Autumn Leaf

autumn leaf, originally uploaded by donnallong.

The leaf is luminous. I like the sunlight highlighting the veins at the top of the leaf. I like the lack of perfection.

This leaf looks as it has had a life well lived. But, it's life is over now. Human life is the same way. If we don't live life like we mean it, then what is the point?

Bird Migration Routes - Do You Live Near One?

Flyways map courtesy Fish & Wildlife Service

Flyways are heavily traveled routes bird use during migration. During migration, birds tend to follow physical features such as coastlines, mountain ranges and river valleys.

In the 1930's investigators became impressed by what appeared to be four broad, heavily traveled "highways" in North America. This concept was based on several thousand records of migratory waterfowl.

The "highways" were only approximate and many birds migrate outside of them.

W.W. Cook identified seven generalized routes for birds leaving the United States on their way to various wintering grounds (see map above). The routes by which birds return northward in the spring are not as well known.

Look over the following list and the map above to see if you live on or near a migration route. 

Main Migration Routes in North America

Atlantic Oceanic Route (route 1) This route mostly travels across the Atlantic Ocean. It stretches from Labrador and Nova Scotia to the Lesser Antilles, then through a small group of islands to the mainland of South America. Since this route is almost entirely over water, the only way humans know about it, is through observations on islands like Bermuda and those islands along the way. Birds usually fly this route by both day and night.

Atlantic Coast Route and Tributaries (route 2) The Atlantic coastline is a regular route of travel. It has many famous birding hotspots for observing both land and water birds. About 50 different kinds of landbirds that breed in New England follow the coast southward to Florida and travel by island and mainland to South America. At no time are these air travelers out of sight of land. It is not however the favored migration highway. Only about 25 species of birds use this route to go to their winter homes beyond Cuba to Puerto Rico. This was known as the Atlantic Flyway. This is the route that covers the sky over Philadelphia, Delaware and the Jersey Shore.

Mackenzie Valley-Great Lakes- Mississippi Valley Routes and Tributaries (route 3) This migration route is the longest of any in the Western Hemisphere. It extends from the Mackenzie Valley past the Great Lakes and down to the Mississippi valley. Its northern end is on the arctic coast in the regions of Kotzebue Sound, Alaska and the mouth of the Mackenzie River. The southern end lies in Argentina.

For more than 3,000 miles, from the mouth of the Mackenzie to the Mississippi delta, this route is uninterrupted by mountains. Because it has plenty of trees and water, the area is a great place to view great numbers of migrating birds. During the height of migration, going to birding hotspots in the Mississippi Valley, allow birders to can see large numbers of many species. Swarms of birds are spotted on the islands off the coast of Louisiana. This was known as the old Mississippi Flyway. (route 4)

This route begins in the Mackenzie River delta in Alaska. Some places in this area, such as the National Bison range at Moise, Montana, have food in such abundance that birds stop here during migration to refuel. This was known as the old Central Flyway.

Pacific Coast Route (route 5) The Pacific Coast Route is not as long or heavily traveled as some of the others. Because of the nice living conditions, many species of birds breeding along the coast from the northwestern states up to southeastern Alaska either do not migrate or else make short journeys. This route has its origin chiefly in Western Alaska around the Yukon river delta. Large numbers of arctic-breeding shorebirds also use this route. This was known as the old Pacifc Flyway.

Pacific Oceanic Route (route 6) This route is mainly over water. It extends from the islands of the Bering Strait through the islands of the central Pacific and northward along the Asiatic Coast. Many seabirds that breed in the far northern coasts, southern coasts and islands migrate across the Pacific away from land and except when the breeding season approaches. Incredibly, birds navigate to tiny isolated islands in the middle of the vast Pacific Ocean.

Arctic routes (route 7) Some arctic nesting birds travel only a short distance south in winter. They fly mainly along the coast. The best defined arctic route in North America follows the coast of Alaska.

More Information:
Flyways.us
http://www.flyways.us/flyways/info

Information courtesy of: "Migration of Birds: Routes of Migration",http://www.npwrc.usgs.gov/resource/birds/migratio/routes.htm March 09, 2007. 

The Autumnal Equinox and Fall beigns

The autumnal equinox starts the fall season. It occurs on September 22 or 23 each year. The "fall" is my favorite time of the year. The crisp cool air and brilliant colors of the leaves urges me outside with camera in hand.

There are two equinoxes a year. One in spring and the other in autumn. The spring (or vernal) equinox happens on March 19, 20, or 21.

The seasons are reversed in the northern and southern hemispheres of the planet. When the northern hemisphere experiences autumn, the southern hemisphere is experiencing spring. 

On the equinoxes, the sun is directly above the Earth's equator. Day and night are of equal length all over the planet. The world receives twelve hours of daylight and twelve hours of darkness. The term equinox comes from the Latin and means "equal night".

The seasons signal that changes in length of daylight, temperature and weather are about to happen.

The seasons are caused by the changing position of the Earth in relation to the Sun. The Earth receives different amounts of sunlight during the year due to the tilt of the Earth. The Earth is like a spinning gyroscope and always points in the same general direction. The earth is tilted on a 23.5° degree angle and the sun shines on the planet  in a particular way. The north pole is generally tilted toward the north star and the south pole tilts toward the constellation of Octans.

