Field Journal 5 Migration

On April 7th I went birding from 1:10 to 2:45 in the forest and riparian habitats near the Malone central high school. The weather was excellent with a crystal clear sky and a west wind of about 10 miles per hour. The temperature was quite warm for early march at 54 degrees Fahrenheit.

We are fully into spring in northern New York with the last traces of winter disappearing as the last bits of snow and ice have melted. The birds which overwinter in the region have become very active but the spring migrants are just starting to arrive. Several species that I observed that stay year round include the American Crow, American Robin, Canada Goose and Black-capped Chickadee. All of these birds have to be capable of finding food during the winter when many sources of food are cut off or limited. They also have to be able to withstand the cold temperatures. The American Robin in particular undergoes behavioral changes to be able to survive the winter. During the spring and summer seasons robins forage on worms in the unfrozen soil alone. During the winter the robins will congregate around shared food resources such as fruit trees which they use to survive the winter. The black-capped Chickadee makes use of snags for shelter during the winter. In addition the birds which overwinter rather than migrating south are able to increase their fat reserves and insulation in anticipation of winter. Migration is a very costly process to undertake. It is energetically expensive and the mortality rate is often high due to poor weather. The species that overwinter have adapted to overcome the challenges of winter rather than undertaking a costly migration.

Facultative migrants which may migrate based on weather conditions such as moving a little farther south if winter conditions are very harsh or moving north if they are more mellow. In northern New York both Canada Geese and Song Sparrows could be considered faculative migrants. Individuals that live farther north will migrate south for the winter but in northern NY we are on the northern edge of the region in which they can overwinter. Canada Geese in particular rely on open water during the winter. With winter breaking quite early the Canada Geese who had traveled slightly south are now able to return north. In the case of Song Sparrows and other facultative migrants when food resources are unavailable during the harshest parts of winter they can be forced south. With warmer temperatures and reduced snowfall they can return. In particular the winters in northern New York are changing due to climate change. Periods of intense cold and winter conditions are more often broken up by extended thaws or warm periods during the winter. Facultative migrants are able to take advantage of these thaws moving south when the conditions worsen and returning north during the thaws and warm periods to take advantage of the available resources.

I unfortunately did not come across any obligate migrants. While it appears that winter is done past years are evidence that we could still receive a significant snowstorm. Obligate migrants who arrive here in early April are taking a gamble. If winter is done than they will have first dibs on resources and nesting sites. But in the event that we experience a sudden snowstorm or several days of cold temperatures the obligate migrants weakened by their migration will be very vulnerable.

I tallied up the distance some of the faculative migrants could potentially migrate during the winter. I came up with the rough numbers of 300 miles for Canada Geese, 210 miles for the Brown Creeper, 150 miles for the Mallards and 100 miles for the Dark-eyed Junco. These were pretty rough calculations but I would call them an educated guess. Mallards only overwinter in a small strip running NE up from Lake Ontario following the Saint Lawrence river north. Farther north into Canada above Malone and south into the Adirondacks the mallards migrate. But Malone appears to fall into a small band where they can overwinter.

Posted by tsshafer tsshafer, April 08, 2020 19:37

Observations

Photos / Sounds

No photos or sounds

What

Black-capped Chickadee Poecile atricapillus

Observer

tsshafer

Date

April 7, 2020

Photos / Sounds

No photos or sounds

What

American Crow Corvus brachyrhynchos

Observer

tsshafer

Date

April 7, 2020

Photos / Sounds

No photos or sounds

What

American Goldfinch Spinus tristis

Observer

tsshafer

Date

April 7, 2020

Photos / Sounds

No photos or sounds

What

Black-capped Chickadee Poecile atricapillus

Observer

tsshafer

Date

April 7, 2020

Photos / Sounds

No photos or sounds

What

Belted Kingfisher Megaceryle alcyon

Observer

tsshafer

Date

April 7, 2020

Photos / Sounds

Square

What

Red-tailed Hawk Buteo jamaicensis

Observer

tsshafer

Date

April 7, 2020

Photos / Sounds

No photos or sounds

What

Mallard Anas platyrhynchos

Observer

tsshafer

Date

April 7, 2020

Photos / Sounds

No photos or sounds

What

Goosander Mergus merganser

Observer

tsshafer

Date

April 7, 2020

Photos / Sounds

No photos or sounds

What

American Brown Creeper Certhia americana

Observer

tsshafer

Date

April 7, 2020

Photos / Sounds

Square

What

American Crow Corvus brachyrhynchos

Observer

tsshafer

Date

April 7, 2020

Photos / Sounds

No photos or sounds

What

American Robin Turdus migratorius

Observer

tsshafer

Date

April 7, 2020

Photos / Sounds

Square

What

American Robin Turdus migratorius

Observer

tsshafer

Date

April 7, 2020

Photos / Sounds

No photos or sounds

What

Dark-eyed Junco Junco hyemalis

Observer

tsshafer

Date

April 7, 2020

Photos / Sounds

Square

What

Canada Goose Branta canadensis

Observer

tsshafer

Date

April 7, 2020

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