Signs of Spring 8: Mason Bees!

Photo by B. Moisset, Wikimedia Commons

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Mason bees (Osmia spp.) are solitary bees that have very short life spans (only six weeks or so). These bees nest in tubes or holes and have earned the name “mason” because they build wall-like partitions made of mud inside of their tubular nests. A mason bee gathers pollen and nectar from the flowers that are blooming during its short life and packs it around the eggs that it lays in the mud-wall partitions of its nest. A mason bee may fill up more than one nest with its eggs and its accumulated nectar and pollen.

The eggs then hatch into larvae that feed on the stored food and steadily grow and develop. The nest walls are extremely important here because they keep each larvae isolated with their own food supply! The mature larvae then spin cocoons and develop into pupae which will, still inside the cocoon, then molt into their adult forms. It is inside of this protective and insulating cocoon that the mason bee overwinters. In the spring, male mason bees emerge first and wait outside of the nest for the later emerging females. As the females emerge, the males immediately mate with them. After they mate, the males die, and the females then find a suitable tubular structure for its nest and begin to lay eggs, gather nectar and pollen, and, as a great ecological tie-in to this activity, pollinate many different species of flowering plants.

Photo by D. Sillman

Last Fall an old friend (and regular reader of this blog) gave me a beautiful, tear-drop shaped, bamboo basket of sealed up mason bee tubes. My instructions were to put it somewhere where it would stay cold all winter and to watch it carefully until Spring finally arrived. I hung the basket in my unheated garage and admired it regularly whenever I went down to get into my car.

The tubes remained quiet all winter, but suddenly, two weeks ago, they became active. A sticky, powdery dust layered out on my bicycle (which was parked right below the basket). Tiny holes showed up in some of the tube-sealing materials, and a small mason bee somehow flew up through the garage ceiling (maybe through the cold air return?) and ended up in my bedroom where I found him, immobile and, very sadly, deceased.

Outside our endless winter was still going on. Cold and snow and no flowers or nectar or pollen for the little bees. I had failed them and let them emerge too soon to survive.

Or so I thought!

Last Thursday it was sunny and 70 degrees. My forsythia along the driveway had started to flower a few days before. I opened my garage to work on my bicycle (a ride down on my local trail was actually possible that afternoon!). As I stood in the opening of the garage and let the sunshine pour in, I saw movement on the floor: mason bees!

The bees were exhibiting a vigorously positive phototropism and were moving slowly but steadily toward the sunlight. At first there were just a handful of them, and I gently picked each of them up and deposited them in the sunshine underneath the branches of the forsythia. Then there were more of them: ten, twenty, thirty, forty or more mason bees walking very zombie-like toward the sunshine.

Close up of mason bees in tubes

Photo by D. Sillman

When each bee got an inch or two into the sunny section of the garage floor they stopped as if stunned by how good the sunlight felt! They then wiggled their abdomens, groomed their wings with their legs, fluttered their wings and then, after two or three minutes of warming up and cleaning the garage dust off of their bodies, they launched themselves into the air. None of them flew very straight or with anything that resembled skill. They careened to the right or to the left and smacked into the wheel of my bike, or into my leg, or into the concrete block of the driveway wall. After they landed, though, they picked themselves up, readjusted their wings and then re-launched themselves into the air.

I watched at least twenty-five of the bees take their first flights. Often they would cycle back toward the garage before they finally found the forsythia. They frequently landed on my pant leg or on the top of my shoe before flight 2.0 ensued. Almost all of them, though, eventually ended up in the branches of the forsythia.

Photo by D. Sillman

I put the tube basket out in the sun next to the forsythia. As it warmed up I could hear scraping inside of the some of the still sealed tubes. A tiny flutter of powder began to float down in front of the basket. More bees were going to emerge! When I went back down to check on the basket after going up to my computer to write all of this down, there were active mason bees (the males) on the tube basket poking at the still sealed tubes. The scratching inside the tubes was even louder than before! The females were about to emerge!

An hour later the females were emerging from their tubes. The males were right there to mate with them and nature was taking its course!

I can’t tell you how much better I feel now that my mason bees survived my inept care! The very slow start to the spring made the timing of their emergence a very delicate thing. I am glad that they survived in the garage in their zombie-cold state, and I am very glad that the forsythia flowered in time to provide them a source of food. Survival is never guaranteed even with an abundance of clumsy human help: there are hungry birds waiting to pick off slow flying bees, there are old spider webs around the edges of the garage and up in the branches of the forsythia, and we had snow showers all day on Tuesday and today (Thursday) it is snowing again! There must be dozens of fatal traps lurking out there that could abruptly end this apian experiment.

The bees, though, are moving ahead as fast as they can! Here’s a video of them that Deborah made!

https://psu.box.com/s/nsz9nf6614n8zwpv65spd3ut1a7bjmm8

 

 

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Signs of Spring 7: Two Invasive Bugs

Photo by J. F. Orth, FLickr

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The spotted lanternfly (Lycorma delicatula) is one of the latest species in a long line of destructive, exotic insects that have invaded our agricultural and forested ecosystems. The lanternfly in spite its name is not a fly, nor is it, in spite of its often photographed spread-winged, moth-like appearance, a lepidopteran. It is a hemipteran (a true bug) with piercing, sucking mouthparts that is capable of doing great damage to a wide range of plants.

The lanternfly was first reported in Berk’s County in southeastern Pennsylvania in 2014. It is a native to China, India and Vietnam and is also a recent, and very destructive, invasive species in South Korea. It is thought to have initially entered Pennsylvania in 2012. In November 2014, the Pennsylvania Department of Agriculture established a quarantine of five townships in Berk’s County prohibiting the movement of firewood, lawn mowers, outdoor furniture, RV’s, wreaths, Christmas trees, etc. out of the area. This quarantine area has since been expanded to include a total of thirteen counties in the southeast corner of the state. The lanternfly is not a strong flyer and relies on human-aided transport to move significant distances, so this quarantine has been fairly effective in stopping the spread of this pest.

Photo by MTSOfan, Flcikr

Adult lanternflies are only 1 to 1 ¼ inches long and are fairly inconspicuous until they open their underwings to fly. The underwings are brightly colored (orange and red and white) and present a very distinctive, highly recognizable appearance. In the fall adult females lay eggs in grayish, mud-colored masses of 30 to 50 eggs that they attach to almost any solid object (including tree trunks and branches, outdoor furniture, rocks, etc.). The long list of objects enumerated in the quarantine regulations reflects the wide range of possible lanternfly egg deposition sites.

Eggs hatch in the spring, and the tiny nymphs (the first of four rapidly growing instars) find and feed on a wide variety of woody plants (including hardwood trees like willow, maple and poplar), pine trees, many types of fruit trees (including apple, plum, cherry and peach) and grape vines. The adults may continue to feed on this broad array of plant hosts but seem to prefer the exotic invasive tree called the tree-or-heaven (Ailanthus altissima) (see Signs of Fall 9, November 2, 2017). Large numbers of adult lantern flies and large numbers of egg masses can be found on tree-of-heaven, and proximity to tree-of-heaven in this quarantine area is major factor in the likelihood of finding lanternfly egg masses on surrounding objects.

