Hot weather slows fall migration
Weather always plays an important role during fall migration. As birdwatchers, we anticipate the arrival of fall migrants when cold fronts pass through our region. If there are thunderstorms, often migrant shorebirds will be grounded briefly along the Ottawa River as the inclement weather moves through. On clear, cool nights you can hear the chip notes of nocturnal migrants as they migrate overhead making their way south.
The battle between summer and fall weather conditions will soon be over as warm temperatures give way to the cooler fall days. With the hot and humid weather this week, southbound migration was at a snail’s pace. Hopefully a major change in the weather and a cold front or two will bring in more migrants.
The Ottawa River between Shirleys Bay and Deschênes Rapids continues to attract a variety of migrants as water levels drop, exposing mudflats for shorebirds, ducks, gulls, herons and terns to rest or feed. On Aug. 14, there was a good variety of shorebirds at Shirleys Bay, including Greater Yellowlegs, Lesser Yellowlegs, Semipalmated Sandpipers, Least Sandpipers, and a Semipalmated Plover.
Most shorebirds were in juvenile plumage with only a small percentage of adult birds. Up to 12 Great Egrets were feeding and an immature Bald Eagle was observed soaring over the bay. With the extensive mudflats there were two family groups of Sora Rails feeding out in the open and at least one family group of Virginia Rails. These species are usually secretive, stay hidden in vegetation and are seldom seen.
The Eared Grebe found last week near Pointe Fortune east of Ottawa was still present on Aug. 14.
Common Nighthawks are now on the move south. On Aug. 14, Ray Holland observed two large feeding flocks totalling over 130 birds in the Pakenham area. I’ve also received a couple of sightings from the Carp and Almonte areas of small groups of five to 10 birds observed at dusk.
Mid-August to early September is a good time to be on the lookout for large migrating flocks. Over the past few years large feeding flocks of up to 250 have been observed between Ottawa and Pembroke at dusk as they fly catch high in the sky.
Britannia Conservation Area/ Mud Lake continues to be the hot spot for new migrants. On Aug. 16, both Yellow-bellied Flycatchers and Olive-sided Flycatchers were reported along with a number of warblers, including Bay-breasted Warblers, Cape May Warblers, Canada Warblers and lots of Yellow Warblers.
The heron colony on Conroy Island at Deschênes Rapids had a number of juvenile Blackcrowned Night-Herons. On Aug. 14, I counted 24 juvenile NightHerons as they rested in the shade along the edge of Conroy Island.
Over the past few years, 50-plus juveniles have been counted during mid-August. Black-crowned Night-Herons first bred in the Ottawa-Gatineau district in 2004 and has been a regular breeder at the Conroy Island site at Deschênes Rapids since 2006.
There were still four Great Egrets roosting, too. The exposed rocks at Deschênes Rapids had a nice selection of gulls and terns, including six adult Caspian Terns and five adult Great Black-backed Gulls, along with 250 Doublecrested Cormorants.
The annual Ottawa Field-Naturalists’ Club Seedathon takes place Sunday. It raises funds to supply birdseed to the five public club bird feeders. To raise money, a birding team goes out for a day and tries to identify as many bird species as they can by sight or sound. Those who wish to sponsor can contribute per species found or a flat amount. Please contact Bernie Ladouceur at vbladouceur@rogers.com for information.