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All posts for the month March, 2014

By Jim White, Associate Director, Land and Biodiversity and Amy White, Teacher Naturalist

So you think you can dance? Well maybe you can, but I bet you can’t rival the 300-foot high, spiraling dance performed each Spring by the “mud bat”, or more properly the American Woodcock. Nor could you match the bird’s beautiful warbling song as it plummets back to the earth to strut around the ground, showing off for any potential mate.  In his landmark book, A Sand County Almanac, noted conservationist Aldo Leopold penned the term “Sky Dance” for this bird’s remarkable mating ritual.

An American Woodcock hides in the leaf litter of the forest floor, and is very difficult to see until they move.  Photo by Jim White.

An American Woodcock hides in the leaf litter of the forest floor, and is very difficult to see until they move. Photo by Jim White.

The Sky Dance is performed only by males and only in the right habitat: on and above open sandy, gravely, or short grassy areas adjacent to shrubby old fields and very young woodlands.  The dance begins in the twilight glow just before sunrise or after sunset.   It starts when the male flies to his chosen “singing ground” from the nearby vegetation and begin to call, emitting a loud nasally, buzzy sound or “peent” every three seconds or so.  While peenting, this chubby little shorebird wattles around the small area in comical fashion. Suddenly the peenting stops and the bird takes flight, rising in ever tightening circles high into the air.  With each wing beat a twittering sound is produced as air rushes through the first three primary wing feathers.  When reaching the desired altitude (as much as 300 feet) he stops climbing and plummets down to earth: as Leopold describes, “he tumbles like a crippled plane”. On the way down the woodcock emits a beautiful, soft, liquid warbling sound. Just before crashing, he levels off and lands, usually near where he took off, and begins to peent: starting the dance over again.  The entire dance, like so many types of dancing, is designed to impress the opposite sex – in this case, the female woodcock.  Sounds of the American Woodcock can be found here.

Some may describe the American Woodcock as an odd little bird and indeed it is unusual in several ways. Taxonomically, it is classified as a shorebird and yet it rarely visits the shore.  It is globular in shape, with large eyes comically positioned high up on the side of its oversized head.  And it has a very long bill (compared to its body size), which it uses to probe the soil for worms and other invertebrates. The tip of the bill is flexible, an adaptation that enables the woodcock to capture worms while thebill is still well below the ground surface.

The American Woodcock ranges over much of the eastern half of the US and southern Canada.  It appears that in recent years, woodcock populations are declining due to loss of the early successional habitats that they require.

Usually, you only see American Woodcocks in flight right around first light or last light.  Otherwise, one occasionally kicks them up in woods and thickets by surprise during the day.  Photo by Derek Stoner.

Usually, you only see American Woodcocks in flight right around first light or last light. Otherwise, one occasionally kicks them up in woods and thickets by surprise during the day. Photo by Derek Stoner.

This year appears to be a particularly good year to observe the Sky Dance, and we have been fortunate enough to witness several such dances in locations scattered throughout our area this Spring.  The best way to see the Sky Dance is to find a relatively flat, open area with low grass or bare substrate that is near young woodlands. If possible, position yourself so that you are facing towards the sunset, so that you can see the birds as they fly against the brighter western sky.  Get to your viewing spot at sunset and wait quietly until it starts to get dark.  If the woodcock are going to perform they will begin 20 to 30 minutes after sunset.  If you like to get up early you can also see the birds in the morning, about 45 to 60 minutes before sunrise. Either way, the best viewing conditions are with clear skies and little to no wind. 

The Sky Dance is one of the many natural phenomena that anyone interested in nature should try to experience at least once (if not every year, as we try to do).  It’s a great way to celebrate the end of Winter and to welcome the arrival of Spring!