Direct damage to the plants being fed upon by lanternflies can be severe, but even more extensive harm can be caused by secondary consequences associated with this initial feeding. Lanternflies feeding on a plant secrete a frothy substance called “honeydew.” The presence of this honeydew is often the way that a lanternfly infested plant is identified. This honeydew may attract other plant damaging insects and may also serve as the growth medium for some plant damaging fungi such as sooty mold.

Ongoing research at Penn State on these invasive hemipterans have involved genetic sequencing of the invasive population in order to determine the precise location from which they originated. Determining this location could then allow on-site evaluation of the native population to look for biological control agents like parasites, predators or parasitoids. The lanternfly’s microbiome is also being explored to look for potential pathogens or symbionts that may be useful in its control. The microbiomes of the plants on which the lanternfly feeds are also being evaluated to look for changes triggered by the lanternfly’s feeding and production of honeydew. The chemical ecology of the tree-of-heaven is also being examined to try to determine the exact nature of the lanternfly attraction and symbiosis.

Photo by D. Sillman

Another exotic invasive hemipteran that has been raising havoc in Pennsylvania is the brown, marmorated stink bug (Halyomorpha halys). These stink bugs are natives of northeast Asia (Japan, Korea, and China) and over the past twenty years have become a serious invasive pest throughout the United States. It is thought that this insect was first released into the United States in Allentown, PA in 1996. It apparently traveled from northeast Asia in a shipping container that was delivered either to the port of Philadelphia or Elizabeth, New Jersey and then trucked to Allentown. In 2001 this new, alien, invasive species was recognized and identified by entomologists at Cornell University, but by then large populations were being observed throughout eastern Pennsylvania, New Jersey and New York. This insect has now spread to forty states and is especially abundant in the eastern United States. It has very large populations in Pennsylvania, Maryland, Virginia, New York, New Jersey, Massachusetts, Delaware, Ohio, and North and South Carolina. Its spread to California and Oregon was allegedly via a car driven by a person traveling from Pennsylvania to California in 2005!

Many of these stink bugs find their way into our houses where they spend the winter months hibernating in tiny crevices and hideouts all around us. Their periodic emergence through the winter is often the only reminder that they are close by! Their mass emergence in May and June has become a very unfortunate sign of spring!

Brown marmorated stink bugs feed on over one hundred and fifty plant species including a number of crops that are of great economic importance to humans. Fruit trees (especially apple and pear), soybeans, and peanuts can all be significantly damaged by these insects. I have also seen adult stink bugs in my yard feeding avidly on the grapes growing on my grape vine.

Spider Eating Stink Bug  Photo by D. Sillman

I have talked in previous blogs about how local predators of insects (spiders and a variety of birds) have overcome their initial aversion to the protective secretions of these stink bugs and have begun to consume these slow moving bugs. Apparently, these emerging natural control systems in conjunction with increasingly sophisticated agricultural control regimes have reduced the overall impact of these pests considerably.

Dr. Greg Krawczk, a fruit tree entomologist and associate research professor in the Penn State College of Agricultural Sciences, says that the brown marmorated stink bug explosion peaked between 2010 and 2013 and that “we now know how to manage them.” In an October 25, 2017 article on the Penn State Newswire, Dr. Krawczk states that crop losses from these invasive bugs have been greatly reduced and that Penn State is exporting its knowledge and pest control technologies to many countries. For example, agricultural researchers from the Republic of Georgia are working with Dr. Krawczk and other scientists from Penn State, the USDA and Virginia Tech to develop programs to control their own recent explosions of brown marmorated stink bugs.

I hope the Georgian spiders and chickadee-equivalents learn how to feast on the bugs, too!

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Signs of Spring 6: Snail Kites and Rapid Evolution

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(Great thanks to Ty Bauman for permission to use several of his photographs in this week’s blog. Ty and his wife Linda have a bird/travel blog that is full of absolutely stunning pictures! I recommend it highly!)

Photo by T. Bauman

I have written about snail kites (formerly called the “Everglades snail kite”) (Rostrhamus sociabilis plubeas) before. They were one of the species that was hammered by Hurricane Irma when it hit the Florida peninsula last September (see Signs of Fall 7, October 19, 2017). All forty-eight of the snail kite nests around Lake Okeechobee were destroyed by Irma, and biologists were worried about the lasting impact of this reproductive disaster on this locally, very endangered sub-species.

But the snail kite had many more stresses prior to this latest hurricane. For example, this bird is a very specialized predator that feeds primarily on a single species of freshwater snail called the Florida apple snail (Pomacea paludosa). The importance of these snails to the snail kite is reflected in the very anatomy of the kite itself. The snail kite has evolved a highly specialized, sharp-pointed beak that is curved and aligned perfectly to allow it to pull the soft-bodied Florida apple snail out of its shell with great ease and efficiency. Now the snail kite does, at need, take and eat other prey items including crayfish and small fish, but apple snails are its overwhelmingly obligatory food of choice.

The snail kite also needs a very open vegetative habitat so that it easily locate the apple snails and then swoop down unimpeded and grab them at water level. They then take the captured snail to a perch to eat it.

There have been a number of impacts on the snail kite’s habitat that have interfered with both its food supply and its hunting strategies. Exotic snail species including the island apple snail (Pomacea maculata) have invaded the snail kites’ marshes and caused declines in the vital Florida apple snail. The island apple snails are two to five times larger than the Florida apple snail and are not as easily taken or de-shelled by a typical snail kite. Most of these invasive snail species are thought to have entered these Florida wetlands after being released by careless, tropical aquaria owners.

USGS, Public Domain

The Everglades is a vast, tropical wetland that once covered almost all of southern Florida. In wet seasons water flows slowly in a sixty mile wide front from Lake Okeechobee southward, down to Florida Bay. The flatness of the water surface hides the complex topography of the underlying, limestone bedrock. Small lifts or slight valleys in the bedrock can generate vastly different conditions for vegetative habitats. The open waters of the ponds over the deeper sections can transition into the wet prairies of slightly shallower sites, or the saw grass marshes, or the still only slightly drier “islands” of hardwood or pine forest in the shallower sections of wetland. This complex patchwork of wetland habitats supports and sustains a rich diversity of both plant and animal life.

Photo by Ty Bauman

The present day Everglades represents about half of its original area in southern Florida. Much of the primal wetland has been drained for agriculture and other human uses. Ongoing drought in Florida has also caused great loss of previously untouched wetlands and marshes. This shrinkage of essential habitat has greatly affected the snail kite. More insidiously, though, pollution from sewage and septic systems and nutrient runoff from agricultural fields has stimulated inappropriate plant growth and expansion of invasive plant species (like cattails and water hyacinths) throughout the remaining Everglades. This denser vegetative system makes the snail kite’s style of hunting less efficient and less productive.

