Monday, 3 September 2012

More on the Red-necks

Red-necked Grebe Adult
Red-necked Grebe illustration by Caroline.
Today I checked up on the grebes again. They were far out in the harbour with their young, barely close enough to identify with the naked eye. I knew something was up because their nest is right by the shore (still with two eggs inside), and the Red-necked Grebes never stray far from there.

Looking around I spotted a family of minks, wading in the shallows, trying to swim to the eggs inside the nest! I immediately realized that these carnivorous animals are predators to the nestlings, still incapable of flight, and the rest of the eggs.

The remaining eggs in the nest, however, are long dead. The parents have stopped incubating them since a few days after the first chicks hatched. I believe that the task of raising the young they already have is difficult and time consuming, therefore they would not have the time to keep sitting on the nest, keeping a watchful eye out on nest robbers, and nurturing their babies.

Another predator (or rather simply a bother) I observed was the Ring-billed Gull. A few days ago, one actually tried to steal the fish one grebe had in its bill, the grebe meaning to feed it to a nestling! Noticing the gull flying above it, the Red-necked Grebe just dove underneath the surface of the water without panicking.

So you see, these birds have many predators to watch out for, and that their awareness really is the key to their survival.

Friday, 24 August 2012

Nesting Red-necked Grebes

Today I visited Colonel Smith Samuel Park in Toronto, Canada to check up on some Red-necked Grebes I have been observing this summer. There I saw the breeding pair I always watch in the harbour. This year they arrived late, but still managed to have two clutches. They laid four eggs late July, and the eggs just finished hatching. They may very soon migrate for the winter.

Breeding Red-necked Grebes in Colonel Smith Samuel Park, Toronto
Red-necked Grebe feeding nestling.

The parents were carrying their nestlings on their back (usual grebe behaviour) in between the wings to keep them warm. A few days ago, when only one chick hatched, that nestling would sit on the back of the incubating parent, while the other adult grebe would go find small fish to feed to the nestling. The roles of the parents often switched so that the one fishing for food could have the chance to rest.

I am very curious as to why they are having a clutch so late. They are actually supposed to leave for the Atlantic coast from around late August to October, and although this is not considered to be a long migration, what are the grebes going to do with their nestlings that can only fly from 50-70 days after hatching? Of course, some grebes in southern Ontario choose not to migrate, however winter here is a hardship.

I will keep posted on this family of grebes, to see whether they have chosen to stay, or try to squeeze in the flight before winter. Many other grebes in the harbour have already left.