By Joe Sebastiani, Seasonal Program Team Leader

On Thursday, March 27, 9am to 3pm, I will be conducting a citizen science field trip to seek Rusty Blackbirds in New Castle County, participating in an effort called the Rusty Blackbird Blitz.  This field trip is free for members of the Delaware Nature Society, and $15 for non-members.  Rusty Blackbird (Euphagus carolinus) is a scarce, declining, and poorly known blackbird species that prefers to live and feed in swamps, bogs, beaver ponds, and other wooded wetlands.  Unfortunately, over the last 40 years, this species is thought to have declined 85-95% across its range probably due to wetland habitat loss and disturbance.  However, the causes of this steep decline are largely unknown, and the International Rusty Blackbird Working Group is leading the effort to learn more.  Delaware Nature Society, with the help of University of Delaware PhD student Desiree Narango, is coordinating the Rusty Blackbird Blitz effort locally.  Our field trip is part of this project to identify spring migration stopover sites that might be important to their survival.

Female Rusty Blackbirds are fairly distinctive, with a broad eyestripe, pale eye, and rusty feather edges.

Female Rusty Blackbirds are fairly distinctive, with a broad eyestripe, pale eye, and rusty feather edges.

Why go out and look for Rusty Blackbirds now?  In Delaware, Rusty Blackbirds are migrating through the state from their wintering grounds further south.  Rusty Blackbirds are on their way to the wild boreal forests of Canada and Alaska to nest in boggy wetland areas.  The migration period in Delaware is roughly early March through mid-April.  Rusty Blackbirds stop and feed along their migration route and can be found in wooded wetlands flipping over wet leaves, and poking along water edges for food.  On our field trip, we will visit a variety of such wetlands looking for these birds, which travel in small groups of less than 100.  We will also be listening for their spring song, which sounds like a creaky, rusty door hinge.

Here, a male Rusty Blackbird forages along a wet woodland, their favorite habitat on their wintering and breeding grounds.

Here, a male Rusty Blackbird forages along a wet woodland, their favorite habitat on their wintering and breeding grounds.

Since March 1, Delaware birders have been looking for Rusty Blackbirds, and contributing their sightings to the Blitz project by entering them into eBird.  Anyone can participate, and all you need is a free eBird account.  When entering your sightings, choose Rusty Blackbird Blitz when indicating the type of birding you were doing.  Thirty reports of Rusty Blackbirds have been entered into the system through today, and the biggest flock reported so far was 70 at Bombay Hook National Wildlife Refuge on March 22.  70 is a large number to see these days.  In the past, their migratory flocks were referred to as “spectacular, noisy, and ubiquitous”*.  This is certainly not the case today.

By the time breeding season rolls around for Rusty Blackbirds, they lose the rusty edges to their feathers and appear black with a pale eye.  Rusty Blackbirds are very easily confused with the much more common Red-winged Blackbird, Common Grackle, and Brown-headed Cowbird.

By the time breeding season rolls around for Rusty Blackbirds, they lose the rusty edges to their feathers and appear black with a pale eye. Rusty Blackbirds are very easily confused with the much more common Red-winged Blackbird, Common Grackle, and Brown-headed Cowbird.

Large-scale, international citizen science data collection projects like the Rusty Blackbird Blitz are helping scientists collect the data they need to learn more about declining species.  The Delaware Nature Society is proud be a part of such an effort which could lead to more effective conservation of this species and the habitats it requires.  What will we learn about their spring migration stopover sites in Delaware?  Join our field trip on Thursday to help find out, and if you would like a chance to see Rusty Blackbirds.  Register by visiting www.delawarenaturesociety.org or by calling (302) 239-2334.  If you can’t g0 on the trip, keep you eyes out for these interesting blackbirds, and listen for their creaky, rusty-door-hinge sound.  If you find some, get photos and note your location and the date.  If you do not use eBird, but find these birds, you can report them to me by emailing joe AT delawarenaturesociety.org.

*(Avery, Michael L. 2013. Rusty Blackbird (Euphagus carolinus), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu.)

Photos courtesy of the International Rusty Blackbird Working Group.

