Snowy Owls Arriving & Christmas Bird Count Dates

Nature Notes for November 24, 2017

“There’s a Snowy Owl on the roof of the house across the street.” said the voice on the telephone last Sunday. The caller was excited enough that I had to ask, “What street?” It was only a few blocks away, so my husband and I jumped into the car to look for it. (It’s not difficult to distract us from yard clean-up.)

We found the bird without difficulty and had a good look through binoculars. Unlike the two Snowy Owls that had turned up at Cobourg Harbour breakwater the week before, a spotting scope was not necessary to have a good look. At least one Snowy has also been reported from Presqu’ile this week.

There seems to be an irruption of Snowy Owls into southern latitudes this year.

Photo © Rob Lonsberry Photography

 Why this bird had chosen to land in a built-up part of town is a mystery. There didn’t seem to be any obvious hunting area there. Perhaps the bird was just tired from bucking the wind. Because Snowy Owls nest in the Arctic, where there is no night in the summer, they are as apt to be active in the daytime as at night.

Snowy Owls are an irruptive species. That is, they sometimes move out of their regular range in search of food. In the case of the owls, a high population of lemmings on the breeding ground may lead to more young birds than usual being raised. When winter comes there may not be enough food for all these birds. Some of the Snowy Owls will irrupt south in search of food.

In the south, Snowy Owls eat rodents, rabbits and many wintering ducks and gulls. Some spend a lot of time on the edge of the ice in the Great Lakes in order to hunt ducks. Four years ago, when there was a massive irruption of Snowy Owls into the south, the Ontario Ministry of Natural Resources was collecting owl pellets to determine just what the owls were eating. Pellets are the undigested parts of the prey – bones, fur, feathers – that the owls cough up. Many pellets can often be found around favourite roosts. By dissecting the pellets, the prey can be identified. I never heard the results of the MNR study.

That same winter, 20013/14, saw an irruption of Snowy Owls to the south like no one had observed in 50 years. This led to the formation of Project SNOWstorm, a group of scientists who decided to take advantage of this event to study the birds. (SNOW is the code that bird banders use for Snowy Owl.) They teamed up with an IT team to create a small GPS transmitter which an owl could wear on a harness. These small devices are powered by a solar battery. Last winter’s cloudy weather did slow the units a bit, since they never fully charged. As long as the owl was within range of a cellphone tower, the information could be retrieved.

The transmitters have evolved since that first year to be lighter and collect more data. Many remote northern communities have been installing cellphone towers, which has helped in the retrieval of data from the north. However, these amazing machines can store data. If an owl returns to the south in a subsequent winter, the data from the previous summer can be downloaded. A number of the birds have come back south

Although some of the people involved in Project SNOWstorm are professional biologist, for this project they are volunteering their time. There are many avocational biologists involved, too. The project has been funded by crowdfunding and by donations from naturalist groups.

Just this week, I received two posts from Project SNOWstorm. Snowy Owls are returning to the south in higher than usual numbers and they are anticipating a large irruption. To follow the project, check out http://www.projectsnowstorm.org/

Remember to carry your binoculars if you go for a walk by Cobourg Harbour. You may find a Snowy  yourself.

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Before the December column is published, several Christmas Bird Counts will have been held. There are three in Northumberland County, dates as follows:

●Port Hope-Cobourg CBC, Sat., Dec. 16, 2017

●Presqu’ile-Brighton CBC, Sun., Dec. 17, 2017

●Rice Lake Plains CBC, Mon., Jan. 1, 2018

Christmas Bird Counts are not actually held on Christmas Day, but from December 14 to January 5. Each count covers a specific geographic area. For more information about Christmas Bird Counts, go to http://www.birdscanada.org/volunteer/cbc/.

Project FeederWatch Season Begins

Nature Notes for October 27, 2017

Sometime during the week of November 11, you will find me, on two consecutive days in the rocking chair in my living room that overlooks the garden and my bird feeders. I will be counting the number of birds of each species that visit my feeder.

I know that more than 20,000 people throughout Canada and the continental U.S. will also be counting birds. We are all participating in Project FeederWatch, which this year runs from November 11, 2017 to April 13, 2018. This is a winter bird survey using an army of volunteers, called Citizen Scientists, to collect data in a systemic way.

Dark-eyed Juncos are one of the birds commonly seen in winter at my feeder.

