential tick habitat is a very effective way to reduce the chance of infection.   There is a vaccine against the 36 known species of Borrelia in the works. This vaccine has passed early clinical trials and, hopefully, will be available soon to help prevent this potentially debilitating disease.    

The black-legged tick is an unfortunate sign of both spring and fall. Let's hope that soon we won't have to worry about them when we go out hiking in our beautiful forests and fields.

Signs of Spring 4: Turtles, Crocuses, Birds, and an Arboretum

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turtle_eating_strawberry.jpgTo me nothing says "Spring" better than my box turtle, Spider, waking up from his long, winter torpor. Here is a picture that Deborah took of Spider savoring a strawberry. As soon as we get a real "worm moon" (maybe this Friday night?), I will add some nightcrawlers to his menu!

My front yard is really starting to come into Spring this week. The crocuses are blooming in the warmed microenvironment next to the brick front of my house. They open on the sunny "warmer" days and close up at night and during the (more frequent) "cooler" days. Crocuses, like most of the early spring plants, have built-in protections against freezing. Their high sugar content can reduce the freezing points of their tissue fluids to as low as 20 degrees F, and special antifreeze proteins (like the ones I talked about in the snow fleas in a previous blog!) block the connections between the freezing water crystals.

The male cardinals have joined the male titmice and white-throated sparrows in a morning display chorus (the Carolina wrens have been singing all winter!). When I go out in the morning to fill the bird feeders their songs swirl all around me (telling me, I am sure, to hurry up and get the feeders loaded up!).
P1060821.JPGLast week, Deborah and I spent a few days up at State College for some meetings and a conference, and I was fortunate to find a few hours to visit the Arboretum at Penn State.
The arboretum is on the north side of the Penn State University Park Campus across Park Avenue next to the new Law School building. This facility has been in the planning stages since the mid-1990's but its initial component, The H.O.Smith Botanic Gardens, officially opened in 2010. The total area of the arboretum is 370 acres and includes open fields, established woods, and many recently planted species of trees, shrubs, and garden plants. Most of the trees are, of course, quite small (mostly 5 to 6 inches in trunk diameter and at most 8 to 12 feet tall). A notable exception to this young array of trees is the almost 50 year old white oak (not pictured - it is called the "Hosler Oak") that was transplanted from its original Lancaster County location in spectacular style (with the help of a 50-ton crane) in 2005. The overall appearance of the arboretum, then, is very open and at first glance almost empty, but the quality and future of the place is obvious once you start to look around.

P1060829.JPG The circular walking path of the Smith Botanical Garden is ringed with a nearly continuous planting of Western Red Cedar. Stepping through one of the many openings to the path you feel the functionality of the coniferous windbreak around you. There are over 17,000 individual plants of 700 different species in the arboretum. Many of them, of course, are not terribly obvious here on the cusp of the waning winter. The many deciduous trees are bare of leaves or flowers and with the exception of some hardy daffodil tips, most of the herbaceous plants are still hidden underground. The evergreen conifers, though, looked green and wonderful! There were species of pines, firs, spruces, and junipers from all around the world. The subtle variations in their needle patterns and colors and their incredible varieties of growth forms were fascinating to look at. Their contribution of "green" to this cold, windy day was most appreciated. The drooping Alaska cedar, the round, low Bosnian pine, the bulbous almost glandular looking Mugo pine (pictured above), and the long branched, sparsely needled limber pine (and so many more!) kept my mind away from the cold temperatures and the steadily blowing wind.

The southeast side of the arboretum that borders on East Park Avenue is a large, bowl-shaped meadow called the "Ramage Marsh Meadow." It is named after Jim and Lynn Ramage of Ford Cliff, PA who are great supporters of both University Park ventures and also our own New Kensington Campus. The marsh meadow is designed to gather the surface run-off water that had once flowed freely down the gentle slope of the Big Hollow valley in which the arboretum and the surrounding neighborhoods and campus buildings sit and hold it so that it can percolate down into the underlying aquifer. The soil of the meadow is dry and firm most of the time, and its grasses, ringed by red-stemmed dogwood, willows, and other moisture loving trees and shrubs, move in attractive swirling patterns with the passing breezes. The graduating class of 2010 donated a boardwalk that bisects the center of the meadow. Views north and south from the walkway give you the feel of a very unexpected prairie-like ecosystem.

