Northern Saw-whet Owl visits Suburban Garden

Nature Notes for October 30, 2015

“There’s a small owl on my deck. It’s been there for a couple of hours. What is it doing there? Do you think it’s all right?” said the worried voice on the telephone.

The first questions I asked were to try to identify the owl species: How big is it? Does it have ear tufts? Since it was described as quite small and without ear tufts, my best guess was that it was a Northern Saw-whet Owl.

These tiny owls weigh between 80 and 100 grams. As with all owls, the females are larger than the males. Because of its small size, many people describe it as a “baby owl”, but that’s a big as they get.

Northern Saw-whets are one of the few owl species occurring in this area that migrate regularly. Some other owl species irrupt south in some winters, usually due a shortage of food at more northern latitudes. Saw-whets, however, migrate south in winter and back north again in the spring. If the hunting is good, a few will stay around in Northumberland County through the winter. There have been recoveries of saw-whets, banded in Northumberland, from as far south as southern Virginia.

These little owls are highly nocturnal so they are seldom seen by observers. During the day, these owls roost in dense cover, so they are difficult to detect. There is a sub-set of bird banders that become nocturnal during the migration period in order to capture and band saw-whets. Much of the knowledge of their biology, including migration routes, comes from these studies.

Early settlers gave this owl its curious name because they thought the song was like the sound of a saw being whetted or sharpened. It has a repetitive one-note song, which it sings in the early spring (late February to early April), around the time the maple syrup is running.

Saw-whet owls nest in tree cavities and will use nest boxes.

So what was the bird doing in a Cobourg backyard in the daytime? It was probably trying to keep as still as possible, to avoid being prey for larger birds. Even at night, saw-whets can be at risk, since big owls will eat little owls if they get a chance.

A neighbouring backyard had bird feeders. Perhaps the saw-whet was waiting for an opportunity to feed, too. They do prey on small birds. Often, the spilled seed from bird feeders attracts small rodents which would also be the perfect size of prey for a saw-whet owl.

A few years, ago, our garden was visited by a saw-whet owl in the spring. In the pre-dawn light, it tried to attack a Mourning Dove under the feeder, but was unsuccessful. Later in the morning, our attention was drawn to its roosting place by a flock of scolding chickadees. This bird spent half the day in the yard and delighted several visitors.

Although a few Northern Saw-whet Owls nest locally, most are hatched from nests in the boreal forest. It is possible that this stop in Cobourg was the bird’s first encounter with people. It didn’t yet know that it might be wise to be cautious around humans.

The Project FeederWatch season begins on November 14, 2015. For more information, go to www.birdscanada.org/feederwatch.

Warblers Grounded by Rainy Weather

Nature Notes for October 2, 2015

As I write (on Tuesday, September 29), it is raining. A Nashville Warbler, a Tennessee Warbler and a Black-throated Green Warbler have taken refuge in my garden.

The weather was quite nasty on September 12 and 13. A cold rain was falling for most of the weekend, accompanied by a low cloud ceiling. Along the A.K. Sculthorpe Woodland Trail on Port Hope’s eastern waterfront, there was a grounding of small birds. A total of 24 species of wood warblers was seen over the weekend. The list included Tennessee Warbler, Orange-crowned Warbler, Nashville Warbler, Northern Parula, Yellow Warbler, Chestnut-sided Warbler, Magnolia Warbler, Cape May Warbler, Black-throated Blue Warbler, Yellow-rumped Warbler, Black-throated Green Warbler, Blackburnian Warbler, Pine Warbler, Palm Warbler, Bay-breasted Warbler, Blackpoll Warbler, Black-and-white Warbler, American Redstart, Ovenbird, Northern Waterthrush, Mourning Warbler, Common Yellowthroat, Wilson’s Warbler, and Canada Warbler. This is about all the expected warbler species for this time of year. 

 Wilson's Warbler

Blackburnian Warbler

 Magnolia Warbler

A small sample of the many warblers grounded recently in Port Hope

Photos © Rob Lonsberry Photography

This grounding consisted of hundreds of birds in this small area. The warblers were accompanied by several Red-eyed Vireos and Swainson’s Thrushes, as well as a single Gray-cheeked Thrush and a Veery. The first of the migrant sparrows was also present: Song Sparrow, Lincoln’s Sparrow, Swamp Sparrow and White-throated Sparrow. Several species of flycatchers were also included in the flocks of birds: Eastern Wood-pewee, Yellow-bellied Flycatcher, Least Flycatcher and Great Crested Flycatcher.