Photo © Rob Lonsberry Photography

 What surprises might this winter bring? Just last winter, for the first time in twenty years, a Northern Flicker was a regular at our feeder. Most flickers migrate out of southern Ontario in winter, so this was a treat. One year, a Chipping Sparrow spent most of the winter at the feeder, until some time in April, there were two Chipping Sparrows. For a number of years, a female Pileated Woodpecker visited our peanut feeder. My peanut feeder has sometimes been visited by a Carolina Wren. This species is at the north edge of its range in Northumberland. There are often a few White-throated Sparrows that come and go and feed with the Dark-eyed Juncos.

Sometimes, there are large numbers of one species. When northern finches such as Pine Siskin and Common Redpoll irrupt south, they may mob the feeder and niger seed will disappear before one’s eyes. The prediction is for a big flight of finches this winter, so be prepared to spend a lot on niger and black oil sunflower seeds.

Project FeederWatch began in Ontario in 1976 when Dr. Erica Dunn of Long Point Bird Observatory started the Ontario Bird Feeder Survey. By the winter of 1987-88, the project had evolved into Project FeederWatch and was jointly organized by Bird Studies Canada and Cornell Lab of Ornithology.

The massive amounts of data collected by FeederWatchers across the continent help scientists understand:

●long-term trends in bird distribution and abundance

●the timing and extent of winter irruptions of winter finches and other species.

●expansions or contractions in the winter ranges of feeder birds

●the kinds of foods and environmental factors that attract birds

●how disease is spread among birds that visit feeders

FeederWatch data is regularly published in scientific journals, regional birding and nature newsletters, national magazines and newspapers continent wide.

Anyone who runs a bird feeder and would like to take the time to learn their backyard birds can participate. In Canada, participants register through a membership in Bird Studies Canada. Participants will be sent a kit which contains, along with data sheets and instructions, a colour poster of common feeder birds. I have mounted this poster and have it hanging in the kitchen. I have seen all but one of the birds illustrated at my feeder over the years. There is a special kit for use by classroom teachers or homeschoolers.

The species most commonly found at feeders in Ontario in the 2016-17 season was Black-capped Chickadee, followed by Downy Woodpecker, Dark-eyed Junco, American Goldfinch and White-breasted Nuthatch.

For more information about this project or to sign up as a Citizen Scientist, go to feederwatch.org. Perhaps you will be surprised by the visitors to your yard.

Monarch Butterflies moving south

Nature Notes for September 29, 2017           

On September 20, the photo below popped up on my Facebook page, with the note: “Stopped in my yard for a slurp”. While I am often treated to Jean Huffman’s photos of flowers and six- and eight-legged creatures that inhabit her yard, this one was special. This Monarch butterfly was tagged. 

 Tagged Monarch visited my neighbour's garden

photo © Jean Huffman

Thanks to the magic of Facebook, I soon learned that this butterfly had been tagged the previous day at C.R. Gummow Public School in Cobourg by teacher Laurel Merriam. The overnight trip from Cobourg to Port Hope was only the beginning of the butterfly’s journey. It was taking advantage of the flowers in Jean’s garden to put on fat for the long trip ahead. It is possible that it might journey as far as the Michoacan mountains of Mexico where all the Monarchs from east of Rockies spend the winter.

Monarchs have been much more abundant this year than for several years. In the past few weeks, it has been common to see hundreds of them migrating and nectaring on the goldenrod and asters along the lakeshore. Last Sunday, my husband observed over 300 around the A.K. Sculthorpe Marsh in about 1.5 hour. This long stretch of hot, dry weather, so late in the fall, has probably been of benefit to the butterflies. This weather has allowed larvae that otherwise might not have matured into adults to develop and migrate.

Most school children now know that Monarch butterflies migrate to Mexico. Dr. Fred Urquhart of the University of Toronto started to study Monarch migration in the 1930s. By 1940, he had developed a glue with which to affix small tags to a butterfly wing. The tag red "Send to Zoology University of Toronto Canada." He and his wife, Norah, tagged many butterflies, but eventually realized that they needed some help. In 1952 he enlisted the assistance of many Citizen Scientists, although they were probably not called that at the time.

Two local naturalists, Audrey Wilson of Cobourg and Ted McDonald of Port Hope, were among those early cooperators with the Urquharts' project.

Finally, in 1975 the wintering area was found. In January 1976, Dr. Urquhart himself retrieved in Mexico a butterfly that had been tagged in in August 1975 in Minnesota. This was confirmation of migration.

The Monarch Butterfly is listed as Endangered by the Committee on the Status of Endangered Wildlife in Canada. Tagging is one way to monitor population trends of this species. The tags have been modified slightly since the original Urquhart tags. To my eye they look like a small Avery label. If readers are interested in participating in this project, there is information at www.monarchwatch.org.

