A Lewis woodpecker.                                Photo courtesy of Paul Graham

A Lewis woodpecker. Photo courtesy of Paul Graham

Nature Wise: The missing birds of summer

The sure signs of summer in the South Okanagan was the appearance of certain birds

Since moving to Kaleden in 2003, one of the sure signs that summer was near was the appearance of common nighthawks swooping about over the lake and hillside below our house as they gathered the insects that make up their dinner.

The black and white pattern on nighthawks’ wings is so distinctive that there is no mistaking them with other birds.

I had seen nighthawks prior to moving to Kaleden, but it was really spectacular to watch them from our deck as they swooped about, often so close I felt I could reach out and grab them. They never appeared before early June and by the end of August they were gone. They were generally in fairly large flocks (20 to 40 birds) and while they didn’t show up every day, you could count on seeing them at least a few times a week.

So far this summer (as of July 31), I have seen exactly none from my deck! While by itself this would be alarming, what is more significant is that the number of birds we have been seeing (and their frequency) has been diminishing over the past five or six years. From 2003 until about 2011, the nighthawks were common and frequent over the Kaleden hillsides. Since 2011 the number of birds seen has been gradually diminishing and this year zero. Last month I did see a dead nighthawk on Highway 97 in Penticton so there are some around.

Contrast that with a different bird that also appears to be missing this summer — Lewis’ woodpecker. This beautiful woodpecker usually migrates back to the Okanagan about mid-May and leaves for the south in early September. We have generally seen these birds from our deck starting in mid-July after the young have left the nest and they fly about the neighbourhood more. While never close in numbers to the common nighthawk, we saw them often enough that we could assume all was reasonably well in their world. Last summer, we saw more than ever; one day I can remember seeing six at one time flitting about in the trees near our place. This summer, none at all. Now I know there are Lewis’ woodpeckers in the Okanagan Valley this summer as I have seen reports of some but they certainly seem to be missing from my little part of the world.

Yet another “missing” bird this summer is the hummingbirds. In actual fact they are not really missing, but I have heard from a number of people that there does not seem to be as many as usual.

This type of evidence (casual observers reporting something) is generally called anecdotal evidence — it consists of small personal accounts, generally not recorded in a scientific manner. But anecdotal evidence can be significant if it is widespread and corroborated by numerous people or other evidence. The fact that I haven’t seen any common nighthawks along the banks in Kaleden is one thing but if most other birders in Kaleden and adjoining areas such as Penticton report that they also have not seen any nighthawks that becomes significant. When we consider that bird scientists in Canada estimate that the population of nighthawks is declining at a rate of more than 6 per cent per year (between 1995 and 2005 the population decreased by nearly 50 per cent), that suggests that my observations may be factually important.

As to the lack of hummingbirds this summer, the hummingbird banding stations at Kaleden and Princeton have captured far fewer birds this season than last so there is some independent scientific evidence to support people’s general feeling that hummingbirds are less common this summer.

The population trend for nighthawks is disturbing. The observations about Lewis’s woodpeckers and hummingbirds may be little blips that mean nothing. Let’s hope so.

The South Okanagan Naturalists’ Club’s monthly meetings will resume again on a regular basis on Sept. 28. In the meantime we have weekly birding trips (Thursday) and occasional field trips. If you would like to come along and learn about our club you can check out the activities by going to www.southokanagannature.com.

Bob Handfield is president of the South Okanagan Naturalists’ Club but the views expressed here are his own and not necessarily those of the club.