P1060838.JPGMy favorite part of the Ramage Marsh Meadow, though, was the cluster of dawn redwoods planted on the northern border. The dawn redwood is a deciduous conifer so the trees were bereft of needles, but it was wonderful seeing these "living fossils" growing so well in Pennsylvania. Prior to the 1940's dawn redwoods were only known from their very extensive, 65 million year old fossils! Finding living specimens of these trees growing in small, remote clusters in the mountains of China was the dendrological equivalent of finding a mastodon or Tyrannosaurus rex living in some isolated canyon or mountain range. These dawn redwoods may grow to over 200 feet tall and in their prime will make a dramatic entry point into the meadow. We'll have to come back in 2114 to see how they have fared!  
The look and feel of the Penn State Arboretum is of a place that is beginning. Last summer I visited a botanical garden and arboretum in Basil Switzerland that dated back to 1589! Among their very mature trees they even had a 110 year old giant sequoia (over 100 feet tall) that they had brought from California. It towered over the lush elms and willows and horse chestnut trees of the garden. The mature, "finished" feel to these Swiss gardens, I am sure, will be the eventual outcome of this new arboretum.

Will tonight be the rising of the earthworms? I will let you know next week!

Signs of Spring 3: Temperature Changes and Birds

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Lesser_Sandhill.jpgA few mornings ago it was five degrees here in Apollo with a minus eight wind chill and swirls of falling, icy snow pellets. The next afternoon it was 61 degrees with bright blue skies and abundant sunshine. An amazing swing in just 36 hours!

Last week in New Mexico we ran through a similar temperature fluctuations over just a couple of hours as we hiked through the winter-cold in a snow storm at the top of the Sandia Mountains, and then strolled in the spring-mild in the greening vegetation alongside the Rio Grande, and then walked in the summer-warm bright sunshine and 70 degrees on the sidewalks of Albuquerque (we dressed in layers that day!).  It does challenge your body and mind to flip through such drastically changing environments so rapidly.  We are hoping that we stay in Spring-mode here for a while (but I already have seen the snowflakes ahead on the five day forecast!).

We missed the migrating flocks of sandhill cranes while we were in New Mexico (photo above by Frankyboy5, Wikimedia). They had been in the fields and wetlands along Albuquerque's section of the Rio Grande for the past several weeks but had moved on toward their northern breeding ranges just a few days before we arrived. I last saw sandhill cranes when I was at Texas Tech taking ornithology forty years ago. They were the highlight of a very cold, mid-February, early Saturday morning field trip to the wetlands outside of Lubbock.  

Roadrunner_running.jpgWe did get to see the state bird of New Mexico while we were in Albuquerque, though. The greater roadrunner is a large (two feet from beak to tail), lean, bird with long legs and a distinctive head crest of feathers. They run rapidly after their prey (insects, spiders, small rodents, lizards, and snakes)and can reach speeds of up to 26 miles per hour (substantially slower, by the way, than the top speed of a coyote!). They also eat seeds and fruit and can be found not only in the dry shrub lands around Albuquerque but also in its residential areas. One in particular has made regular appearances around our daughter's house near the University of New Mexico. He didn't show up while we were visiting, though, so the only greater roadrunner we saw was at the Albuquerque Zoo (photo by El Brujo+, Wikimedia).  

But, there is bird news here! The robins have arrived in Apollo in force this week. There is a large flock variously occupying the still-bare tree branches and the leaf-covered grass of my lawn and field. The leaves on the ground are quite a draw for the robins, in fact. They spend a great deal of time flipping through the leaf layers with their beaks and feet looking, I assume, for insects or worms. Their focus and continued activity makes me think that they are finding something there to eat. This is another piece of supporting evidence for leaving the autumn leaves where they fall, or at least piling them up in corners of the yard rather than burning or discarding them. The leaf piles are a great overwintering site for insects and other invertebrates and a much appreciated smorgasbord site for the early spring birds! 