By Mary Ann Levan, Teacher Naturalist

The next time the polar vortex dips down our way, here’s a way to take some pleasure from it…call to mind the forgotten joy of a “Snow Day!” announcement and head outside to look for signs of animals!  A cold winter morning can surprise you with a breathtaking pastel sunrise.

Cold, pastel sunrise.  Mary Ann Levan.

Cold, pastel sunrise. Mary Ann Levan.

Speaking of breathtaking, some folks even have a tradition of getting out on the very coldest day of the year.   This intrepid group hiked the trails of Ashland Nature Center at the beginning of the “Season of the Vortex”, fully equipped with face masks and multiple hand warmers stuffed into our mittens.

Prepared for yet another Polar Vortex!

Prepared for yet another Polar Vortex!

This snapshot of the thermometer confirms that it was at least one of the coldest days of this very cold winter.

This snapshot of the thermometer confirms that it was at least one of the coldest days of this very cold winter.

On this very cold and snowy exploration of the Ashland fields and forests, we were delighted to find a dazzling array of tracks left behind by animals also exploring the grounds in search of food and water.  After this first taste of “animals in winter”, the hunt was on!  As the snows continued to fall and the wonderful packed base developed, I made trips into open fields, past streams and woody field edges in search of signs of animals.  Amy White joined me to go out on foot, skis, and snowshoes for what has been a once in a lifetime experience of polar life at the low latitudes!  Following is a composite of some of the tracks we found on these winter explores. 

This winter has had multiple deep snowfalls, severe cold, and persistent snow cover, making it more difficult for animals to excavate to plants they rely on for food. Starting in open terrain, we find a common track of an animal that often crosses open fields but browses for food along field edges and in woods as well.  In severe winters with heavy snow cover, we find these animals in our yards as well, nibbling on ornamental plantings for survival.

Deer tough it out in the winter, and this year must have been rather stressful on them.  Photo by Mary Ann Levan.

Deer tough it out in the winter, and this year must have been rather stressful on them.

Deer are ungulates, or mammals with hooves.  Deer tracks are recognizable because they are often large (1.25 – 3.5 inches) and heart-shaped.  But the foot also has a pair of small digits called dewclaws that only leave an imprint in soft ground or snow.  These tracks were made in a thin layer of fluffy, new snow over a deep base of hardened snow below.  They show the dewclaws especially well.

Although these were the tracks of a single animal, White-tailed Deer often travel in groups, leaving a trail of many tracks where several animals have passed together.   Photo by Mary Ann Levan.

Although these were the tracks of a single animal, White-tailed Deer often travel in groups, leaving a trail of many tracks where several animals have passed together.

A real treat in these cold, open areas were these bird tracks that appeared suddenly, strolled about in leisurely patterns and then disappeared.  These were made by a large bird that was walking in the field alone, stopping at exposed grassy spots to probe the open ground.  The tracks called to mind an American Crow, which move in small groups, but are often seen alone in open fields walking and wandering, appearing to be attending both to the ground and the sky as they move about.

Bird tracks in the snow.  Photo by Mary Ann Levan.

Bird tracks in the snow.

Fields and meadows are home to many types of rodent such as mice and voles.  When there is no snow cover, you can search meadow grasses for trails or “runways”, which are usually bare-ground, slightly dug routes shown by vague impressions of passage through the grass. These trails are also built under the snow; the snow provides cover from predators as the rodents seek out tender bark for winter calories.  These trails were found on the Red Clay Creek floodplain.  They were probably made by the meadow vole, and were uncovered during a period of snow melt that exposed the animals’ hidden activities!

Crazy mouse or vole trails.  Photo by Mary Ann Levan.

Crazy mouse or vole trails.

These tracks presented the unlikely scenario of a lone, intrepid tiny mammal, again probably a vole, crossing a vast open field in full view of aerial predators.  These prints cover about 100 feet of open ground before disappearing into a hole beneath a tree.

A brave small rodent crossed over the snow, in full view of predators that could have been watching.  Photo by Mary Ann Levan.