Cold Days and Short Nights

The Autumnal Equinox begins the cold months. During the colder months, the North Pole is at it's greatest tilt away from the sun. The northern hemisphere then has colder temperatures, short days and long nights.

It takes a few weeks for the weather to change after the beginning of a new season. During autumn, there are alternating warm and cool days and cooler nights for several weeks.

On the day of the Autumnal Equinox, the Sun is positioned directly over the equator.  After this day, the northern hemisphere begins to tilts away from the sun. The weather becomes colder and the hours of daylight become shorter. This culminates in the shortest day and the longest night of the year, the Winter Solstice on December 22 or 23. Then the days grow longer until the Summer Solstice.

In 2010, the Autumn Equinox happens on September 22nd.

Birds of Prey Identification - best field guides

A Sharp-shinned Hawk hunting in my garden.

Identifying birds of prey can be a combination of how a bird looks and what it does.

How a bird looks focuses on color, plumage, marking and other easily seen details. This is called the 'field mark' approach. This works best when you have a clear and close look at an animal. But, if the birds is flying a mile overhead, then the field mark system doesn't work as well. This is where the behavioral approach comes in handy.Instead of looking for plumage details or eye color, more emphasis is placed on how a bird behaves. This behavior approach looks at a number of factors.

• how a bird appears to fly
• the rhythm of the flaps and glides while flying
• does it fly with soaring, rocking motions, long flights or short bursts
• the bird's overall shape, size and color and silhouette
• the bird's behavior
• any calls or sounds made

All of these behaviors and clues add up to a good identification. None of it focuses on what we can see up close.
Birds of prey species often have distinctive ways of flying and holding their wings. If you learn these profiles and behavior you'll will be able to identify raptors even when they are circling thousands of feet above you.I often see Red-tailed Hawks and Turkey Vultures flying overhead. When they are tiny specks in the sky is not easy to distinct between the two birds. I focused on identifying a Turkey Vulture. I figured if I could learn that one bird then I could judge the other birds of prey by it.

The Turkey Vulture is a dark underneath with a dark body, dark V-shape on the wings and translucent white "fingers" at the end of its wings. A soaring Turkey Vulture's silhouette takes on a more pronounced V-shaped than a Red-tailed Hawk. And a Turkey Vulture often looks huge, where a Red-tailed Hawk can look smaller.

I often check manner of flight, color pattern of feather and body and whether other birds are in the sky with it. I have gotten pretty good at telling a Turkey Vulture from any other bird. I think the behavioral approach used along with the field marks approach, helps to make a very knowledgeable birder. There is much to learn about identifying birds of prey. We can't cover it all here.


The best books I have found for identifying are ...

Hawks: All the day-flying birds of prey seen in North America (Peterson Flash Guides)
I like this laminated guide. It folds neatly to fit in a pocket.  This guide is perfect if you are a beginning birder. The guide covers the most common day-flying species in North America. It is not overwhelming with too many species, plumages, ages, etc.
As the years have gone by, I like the simplest equipment possible. This folding laminated guide is my first choice to carry.
















Field Guide to Hawks of North America
This a classic Peterson field guide teaching the field mark method of identification. The Peterson Guide ot Day-flying Hawks uses the drawings from this guide.

This guide has very good drawings on birds of prey. It guide illustrates several plumages and the sexes. The guide covers just the hawks (falcons, vultures, eagles, etc.) no owls are included. It is a thick little book just still small enough to fit in a pocket or day pack.
















Books for Preparation Before Going Birding

Hawks in Flight: The Flight Identification of North American Migrant RaptorsThis very thorough guide to the holistic approach. This book is meant to be read before going raptor watching. It includes all the diurnal (day- active) raptors. Night-active owls are not included. It focuses on each species distinct characteristics. Including movement, color pattern and body shape. It is not necessarily meant to be carried outdoors.

How to Spot Hawks and Eagles (How to Spot)
This natural history book which discusses the types of raptors and how they differ. It is full of excellent color photographs of the various raptors you will see at hawk watching lookouts or from your neighborhood. It is a book to read and study at home before you go into the field.

















Hawks from Every Angle: How to Identify Raptors In Flight
There are over 300 photos on 19 species of raptors including vultures. This book is for the experienced birder. These 300 photos cover every angle of the birds in flight and plumage.The beginning of the book provides good basic information on hawk migration and top sites to view it.

Spicebush Swallowtail Butterfly - Life Cycle

Spicebush Swallowtail adult

The adult Spicebush Swallowtail is a relatively long-lived butterfly. It is very common in the Philadelphia area. It is so large that it hard to miss.  

This species courts and mates in the afternoon. They mate in flight with the male hovering over the female. 

The eggs are plain and spherical and can be found on the species' host plants. Host plants are the plants that the larva is able to digest. Each species of butterfly has specific plants that it can eat. These are almost exclusively native plants.

