Phenology Note: February 28, 2010 - Collembola

Although not considered species of special interest in the Eastern Pennsylvania Phenology Project, Collembola are a unique group of Arthropods that are a sign of warming temperatures signifying the coming of spring.  Collembola are generally 1-5 millimeters and most are very good jumpers.  For most of the winter, these insect-like hexapods live beneath the ground, in tree trunks, and under rocks.  During the summer, tend to live under leaf litter and just below the surface of the ground.  During the fall and winter, some Collembola move around (primarily by jumping) and can be incredibly numerous on the forest floor. 

One common Collembola that congregates like this are "snow fleas" which belong to the family Hypogastruridae.  Groups of hundreds often congregate on snow patches and puddles once the temperature is in the thirties.  The Hypogastruridae that often gather on top of the snow are like the ones pictured below.  Under magnification, they appear blueish with small hairs.  With the naked eye, these Collembola appear black or sometimes purple.  This particular group is easiest to find during late winter/early spring and late fall/early winter.  This time of year, the groups gather in sunny snow patches and puddles.

Hypogastrura sp. Snow Flea

Hypogastruta nivicola - Snow Flea

Although the Hypogastruridae are the most common Collembola this time of year, there are several other species present.  One interesting species is Hydroisotoma schaefferi.  This species was introduced from Europe and is now fairly common in puddles and springs from January to April.  These do not congregate like the previously mentioned species, they are often found in small groups in water.  This species often looks brownish-orange with a dark line down the back.

Hydroisotoma schaefferi - an introduced Collembola

A Collembola in the family Isotomidae surrounded by Hypogastrura.

There are many species of Collembola, many of which mark the arrival of spring by becoming more abundant and more evident.  When the ice starts melting and puddles begin forming, be sure to look for these extremely small creatures while exploring the woods.

Photos: Corey Husic

As February wanes - Part II

Milder temperatures and lots of rain.  It is starting to seem a bit more like spring.

Yesterday at Green Lane (Montgomery County), quite a few birders were gathered to see some unusual species (a Eurasian Widgeon and a Barnacle Goose).  A lot of snow geese were on the water and I happened to notice that the ice on the reservoir was clearing.

Snow geese are beginning to return north to their arctic breeding grounds.  You can see a map of their major migration routes at http://www.paulnoll.com/Oregon/Birds/migrate-Snow-Geese.html.  We are blessed in eastern Pennsylvania to see these beautiful birds this time of year in farm fields and in bodies of water.  One of the most spectacular places to see large congregations of these birds (along with Tundra Swans) is the Middle Creek Wildlife Management Area in Lebanon and Lancaster Counties.  There is some information about this species and Middle Creek at the PA Department of Environmental Protection site: http://www.portal.state.pa.us/portal/server.pt/community/middle_creek/13905

On March 5^th, Jacobsburg State Park (http://www.dcnr.state.pa.us/Calendar/view_event.asp?CalendarID=17645&Location=List), the Lehigh Gap Nature Center (www.lgnc.org), and the Lehigh Valley Audubon Society (http://www.lehigh.edu/~bcm0/lvas/index.html) are all leading trips to Middle Creek.

As my son and I returned to Kunkletown after our excursion to Green Lane yesterday, we saw the first blooms of Coltsfoot (Tussilago farfara) on the south side of the Kittatinny Ridge.  Alas, the first leaves of the invasive species Garlic Mustard (Alliaria petiolata) were also apparent. This plant is on the “Least Wanted” list of the Plant Conservation Alliance’s Alien Plant Working Group; you can find out more at http://www.nps.gov/plants/alien/fact/alpe1.htm.  A typical feature of invasive plants is their ability to get a jump start on the growing season – being one of the earliest to emerge from the ground.  In the case of invasive shrubs, they will be among the first to leaf out.  Invasive species have many other competitive advantages that will likely be discussed in future posts.  Coltsfoot is a plant that readily shows up in disturbed places, is a very early plant to sprout as winter gives way to spring, and is considered by many to be another invasive species (see http://www.invasive.org/browse/subinfo.cfm?sub=6564 ).

My husband and I returned to the spot later in the afternoon.  Below are some pictures taken yesterday of Coltsfoot and Garlic Mustard leaves that had recently emerged. 

Coltsfoot flowers emerging from the leaf litter (Photo by H. David Husic)

A flower and buds of Coltsfoot (Photo credit: H. David Husic)

The sunny bright flowers of Coltsfoot close-up (Photo by H. David Husic)

Garlic Mustard leaves - the first of the season
(Photo by H. David Husic)

If you have creeping Sedum spurium plants in your garden you may also see that reddish leaves of this succulent have also begun to bud out (at least in Kunkletown).

