Rice Lake Plains Butterfly Count 2014

Nature Notes for June 27, 2014

If, last Saturday, you encountered a group of people along a roadside staring at something invisible to the onlooker and laden with a butterfly net, you stumbled upon participants in the second official Rice Lake Plains Butterfly Count. Butterfly Count.  Regular readers will know about bird counts, but butterflies? This is another way that information about the natural world is collected.

Teams are assigned to a particular geographic area and fan out to try to find as many butterflies as they can. The ideal day is warm and sunny. Butterflies are not very active below a temperature of 20ºC.

The June 21 date was bit earlier than most butterfly counts in southern Ontario. The date was chosen to coincide with the flight season of the Mottled Duskywing, which has recently been listed as Endangered by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC).

Each butterfly species has a particular flight season, some having more than one flight during the warm months. Some, like the Mourning Cloak, have a very long flight season. They overwinter as adults, emerge with the first warm weather, and can still be found into September. Others, like the Mottled Duskywing have a short flight season, about six weeks from mid-May through June.

The Mottled Duskywing is not a particularly striking butterfly. It is small and dark with various shades of brown splotching. It does, as do many butterfly species, have very particular habitat requirements. The only food of the larva (the caterpillar stage) is New Jersey Tea, a small flowering shrub of the dry prairie/savannah habitat of the Rice Lake Plains.

Most school children are familiar with the life cycle of the Monarch butterfly whose larvae feed only on milkweed. Many other butterfly species are just as particular. The Monarch mimic, the Viceroy larvae feed on willows and poplars. Red Admiral and Milbert’s Tortoiseshell larvae feed on stinging nettle. Baltimore Checkerspot feed on turtlehead (That is the name of a plant.) CommonBuckeye feeds on toadflax and snapdragon. Black Swallowtail feed on members of the parsley family, including garden carrots. Quite a number of species feed on a variety of grasses.

  One of many Northern Crescents seen on the count

photo © Rod Lee

Locating the larval food plants will indicate the likelihood of finding the butterfly at the right flight season.

The adult butterflies are often found nectaring on flowers. Last weekend was a bit early for too many flowers to be in bloom, but roadside patches of vetch and viper’s bugloss usually yielded a few butterflies. Often, butterflies are found on patches of damp ground where they suck up dissolved minerals. Another place to look for them is on animal scat. This doesn’t provide the most picturesque background, but the butterflies also obtain nutrients for this source.

How did we do on the count? The group’s tally was 39 species. Five Mottled Duskywings were seen. The most abundant species was Common Ringlet, with 327 individuals seen.

 Common Ringlet, the most abundant of the butterflies seen on this count.

photo © Rod Lee

Only two Monarchs were seen by the group. This species should have arrived back from Mexico by this date. Only time will tell whether this species’ eastern population will survive.

Perhaps some readers will study their butterflies over the summer so that they might take part in the 2015 Rice Lake Plains Butterfly Count, scheduled for June 2015. The count was sponsored by the Rice Lake Plains Joint Initiative and organized by the Peterborough Office of the Nature Conservancy of Canada.

Thousands of Dunlin visit Cobourg Harbour

Nature Notes for May 30, 2014

“Want to see a couple thousand Dunlin?” My husband greeted me with this question when he came in from work last Monday evening.

“Where?” I responded.

“Cobourg Harbour” he replied, “but there are none in Port Hope. I checked.”

Off we went to Cobourg. Away from the Atlantic coast, I don’t think that I have ever seen so many shorebirds. They lined the sand beach on the west side of the harbour, perched on the rocks of the breakwater and fed in several large flocks on the surrounding lawns. All were feeding furiously on midges. Joggers and walkers didn’t seem to bother them. They would fly up, wheel around and then settle back to eating. If one stood still, they would approach your feet.

Some of the thousands of Dunlin that visited Cobourg Harbour last weekend.

Photo © Rob Lonsberry

Dunlins are medium sized shorebirds. In breeding plumage, which they are wearing now, they have a gray face, rust coloured back and a large black patch on the belly. They have a relatively long bill, black and with a slight droop at the tip.