In 2000 there were 3500 snail kites in Florida. By 2007 there were only 700 snail kites left. There was also a surge in the numbers of the larger, invasive island apple snail (coupled to a precipitous decline in the Florida apple snail) starting in 2004. Many scientists felt that this would be the final straw for the snail kites.

But they were wrong!

Photo by Ty Bauman

In the last ten years the population of snail kites has increased to 2000 birds. Further, these present day birds are different from the typical snail kite of a decade ago. In the past ten years the snail kites have gotten larger (on average 8% larger and at maximum 12% larger!) and their beaks have gotten bigger, too! Their larger body size and bigger beaks have enabled them to much more easily take and eat the larger island apple snails! Scientists like Robert Fletcher, Jr. of the University of Florida have been studying these changes in the snail kites and feel that they represent a classic example of Natural Selection at work. In the original population of snail kites there were some individuals that were larger than average. Those individuals (and their offspring) took advantage of the new abundance of the larger, exotic snails and fed extensively upon them. With each breeding cycle the larger kites had more food resources and produced more offspring, until the entire size profile of the population changed. That evolution could occur over such a short time period was surprising, but underlying logic of Nature Selection is compelling (Dr. Fletcher’s work is published in the November 27, 2017 issue of Nature, Ecology and Evolution).

We hope that the Irma-induced disruption of the snail kite’s breeding will not seriously sidetrack the recovery of its Florida population. Hurricanes are natural phenomena, and native species have persisted though a long history of these massive storms. The human generated stresses in the Everglades, though, may be more than what the native species can handle. That the snail kite has been able to re-model itself in the face of such a radical and rapid  transformation of its food supply is an incredibly hopeful sign. We wish the snail kite bon appetite and continued good escargot hunting!

 

 

 

 

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Signs of Spring 5: Skunks!

A close up of a skunk under a bird feeder

Photo by D. Sillman

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The scientific name of the striped skunk is Mephitis mephitis. “Mephitis” is Latin for “noxious vapor” and is an extremely appropriate genus and species name for this shy, unassuming member of  the mustelid (“weasel”) family of carnivores. The ability of the skunk to use its mercaptan rich musk as a defensive spray has been well represented in fiction and in the real life experiences of many people (not to mention their dogs).  The name “skunk” comes from the Algonquin name for the animal “seganku”. There are a number of less common, but often highly descriptive names for this animal including “polecat” and “infant du diable” (child of the devil) (a term of less than endearment from the early French Canadian trappers and voyageurs).

My son in law, Lee, just sent me a copy of the first historical mention of skunks. It is from an account of a Jesuit Priest in 1634:

“The other is a low animal, about the size of a little dog or cat. I mention it here, not on account of its excellence, but to make of it a symbol of sin. I have seen three or four of them. It has black fur, quite beautiful and shining; and has upon its back two perfectly white stripes, which join near the neck and tail, making an oval which adds greatly to their grace. The tail is bushy and well furnished with hair, like the tail of a Fox; it carries it curled back like that of a Squirrel. It is more white than black; and, at the first glance, you would say, especially when it walks, that it ought to be called Jupiter’s little dog. But it is so stinking, and casts so foul an odor, that it is unworthy of being called the dog of Pluto. No sewer ever smelled so bad. I would not have believed it if I had not smelled it myself. Your heart almost fails you when you approach the animal; two have been killed in our court, and several days afterward there was such a dreadful odor throughout our house that we could not endure it. I believe the sin smelled by Saint Catherine de Sienne must have had the same vile odor.”

Photo by D. Sillman

A couple of nights ago my dog, Izzy, found one of these “foul dogs of Pluto” out bumbling around under one of our bird feeders. The result was predictable although unfortunate. Deborah scooped Izzy up and deposited her into the bath tub while I mixed up a jug of hydrogen peroxide, baking soda and dish soap to scrub her with (here’s the recipe from the Humane Society website). The concoction worked well, and Izzy didn’t have to go sleep in the garage!  We’ll get the “dreadful odor throughout our house” cleared up eventually (I hope). I plan to research Saint Catherine de Sienne to see if she might have had some ideas that could help me with the clean up!

This is Izzy’s first skunk encounter. We installed a yard light out front to try to avoid unexpected night-time interactions like this. Our former dog, Kozmo, hated skunks with a deep passion and, as a result, got sprayed repeatedly. He would usually get hit the hardest in his open mouth as he was lunging at the skunk. Fortunately, I came across the de-skunking recipe about halfway through Kozmo’s skunk career. It works so much better than tomato juice! My good friend Steve Hoops (retired chemistry professor from Penn State) once explained to me how the hydrogen peroxide worked to shut off the volatile mercaptan and erase the stench of the skunk, but I forget the details. If he reads this post, maybe he will add the explanation in a comment!

No one who owns a dog has any reason to love skunks. They are, though, useful members of our suburban and rural ecosystems. They help to keep rodent populations under control, and they eat a variety of garden pests (including potato bugs and Japanese beetles) especially when they are in their larval (“grub”) stages.

Photo by D. Sillman

Skunks are omnivorous and will eat whatever is available. Seasonal foods include: in spring and summer, insects (both adult and larval forms) (especially grasshoppers, crickets, beetles, bees and wasps), spiders, toads, frogs, lizards, snakes, mice, chipmunks, turtle eggs and the eggs of ground nesting birds. In the fall and winter, they eat a variety of fruits (including wild grapes, and the fruits of wild vines like Virginia Creeper), carrion, and a many types of plants and plant  parts  (including grasses, leaves, buds) and nuts.  Skunks, like one Izzy met last night, also eat bird seed and may even rip into garbage bags and tip over trash cans.

The skunk is a slow, deliberate creature that is capable under extreme need of a clumsy gallop that can  reach up to 10 mph. It is a very poor climber but is capable of swimming. Its sense of sight, smell and hearing are poor but it is reported to have a very acute sense of touch. It is a nocturnal animal typically becoming active just before sunset and then inactive just prior to sunrise.   During this night-time activity period it typically takes a single rest period of one to two hours usually away from its sleeping den.

Photo by D. Sillman

Skunks by common account are not very intelligent animals. They display, though, good problem solving behaviors to acquire food. They have been described as scratching on the outside of a bee hive to induce the bees to fly out to investigate the noise and intrusion. The skunk then catches and eats the bees as they emerge. Skunks also eat tenebrionid beetles (“stink beetles”) by taking the large beetle in their front paws and rolling it around in the soil until it has exhausted its reserve of irritating, quinone spray. The skunk then is able to eat the beetle without the unpleasantness of the quinones.

Skunks are solitary creatures except during a very brief mating period in late winter or early spring. Adult  males are very active during this mating season and travel widely in search of a receptive mate. During this courtship and mating period large numbers of skunks end up as roadkill on our roads and highways. Males fight each other over females during this courtship and mating period, too. It is interesting, though, that in these aggressive conflicts the males do not utilize their musk as offensive weapons.

