A Visit to Bronte Harbour, Oakville, ON

25 July 2019

     For almost as long as I have known Miriam, we have been making excursions along the north shore of Lake Ontario; in fact a few special memories were created on such outings. So, it was with great delight that we embarked on another adventure together.

     Bronte Harbour is a picturesque little cove, especially appealing in the summer when many craft of various sizes, degrees of opulence and affordability, are berthed at the docks.

     Canada in general is not a flag-waving nation (thankfully), so it is both striking and unusual to see so many flags fluttering in the breeze. 

     For many years Bronte Harbour was home to a thriving colony of American Cliff Swallows (Petrochelidon pyrrhonota) and many nests remain.

     Unfortunately, these nests have been taken over by aggressive House Sparrows (Passer domesticus), an alien species, and not a single nest is any longer occupied by Cliff Swallows. 

     Even where barriers had been installed to prevent the Cliff Swallows from nesting, and raining their droppings on pedestrians below, wily House Sparrows have found a way to beat it.

     It is entirely due to the deliberate actions of humans that this invasive species has become so well established throughout North America, but it has become a serious problem for many native species, especially cavity nesters.

     A pair of American Crows (Corvus brachyrynchos) had obviously had a successful breeding season, and dedicated parents were still being pestered by young birds fully capable of getting their own food, but always on the lookout for a free meal if it was to be had. The begging calls of the fledglings were constant.

     In recent years, chairs (known locally as Muskoka chairs) have become available at various dockside points for people to sit on and enjoy the sun. The chairs are sponsored by local businesses and organizations and add a lovely splash of colour to the environs. 

     I can vouch that it is pleasant indeed to sit on the dock, with the water lapping gently against the seawall, sipping a cold drink, or simply watching the world go by.

          Our principal goal for the day was to see the sizable colony of both Caspian Tern (Hydroprogne caspia) and Common Tern (Sterna hirundo), and we were not disappointed. 

     Caspian Tern is the world's largest tern and in the picture below you can see how it dwarfs the Common Tern off to the left on the breakwater.

     The task of catching fish to feed hungry young is a serious business.

     We were entertained for a half hour or more by these aerial acrobats, and more than a few rested on the breakwater between bouts of fishing. As you can see a few Ring-billed Gulls (Larus delawarensis) were happy to share the space with them. 

     We have become accustomed to seeing large numbers of Double-crested Cormorants (Phalacrocorax auritus) at Bronte, sometimes numbering in the thousands, but today we saw but a couple of flocks far out on the lake, perhaps  forty or fifty birds, and a lone individual perched on the spar of a boat.

    I suspect that this has something to do with the senseless, illegitimate and heartless cull of this species. Someone should start to cull a few of us.
     The breeding success achieved by Red-necked Grebes (Podiceps grisegena) over several years has been quite remarkable. The past couple of years, however, have been equally remarkable for their lack of results and it appears that once again there is complete failure. A bird was sitting on one nest, attended by her partner, but there appeared to be none of the excited interaction that normally is manifest in a breeding pair. There was no exchange at the nest so we were unable to ascertain whether there were eggs. Sadly, we saw no young of the year at all.

     It was quite a different story with Canada Geese (Branta canadensis) where many young are now almost indistinguishable from their parents.

    Several Mallards (Anas platyrynchos) were basking lazily at the water's edge. No doubt they too enjoy a tranquil, warm summer's day.

     I suspect that these birds are males who have moulted their feathers and are in the condition known as eclipse plumage and are now acquiring their new plumage.
     See Kortright (1943) - In the early summer, as soon as the females are well established in their incubation duties, the males of most of the ducks desert them, gather into flocks by themselves, and proceed to moult their bright winter plumage.
     During this moult, the brilliant plumage of the males is gradually replaced by a sombre, inconspicuous dress, which in most cases is almost identical with that of the adult female. This plumage is known as the eclipse plumage.
     The moult which results in the eclipse plumage is known as the "post-nuptial"or "eclipse" moult. It consists of a complete moult, of the body, tail and wing feathers.
      After we left the harbour we went to a little restaurant where we had eaten a couple of times in the past, and always enjoyed it. Lunch was as good in the eating as it had been in our memory!
      We have to be sure to do this again before summer is done with us for another year.