In rainy, stormy weather, small migrants are forced to land. In good weather, the birds would just keep going and many fewer would be seen on the ground.

They weren’t easy to spot. Small birds are very good at hiding behind leaves and branches. The smallest of the warblers weigh only about 8 grams. Observers also had to contend with raindrops fogging up optical gear and eye glasses, and dripping off the brims of hats.

Most small land birds migrate at night. It is thought that the darkness provides them some protection from hawks, which migrate by day. Winds tend to be calmer at night, so the birds don’t have to expend as much energy to fly. As well, they may navigate by the stars.

These little birds are on a long journey. Most have come from breeding grounds in the boreal forest of northern Canada and are travelling to Caribbean islands, Mexico, Central America or South America. It is difficult for humans to believe these long trips, without benefit of an airplane or the use of GPS units. The trip is fuelled only by millions of tiny insects, berries and seeds.

The fall migration takes place over a more protracted time period than that in the spring. There is not the same pressure to arrive at the breeding area and raise a family. As long as the birds have adequate food, they can take their time.

Most land birds start south in August, beginning with insect eating birds such as warblers and flycatchers. There is a big movement of warblers in late August and through September, while the latest migrant warbler, the Yellow-rumped Warbler, may be around until almost the end of October.

Seed-eating birds such as sparrows and finches usually begin their migration somewhat later. Most sparrows begin migrating in late September, but the peak of their passage is in mid-October.

Birding in the rain, although it may be miserable for the observers, can be quite exciting.

Birds in the Garden - August 2015

Nature Notes for August 28, 2015

For the past couple of weeks, my birding has been confined to my own yard, so this column reports on my observations there.

On August 9, I was wakened by a terrific racket of calling American Robins. They had found the chokecherry bush in my garden and declared the fruit ripe and tasty. Many of the robins had speckled breast which indicates that they were hatched this year. There were a few Cedar Waxwings also, but their very soft calls were drowned out by the robins. The robins were joined briefly by a Gray Catbird, Brown Thrasher and Northern Flicker. On the third day, a few European Starlings joined the feasting throng. 

The robins feasting in my garden were a bit older than the one in the photo, but many still had the speckled breast that indicates this year's young.

photo © Rob Lonsberry Photography

For three and a half days, the noise was constant.

Sometimes, a robin or a Blue Jay would come down to the deck to pick up the fallen fruit. A fearless chipmunk was also making use of the bounty. It would pick up a berry, eat the pulp off and stuff the pit in its cheek pouch. These berries are very, very tart (I’ve tried them.), but perhaps chipmunks like this taste. The pits were probably being stored by the chipmunk as winter food.

They suddenly, about noon on the fourth day, I became aware of silence. One glance at the chokecherry bush revealed the reason. Where there had been many plump berries, there were now only empty stems. Even most of the fallen berries had been cleared off the deck. Perhaps a raccoon had visited in the night when I wasn’t watching.

I expect a similar visit when the birds declare the fruit on my mountain ash tree ripe. The tree is loaded with fruit this year. In years of abundant fruit, sometimes the fruit will remain on the tree until the spring, when returning migrants devour it.

My hummingbird feeder is being regularly visited by probably more than one Ruby-throated Hummingbird. In my garden, hummingbirds use the feeder in the spring on their arrival back from migration and then I don’t see them for a while. They feed their young very small insects such as aphids, so aren’t as interested in the sugar water in the feeder during the nestling period.

They turn up again in August. Now, they are bulking up for their long southbound migration. Most hummingbirds will be gone from this area by the end of August. A few may hang around until later in the fall, but most will leave by Labour Day.

The peanut feeders are being visited regularly by several species of woodpeckers and many Black-capped Chickadees. It is difficult to tell exactly how many chickadees there are, but there seem to be at least three family groups of five or six birds each.