Photo by D. Sillman

Last night, two nights after Izzy’s skunk encounter, Deborah and I watched a skunk (probably THE skunk) amble slowly across our field just before sunset and work his/her way to our front yard and the bird feeders. The pictures in this post are all from that encounter. It was interesting to watch a skunk that closely! He/she did not seem at all anxious about returning to the place of its Izzy-interactions.  It is useful in Nature not to dwell on unpleasant or frightening events! I just hope that he/she is not planning to den up under my new sun porch!

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Signs of Spring 4: Wood Frog Day (year #6)!

Photo by D. Sillman

(if you would like to listen to an audio version of this blog, please click here!)

I am sitting at my writing desk on this first day of Spring watching the snow pile up in my back yard. It is very difficult to keep track of what should be happening as winter fades away, but I don’t think that five inches of snow is at all normal. But is it unexpected?

We live in a climate zone that is subject to all sorts of swings and shifts in weather. Some of these shifts actually occur with some regularity and are referred to as “weather singularities.” We even have common names for some of these weather twists and turns. In the Fall, for example, after the first frost and the initial onset of cold temperatures, the weather often moderates and the days become warm and hazy. We refer to this singularity as “Indian summer.” Also, almost every January we have a stretch of days or even a week when temperatures climb above freezing sometimes all the way into the 50’s or 60’s F and the air starts smelling like Spring. We all think “this is unusual!” but, actually, it is typical. We call this weather singularity the “January thaw” (what an incredibly logical name!). We also get snows in late March or early April and think, “how strange,” but actually we regularly get these late snows. Here in Pennsylvania we call this weather singularity an “onion snow” because it occurs along with the sprouting of the spring planted onions out in our gardens.

We each have very hardwired ideas about our climate and about what the weather should be at any particular time of the year. When the weather we observe differs from our mental models we feel that there is something odd going on around us, something strange. It is very difficult to keep a mental track of the 365 days of each year, year in and year out!

Cliff swallow. Photo by I. Taylor, Flickr

The habits and movements of animals help us focus on a particular year and compare it to our previous experiences. Migrating cliff swallows in California don’t always return to San Juan Capistrano on March 19, but their return a week before or a few days after is a good index on what kind of year (weather-wise) it has been! The turkey vultures don’t always return to Hinckley, Ohio on March 15, but their earlier or later arrival helps us to focus on the features of the winter to spring transition that we are experiencing.

There are many celebrations of the return of migrating birds all around the world. In Ketchikan, Alaska they watch for (and celebrate) the return of the Rufous Hummingbird. Aborigines in Australia celebrate the return of the migrating sand pipers (or some would say via their dances and rituals they actually call the sand pipers to them!) in order to mark the onset of the wet season with its life-giving and sustaining rains.

Phenology is the scientific study of these cyclic patterns of animals and plants. A phenologist might observe the return of some migratory species or the emergence of some hibernating animals. They might observe the timing of the flowering or leafing out of certain plants. They might observe the activity of certain insects. You can imagine all of the phenological data collected feeding into an intricate matrix of a vast number of variables which then generates a mathematical function that clicks its way through the ecological events of each and every year. Phenology is a very precise way to make year to year comparisons of seasonal transitions and phenomena.

And, that’s why we have invented “Wood Frog Day!”

Photo by B. Gratwicke, Wikimedia Commons

Some background: The wood frog (Lithobates sylvaticus)(formerly Rana sylvatica) is found from northern Georgia all the way up to the Arctic Circle. In fact, it is the only “cold blooded” vertebrate known to live north of the Arctic Circle! They utilize temporary pools formed by spring rains and snow melt as breeding pools and then spend most of the rest of their active season away from standing water. Wood frogs spend the winter hibernating in a frozen state deep in the litter and soil near their vernal pools and emerge en mass in the spring to mate. For the last six years, Deborah and I and Rob and Michele Bridges have gone down to Ohiopyle, Pennsylvania in mid-March to check on these glorious frogs. Our phenological observations on these animals and their surrounding ecosystems have given us some insights into our pulsating climate and the differences between each of the passing years. Each date, by the way, is a link to the original blog post about the “frog walk!”

Photo by D. Sillman

March 16, 2013: Coltsfoot is blooming in sunny spots along the Youghiogheny River. Comma butterflies are flying about up in the rhododendron thickets. Wood frogs are abundant (and croaking loudly!) in the vernal pools along the upper hiking trails.

March 14, 2015: No coltsfoot blooming yet. No butterflies. Water in the Youghiogheny is very high. Pools along river don’t have any frogs or insects. Wood frogs are active in the vernal pools along the Great Allegheny Passage Trail and around the parking lot of the trail. Frogs are catapulting themselves out of their soil and leaf litter hibernaculae into the active

Photo by D. Sillman

pools. Lots of frog “quacking” and mating!

March 19, 2016: Low water levels on the Youghiogheny (a very dry winter and spring!). Pools along Yough, though, are full of tadpoles, and egg masses and adult wood frogs. A salamander is seen in the Yough pools and water striders are abundant. Wildflowers blooming along upper trails (red trillium, sessile leafed bellwort, star chickweed). Red maples and Yellow poplars just starting to leaf out. Pools up along Great Allegheny Passage Trail are very shallow and full of litter and debris (no frogs or tadpoles or eggs seen).

Photo by D. Sillman

March 18, 2017: Very little winter snow and a very dry spring. Coltsfoot blooming. Pools along Yough are alive with wood frogs (large females and smaller males all actively quacking). Large egg masses. An eastern newt is seen in one pool. No other wild flowers along upper trails. No wood frogs in pools along Great Allegheny Passage Trail. Pools are very shallow and full of trash and debris.

March 18, 2018: It has been a cold spring but there has been abundant winter snow and lots of recent rain. We were hopeful that there would be water in the vernal pools down at Ohiopyle. It was sunny and in the upper 40’s when we headed out on

Photo by D. Sillman

our hike. No coltsfoot blooming yet, no other spring wildflowers. No butterflies. The pools along the Yough are partially covered with slushy snow. There are ring shaped markings in this pool snow (each ring is about 2 inches in diameter). The rings are very regular and very abundant. Possibly they are formed by decomposition gases (carbon dioxide? methane?) rising up from the warming sediments of the pools? The covering ice is slushy enough to be shaped by the rising  gases, but solid enough to hold the new shapes? There are no frogs, no egg masses, no tadpoles in the Yough pools. No salamanders. No water striders. One adult caddisfly was seen next to one of the pools. The upper trail pools along the Great Allegheny Passage Trail are very shallow in spite of all of the rain and snow melt. They are clogged with debris and look as though they have been used as branch and log disposal sites. No frogs at all.

Our Wood Frog Days have not always had any wood frogs, but they give a point of time focus for the onset of Spring. We do see that the mating pools on the rocks along the Youghiogheny River have become very important for these wood frogs and that the pools up along the Great Allegheny Passage have been degraded by human activity and neglect. These upper trail pools are being drained too rapidly to be useful to the frogs and are being used as wood and debris disposal sites.