A brave small rodent crossed over the snow, in full view of predators that could have been watching.

Canada Geese are another common visitor to the Red Clay Creek floodplain and adjacent marshlands.  The webbed feet are evident in these tracks made by quite a crowd of geese in the Ashland marsh.

Goose tracks.  Photo by Mary Ann Levan.

Goose tracks.

Another track common in marshes and stream corridors was that of the raccoon, which finds much of its food in “aquatic prospecting”.  Despite the cold and snowy conditions, raccoons seemed to be quite active this winter; their tracks were frequently seen.  Raccoons make tracks in pairs, a front foot together with the opposite hind foot.  The hind foot (about 3.5 inches) is markedly bigger than the front (2.25 inches), the hind looking like a foot and the front more like a hand.  Each foot leaves imprints of 5 digits, often with prints of claws, as well.

Front and rear raccoon tracks.  Photo by Mary Ann Levan.

Front and rear raccoon tracks.

If you have a backyard bird feeding station, you might be battling very determined and clever raccoon efforts to extract the feed intended for birds.  This design seems to be working well at defeating a very determined nocturnal visitor!

Raccoon scratch marks on my bird feeder!  Photo by Mary Ann Levan.

Raccoon scratch marks on my bird feeder!

Along the hedgerows of brush, vines and young trees that divide the open fields, there are many signs of Gray Squirrel activity.  Though these squirrels do build nests of twigs and leaves for warmth and protection and also make food caches of nuts and seeds, they are quite active on many winter days.  Squirrel tracks are in rows of pairs,  the distance between the track groupings depends on how fast the animal was bounding as it jumped across the ground.  The hind tracks lead the front foot tracks, showing how the back feet fall in front as the animal moves.  If the animal is moving quickly and nervously, you might not see heel marks in the track since the animal is running too fast.  Squirrels have long, curved toenails that act as hooks for tree climbing, and often leave imprints in front of the toes.

Here are tracks of both a squirrel and a fox, which seem to have passed at different times.  The squirrel tracks do not look especially hurried and the fox tracks do not look especially  interested or rushed!  Photo by Mary Ann Levan.

Here are tracks of both a squirrel and a fox, which seem to have passed at different times. The squirrel tracks do not look especially hurried and the fox tracks do not look especially interested or rushed!

Rarely, we came across the trail of an Eastern cottontail rabbit.  Their tracks are large (> 1 inch), with the back foot much bigger than the front and the hind foot falling in the front in the track pattern.  The feet are furry, making the toes hard to count.  In the winter when grass is covered or less available, rabbits feed on twigs, buds and bark, and stay close to their food source and protective cover.

Eastern Cottontail tracks.

Eastern Cottontail tracks.

This enchanted winter is gradually giving way to springtime, if not in warm temperatures, at least in longer hours of daylight and sunshine.  Is there more time to get in more snowfalls this season?  If so, perhaps we can capture the tracks of the springtime animals like the groundhog and the skunk in the glorious cold fluff of winter rather than in the oozy brown muck of springtime! 

Especial thanks to Amy White for her companionship, interest, patience and smart phone on many of these winter adventures.

Amy White, a Delaware Nature Society Teacher Naturalist, enjoys a recent snowfall.

Amy White, a Delaware Nature Society Teacher Naturalist, enjoys a recent snowfall.

 

By Lori Athey: Backyard Habitat Coordinator

The Delaware Nature Society Native Plant Sale (May 1- 4) theme this year is “Inspired Plant Combinations: Create Your Garden Masterpiece”.  Got a spot in your garden that needs some POW?  We can help!

When considering buying new plants, first note the light and soil moisture conditions where you want to plant.  Second, consider how much space (height and width) you want the new plant to fill. Our plant sale catalog gives you all the information you need to make the right plant selections. If you are starting from scratch with a new bed, you will want a combination of plants…maybe a small tree, a few shrubs and some groundcovers.  If you are adding plants to an existing bed think about what is already there, what type of garden interest are you trying to achieve, and how will your new plant fill that role?