On spring peepers

With the warming temperatures and the rain, it is possible that we could start hearing spring peepers.  You can read a description of these and hear the sound of their singing at: http://lgnc.org/resources/soundguide/peeper_spring.

Singing Spring Peeper (Photo by Corey Husic)

As February wanes

For some reason, I awoke very early this morning so figured I would get up and be productive.  The past week was incredibly hectic so I have a lot to catch up on.

At 6:15 a.m., I was treated to a cardinal song.  This was the first time this year that I heard one of the elements of the “Dawn Chorus” that will become much more prominent as we head into spring.  Both male and female cardinals sing, so because it was still dark, I cannot tell you which gender I heard.  But if you are not familiar with the sounds that cardinals make, you can listen to some at the Cornell Lab of Ornithology site:  http://www.allaboutbirds.org/guide/Northern_Cardinal/sounds.  Under “songs”, the second recording is what I heard this morning.

A few minutes later, the crows started squawking.  From a phenology point of view (and aesthetically), this was much less interesting.  Crows are here in Kunkletown all year round and they are routinely noisy.

Starting with fresh snow Sunday night into Monday this past week, the cold returned and I didn’t hear or see very many new signs of spring.  Several people reported that they were seeing chipmunk and skunk activity.  I saw another live skunk last night south of the Kittatinny Ridge.  We have seen raccoons roaming about and their tracks in the remnants of snow in our woods.  And I don’t know about you, but I have seen a lot more deer grazing in fields and along roadside edges lately now that much of the snow has melted.

On the rare occasion that the sun came out recently, I would hear the “Peter, Peter” song of the Tufted titmouse (http://www.allaboutbirds.org/guide/Tufted_Titmouse/sounds; recording number 2).  Throughout the winter you can hear their calls (also found at the above link), but as the sun rises higher in the February sky, you will hear these birds begin to sing more frequently.  I am not sure whether they are marking territory, calling for a mate, or just simply celebrating the appearance of the sun!  No matter.  They are fun to listen to.

We are still seeing juncos at our feeders north of the Kittatinny Ridge, but we didn't see any last week in Bethlehem at the Housenick-Johnston Estate when we did a survey for the Great Backyard Bird Count.  Others from the Lehigh Valley reported that they are not seeing them any more either.

We are fortunate to have several resident Pileated Woodpeckers at our farm.  Yesterday was the first time this year that I saw a pair hanging out together.

Near the Bethlehem library, there are several spring flowering cherries and magnolias in the Japanese garden and between the backside of the building and the Monocacy Creek/Fahy Memorial Bridge.  I noticed on Friday that the buds have become more prominent and there is more color in the twigs.  The annual explosion of blossoms is really a lovely sight and maybe it isn’t so far off!

Some people are beginning to send me wonderful messages for this project.  I have included two excerpts:

First, from a new member of the Lehigh Valley Audubon Society (LB):

“I'm not much of a blogger (totally new to me!), but I can report that when we had those near-record temps a few days ago, I cleaned out & filled the birdbath and had the delight of seeing a tufted titmouse take the bath of his life! A robin waited in line...I'm always concerned about the wild birds having water...esp. in the winter & for the water-loving robins!  We also winter fed all kinds of birds...juncos, black-capped chickadees, white-throated sparrows, cardinals...the juncos are not appearing in small flocks anymore...are they off to Canada?  I used a feeder this very harsh winter; but otherwise, I'm not a big fan of feeders--they seem unnatural to me in fair weather...but I can see the opposite argument...I DO leave a small pile of peanuts each am on a cafe table (they go neatly & fast) for our wild 'pet' squirrel, who competes with the cardinals and chickadees for them...the squirrel seems to favor one of his front legs (overall he gets around)....Either that or he's Working It! to keep raking in the peanuts!”

The second report comes from a naturalist who lives north of the Lehigh Valley (PK):

“I'm always looking for the signs of spring and beyond. In fact I used to record in a note book the dates of when things started to grow, bloom and go to seed. [DH:  This is exactly the type of data we would love to know about.  Past records are so very important!] I always look for the swelling of maple buds as the beginning of the growing year. I've been noticing that already in the Lehigh Valley. On Friday I heard my first Song Sparrow of the year here in Lansford. Also heard the first Killdeer. One of my favorite things is to lift out the leaf litter to see what’s emerging underneath it. ….In about two weeks the suckers in Tuscarora Lake will start migrating upstream to spawn. It's like seeing Salmon in a way. They actually show breeding colors at this time of the year. Then there's that first warm day when the Wood Frogs start to "quack". I'm looking forward to recording and sharing this data.”