 

 

 

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Signs of Spring 3: The Evolution of Butterflies and Moths

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(Thanks to Rob Bridges who passed along a newspaper article about these very interesting moth and butterfly fossils.)

Mourning cloak. Photo by D.G.E.Robertson, Wikimedia Commons

Butterflies and moths are collectively called the “lepidoptera” (“the scaly wings”), and they are very important signs of many of our seasons. In the early spring, mourning cloak butterflies emerge from their tree bark, hibernation crevices on those first, almost warm, sunny days of early March and flutter about sometimes over the still standing snow cover looking for potential mates. Then, in the late summer and early fall, monarchs migrate across our area (sadly, only in a hint of their formerly massive numbers). We see them first as they fly though on their ways to the northern edges of their summer breeding regions, and then again, later in the season, as their offspring fly back south toward their overwintering forests in the mountains of Mexico.

In between these spectacular seasonal bookends there is a glorious diversity of swallowtails, fritillaries, commas, sulfurs, skippers, sphinxes, lunas, and cecropias. Worldwide there are 160,000 species of moths (12,00 in North America) and 17,500 species of butterflies (760 in North America). Websites devoted to Pennsylvania moths and butterflies, though, usually only describe the 140 or so most common (or most abundant) species.  There is much more to these beautiful insects, though, than meets the untrained eye!

The life cycle of a lepidopteran is familiar to almost everyone: the early life stages (the larvae) are soft-bodied caterpillars that voraciously feed on plant leaves or other cellulose sources. The later life stages (the adults) are the actual winged moth or butterfly. These adults use their coiled, tubular mouthparts (called “proboscises”) to feed on fluids especially the sucrose-rich nectars generated by flowering plants. Each flower makes a very small amount of nectar, so butterflies and moths have to visit many flowers in order to get enough to eat.  As they make their trips from flower to flower they inadvertently pick up and transport pollen (a protein encased package of flower sperm) from one flower to another and, thus, fertilize the ova in each visited flower.

Hummingbird moth feeding. Photo by T.Hisgatt, Wikimedia Commons

Many elaborate flower anatomies are matched by lepidopteran proboscis structures, and it has been widely assumed that the present day anatomy of lepidopteran mouthparts is the consequence of their direct coevolution with flowering plants. The first flowers show up in the fossil record about 130 million years ago (MA). There are some controversial “flower fossils” dated to 162 MA, so a conservative date of origin of flowering plants is somewhere around 150 MA. Most previous studies suggest that moths evolved around 130 MA and butterflies significantly later (around 56 MA), so these time frames fit well into the plant/lepidopteran coevolutionary model.

Recent findings, though, challenge this very clear and very logical evolutionary explanation!

Fossils of moths and butterflies are not very abundant. Possibly this is because these insects are not common in habitats (like ponds and lakes) in which fossils most easily form, or possibly it is because their delicate bodies are not readily conserved in fossilized forms. One aspect of the lepidoptera, though, that is tough and resistant and readily fossilized are their wing scales, and this is what a team of German and American scientists found in some sedimentary rock cores from northern Germany that they were examining for fossilized plant pollen.

SEM of butterfly wing scale (x1000). Photo by SecretDisc, Wikimedia Commons

A diverse array of lepidopteran wing scales (suggesting a variety of species) were found in rock cores that date back to 200 MA! This is at least 50 million years before the evolution of flowers! So, the compelling question is, what were these ancient, fluid feeding moths living on if there were no flowers? (the research team’s findings are published in the January 10, 2018 issue of Science Advances).

Observation of present day moths and butterflies suggest some possible food sources for these “pre-flower” moths. Tree saps, for example,  are a potentially sugar-rich food stuff that is utilized by both butterflies and moths as a supplemental food in their nectar-dominated diets. Coniferous trees originated some 300 MA and were the dominant land plant of the Mesozoic Era. Breaks in the bark encasements of these conifers could have provided the first lepidopteran species with a sufficiently rich and reliable food supply to sustain them and could also have favored the evolution of tubular proboscises in these early moths. These tubular mouthparts, then, represent a pre-adaptation for subsequent use 50 million years later when flowers and their nectar food supplies came into being. Possibly, the mouthparts of the lepidopterans stimulated the anatomical evolution of flowers rather than vice-versa! The evolution of flowers, though, stimulated extensive speciation in moths and eventually led to the evolution of butterflies.

Comma butterfly. S. KIng, National Park Service

We will see the first mourning cloaks very soon. Then, on some sunny mid-March day, we will see the bright orange, comma butterfly (Polygonia spp.). The comma, like the mourning cloak, can overwinter as an adult and can thus take advantage of warm spring afternoons to feed on early nectars and get an early start on their spring reproduction. Often in late March we also see the tiny (1 inch across) spring azures. These stunningly beautiful butterflies have neon blue dorsal wing surfaces that seem to glow as they fly about. When they land, though, and close their wings, the blue color (and to all appearances, the butterfly itself!) disappears as the pale white under-wing coloration blends in to the surrounding browns and grays of the early spring vegetation. The spring azure overwinters as a chrysalis and finishes its metamorphosis into an adult even while snow still covers the ground.

The number and diversity of butterflies and moths will rise exponentially when we get into April and May. They are organisms that have been around 200 million years, and they still fill their ecosystems with grace and style!

 

 

 

 

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Signs of Spring 2: Two Walks

Photo by D. Sillman

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Deborah and I went down to the Rock Furnace trail last Sunday afternoon. There was abundant sunshine, but the air was shockingly cold when you stepped into the shade. The wind was also steadily blowing at 10 to 15 mph, so the shelter of the ravine through which the trail runs, in spite of its shade, was most welcome. There were only a couple of other people out on the trail, so it was a quiet, peaceful walk.

Sounds of rushing water surrounded us. Down below, in its narrow channel, Roaring Run cascaded along over room-sized rocks and joined the smaller Rattling Run at the old, concrete bridge deep in the hollow. Rattling Run had come in via its picturesque drop over Jackson’s Falls just a quarter of a mile or so up a side-trail that is now marked “private property.” The abundance of rain last month (over eleven inches!) had filled the springs and all of the flowing channels. Gravity, then, was pulling all of the water towards the big rivers!

Photo by D. Sillman

Back in the early Nineteenth Century there had been a tavern and a couple of cabins here in this hollow. There is an old, stone-lined well just off the trail and a bit further down the stream there are piles of tumbled rocks that had once been a functioning iron furnace. Trees on the surrounding hillsides were repeatedly cut to make charcoal, and limestone and iron-bearing sandstone were tumbled and carted down the surrounding slopes to feed the furnace. The resulting pig iron was taken a mile further down Roaring Run to the Main Line Canal and then barged down to forges and mills in Pittsburgh.

This furnace, like most of the scattered furnaces throughout the East, had a very short functional life. It quickly exhausted its ore and wood resources and was eventually replaced by more efficient systems.