A female Ruby-throated Hummingbird visits Monarda in a backyard garden.  Photo by Hank Davis.

A female Ruby-throated Hummingbird visits Monarda in a backyard garden. Photo by Hank Davis.

Back to that POW!  One of the most exciting wildlife experiences in the garden is when you have a visiting Ruby-throated Hummingbird.  Below is a list of my favorite plants to attract the Hummingbirds.  They all flower in shades of red, orange & deep coral pink.  How is that for POW? 

*Wild Columbine/Aqualegia canadensis blooms April-May, perennial

Wild Columbine is another hummingbird favorite where you can see them feed from underneath the flower.  Photo by Joe Sebastiani

Wild Columbine is another hummingbird favorite where you can see them feed from underneath the flower. Photo by Joe Sebastiani

*Fire Pink/Silene virginica blooms April-May, perennial

Fire Pink POW!  Photo by Joe Sebastiani

Fire Pink POW! Photo by Joe Sebastiani

*Red Buckeye/Aesculus pavia blooms in May, small tree or large shrub

*Trumpet Honeysuckle/Lonicera sempervirens blooms May to frost, woody vine, hummers prefer the red and coral selections

*Indian Pink/Spigelia marlandica blooms June-August and sporadically to frost, perennial

*Beebalm/Monarda red selections bloom June-July, perennial

*Turk’s Cap Lily/Lilium superbum blooms in July, perennial bulb

The tall Turk's Cap Lily will add a big color splash with a gorgeous structure, and in addition to hummingbirds, you will see butterflies nectaring on it.  Photo by Joe Sebastiani

The tall Turk’s Cap Lily will add a big color splash with a gorgeous structure, and in addition to hummingbirds, you will see butterflies nectaring on it. Photo by Joe Sebastiani

*Plumleaf Azalea/Rhododendron prunifolium blooms July-August, large shrub

*Cardinal Flower/Lobelia cardinalis blooms July-September, perennial

*Trumpet Vine/Campsis radicans orange selections bloom July-September, woody vine

Trumpet Vine, Campsis radicans, really swallows up a feeding hummingbird.  Photo by Hank Davis.

Trumpet Vine, Campsis radicans, really swallows up a feeding hummingbird. Photo by Hank Davis.

Ruby-throated Hummingbirds arrive in Delaware in mid-April and are residents through the summer.  In the fall, you will see an increase in their numbers since young birds are around and fall migrants are visiting our area.  By October, they are virtually all gone with the exception of a straggler or two.  Knowing this, you can plan to have a succession of blooms for them.  Add a sugar-water feeder to your garden for supplemental food, and be sure to clean the feeder regularly so that the water doesn’t spoil and make them sick.  Boil a solution of 4 parts water and 1 part sugar so that it keeps in the fridge longer.  Replace the solution at least once per week, and at the same time, clean the feeder with a 10% bleach/water solution.  This way, your garden hummingbirds will be happy and healthy.  Additionally, if you really want to spoil them, you can provide a “mister” that creates a fine mist of water that hummingbirds love to bathe in.   

Of course, Cardinal Flower, Lobelia cardinalis, is a well known and popular hummingbird attracting plant.  The reason?  It works!  Photo by Hank Davis.

Of course, Cardinal Flower, Lobelia cardinalis, is a well known and popular hummingbird attracting plant. The reason? It works! Photo by Hank Davis.

Plant enough of the perennials to create a good-sized patch, so you will get their attention.  Vines should be planted on a mature deciduous tree (like an old Wild Cherry) or a very sturdy structure.  For additional interest in the fall and winter, add a few Winterberry Hollies (Ilex verticillata both male and female) or Red Osier Dogwoods (Cornus serecia) and underneath it all, plant with Green-and-Gold (Chrysogonum virginianum).By adding a few of these native plants, your yard should be humming with activity all summer long.  Excited for spring yet!!!