Breeding birds court, mate, fascinate

THE WORLD OUTDOORS

There are many compelling aspects of birds. Often it’s their beautiful plumage that draws us in. Birds’ behaviours, however, can be equally interesting.

For birders who revel in observing a particular bird or bird species, spring presents remarkable opportunities beyond simply adding entries to a checklist. A bird watcher might key in on how birds feed or fly, but through spring breeding, courting, mating, and nesting behaviours are also fascinating.

As a rule of thumb, large birds start the breeding cycle early. Smaller, more vulnerable birds wait until there are fewer risks for them to face before nesting.

One of the first species to nest each year is the great horned owl. Londoners again had the opportunity to watch the development of a family of owls at Gibbons Park. After hatching in late winter, three owlets grew at quite a rate as the parents brought a steady supply of squirrels to the nest.

The owlets stepped out of their nest in April and started to stretch and strengthen their wings, legs and feet. They were fledged about 10 day ago but there have still been opportunities to observe these birds since they stay rather close to the nest site.

Cygnets have already hatched as have bald eagle chicks. I had the opportunity to see bald eagles at a nest north of the city this past week. The nests are massive and they are built high up in trees so it’s often difficult to see the young until they have grown.

Canada geese are incubating eggs now. Other species are building nests and mating.

Ospreys often nest on manmade structures. You can watch these birds around the city as they bring in branches and clumps of sod to refurbish last year’s nests. I have had reports of ospreys mating this week.

I watched belted kingfishers in and around their nesting burrow along Medway Creek north of London and have seen several other nesting birds. Watch for them flying purposefully with beaks full of grass or other nesting materials.

There are some species that prefer to nest on built structures. Birds such as American robins, barn swallows, and cliff swallows will nest on buildings, bridges, or other structures.

By all means delight in seeing new birds. I was excited to have seen my first wood thrush, Eastern meadowlark, and house wren this week. I also savoured what will be among my last views of winter birds such as common merganser and dark-eyed junco.

But stop, look, and listen at our breeding birds. They are telling us interesting stories.

• Pied-billed grebe numbers reach a seasonal peak through Middlesex County now. Most water birds either dive or dabble for food. The pied-billed grebe has another trick however. They sometimes simply sink into the water like a submarine by compressing their feathers to get rid of trapped air and reducing their buoyancy.

• I’m always I capture a bird’s vocalization when filming birds but I find the recording of bird sounds challenging. The Cornell Lab of Ornithology recently published on their allaboutbirds.org website some excellent tips about creating these recordings. To read this interesting and useful article search on “record bird sounds with your smartphone.”

• Butterflies, have different seasonal distributions. Butterfly species such as cabbage white, mourning cloak, and red admiral are being seen in good numbers across Southwestern Ontario. Watch for monarchs, viceroys, and Eastern tiger swallowtails in May. We will see great spangled fritillary, silver-spotted skipper, and red-spotted purple butterflies in June.

• Those visiting the Wellington Road entrance point for London’s Westminster Ponds Environmentally Significant Area will see restoration work well under way. Much buckthorn and dead ash has already been mulched and a new accessible trail is now being created. Much of the work will be completed by June. g.paul.nicholson@gmail.com