Both Downy and Hairy Woodpeckers are regularly feeding in the garden. The youngsters seem to be quite independent now. When they first arrived, the youngsters were obvious by their behaviour. The fledglings would land on the feeder, fluttering their wings and making begging noises until the adult took a peanut and stuffed it in their mouths.

There has also been a juvenile Red-bellied Woodpecker visiting the feeder. Although an adult pair has been seen regularly for several years, this is the first year that I remember a youngster visiting. It can be identified easily because it doesn’t have any red on its head yet. It usually announces its arrival by its clucking call.

Of course, where there are peanuts, there will be Blue Jays. They swoop in, with a great amount of fussing, and chase every other bird away from the feeder. They can’t hang on long to the tube feeder holding the peanuts, but they always manage to pull out a few nuts.

On the squirrel baffle under the feeder, I’ve often found the resident Song Sparrow. This bird has been spending a lot of time in the yard for about a month. It seems to have no head feathers. I’ve seen this problem in Blue Jays, Common Grackles and Northern Cardinals at this time of year, but this is the first time I’ve seen a bald Song Sparrow. The sparrow is feeding on the crumbs of peanut that have been knocked loose by the larger birds.

It is not necessary to go to some exotic location to observe birds and their behaviours. An excellent place to start is your own garden.

Merlins taking flight in Northumberland 2015

Nature Notes for July 31, 2015

“Ki-ki-ki-kee” sounded from outside my back window. The 2015 hatch of young Merlins have taken flight. Although they could be heard on a number of occasions in the west end of Port Hope, I never did find the nest this year.

Merlins are a small falcon, about the same size as an American Kestrel, but a bit bulkier. As with most birds of prey, the females are bigger than the males. Adult male Merlins have gray backs, streaked underparts and a banded tail. Adult females have brown backs. The young birds resemble the females in plumage. The dark “mustache” mark on the face is much less pronounced in Merlins than it is in other falcons.

 photo © Rob Lonsberry Photography

The name “Merlin” comes from esmerillon, the old French name for the species. Merlins used to be called “pigeon hawks” because in flight they look somewhat pigeon-like. Their species name, columbarius, is also a reference to pigeons.

Late 19^th and early 20^th records for Merlins in southern Ontario were mostly of migrating birds. At that time, this species nested primarily in the boreal forest.

During the 1950s and 1960s, Merlin populations plummeted due to exposure to DDT. This species was placed on the National Audubon Society’s Blue List from 1972 to 1981. By the mid-1980s, Merlins were showing some recovery, but were still not up to historic levels.

In the first Ontario Breeding Bird Atlas, the nesting range was shown as from Algonquin Park and north to the tree line. However, in the twenty years between atlases, the range of this species expanded southward and included urban sites as well as the boreal wilderness. In fact, the second Ontario Breeding Bird Atlas reported that the probability of encountering Merlins in Ontario had increased 100%!

One of these records was in Port Hope, where a nesting pair was discovered on Bloomsgrove Avenue in April 2004. This pair had commandeered an old crow nest and was discovered while evicting the crows – quite a noisy event. The nest fledged two chicks that year.

A couple of years earlier, a Merlin pair had been discovered nesting at Presqu’ile Provincial Park. By 2005, Merlin nests were being discovered several places in Northumberland, in both Port Hope and Cobourg. They seem well established now.

Merlins do not build their own nests, but take over nests of crows, other raptors or sometimes squirrel dreys. They prefer to nest in coniferous trees, but there are records of nests on the ground. Although they usually nest in trees, they need open habitats adjacent to the nest in which to hunt.

Merlins prey primarily on other birds, so the presence of a nest is often detected by piles of feathers under the “plucking” perch. They are very ambitious in their choice of prey and will attack birds almost as big as themselves.

An increasing number of Merlins spend the winter in southern Ontario, but most migrate. Some of these travel as far south as South America.

Medieval falconers called Merlins “lady hawks”. They were used by European noblewomen for sport to hunt Skylarks. Merlins are still popular with falconers, who use them to hunt quarry that ranges from sparrow-sized to dove-sized.

According to banding records, the oldest known Merlin was at least 11 years, 11 months old. It was banded as an adult in New York in 1982 and recovered in New Brunswick in 1993.

Since the young are quite noisy this time of year, readers have a good chance of detecting a Merlin, if there was a nest in their area. Good luck in your search.