Another species of butterfly that migrates is the Painted Lady. Many of these have also been observed recently. On the same day that he counted many Monarchs, my husband counted 60 Painted Ladies. This species, which occurs on all continents except Australia and Antarctica, has been the object of study by a team from the University of York in the U.K. Their findings were published in 2012 in the journal Ecography.

Through a combination of Citizen Scientist reports and radar, it was discovered that Painted Ladies do not simply die in the fall when the weather turns cold. They migrate south again, but at an average altitude of 500 meters. This is so high that the butterflies are out of view of observers on the ground.

Unlike Monarch butterflies which winter in one relatively small area, Painted Ladies travel and continue to breed throughout their migration route. They travel from tropical Africa to the Arctic Circle and back to Africa in the fall. The butterflies that return to Africa are several generations removed from their ancestors that left Africa the previous autumn.

I know of no similar studies of the Painted Ladies of North America. Other North American butterflies that migrate and occur in our area include Red Admirals, American Lady, Question Mark, Common Buckeye and Orange Sulphur. Perhaps there is a study waiting for a researcher on one of the other migrants.

For more information about Monarch butterfly projects involving Citizen Scientists, go to www.monarchwatch.org.

Common Nighthawks on the Move

Nature Notes for August 25, 2017

Just as the light is fading so that nothing is very clear, readers may see a bird with a fluttery flight passing overhead. This bird will appear as a dark silhouette with an obvious white bar on each wing. It has long, pointed wings and a long notched tail. The flight style is reminiscent of a bat, although the bird is larger than a robin.

Common Nighthawks may be seen in late August as they migrate south.

Photo © Rob Lonsberry Photography

This is the time of year when Common Nighthawks are moving south from their breeding grounds to South America where they spend the winter. Common Nighthawks breed throughout North America and into Central America.

Despite their name, they are not hawks at all, but member of the nightjar family, another odd name. At one time, they were called “goatsuckers” because of a myth that they entered barns at night and sucked goats milk.

They are a mottled brown, tan, white, and black, the perfect coloration to blend into the background when they roost and nest on the ground.

Their preferred nest sites are open, vegetation-free habitats, including dunes, beaches, recently harvested forests, burnt-over areas, logged areas, rocky outcrops, rocky barrens, grasslands, pastures, peat bogs, marshes, lakeshores and river banks. In Northumberland County, they nest in open areas of the Northumberland and Ganaraska Forests.

When we were in Saskatchewan last summer, we found them roosting on fence posts during the day at Old-Man-On-His-Back Nature Reserve. We had never seen them do this anywhere in the east.

In urban areas, they will nest on flat gravel roofs. Unfortunately for the nighthawks, the urban crows and gulls have discovered this and often depredate the nests. A nighthawk eggs is a good meal for a crow.

Common Nighthawks don’t build a nest. They usually lay two eggs which are laid directly on the ground. The young don’t stay long around the nest.

Since Common Nighthawks are active only at dawn and dusk, when visibility is poor, and they are very cryptically coloured, they are very hard to study. Both Ontario Breeding Bird Atlases commented on how difficult it was to confirm nesting of this species.

In the spring, they can often be found by their vocalisations, a “peent” given in flight. In the spring, the male has a spectacular display. He calls, circles and “booms” as he swoops down over his potential mate. The booming is caused by air passing through his vibrating primaries.

Common Nighthawks are aerial foragers. They east almost exclusively flying insects – moths, mosquitoes, flying ants – and can sometimes be seen hunting under street lights. Although their beaks aren’t very big, when they open their mouths, they have a huge gape. This is an excellent adaptation for scooping up insects from the air.

Unfortunately, like all aerial foragers, their population seems to be declining. It is listed as of “Special Concern” by Species at Risk in Ontario and as “Threatened” by Committee on the Status of Endangered Wildlife in Canada.

The causes of the decline of Common Nighthawk populations are unknown. It may be related to the decline of the insect populations on which this species preys. Other factors that may have contributed to the declines probably include habitat loss and modification. The increased predator population (specifically Domestic Cats, Striped Skunks, Raccoons, American Crows, and Common Ravens) may contribute to this species’ decline, particularly in urban areas. Other possible factors include collisions with motor vehicles and climate change.

Although Common Nighthawks do not occur in as large numbers as in the past, readers still have a good chance of seeing some in the evening as they migrate towards South America.