This past Thursday into Friday, we had a lot of rain (over an inch) which has softened up the ground.  Yippee!  It is the start of the “mud season”.  Today, the Lehigh Valley is supposed to have temperatures in the 50’s and on Monday, the forecast is for even warmer temperatures (in the 60’s) and another heavy bout of rain.  Will this be enough to get the salamanders moving?  Stay tuned.  It is likely to be a week of changes so let me know what you are observing.

Phenology Note: February 20, 2011

The first "species of special interest" of the year are beginning to become active.  The first is Skunk Cabbage.  The unique flowers are beginning to emerge in wet, wooded areas.

Although not yet blooming like the Skunk Cabbage, the buds of Red Maple trees are beginning to grow.  Be on the look-out for both of these early-blooming species.

What To Look For: late winter/early spring

Here are some species to look for while outdoors in February through March. The species listed below are a few of the "species of special interest" to the Eastern Pennsylvania Phenology Project.

One of the most common tree species in eastern Pennsylvania is the Red Maple (Acer rubrum).  These common trees of forests, parks, and roadsides begin blooming around the end of March (one of the first trees to flower) and are a sure sign of the start of warmer weather and lengthening days.  The flowers range from light orange to dark red.

Skunk Cabbage (Symplocarpus foetidus) is a common plant of wet, swampy areas. During the summer, the large, lettuce-like leaves are easy to spot. However, before the leaves emerge, Skunk Cabbage flowers poke through the leaf litter--representing one of the earliest native spring flowers in this region. These unusual flowers do not even look like what most people would consider a "flower".  Keep an eye out for these flowers when visiting a wooded wetland or other area that is permanently wet.  The plant displays interesting biochemistry in order to produce heat that not only can melt snow around the plant but serves to volatilize chemicals that give the plant its characteristic (bad) smell.  However insects such as flies are apparently attracted to this smell and serve as pollinators for this plant.

Another early spring bloomer is Coltsfoot (Tussilago farfara) a member of the Asteraceae family. This plant is native to Europe and Asia; it was likely brought to this country for medicinal purposes.  Despite its use as a cough suppressant and for treatment of asthma, the plant does produce toxic alkaloids.  Many people consider this a nuisance (or noxious) weed, but on the slopes of the Kittatinny Ridge, the bright yellow flowers which emerge before the leaves, are a sure sign of spring.

Although butterflies are usually associated with summer, there are a few species that can emerge as early as late March.  The first of these is the Mourning Cloak.  Unlike many species which overwinter as a caterpillar or migrate, the Mourning Cloak overwinters as an adult butterfly, allowing it to fly around given a stretch of warm weather.  This species prefers wooded areas and is often easy to spot.  One was already spotted on Friday, February 18th in Cape May, NJ!



Spring Azure on its host plant lowbush blueberry (Vaccinium pallidum)

Another butterfly of early spring is the Spring Azure.  These small, gray and blue butterflies are common in wooded areas.  There are two types of Spring Azure: one that shows up around the end of March and stays for much of April and one that emerges around the end of April and is common in May. 


If you see any of the flowers or butterflies mentioned above, leave a comment on this blog post or email phenology@lgnc.org with the sighting information including the species, date, location, weather conditions, your name, contact information, and any other observations or notes that you have.

Big changes in the weather

After enjoying a reprieve from winter for two days, the weekend temperatures will only be in the 40’s and we have had 30 to 60 mph winds from the northwest today. Wow!  We all new it was too good to be true.  It is way too early for spring despite what the groundhog may have said.

My son Corey and I did a bird walk and count at the Housenick-Johnston Estate property in Bethlehem this morning for the Great Backyard Bird Count.  We saw 26 species.  Of particular interest was seeing the Red-bellied woodpeckers and Great blue herons paired up.  We saw almost 400 snow geese returning to the area before they head even further north. 

On the way down to the estate just over the Kittatinny Ridge near Point Phillip, we saw a skunk wandering around.  This is the first sighting of season although I smelled them on Muhlenberg’s campus last Tuesday (Feb. 15th) and further down the road we saw one that was road kill.  Skunks do not hibernate but do spend a lot of time during the cold months hunkered down in their dens – typically with one male and several females.  They can enter a state of torpor living off the fat that they stored in their bodies. When temperatures rise as they did this week, they will come out and search for some food.  They are omnivores.  Since there aren’t a lot of insects or worms around right now, they might look for small vertebrates, seeds, or human garbage.