Thumbnail image for Thumbnail image for grackle_cropped.jpgCommon grackles have also arrived in southern Armstrong County (photo by D. Sillman). Most bird distribution maps indicate that the common grackle is a year-round resident of Pennsylvania, but the grackles that visit my feeders through the spring and summer definitely spend their winters somewhere else.  A small, noisy flock of grackles descended upon my sunflower seed feeders and bird baths a couple of days ago and have been back each day for a not so leisurely meal and drink. Many of the grackles glean seeds from the ground but a few more acrobatic individuals balance their long bodies up on the tiny feeder perches and contort themselves to get some seeds. The resultant tipping and shaking of the feeders spill abundant seed for the ground feeding birds and may represent some type of intentional (but probably accidental) altruistic synergy for the group. The smaller birds (the cardinals, the chickadees, the titmice, and house finches) keep their distance from the decidedly dinosaur-looking grackles. The caution shown by these birds is quite justified as grackles do have a reputation of not only raiding the nests of many song birds but also killing and eating smaller, adult birds.

Many people feel that the common grackle is a pest. They do considerable damage to crops (especially corn) and are so aggressive that they even chase blue jays away from feeders. I am more tolerant of grackles than most, however. Back in the early 1990's when we were having outbreaks of gypsy moths here in Western Pennsylvania, I watched grackles pick gypsy moth caterpillars off of my spruce trees and take them out into our street where they beat them on the rough asphalt to remove their irritating body hairs. They then gobbled up the denuded caterpillars. The grackles would stay busy all evening doing gypsy moth eradication. You have to admire the genius (is the street surface a tool?) and the vigor of this species!

 Another, but not altogether welcome sign of the approaching spring is the emergence of the hordes of brown marmorated stink bugs that have been overwintering in the hidden spaces and tiny crevices throughout our house. Each even slightly warm day stirs a dozen or so stink bugs out of their winter torpor. Deborah and I have been scooping them up and tossing them out the nearest window. We're hoping that most of them will freeze during the frigid nights. Their abundance and persistence are daunting, though.

I will keep looking for the elusive signs of spring! Next warm evening the earthworms will undoubtedly rise up, but that's a topic for next week.

Signs of Spring 2: Biodiversity

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Polypody ferns growing on Rock Furnace Trail near Apollo, PAI Googled "biodiversity" and got a list of 14,600,000 web sites (in 0.17 seconds!). These sites defined the term ("the variety of life in a habitat, ecosystem, or the world") and gave many specific examples (the biodiversity of this exotic island or that sheltered natural area etc.). The list also contained many recent and a few not so recent news stories about biodiversity and species abundances. I also found, as I clicked through the pages and lists, a very neat set of quizzes that tested my knowledge of biodiversity. Like the Pittsburgh Eagle Cam I talked about last week, these quizzes are a great way to waste a great deal of time! There is, of course, a thin, wavering line between questions about biodiversity and questions about biological trivia, but all of the quizzes are great fun.  I will add a few questions (taken mostly from the Biodiversity IQ Test from Foothill College in California) as we go along today (answers are at the end of the blog!) (photo above by D. Sillman: Rock Furnace Trail, Armstrong County, PA).

1. Which of the following actually exist?
a. Ants that "herd" aphids for food
b. Slime molds that creep across the ground
c. Trees that can grow with their roots under water
d. None of the above
e. All of the above

Urban ecosystems seem the antithesis of biodiversity, but an extensive study looking at the impact of urbanization on the diversity of plants and animals recently published in the Proceedings of the Royal Society B: Biological Sciences highlighted many important aspects of city ecosystems. One standard hypothesis attached to urban ecosystems concerns the overwhelming structural similarities of cities around the world. Since the physical habitats of these cities are so similar, the hypothesis states, they probably favor a limited set of species that are hardy and very generalized in their food and habitat preferences. Cities, according to this hypothesis, should all have very similar biotic communities. This idea, though, was not supported by this recently collected data.