Photo by D. Sillman

Everything is dully colored down here. The forest floor is littered with dry, brown leaves, and the gray tree trunks (mostly red maple, yellow poplar and beech) stand in dense copses, incredibly uniformly sized (6 to 8 inches dbh) all along the trail. These trees are recovery relics from the wholesale cutting  needed to feed the old furnaces. There is a stand of eastern hemlocks along the stream that may be a remnant of the hemlock forest that would have dominated this cool, wet ravine before the iron furnace was set up. Out in the surrounding acres of hardwood trees, occasionally a small hemlock can be found growing all by itself. These small trees are probably surprisingly old! If they get three or four hundred more years, each of these hemlocks will be centers of ecological “crystals” that will merge into a new hemlock forest. All of these maples and poplars,then, will just be distant memories in the humus.

Photo by D. Sillman

It’s easy to spot the hemlocks. They are bright stabs of green in the brown and gray of the forest. Looking closer you can see other patches of green, too. Evergreen wood fern and Christmas fern, and polypody fern up on the sandstone boulders have kept their chlorophyll all winter. Also, many of the rocks and some of the fallen logs and stumps have moss growing on them. Many of these moss mats have recently sent up sporophyte stalks (they are so new that they are still green!). The knobby capsules on the tips of the stalks will make spores that will disperse in the wind or in the rain and let the moss mat slowly increase its density and steadily expand its edges.

There are no spring wildflowers yet. No colt’s foot even at south facing hillside beside the McCartney #6 gas well. This is the spot where the first blooms are usually seen. No spring beauty, either. There are a few isolated clumps of grass left over from last year’s growing season. The water in the shallow drainage ditches is cold and quiet, too. No insects or amphibian eggs or tadpoles. Nothing new for this year, at least not in the view of our weak human senses.

(The next day Deborah and I headed up to Harrison Hills Park)

It was, once again, sunny but cold (only 38 degrees when we started). Much less wind today, though, which we greatly appreciated since we would be walking out in the high, open meadows of the park. We were here to check our bluebird boxes and make sure that they were ready for the coming nesting season.

We parked at the Environmental Learning Center and walked down the service road, past the still covered purple martin houses. We were alert for any sign or sound of early arriving field sparrows and also watched for any bluebirds that might have overwintered, but we saw neither.

Photo by D. Sillman

The sunlight was intense and was playing tricks on us. The tall yellow poplar trees on the edges of the purple martin field and along the access road were covered with their old, brown, cone-shaped clusters of samaras making the outline of their crowns quite distinct from any of the other types of surrounding trees. The sunlight, though, reflecting off many of these samara “cones” made them look bright white, and the intensity of the color made these old, dry outlines of flowers look new and fresh! I had to mentally walk through my sylviculture to reassure myself that, no, these trees were not in early flower. We would have to wait for mid-April (when the poplar trees were all leafed out) for the colorful flowers of these “tulip trees” to open up.

A vulture flew overhead wobbling in the rising thermals. The sun reflected brightly off of its bald head, though, making it look white, too. For a few seconds, in spite of the uplifted wings (shaped into a “V” (for vulture!)) and uncertain flying pattern we thought we were looking at a bald eagle.

Photo by D. Sillman

Our bluebird boxes looked good. A few of them had obviously had some overwintering occupants. We cleaned out some dried fecal pellets and even found a few bright blue feathers. The non-migrating male bluebirds must have packed into these boxes for communal shelter and warmth during the winter months.

Up in the High Meadow (the field where most of Deborah’s and my assigned boxes were located) we made a surprising discovery. On the north edge of the field, tucked into some bushes, there was a nesting box that we hadn’t noticed before! Three years ago our volunteer group took over the park’s set of nesting boxes that had been built and set up by a Boy Scout troop in 2005. We inventoried all of the boxes, repaired many of them, and assigned them numbers. We have had three years of remarkable success with bluebird nesting! This box, though, had been missed!

I could not open the box (the locking nail was tightly fixed) but could see via the entrance hole that it was packed full of nesting materials. I slipped it off of its pole and brought it home to clean it out and make some repairs. When I opened the box down in my garage I found that it was packed full with a pound or two of soil and leaves and small sticks. It was a nest construction that I had not seen before! I used a putty knife to loosen the edges of the nesting mass. As soon as I inserted the knife blade a very energized, white-footed mouse shot straight up out of the nesting box and hit the floor of my garage running. He raced under a stack of old two-by-fours and was gone.

At least I know what kind of a nest it was! I wish that my cat, Mazie, had been there to help me with that mouse!

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Signs of Spring 1: City Deer and Country Deer

Photo by D. Sillman

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Back in 2010 Deborah and I hiked the length of the Baker Trail here in Western Pennsylvania. The Baker Trail is by most accounts 132 miles long (although the mileage varies depending on which source you consult). We did the hike in 8 or 9 mile segments and made note of the trees, plants, and animals that we saw along the way. I have written about this hike on my Western Pennsylvania hiking web site (“Between Stones and Trees”) and also in an article for the Pittsburgh Post-Gazette. I also have a detailed narrative of the trail from its start at the Freeport Bridge all the way to its terminus in the Allegheny Forest that is available upon request (if anyone wants to know the specifics of some particular section of the trail).

We saw many things on our hike and put together some interesting hypothesis about the historical ecology of Western Pennsylvania. We also made some interesting observations on the ecology and possible ongoing evolution of some of the animals we saw on the trail. I have told my students that asking yourself “did I really see that?” is an excellent way to get started in the process of science! One of our “did we really see that?” speculations from our weeks on the Baker Trail concerned the white-tailed deer (Odocoileus virginianus).

In 1900 it was estimated that there were only 500,000 white-tailed deer left in North America. Intense hunting pressures and massive deforestation through the Nineteenth Century had decimated their numbers and made them a species only rarely seen in our forests. The sighting of a deer, in fact, could make front page news in some of the rural newspapers of northwestern Pennsylvania! Today, however, there are estimated to be over 15,000,000 white-tailed deer in North America! Forest regeneration, elimination of natural predators, and strict hunting laws have allowed this species to reach population numbers and densities that far exceed those even of the pre-European settlement forest ecosystems!

USDA Photo, Public Domain

White-tailed deer are both a charismatic species of our eastern forests and a major problem. The sight of a deer emerging from a stand of trees or brush is breathtakingly beautiful, but the damage they do to tree seedlings and forest understory plants (not to mention gardens, shrubs and ornamentals) is devastating. Some foresters, in fact, refer to white-tailed deer as “tree locusts,” and forest ecologists worry that the consequences of deer browsing on tree seedlings might include the disruption of forest succession and renewal throughout the northeast! Fern-lands and moor-lands could possibly replace our diverse hardwood forests if deer are allowed to consume the next successional generation of trees!

But let’s get back to our observations of white-tailed deer. The Baker Trail takes a hiker through a wide range of habitats and landscapes. You walk through suburban neighborhoods, down country roads, through farms and around fields, through old industrial and mining sites, and also through some almost pristine forest. You see the whole range of what is possible in Western Pennsylvania (with the exception of, say, the city canyons of downtown Pittsburgh). In almost every one of the habitats and landscapes we walked through we saw white-tailed deer. The deer in these different places, though, were not at all the same.

