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Wednesday, October 19, 2011

Still on the Move

Now that we are well into autumn, migration is in full swing. Many creatures headed south weeks ago. Among the first were the tree swallows. Think back to the last days of August and you might recall seeing many dozens of swallows lined up on phone lines as they prepared to leave for points south. Another traveler is the common nighthawk. I remember watching and hearing nighthawks when I was growing up. These would be found in most small cities throughout our area during the summer nesting season. Their numbers have seriously declined over the last several decades. Nowadays I look forward to seeing them at dusk as they migrate southward during the late days of August and the first days of September.

One of the greatest spectacles of migration is the movement of broad-winged hawks from their summer nesting homes in the forests of the northeast to their winter haunts in South America. The broad-wings leave en masse at the end of August through to the end of September, after which very few will be seen until next spring. To conserve energy on their long flight south, they typically soar upward in thermal updrafts or winds deflecting off mountain ridges. As they glide up on the lifting wind they look to the south and when they observe other hawks spiraling upward they glide off to another updraft. In this manner they travel several hundred miles each day with hardly any flapping of their wings thus conserving energy. These groups of hawks form a boiling mass of birds that is given the name “kettle.” The largest kettle I have ever observed was about three hundred hawks. Some kettles have been seen with thousands of hawks. The prime time to see broad-winged hawk kettles is the middle of September. Two organization you can check out to learn more about hawks in migration are the Hawk Migration Association of North America (HMANA) at www.hmana.org and NorthEast Hawk Watch at www.battaly.com/nehm/. Look to the right and you will find links to both organizations.

There are two other amazing migrants that we have the chance to observe in our fall skies: the monarch butterfly and the ruby-throated hummingbird. The ruby-throat travels to Central and South America. These small birds waste very little time as they move south. All you see is a glimpse of them as they buzz through just above the tree tops. It is amazing that this small bird can make long distance journeys, sometimes traveling hundreds of miles over oceans with no place to stop for rest or food. I came across a very interesting article online by Bill Hilton, Jr., an ornithologist specializing in hummingbird studies. He describes the work ornithologists have done, including his own, to discover the secrets of hummingbird migration. You can find this article online at http://www.hiltonpond.org/articlehummermigrationmain.html or click on link to the right.

The other well-known migrant is the monarch butterfly. Monarch migration starts at the end of August and lasts until early October. The butterflies that pass us on their way south are ones that hatched and grew up here in the northern latitudes. They never see their parents (not unusual for insects). These insects begin life as an egg on a milkweed leaf. They hatch and grow, undergoing metamorphosis, then travel by themselves on a southward journey to Mexico. All the monarchs in eastern North America travel to the same forests in the Sierra Madre Mountains of south western Mexico. How they know how and where to go on this long journey, no one knows.

To make the story even more interesting, the monarchs we see leaving the Northeast will never return here. Rather, it is their great-great-great grandchildren that will return. Butterflies that grew up here will make their way to Mexico and live there for the winter. In early March they will start the trip northward, but they will never make it back. They will have reached the end of their life, torn and tattered from the long migration and their daily efforts at survival: searching for food and shelter, avoiding predators and surviving dangers like the ravages of wind and rain. But before they die, the females will lay eggs. These eggs will hatch and grow into butterflies that will continue their journey north. But even this next generation will not make it all the way. It will take another two generations of monarchs to make it back here to the Northeast. It will be mid-summer before we see these beautiful butterflies once again.

This marvel of migration is enjoyed and studied by many people. Generally speaking, most of the interest centers on the hawks, though many hawk watchers will record the numbers of monarch butterflies they see flying by. Throughout North America there are hawk migration sites where people gather to watch and count hawks as they soar past. The most famous site is Hawk Mountain along the Kittatinny Ridge in Pennsylvania. There is a hawk watch site outside Albany, NY along the Helderberg Escarpment at Thatcher State Park, and I just learned of a hawk watch on Mount Peter in southern Orange County, NY. This site is purported to be the third oldest hawk watch site in the east and is staffed by volunteer observers. I spent time this past September observing hawks, monarchs and hummingbirds at each of these sites. Here is what I saw.