Looking at the plants and bird species of 110 cities around the world the study emphasized that each urban area retained a unique set of endemic ("native") plant and bird species.  These species combined with a number of shared, "urban-tolerant" species generated unique biodiversity profiles for each urban area. Cities, of course, had fewer plant and animal species than surrounding "natural" areas, but cities were shown to support nearly 20% of the world's bird species and 5% of the world's plant species. Urban areas were far from the "biological deserts" that they have often been hypothesized to be.

2. What is the most serious threat to biodiversity?
a. Scientists collecting specimens
b. Habitat loss
c. Tourists
d. Pollution

Last spring and summer Deborah and I explored one aspect of the biodiversity of Harrison Hills Park in northern Allegheny County. We visited the park at least once (often twice) a week and photographed and identified the wildflowers along its many miles of trails. We expected not to find that many wildflower species because of the extensive human use history of the park and its relatively recent conversion into a green space. At present, though, the species count from the park is 150 different wildflowers! A very respectable magnitude of biodiversity, indeed! (I highly recommend that you visit Deborah's web site where she features her photographs and species identifications of these wildflowers:

3. If you decided to throw a party to celebrate the diversity of life on earth and wanted to send an invitation to each known species on Earth, how many invitations would you need?
a. 150
b. About 3,000
c. 652,983
d. More than 1.5 million

4. If you wanted to throw that same party for ALL of the species on Earth (both described and not yet described) how many invitations would you need to send?
a. 1.5 million
b. 4.3 million
c. 6.9 million
d. 8.7 million

I am, as usual, looking out the window over my writing desk. The scene outside is dominated by sunshine and brown leaves covering brown grass. It is edged by twenty-foot tall arbor vitae, fifty foot tall spruces, a long stand of crabapple trees, two American chestnut trees, and several tall, thin, scarlet and white oak pole trees. Each year, I have added (but mostly abetted by just not removing naturally planted seedlings) new trees into this mix. I have mostly through inaction helped this yard's vegetative and structural biodiversity and now have great numbers of cardinals, song sparrows, titmice and chickadees, blue jays and woodpeckers (I saw the pileated woodpecker pass through this morning!). Adding a food source, adding a year-round water source gets species to start lining up looking for a spot to nest or den up.

One of the lessons learned from the Urban Ecosystem study and from our Harrison Hills Park collections and my observations on my back yard is that a habitat that is left alone and allowed to repair itself will in a short period of time be occupied by an increasingly diverse community of plants and animals.

5. If we gave a prize for "the strongest creature for its size", which of the following would win?
a. Bobcat
b. Bald eagle
c. Ant
d. Turtle

6. Which of the following environments on our planet are too harsh to support life?
a. Boiling sulfur springs, where temperatures are commonly 212 degrees Fahrenheit.
b. Deep-sea hydrothermal vents called "smokers" where the temperature can reach 662 degrees Fahrenheit.
c. The frigid ice of the Arctic and Antarctic
d. All of the above
e. None of the above

So, this has been a bit of a ramble. With the unfolding spring we will see more and more species around us. But what is the purpose, what is the "use" of biodiversity? There are many answers to that question. Diverse ecosystems tolerate disturbance and stress better than simple ecosystems. An ecosystem with a rich biodiversity will house the vital pollinating species that we need not only for our wildflowers but also for our food crops. A diverse ecosystem will recycle nutrients, generate oxygen, absorb carbon dioxide, and clean up our water and air. A diverse ecosystem is full of species that have unique genes and proteins that may be the tools for our ultimate survival on this rapidly changing planet.

Most of all, though, a diverse ecosystem fills us with joy and awe and connects us to the continuity of life and living on Earth.