In suburban neighborhoods it seemed to us that the deer were larger, and that the does almost always had twin fawns with them.   These “city” deer were also much less concerned with us as potential threats or predators. Their “flight initiation distances” (FID’s) were greatly reduced, and they allowed us to walk up quite closely to them!

In the most “natural” of our hiking habitats, though, we felt that we saw a very different type of deer. The adults seemed smaller than their “city” counterparts, and the does seemed to almost always have only one fawn. Further, these “country” deer did not tolerate us to approach very closely. Their FID’s, then, were quite large, and they were very alert and quite wary.

Over these past few years I have frequently looked through some of scientific literature that discusses deer behavior to see if anyone else has had these kinds of observations or impressions, and I think that I have finally found a few.

For example, a study at Georgia Gwinnett College found that “urban” deer were larger and better fed than their more “rural” counterparts. The diversity and abundance of often non-native landscaping plants in the suburban ecosystem provided the deer with a diet that was richer in calories and possibly even richer in nutrients than the wild foods of the surrounding rural ecosystems. Further, they noted that these “city” deer were protected from both natural predators and also human hunters.

Photo by D. Sillman

A study in Minnesota (in the city of Minnetonka) indicated that “city” deer have a very high survival rate and that ‘city” does have a 93% pregnancy rate typically with twin and even triplet fawns.

In Indiana a study as part of a Master’s thesis at Ball State (T. Carter 2016) measured fawn survival rates to 32 weeks of 70% in urban areas (primary cause of fawn deaths were cars) but only 44% in rural areas (primary cause of fawn deaths were coyotes).

In  Massachusetts Gaughan and DeStefano found that urban deer had ranges that were one tenth of those of rural deer, indicating a much higher quality of habitat and, possibly, a reduced probability of chance encounters with either cars or predators (their paper published in Urban Ecosystems in 2005).

Urban and suburban environments, then, greatly favor the growth, survival and reproductive success of white-tailed deer. The deer are bigger (due to more and, possibly better quality food, and also due to the reduction of stress and the necessity of giving up feeding time to watch for or run away from potential threats). The fawn survival rate is higher due to an absence of predators (this was probably why it seemed that all of our “city” deer on the Baker Trail had twins!). A “city” white-tailed deer, then seems like a different animal than its “rural” counterpart!

One last piece of information from the literature: In his book Urban Wildlife Management (3rd edition, 2016) Clark Adams cites a 2011 United Nations study that indicates that 82% of the white-tailed deer in the United States live in urban areas. I have not been able to find this study to read it for myself, but, if true, this is a remarkable statistic that, I think, shows that white-tailed deer are becoming primarily an urban species. It is evolution occurring right before our eyes!

 

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Signs of Winter 12: Bacteria, Anxiety, Sponges, Flies and Chicken Eggs

Photo by AJC1, Flickr

If you would like to listen to this blog rather than reading it , please click on this link!

The numbers that describe the human microbiome are overwhelming. There are between three and ten times more bacterial cells in and on “you’ (and in and on every other person, too) than there are cells of all of your tissues and organs. These bacteria help the body to resist infections by pathogens from the environment, assist in the digestion and absorption of food, synthesize a number of vitamins, and produce a number of hormones that modulate and coordinate the organ systems of the body (including the immune system!). Many aspects of our individual microbiomes are established at birth (especially our gut microbiomes), but the growing science of probiotics indicates that vital microbial systems can be modified by diet.

In a recent paper published in Molecular Psychiatry (May 16, 2017) researchers at the University College Cork in Ireland found that fear is influenced by a organism’s gut microorganisms. Comparing bacteria-free mice to mice with normal gut microflora, they found that the bacteria-free mice had reduced fear responses to stressful stimuli. This study correlates well with work published more than a decade ago by researchers at Kyushu University in Japan that showed that gut bacteria can modulate stress responses through vagus nerve influences and also other mechanisms.

Work at UCLA (published in Gastroenterology in 2013) showed that the ingestion of a probiotic yogurt twice a day for four weeks led to a reduced brain response (as measured by functional MRI’s) to negative images.

A number of these researchers are hopeful that diet and microflora manipulation may become a tool for clinicians to treat fear and anxiety-based syndromes including post-traumatic stress!

Photo by Pierie, Wikimedia Commons

Our environments contain many bacteria, too, and many of these come into contact with us via some expected and also some unexpected routes. Most of these environmental bacteria are quite harmless, but some are powerful human pathogens.  Think of the sponge you use in your kitchen, for example. Sponges are ideal bacterial habitats, and, as they are used to wipe up messes and clean surfaces, they get infused with a rich diversity and abundance of bacteria. In a paper published in Scientific Reports this past summer (July 19, 2017) a research team at the University of Furtwangen in Germany identified 362 species of bacteria living in a kitchen sponge at densities of 82 billion bacteria per cubic inch of sponge! Typical methods of disinfecting a sponge (microwaving it, washing it in the dishwasher or laundry, soaking it in vinegar or other cleaning solutions, or cooking it in hot water) do initially reduce the overall numbers of bacteria, but they also select for some of the most pathogenically dangerous species in the sponge microbial system!

“When people at home try to clean their sponges,” stated the lead researcher on the project,” they make it worse.”

What should you do with your kitchen sponge? It quickly becomes a dispersal agent for bacteria and the more you try to clean it, the more pathogenic it becomes! The researchers recommend that you either throw the sponge away and replace it with a new one every week or so, or disinfect it and then use in some other house location where food is not handled (like a bathroom or a basement).

Photo by USDA, Wikimedia Commons

Organisms around us also have microbiomes and many of these come into contact with us. A paper published this fall in Scientific Reports (November 24, 2017) by a group of scientists at Penn State and Nanyang Technical University of Singapore precisely quantified the surface bacterial populations on the bodies, wings and feet of houseflies (Musca domestica) and blowflies (Chrysomya megacephala).  The hundreds of bacterial species carried by these flies include many human pathogens. These researchers also determined that when one of these flies lands on a surface, they leave behind in their footprints potential bacterial colonies that can, depending on the receptivity of the surface, grow into significant inoculates. Included in the human pathogens transported by these flies was Helicobacter pylori, the bacterium that can cause stomach ulcers in humans. Fly transmission of H. pylori was unknown before this study and was not included in the epidemiological models of H. pylori dispersion. Interestingly, this study also found that flies collected in urban environments tend to carry more pathogenic bacteria than flies collected in rural environments. Even the proximity of stables and barns did not bring the pathogenic bacteria loads on the flies up to “city” levels!

(I guess we know where to have our picnics this summer!)

And, finally, I come to some observations from the Science section of the New York Times that I have been trying to work into a blog for almost a year!  The topic is the bacterial microbiome of a chicken egg.