Close up of a single Dunlin

Photo © Rob Lonsberry

As with many shorebirds, it is necessary to learn them in several plumages. The juveniles are different from the breeding adults, which are different than the non-breeding adults. The same Dunlin migrating back south in early summer will look quite different than the ones seen this week in Cobourg Harbour.

Dunlins are a circumpolar species, occurring in Europe and Asia as well as in North America. The birds that were visiting Cobourg are probably the population that winters from the mid-Atlantic states in the U.S. to the Gulf of Mexico. This is further north than many shorebirds. Many other shorebirds travel to South America for the winter months.

These birds are en route to the tundra, where they will nest. The abundance of insects there provides lots of food on which to raise the young. Dunlins eat mostly insects, although they also feed on aquatic invertebrates.

The big flocks of Dunlin were first reported in Cobourg Harbour on Sunday, May 25. On that date, they were accompanied by a single Red-necked Phalarope, one Whimbrel, and a few each of Short-billed Dowitchers, Red Knot, Ruddy Turnstone, Sanderling and some “peeps”. Most of the latter were Semipalmated Sandpipers, although there was one Baird’s Sandpiper, a very unusual bird for the spring in Ontario.

On Monday, there were still about 2000 Dunlin, many Ruddy Turnstones, many Semipalmated Sandpipers and a few Whimbrel and Red Knots.

The birds came and went throughout the day. On several visits throughout a day, the mix of species could be quite different, although this week they were dominated by Dunlin.

Before we left Cobourg Harbour, several Dunlin flocks lifted off and headed north. We didn’t visit on Tuesday, but probably there were very few shorebirds left. Why they chose to visit Cobourg this week is a mystery. We could only enjoy the sight.

Northern Flickers Arrive

Nature Notes for April 25, 2014

What’s the bird I’m seeing on my lawn? It has a long beak, a black stripe across its chest and some red on the head?

Several times in the past couple of weeks I’ve had a variation of this query. After asking additional questions and showing the questioner the picture in a field guide, it was determined that the bird was a Northern Flicker.

There are a few additional features that would have made identification easier. First would be the size of the bird. It’s a bit bigger than a Blue Jay, so it is a rather large woodpecker. The back is brown speckled with black, the face is shades of gray or brown with the red (in the male only) a distinct spot on the nape of the neck. The male also has a black mustache stripe. In flight, flickers show a large white patch on the rump.

The wing lining of most flickers seen locally is bright yellow. This is also often seen clearly in flight. The western form of the Northern Flickers has red wing linings. For a time, they were considered separate species, Yellow-shafted and Red-Shafted Flickers. At present, they are considered two subspecies of the same species.

The French name for this woodpecker is pic flamboyant (flamboyant woodpecker), which I think is quite appropriate for such a colourful bird.

Northern Flickers spend much more time on the ground than most other woodpeckers. This can make it a bit difficult to find in a field guide, since most of the illustrations picture the woodpeckers clinging to the side of a tree in an upright position. Flickers are very fond of ants and probe into the ground to get at both ant adults and larvae. They commonly feed on lawns and other open areas with short vegetation. I have sometimes seen the holes poked into bare sandy soil by these birds. It took me a while to figure out what was making the holes.

While a few Northern Flickers may be present throughout the winter in Ontario, most migrate further south to winter in the continental U.S. During the past couple of weeks, they have been quite conspicuous as they have been returning.

Immediately on their return, the males start to stake out territories. Good dead snags are sometimes not in abundant supply. Like all woodpeckers, they nest in holes that they have created in trees that have dead stubs or soft centres to the trunk.

Flickers usually excavate a new nest cavity every year. (The old cavities are used by many other animals – European Starlings, squirrels, raccoons, Eastern ScreechOwls, Northern Saw-whet Owls to name a few.) The nest consists of a hole in a tree stub, with a tunnel curving downwards. Some wood chips will be left in the bottom of the cavity to cradle the eggs.

Because flickers do not have a beautiful song, they stake their territories by drumming an anything that makes a good noise. In addition to hollow trees, this can include metal chimney liners and the metal pipe venting a gas furnace. This sometimes causes some alarm in the residents of the houses used as drumming posts. The birds often start drumming quite early in the morning, so this can be nuisance.