Answers to quiz (most answers taken directly from the Biodiversity IQ Quiz, Foothills College, California)
1.  Which of the following actually exist?
d. all of the above

Certain kinds of ants eat the sugary substances excreted by aphids, which are insects that suck plant juices. The ants actually herd colonies of aphids by moving them from place to place and protecting them from enemies. Some slime molds have two distinct phases in their life cycle. In the reproductive phase they are stationary, like a plant with a stalk. From this stalk they produce spores. These slime molds may also exist as mobile amoeba-like organisms that feed by engulfing material. Bald cypress trees grow in swamps in southern Illinois, as well as in the southern United States. These huge trees can grow with their roots continually submerged because of their unique feature, called "knees."
2.  What's the most serious threat to biodiversity?
 b. habitat loss

All over the world habitats are being turned into agricultural land, harvested for wood and fuel, and destroyed or changed to build roads, schools, malls and other human developments. Because the human population is growing so quickly and consuming so many natural resources, habitat loss is occurring at a rapid pace.
3. If you decided to throw a party to celebrate the diversity of life on earth and wanted to send an invitation to each species, how many invitations would you need?
d. more than 1.5 million

4. And for ALL the species?
d. 8.7 million species

Some scientists have estimated that as many as 100 million species may actually exist, but this 8.7 million figure was recently published in the New York Times (actually it was 8.7 million +/- 1.3 million).

5. If we gave a prize for "the strongest creature for its size," which of the following would win?
c. ant

An ant can carry a load up to 50 times its body weight.

6. Which of the following environments on our planet are too harsh to support life?
e. none of the above

Amazingly, life has been discovered in all of these harsh environments. Newly identified microorganisms called "extremeophiles" thrive in unimaginable conditions, like boiling sulfur springs and polar ice fields.

Signs of Spring 1: Do You Remember the Color Green?

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I have had enough of winter. I have loved the snow storms and the cold nights and days. I have loved watching the continuing triumph of so many species over the stresses and trials of the winter season. Survival is always an epic saga!

But it is time for the awakening, a time for the return of green and growth. It is time to begin to once again appreciate the entirety of the biodiversity around us.

Roaring Run Trail near Edmon, PA in late February 2014Deborah and I went for a hike last Saturday afternoon in temperatures that were advertised to be 51 degrees (but felt like 41 when the sun went behind a cloud!).  We drove down to Edmon along the Kiski River and walked a seldom visited (by us anyway) part of the Roaring Run Trail. There was no one at the parking area and no one (and no fresh tracks) on the still snow-and-ice-covered trail.

 The path leaves the parking area and immediately drops down the long, steep Edmon Hill. Each step on the way made me think about the climb back! Not a very "Zen" way to hike at all. The sun arced past just over the top of the Kiski's western ridge. It generated enough heat to melt some of the ice underfoot and send ripples of water trickling down the slope. The surface ice on the river had a sheen of water on it, too, and expanding areas of melt-puddles that rippled in the fairly considerable wind. The smell of water was everywhere.
We saw a chipmunk sitting on top of a fallen log at the base of our eastern hillside. He noisily ducked back into the standing piles of brown leaves as we approached. Chipmunks are true hibernators. They enter into a physiological state of low metabolic activity, drastically slowed respiration rate, and depressed body temperature so that they can ride out the long, food-scarce months of winter. Chipmunks also gather and store in their burrows great quantities of food. These cached food stuffs must serve as energy buffers between their early spring arousal and the onset of true spring food production. Chipmunks also mate in the early spring (and again in the summer). So our observed chippie might have had lots of things on his mind!

We saw no birds along the trail. There were quite a few white-tailed deer tracks following the trail, but no other sign of any animals.

The wind blew hard down the eastern hillside and stirred up rolling clouds of dry leaves. The leaves rattled down the slope until they were caught behind downed logs and tight thickets of knotweed stems and raspberry canes. Each time the wind kicked up and a new cluster of leaves came tumbling down the slope we looked up thinking that something big was running down the hill toward us. Each time we were disappointed (or relieved).

We stopped at one of the benches near the little bridge that crosses Flat Run and ate some raisins and peanuts. We had walked not quite a mile, but the sun was dropping below the west ridge and the temperature was starting to fall. Also there was the long climb back up Edmon Hill that we had to accomplish. So, we finished our snack and headed back up to the car. This was not quite spring.

There are some things happening, though, that remind me that the seasons are changing. When I get up with our 6:30 am alarm I now can see what I am doing. The sun has begun to light up the early morning sky. When I drive home from work at 5:30 pm I don't absolutely need to have my car headlights on. The days are stretching out at both ends. Warmth is sure to follow!