Photo by tiffanykay, PIxabay

A Times reader wrote in to ask “why do Americans refrigerate their eggs?” making the observation that in Europe and many Asian countries eggs are kept in bowls out on the kitchen counter (February 13, 2017). The answer has to do with the microbial and protein components of the egg shell’s surface. In the United States large egg producing facilities (defined as those that have more than 3000 hens) are required to wash their eggs before they can be sold to consumers. The reason is the bacterium, Salmonella. Salmonella is quite common in the digestive and reproductive tracts of chickens, and the bacterium can get incorporated into the forming egg in the chicken’s ovary or smeared on the outside of the egg shell from the chicken’s feces. The Center for Disease Control (CDC) estimates that there are 1.2 million cases of Salmonella food poisoning each year in the United States and 450 resulting deaths. While eggs are not the only source of Salmonella, they are a very controllable one.

So in the Unites States most commercially produced eggs are washed. This washing does remove the surface Salmonella, but it also removes a thin, protective coating that seals and waterproofs the egg. The lack of this coating means that the egg will lose its internal moisture much more rapidly and allow environmental bacteria to much more easily cross into the egg. Both of these consequences greatly reduce the shelf-life of an egg unless, of course, it is refrigerated.

The European Union, though, prohibits the washing of commercially produced eggs. They feel that the potential benefit gained by the removal of Salmonella does not justify the loss of egg freshness and quality caused by the washing away of the protective egg shell seal. It would be interesting to see if there are more (or fewer) cases of Salmonella poisoning in Europe compared to the United States.

So, bacteria are in us, around us, and moving through us. Wash your hands and enjoy your eggs!

 

 

 

 

 

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Signs of Winter 11: The Great Backyard Bird Count

Photo by rhaij, Pixabay

If you would like to listen to this blog rather than reading it, please click on this link.

Starting tomorrow (February 16th) and running until Monday (February 19) the Cornell Laboratory of Ornithology, Birds Studies Canada and the National Audubon Society are sponsoring their annual “citizen’s science” project called “The Great Backyard Bird Count” (GBBC). This world wide count of birds began in 1998 and has grown in scope and participation with each passing year. Participants are asked to spend fifteen minutes either stationary at some observation point or walking through a habitat counting and identifying the birds they see. On-line checklists developed by eBird facilitate the reporting of these observations, and the compilation of the data from the observers seems to be nearly instantaneous!

If you are interested in participating in the count click here for more information!

Some highlights of last year’s count (found on the GBBC web site) include the total number of checklists submitted (181,643) and the total number of people submitting one or more checklist (210,000). A total of 6,261 species of birds were identified and 29,604,680 birds were counted! This was, indeed, a very robust survey of birds!

Photo by D. Sillman

There was a distinct North America bias to last year’s count as 62% of the checklists came from the United States. The ten most frequently mentioned species on the lists were also all very common North American species (led by the northern cardinal and the American crow), and all of the top ten most numerous birds in the count were also North American species that are found in large flocks (the 4,793, 261 snow geese topped this list!). There is, though, a growing international participation in the count with birders from 140 countries participating! Pennsylvania, by the way, was second only to California in total number of checklists submitted, and looking down the list of names of participants who filled out check lists from Pennsylvania counties, I found a number of regular readers of this blog! Let’s try to get even more of us out there this year!

Photo by E. Denes, Wikipedia Commons

Some observations from the 2017 GBBC include the continuing southerly drift of a number arctic and northern forest dwelling bird species. The pink-footed goose, for example, a Greenland species that a few decades ago was almost never seen in North America now is regularly observed by GBBC participants in Nova Scotia, Connecticut, New York and New Jersey! The great grey owl, a species of the northern, boreal forest of Canada and Alaska (and the northern mountains of U.S. Rockies and Cascades) was observed in northern Minnesota and New York. The great grey owl is the largest North American owl and has a voracious need for food in the winter (each owl must

Photo by A. List, Wikimedia Commons

eat seven, vole-sized mammals each day to sustain themselves). Limited food supply in their Canadian ranges is thought to be the ecological force pushing them southward into the Lower Forty-eight Sates.

Also, the Bohemian waxwing, a slightly larger version of the relatively common cedar waxwing, is like the grey owl a bird of the northern boreal forest and muskeg. Like the cedar waxwing, the Bohemian waxwing forms large, foraging and migrating flocks that may wander over vast areas that includes parts of the western Lower Forty-eight States. In 2017, though, GBBC observers reported 200 Bohemian waxwings in New Hampshire, including a flock of 40 feasting on crabapples!

The relatively mild winter weather last year had two interesting impacts: 1. It may have been responsible for the reduction in overall numbers of birds reported from bird feeder stations across the country (it is hypothesized that many birds in the warmer than average conditions relied more on natural foods rather than human-provided seeds and suet), and 2. A number of migrating species arrived in their spring and summer ranges many weeks before historical averages. These included common grackles and red-winged blackbirds in the Eastern United States and Canada (they were widely spread in both areas in late February), killdeer and American woodcock in New England and around the Great Lakes (they also arrived there in mid to late February), and tree swallows setting historically early spring arrivals in Illinois, Quebec and Massachusetts.

Photo by D. Wicks

Greater sandhill cranes ( a species I have discussed in posts from New Mexico and from Wyoming) are also found here in the Eastern United States. Most of these eastern sandhill cranes migrate to Florida in the winter and to areas around the Great Lakes (especially Wisconsin and Michigan) in the summer (although there is a small sub-population of Florida cranes that stay in Florida year round and do not migrate). To the left is a picture of a yard-full of sandhill cranes in Florida that a friend (Don Wicks) just sent me (probably to taunt me with their “cold” 63 degree weather!). Observations by GBBC participants on these cranes indicate that some of them are overwintering further north than ever before (in Alabama’s Wheeler National Wildlife Refuge, for example) and are migrating north and especially to the northeast earlier and in greater numbers than ever before and breeding in places where they have not bred before. Breeding pairs of sandhill cranes, in fact, have been reported in Pennsylvania, New York and throughout New England!

The species that I counted for my all of my Great Backyard Bird Count lists were as common as could be. All of my birds were in the top ten of the “most frequently listed” species. My birding experiences don’t range into wild, exotic discoveries. My birds were cardinals, juncos, blue jays, titmice, chickadees, and crows, and I was very pleased to see them!

Some years ago I was giving a talk at a conference about Deborah’s and my Virtual Nature Trail and the actual, physical nature trail on our campus that was the inspiration for it. At the end of my presentation I was asked a question, “what was special, or unique about this nature trail?” I sensed an undertone to the question of “why would anyone want to go see this trail?” Usually you come up with answers to questions like this much later, but somehow I found the answer right away: There is nothing particularly unique or “special” about this trail, and this is what makes it so important. It is the beauty in the ordinary, as Bill Bryson once put it “the low level ecstasy” of the common species and common terrain that make this site so wonderful. Sitting back and seeing what is around you in nature always elevates and inspires you!

And, to me, this is what makes the Great Backyard Bird Count and the sight of all of those ordinary birds that every day gobble down my sunflower seeds, corn, peanuts and thistle, so amazing. They are common but each individual is a work of wonder and beauty!

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