Why should we plant native plants in our gardens?

young Spicebush Swallowtail larvae (caterpillar)

 The young larvae resembles a bird dropping. It feeds at night and lives in a folded-over leaf shelter. 

The mature caterpillar continues to feed at night and rest during the day.

The mature caterpillar has "snake head" eyespots. It lives in a silk-covered leaf tube. It will turn yellow before pupating. Two most common host plants are Spicebush and Sassafras.

Spicebush (Lindera benzoin)

The Spicebush blooms in early spring. The leaves which appear later feed Spicebush caterpillars. The Caterpillars fare better eating Spicebush leaves than Sassafras leaves. 

Sassafras tree (Sassafras albidum)

Spicebush Swallowtail chrysalis

After the caterpillar reaches it's full size, it creates a chrysalis. The chrysalis looks just like a dried leaf and hangs from a silken thread. This chrysalis is in the Butterfly house at Tyler Arboretum in Media, PA. 

Adult Spicebush Swallowtail

After changing form into a chrysalis, an adult butterfly emerges. A beautiful velvety Spicebush sips nectar from a Lantana plant. Butterflies can sip nectar from any nectar-producing plant that its' proboscises can navigate. It is the larval host plant that is so specific.


The metamorphosis of a butterfly has another example of "nature's magic". I hope after reading this you will be able to identify Spicebush Swallowtails.

Spicebush Swallowtail Butterfly Facts

Family: Papilionidae (Parnassians and Swallowtails) - Spicebush is one of the 12 Swallowtail species on the East Coast.

Range: Eastern United States. The species is declining in the far South. It is gone from the Florida Keys.

Wingspan: 3 1/2 - 4 1/2 inches across (89 - 114 mm)

Hostplant: Primarily SPicebush (lindera benzoin) but also Sassafras (Sassafras albidum) and bays. The larvae fare better on Spicebush than on Sassafras.

Habitat: Generalist - woods, woodland edges, roadsides, fields, swamps and parks.

Flight: low-flying, 3 - 9 feet above the ground with fairly rapid wing beats. The adults are strong fliers which can fly across sizable bodies of water.

Nectar: Adults have long proboscises which enable the butterfly to sip nectar from deep blossoms.

Eggs: Generally plain and spherical

Naturalist News - September 2010

In a few weeks, this female Ruby-throated Hummingbird will be migrating.

Here in Philadelphia...
September is a wonderful time in Philadelphia. The days and nights are cooler. And the trees begin to turn luscious colors.

In this issue of our e-mail newsletter the focus is on planning for trips to see the great migrations. The Philadelphia area is just the place to see the migration of birds of prey, Monarch butterflies and neotropical birds, like warblers, returning to their winter homes further south.

Migrations in this area will last into November. But, don't wait to the last minute to plan a trip. Your local Audubon Society most likely has trips to see bird migrations in the area. These trips are usually open to the public to come along.


Natural History to Read

"The Migration of Birds"
http://www.npwrc.usgs.gov/resource/birds/migratio/routes.htm

Hawk Mountain's Guide to Raptor Watching - don't miss the "Best Times to See Raptors", it  is useful in timing trips.
http://hawkmountain.org/Raptor_Migration.php#best%20dates

Day Trips to See Migrations in the Philadelphia Area

Hawk Mountain and Bake Oven Knob
Hawk Mountain is a word famous site for watching raptors. People come from all over the world to observe and study on the mountain. It is located along the Kittatinny Mountain Range.

Cape May Point State Park
One of my favorite places is a great place to watch the migration of raptors, other birds, dragonflies and Monarch butterflies. Cape May, NJ is one of the premier places to watch both spring and autumn migrations.

Fort Washington State Park
All 16 of the raptors species that fly through Hawk Mountain also fly through Fort Washington State Park. At this park just outside of Philadelphia watch the raptors sail overhead, without the long drive!
There is a hawk watching platform with volunteers on duty daily. The hawk watch starts September 1 and runs through October 31. Militia Hill Hawk Watch http://www.wyncoteaudubon.org/mhhw.htm
Daily Hawk Count http://hawkcount.org/month_summary.php?rsite=423

Great Spangled Fritillary (Speyeri cybele) on Joe-Pye Weed.

Nature Calendar
September 8 - New Moon
September 15 - First Quarter Moon
September 22 - Autumnal Equinox, Fall officially begins
September 23 - Full Moon
September 23 - in Southern hemisphere - Vernal Equinox, Spring officially begins
September 30 - Last Quarter Moon


Resources


Audubon Pennsylvania  http://pa.audubon.org/index.html to find local chapters and their field trips.

Swamp Rose Mallow (Hibisus palustris) in bloom.

All photos and text copyright Donna L. Long, 2010.

Eastern Tiger Swallowtail on Purple Coneflower - Attracting Butterflies

Eastern Tiger Swallowtail (Papilio glaucus)

This Eastern Tiger Swallowtail went to on a feeding frenzy. I would have thought that this dried and spent flower head would have had nothing left except seeds. But this butterfly obviously found something to flip over. 

Yet, another reason to leave spent flower heads standing.  They attract both birds and butterflies. Those spent blossoms can provide nectar and seeds for birds.