There has been a subtle transition in my feeder bird community, too. The goldfinches are back and are emptying my thistle feeder every few days (a tube full of thistle lasted many weeks back in the deep winter). There seems to be fewer chickadees and juncos at the feeders but more song sparrows and house finches. Woodpeckers (red-bellied and downy) and northern flickers are in the yard (and pounding at the suet) much more regularly than they had been through the winter months. A few days ago I saw a bird pecking at the ground in the shadows of the arbor vitae and thought for a moment that it was a towhee (an iconic sign of spring for Deborah and I), but I was mistaken. Other than a couple of very confused looking robins perched up in surrounding maples, we have seen no arriving spring migrants yet.

We have seen small flocks of bluebirds swarming around the edges of the fields, and the local sharp-shinned hawk pair got quite friendly up in the tall black locust tree out back. I wish that I could put a camera beside the sharp-shin's nest so that I could see whether all of the action has generated any eggs. The bald eagle nest camera set up in Hays (near Pittsburgh's Southside) on a bluff over the Monongahela River is fantastic (and a great way to waste MANY hours of work time!). Check it out: There are three eggs in the nest and two very attentive parental eagles watching over and incubating them.

I had a question from a fellow Pittsburgh Eagle Cam viewer about how to tell the male and female bald eagles apart. The two genders have identical plummages, but the female is larger (up to 25% larger, in fact). This size dimorphism was also observed in our sharp-shinned hawks and holds for most species of hawks and eagles.

So, ignore the coming cold and snow. Spring is on its way!  

The Winter: Blue Jays

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Blue jay in a lilac bushWhy don't blue jays get any love and respect from birders? It would seem that a bird with such strikingly beautiful plumage would have a long list of admirers and devotees (photo by D. Sillman). Looking around some birding web sites I found the following descriptions of blue jays:

"noisy, bold and aggressive"

"a servant of the Devil"

"disliked by many people for their aggressive ways"

"disliked because they chase smaller birds away from feeders"

"they make harsh calls"

"Infamous as a destroyer of eggs and nestlings"

Now all of these things may occasionally be true (with the notable exception of "a servant of the Devil" (which refers to an old African-American folk tale)), but there are also times when they are each quite false.

This noisy, aggressive bird becomes quiet and nurturing around its nest (and nestlings). Also, mated blue jay pairs tend to be monogamous, and they stay mated for life. The female does all of the nest incubation and is devotedly fed during these long weeks by the male. Once hatched and fledged the young blue jays stay with their parents in a tight, cooperative familial group well into the fall. The blue jay's family values make most species look like barbarians!
Also, this "feeder dominating species" is itself often chased away from feeders by larger birds (like crows, red-bellied and red-headed woodpeckers, and common grackles). It may also be so intimidated by aggressive gray squirrels that it will not be able to utilize feeder resources at all. Further, the nest raiding behaviors that seem to dominate almost any ecological discussion of this species (see the last few sentences of the blue jay species page on the Virtual Nature Trail for an example) may not be entirely accurate. Recent studies of feeding behaviors and stomach content analysis of blue jays indicated that only 1% of the tested birds had any residue of eggs or nestlings in their stomachs.

 Maybe we all owe this species an apology?

Blue jays have a large throat pouch called the "gular pouch" in which they can store and transport seeds and nuts (especially acorns!). A blue jay's gular pouch can hold up to five acorns at a time! Further, blue jays are known to be very selective about the acorns they take. They pick up only the healthiest, least weevil-infested acorns (and therefore the acorns that are the most viable and most likely to germinate!). This ability to gather up acorns and fly them off to a safer location for solitary dining coupled with the blue jay's tendency to bury and store excess food makes them an active agent in acorn dispersal. It is suggested that the rapid spread of oak trees after the last ice age was due in large part to the energetic gathering and burying of the healthiest acorns by these very selective birds! On my own two acres in Armstrong County I have watched as oaks, brought in as acorns by blue jays from some distance away (twenty-four years ago when we moved here there were no oak trees within a half a mile of my house!) have germinated under the landscaping-planted spruces. These oak seedlings have in recent years grown through sapling stages into pole trees with heights well over twenty-five feet.