After our blustery bird survey, we headed home and were treated to seeing several blue birds flitting around front yards and an adult bald eagle soaring over a corn field near Klecknersville.

At home I noticed that the daffodils by the barn had emerged 1 to 2 inches.  The sun reflecting off the white siding always warms that flower bed.  This is problematic since the daffodils and crocuses tend to emerge very early, often to have their attempts to grow thwarted by the return of cold and snow!  I didn’t see any aconite flowers open yet and, here in Kunkletown, the snowdrops haven’t emerged yet.  The snow is melting enough so that I can see the green leaves of my hellebores.  These will be early bloomers as well, but not yet.

Snow geese in the Martins Creek/Forks Township area on Feb. 18th (photo by David Husic)

It can't be spring already can it?

As part of my Audubon TogetherGreen Fellowship project (http://togethergreen.org/People/FellowDetails.aspx?fellowID=132), I am getting ready to launch a new initiative to collect phenology data from eastern Pennsylvania.  There are many periodic events in nature: the budding of leaves and flowers in spring, the changing color of leaves in the fall, migrations, insects hatching, etc.  There are physical changes as well such as the melting of ice on lakes and ponds and the first and last frosts.  Many of us take notice of these seasonal signs without realizing the important stories that these events are telling us.  The timing of these changes in nature is influenced by a number of environmental conditions and the events are extremely sensitive to changes in the environment.  As such, collecting data on the timing of these events over time can give us important clues as to what is happening in our world.  The data collection can be done locally (your backyard), regionally (as this project will be), or nationally (as is being done by the National Phenology Network – see http://www.usanpn.org/ ).  The eBird project through the Cornell Laboratory of Ornithology is gathering international data that can be mined for phenology information (see http://ebird.org/content/ebird/).  Best of all, data can be collected by people of all ages.  A science background is not necessary, but a curiosity about the world around you is.

There will be a number of partners in this project including state parks, nature centers, college students, and schools.  Most importantly, we hope to involve individuals—members of the public—who can participate from their backyards or by participating in upcoming events at the parks and nature centers.  More details to follow in upcoming posts.

We were planning on rolling this project out in March, but nature has a way of surprising us.  After two unseasonably warm days in the region, some signs of spring have unexpectedly caught us off guard, so I realized that I had better get things rolling!

Several people have already been hearing the territorial songs of the Tufted titmouse.  I heard my first on February 1^st this year in Bethlehem.  On February 6^th, I heard the first cardinal singing in Kunkletown.  And friends in Bethlehem reported snow drops (Galanthus) blooming last week (as soon as the snow melted enough to uncover the plants).  These tiny bulbous plants are in the Amaryllis family and are often are among the earliest signs of spring in this area.  Until today, mine were covered by snow and ice, but should emerge soon.  Jacobsburg State Park employees noted that the Northern spicebush Lindera benzoin was already showing buds.

Snow drops (photo credit: Dave Husic)



Spicebush flowers (Photo credit: Corey Husic)


After an unusually cold winter, the last two days the temperature soared into the 60’s and rapidly melted the snow.  The ice began to retreat on our pond.  Today, we saw the first turkey vultures venture over the Kittatinny Ridge (Blue Mountain).  Some saw them yesterday.   Just south of the ridge, it is not unusual to see the vultures throughout the winter, especially just south of the Lehigh Valley.  My Winter aconite (Eranthis) started to bloom today.  This small low growing plant has rather large yellow flowers (relative to the plant size) and is a member of the Buttercup (Ranunculaceae).  Although both the snowdrops and aconite are commonly seen in this area, neither is native to Pennsylvania.

Perhaps the biggest surprise occurred at dusk – the first woodcocks were calling ("peent").  Although it was too dark to see the birds, you could hear the timberdoodle sound of their wings as they flew around our field.  They were in the exact location where my son just an hour earlier had said they may show up—soggy areas of our field where worms may emerge.  I had a report that a woodcock was heard in Lehighton yesterday as well.  According to the Birds of the Lehigh Valley, a publication of the Lehigh Valley Audubon Society, the earliest date for these was February 11^th (in 1998) in Revere – a small town south of Easton along the Delaware River.

Dan Kunkle at the Lehigh Gap Nature Center said there were two adult bald eagles at the Refuge today!  He also saw bluebirds checking out the nest boxes.

Have you seen signs of spring yet?  The temperatures will drop again, so these may have been teasers, but important observations none-the-less.  And if anyone out there has pictures of these early species to share on this blog, let me know!