Although they don’t sing, they do make very loud calls. Their “wicka-wicka-wicka” can go on for long periods of time. One source I consulted rendered this call as “waken-waken-waken”, perhaps a suitable rendering if it is being uttered at dawn around your house!

Once a nest hole has been excavated and incubation begins, the birds are much quieter. They don’t want to draw the attention of potential predators to the nest cavity.

Although Northern Flickers are not on any “watch list”, there was a substantial decline in their numbers in the twenty years between the two Ontario Breeding Bird Atlases. This is probably due to habitat loss. Many hedgerows that might have provided suitable nest trees have been cleared away, leaving fewer trees of suitable size for this bird to use as nest cavities.

They tend to nest in trees adjacent to open areas. Readers may be lucky enough to find one nesting near their home and feeding on the lawn.

Spring Migration at Last!

Nature Notes for March 28, 2014

At last, there has been some migration. The northward movement of birds is finally heralding the coming of spring. Since I usually write this column on Tuesday and it doesn’t appear in print until Friday, a sudden change in temperature (warmer) and wind direction (southerly) could cause a dramatic change in the bird species present in the area.

Although returning American Robins do indicate spring, the return of Red-winged Blackbirds is a much better indicator. The first one reported to me was on March 17, almost three weeks later than they are expected in this area. In the following week, many people were reporting Red-wings. Snow on March 19 may have caused a bit of reverse migration, since many fewer Red-winged Blackbirds seemed to be present late last week.

Along with the Red-wings came the first CommonGrackles. Although many people don’t like them, now, they, too, are a welcome sign of spring.

By the end of last week, a few Song Sparrows had arrived. On the other hand, the American Tree Sparrows will soon be thinning out as they move north to the Arctic where they breed. Last week, a few could be heard singing their sweet song along the Waterfront Trail in Port Hope.

On a walk around my neighbourhood this week, I could hear the trilly song of a Dark-eyed Junco. Although a few breed in the Northumberland Forest, most of these migrate a little further north to the Canadian Shield to nest.

Presqu’ile Provincial Park’s Waterfowl Festival was the weekend of March 15 and 16. This year, this date was a bit early to see many returning waterfowl. Presqu’ile Bay was still mostly frozen and there was quite a lot of ice close to shore. The ducks that were present were feeding at some distance from shore. In addition, there was a stiff north wind, which made the viewing station overlooking the bay extremely cold. Milder temperatures this week may result in better waterfowl viewing this weekend, although helpful volunteers will not be available to identify the birds. The bonus for visitors on the official waterfowl weekend was a Snowy Owl on the ice in the bay.

Canada Geese can now be seen flying inland to harvested corn fields south of Highway 401 to feed. Fields in the north part of Northumberland still have quite deep snow, but it is melting quickly. It is worth scanning the flocks of feeding Canadas to see if there are any white birds among them. These might be Snow Geese, whose flight path is normally further east in Ontario. On the other hand, they could be Tundra Swans, whose flight path is normally further west through Long Point Bay on Lake Erie. Depending on the winds, either species can appear here during migration. Both are travelling from the mid-Atlantic seaboard in the U.S. to the Arctic to breed.

Among the Canada Geese may also be many dabbling ducks, although they can be difficult to see amongst the larger birds and corn stubble. Most of these will be Mallards, but there may be some American BlackDucks, Northern Pintails, American Wigeons and Wood Ducks.

The Grimsby Hawkwatch is reporting some movement of raptors. Somewhat surprisingly, the largest total for one species to date is Turkey Vulture. Surprising, since Turkey Vultures have no feathers on their head, so might be expected to need warmer weather to survive. Perhaps our highways’ abundant supply of roadkill is all that vultures need. Turkey Vultures could be seen locally all week, especially on windy days.

Northbound raptors enter Ontario along the NiagaraEscarpment and then disperse from here to the rest of the province. Spring migrant hawks tend to travel west to east in Northumberland.

If we ever get warmer temperatures with southerly winds, there will be a flood of backlogged migrants.