This winter I watched a blue jay out in my back yard take a peanut (which he had obtained from the front yard peanut feeder) and carefully, methodically sort through a thick mass of oak leaf litter (under a young red oak that the jay's great-great-great-grandfather might have planted!) until he found a perfect spot to hide the nut. He then dug a small hole in the leaf litter, inserted the peanut into the hole, and carefully covered the hole over with some of the displaced leaves. The blue jay spent ten minutes in his careful search and burial. He then flew up and perched on one of the lower red oak branches and surveyed his cache from above. Finally, and I could infer from his body movements that there was a great deal of hesitation inherent in this, he flew away (maybe to get another peanut?). I was almost sad when a few minutes later a gray squirrel dropped down to the ground under the red oak, went right to the peanut burial spot (had he been watching the jay from a higher branch of the tree?), dug up the peanut and ate it. I bet it was, though, delicious.

I would like to add a few words about the much maligned songs of the blue jay. They do have a harsh, rasping, throaty call (let's call this their everyday, "outdoor" voice), but they also have a wide range of both musical and innovative vocalizations including a pure tone whistle that regularly echoes across my fields and woodlots. Blue jays are also able to mimic the calls of red-tailed and red-shouldered hawks. There are many observations of blue jays using these calls to clear out a bird feeder so that they could then eat seed without annoying competition. Deborah and I once watched a blue jay up on a ridge over the Kiski River scream out red-tail hawk calls for no apparent benefit other than its own enjoyment. Last winter, on a snowy, cold, January morning, a blue jay in my street-side woodlot led me on a chase by making an American robin call from high up in the tree branches. I thought that I had an early sign of spring, but instead I was being tooled around by a musically creative blue jay!
In captivity blue jays, like their close, corvid relatives crows and ravens can be taught to imitate human speech and even make a variety of both animal-like and machine-like calls. Their intelligence, like the other corvids, is also quite impressive. They have even been described as making "tools" (folded pieces of newspaper) which they use to gather food from outside their cages.

Finally, I would like to talk about the courage that blue jays display. Blue jays are relatively slow flyers and are, therefore, quite vulnerable as prey for hawks and owls. Blue jays, though, respond to the presence of one of these birds of prey not in a cowering manner (which might increase the chances of survival of a given individual). Instead, blue jays become extremely loud (using their "outdoor" voice to great effect!) and agitated if a hawk or an owl has been spotted and form up in groups to harass and mob the intruder. Blue jays function as both the guard dogs and the security forces around the bird feeders they frequent to the great benefit of all of the other members of the feeder community.

So blue jays really aren't the thug-like birds of our stories. They display strong family values, work as foresters and security guards, can sing with the best of our song birds (although sometimes they choose not to), and they don't always eat their neighbor's eggs and babies.
What more can your ask of a neighbor? They are a species to be cherished, indeed!   

The Winter: Cold

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cold.jpgIn years when we have very cold, winter temperatures I often hear words of comfort from acquaintances: "These cold temperatures, at least, will kill the ticks and fleas!" and "The cold, at least, will kill the mosquitoes," and so on down a long list of arthropod pests. (Photo by D. Sillman)

I wanted to explore this idea since, as each of us must know by now, this year's winter has been a pretty cold one. The average temperature for Pittsburgh's January 2014 was 21.4 degrees F. This is the coldest average January temperature in many years but nowhere near our January of 1977 when the monthly average was 11.4 degrees F! At the other extreme, some of you may remember January 2006 when the monthly average was 38.3 degrees F! Very little snow that year!

So, how do over-wintering arthropods, especially insects and arachnids, handle very cold winter temperatures? Very well, apparently.

There are a number of very effective strategies that these insects and arachnids use to survive. Some avoid the cold either by finding natural hibernaculae (like insulated spaces in the soil or the protected cavities under the loose bark of trees).  Many species also enter human habitations (I bet that everyone reading this has lady bird beetles and stink bugs somewhere in their houses!). Insects can also alter their body fluids with chemicals that act like natural anti-freeze. These "supercooled" individuals ride out the cold temperatures in an apparently frozen, inactive state, but readily thaw out and regain full function when the temperatures moderate. Other insects synthesize special proteins (like the protein I mentioned last week in the "snow flea') that resist freezing. These proteins are concentrated in certain regions of the insect's body where they protect vital organs and allow less vulnerable parts of the organism to freeze.