My observations at Thatcher Park, September 12-14, 2011

Broad-winged Hawk - Sept 12 - 144, Sept 13 - 57, Sept 14 - 28, Total for the three days - 229

Monarch butterfly - Sept 12 - 28, Sept 13 - 46, Sept 14 - 30, Total for the three days - 104

Ruby-throated Hummingbird - Sept 12 - 4, Sept 13 - 0, Sept 14 - 1, Total for the three days - 5

Other Raptors

Bald Eagle - Sept 12 - 4, Sept 13 - 1, Sept 14 - 0, Total for the three days - 5

Golden Eagle - Sept 12 - 1, Sept 13 - 0, Sept 14 - 0, Total for the three days - 1

Sharp-shinned Hawk - Sept 12 - 3, Sept 13 - 0, Sept 14 - 2, Total for the three days - 5

Coopers Hawk - Sept 12 - 2, Sept 13 - 1, Sept 14 - 0, Total for the three days - 3

American Kestrel - Sept 12 - 2, Sept 13 - 1, Sept 14 - 1, Total for the three days - 4

Merlin - Sept 12 - 1, Sept 13 - 0, Sept 14 - 0, Total for the three days - 1

Osprey - Sept 12 - 2, Sept 13 - 2, Sept 14 - 0, Total for the three days - 4

Northern Harrier - Sept 12 - 1, Sept 13 - 1, Sept 14 - 0, Total for the three days - 2

Unidentified Accipiter - Sept 12 - 2, Sept 13 - 3, Sept 14 - 1, Total for the three days - 6

Unidentified Buteo - Sept 12 - 0, Sept 13 - 0, Sept 14 - 1, Total for the three days - 1

Unidentified Falcon - Sept 12 - 0, Sept 13 - 1, Sept 14 - 0, Total for the three days - 1

Unidentified Raptor - Sept 12 - 1, Sept 13 - 2, Sept 14 - 0, Total for the three days - 3


My observations at Mt. Peter, Orange County, NY, September 16, 2011

Broad-winged Hawk 661

Monarch butterfly 361

Ruby-throated Hummingbird 0

Other Raptors

Bald Eagle 11

Golden Eagle 0

Sharp-shinned Hawk 35

Coopers Hawk 5

American Kestrel 14

Merlin 0

Osprey 11

Northern Harrier 1

Unidentified Accipiter 5

Unidentified Buteo 2

Unidentified Falcon 2

Unidentified Raptor 1

The most amazing observation at Mt. Peter’s was the movement of monarch Butterflies. I was at the site from 9:00 in the morning until 5:30 in the evening. During the day, from 9 until 4 we had seen 116 with the majority of those in the afternoon hours. Then from 4 until 5:30 245 monarchs flew by. I have never before seen so many monarchs in such a short period of time. It was like a river of butterflies flowing past. I wonder what conditions created such an amazing spectacle.

While at Hawk Mountain on September 17th I observed several thousand broad-winged hawks in migration. Hawk Mountain posts their observations online at www.hawkmountain.org or clink on link to the right.


Monarch Butterflies observed at Sapphire Elementary School, Monroe, NY, September 19-23, 2011

Monday, Sept 19

10:00-11:00 with Mr. Costa’s class – 3

12:00-1:00 with Mrs. Buonamano’s class – 4

1:00-2:00 with Mrs. Rende’s class – 2

Tuesday, Sept 20

Rainy weather no monarchs observed

Wednesday, Sept 21

10:00-11:00 with Mrs. Zuzek’s class – 5

1:00-2:00 with Mrs. Cassese’s class – 2

Thursday, Sept 22

9:00-10:00 with Mrs. Teel’s class – 1

11:00-12:00 with Mrs. Janeczko’s class – 12

12:00-12:30 during my lunch – 1

12:30-1:30 with Mrs. Cahill’s class – 2

1:30-2:30 with Mrs. McNamara’s class – 3

Friday, Sept 23

Rainy weather no monarchs observed


Monarch Butterflies observed at Smith Clove Elementary School, Central Valley, NY, October 11-14, 2011

Tuesday, Oct 11

9:00-10:00 with Mrs. Rojas’s class – 5

10:00-11:00 with Mrs. Quintana’s class – 7

11:00-12:00 with Mrs. Dell-Webster’s class – 7

12:00-1:00 during lunch – 1

1:00-2:00 with Mrs. Apostolico’s class – 3

Wednesday and Thursday, the 12th and 13th were rainy days with no observations made

Friday, Oct 14

8:00-9:00 upon arrival as school – 1

10:00-11:00 with Mrs. O’Dowd’s class – 1


I encourage any class that has the chance to observe monarch Butterflies to record their numbers and e-mail them to me. You can take time to observe monarchs during recess or give students a reward for their hard work by going outside to specifically look for monarchs. Record the time at which the observations were made, the weather conditions and wind direction. Encourage students to be careful in their observations, you don’t want to count the same butterfly twice. Watch carefully to see that the monarch has moved on. If you see another monarch 5 or 10 minutes later you can be assured that it is a different butterfly. Once a butterfly has moved on it is not likely to circle back, after all they are on their way to Mexico. I will keep a track of these observations post them periodically and gladly answer any questions you might have about migration and these amazing migrants.