Most insects and arachnids require temperatures of at least 50 degrees F for full activity, but all of the behavioral and physiological tools they can employ allow many of them to wait for those great sounding 50's to settle in with very little damage to their tissues or organs.
Most "endemic" species of arthropods (that is, those species that are native to this area and have evolved to survive in the changeable seasonal climates of our region) very easily survive both brutally cold winters and also the occasional cold snaps of spring. Sometimes the development of early season insect pests is slowed down by cold spring temperatures. These insects, then, lag behind their targeted spring plants because plants can continue to grow and develop at much colder temperatures than the insects. In this situation less damage to the spring plants is noticed. Endemic, summer-active insects, though, don't seem to be greatly affected in any way by prolonged winter cold periods or spring freezes (data from the Ohio Agriculture Research and Development Center).

Non-endemic arthropods, though, may be affected by our roller coaster weather patterns especially if those exotic, invasive species have come from areas where the evolutionary selection for suitable weather survival mechanisms has not occurred. Two invasive species that may be at least somewhat inhibited by cold weather are the emerald ash borer and the Hemlock wooly adelgid. Cold northern winters may also push the invasion line of the southern pine beetle (an endemic species of the southern United States that has spread into the north) further back to the south. Most ecologists, though, think that with the overall trend to warmer and warmer average global temperatures these occasional cold winter set-backs in the spread of these tree destroying pests are just transient victories in an on-going losing war.

So what about fleas? (And here I am talking about fleas that are ectoparasites of dogs and cats, not those wonderful, collembolan snow fleas). Cold temperatures (defined as temperature of 40 degrees or less) will kill adult fleas, but cold temperatures will not kill immature life stages of the fleas (larvae, nymphs, or eggs). So the adult fleas outside will die in the winter, but there will be significant numbers of the cold resistant immature life stages to repopulate the ecosystem and infest our pets once warm weather has returned. At least if there is a cold spring, though, the flea explosion might be delayed a bit, but it will eventually occur! An interesting but potentially unpleasant side note to this flea discussion concerns fleas that are living inside of our houses. The cold winter temperatures never do kill off the adults (not even if I would set my house thermostat down to 40 degrees!), and these fleas may stay active and continue to infest the resident dogs or cats all winter long.

Mosquitoes?   Same idea. Mosquitoes in their overwintering life stages don't seem to be affected by very cold winter temperatures. For some species of mosquitoes the overwintering life stage is a cold resistant egg, while for other species it is a larvae that lasts through the winter. There are even some mosquitoes in which mated adult females are the overwintering life stage. These adult females, when they emerge in the spring, are ready right away for a blood meal to enable them to lay their fertilized eggs. Again, cold spring temperatures may delay their emergence, but the cold does not seem to significantly reduce their numbers.

And finally, what about black-legged ticks (also called "deer ticks")? These are the arthropods that can transmit the bacterium that causes Lyme Disease, and these ticks for a variety of reasons (see August 24, 2013 blog for a discussion) have in recent years greatly increased in numbers throughout the eastern United States (including Western Pennsylvania). A study published in 2012 in the Journal of Medical Entomology clearly showed that in spite of "common knowledge" to the contrary, cold winters (and they used Upstate New York as their cold winter site!) do not reduce the numbers of overwintering black-legged ticks. The ticks just have too many adaptations for cold tolerance and too many protected microhabitats available for even the brutal winter temperatures of New York State to have any effect on them at all. Something very interesting to me personally about this tick study was the fact that these researchers used the same SUNY-ESF field lab site for their study that I used for my PhD research! Small world!

So, what is silver lining about having such a cold winter? Do we stay inside more and get more work done? Do we get to eat more high-calorie foods without significant weight gain? Or do we just appreciate the spring when it finally does come? I am personally anticipating a long bout of Spring Fever this year.