Female-duck mystery

 

It is a mystery to me why female ducks sit atop pilings in the early morning at the beginning of the breeding season. They don’t do this at other times. I have been watching female mallards do this for a number of weeks this year. But, the behaviour is not confined to mallards. Other years I have seen mergansers and goldeneyes also perch atop pilings, all of them females. 

These females do not seem to be seeking a mate. Most have already paired off. Indeed, the mate is often on the water below, and after a while on the piling, she flies down and joins him. 

Has this behaviour evolved? There have only been pilings on this lake for less than a century and a half. If, as is likely, the behaviour is ancient, what previous structure has been supplanted by the convenience of wooden pilings? (Ducks cannot perch on the conically topped metal pilings.)

Who knows the purpose of this behaviour?

Now is the brief season of female mallards perching atop pilings.

 

Posted in birds, commentary | 6 Comments

Deer, ducks, mud, & leaps

 

Two white-tailed deer stopped by in the predawn light and entranced me with a display of leaping.

First, one deer needed to greet the new day with some matutinal micturition. 

They then began to leap. At first, I thought maybe they were just frolicking. Apparently not.

Possibly they were harassing the mallards. No, the ducks were of scant interest.

The leaps carried on. When I looked at the pictures, I realized they were reacting to sinking into the mud revealed at low water. A deer would get stuck in the mud, panic, and leap. 

“OK, I think the time has come for us to move along the shore.”

 

Posted in mammals | 4 Comments

Incipient grouse courting

 

March and April is a time for the Ruffed Grouse to court and mate. Three years ago this month, I managed a shot of a male in full courting display (right) in front of an adjacent female. He had his ruff expanded and his tail upright and spread. 

Now, after a winter in which no grouse displayed its ruff, there is a sign of interest. Yesterday’s ruffed grouse showed a hint of a ruff to its nearby partner and a spread, but not raised, tail. 

Things may get interesting as the month wears on.

Yesterday’s Ruffed Grouse looks as if he has courting on his mind.

 

Posted in _uncategorized | 4 Comments

Hoodie rarity

 

We have Hooded Mergansers year round. And although this water bird is not as common as the mallard, there are ample opportunities to see them. Yet, only once before have I seen one stand on a solid surface: swim or fly, yes; stand, no. 

The issue is that unlike the mallard, which is a dabbling duck, the hoodie is a diver. So, its legs are set far back on its body for underwater propulsion and this makes it clumsy on land.

Mallards like to hang out on the ramp of a dock, because dogs can only approach from one direction and the birds have time to escape. The comforting presence of a mallard couple has clearly served as a lure for the Hooded Merganser couple.

A Hooded Merganser couple stand together.

 

Posted in birds | 8 Comments

Red-winged Blackbird

 

The arrival of Red-winged Blackbirds is a sign of pending spring; They have now been observed in Nelson over the last week. Twice I have tried to get shots of them, but they tended to hide in the brush. The male’s spectacularly bubbly song reveals them, but pictures amongst the brush proved difficult. Today was no different — except for one spectacular flight in my direction. 

When flying off some brush, a Red-winged Blackbird happened to fly towards me.

 

Posted in birds | 14 Comments

Trumpeters

 

For the past few days, there have been seven Trumpeter Swans visiting the shallows to the south and west of Kokanee Creek Park. I visited them early this morning.

On their spring migration north, both swan species often stop by Kootenay Lake to feed. It works out well for them as the water level is low and dropping, which enables them to use their long necks to gain access to the aquatic plants in the shallows.

One of the curiosities often seen where swans are feeding are other ducks. This swan is accompanied by a wigeon. The attraction for the wigeon is the material that the swan stirs up as it feeds. Plant material rises to the surface and others with shorter necks gain access to it.

An adjacent family of five Trumpeters has attracted other feeders: Canada geese, Mallards, and Buffleheads.

The family of Trumpeter Swans is made up of two whitish adults and three (equally large) greyish chicks. That the chicks are still greyish is telling. Had these been Tundra Swans, the chicks would have already turned white by this time of year.

This seems to be a couple, but with no chicks.

I have saved the best two images for the last. Each was taken by my daughter, Cynthia Fraser. The first shows the spread wings of one of the three juveniles.

The second shows the spread wings of an adult.

 

Posted in birds | 4 Comments

Common Goldeneye

 

 

Posted in birds | 8 Comments

White-eyelid mystery

 

Dipper – the eyelid flashes white when it blinks! This is so different from any other bird that it begs for an explanation.
        David Sybley

A dipper has both a dark plumage and dark eyes. Why would it have evolved a white (feathered) eyelid? David Sybley is an authoritative author on birds who knows the literature, and yet he is unable to offer an explanation. Further, up until this morning, I would have accepted his aside that the dipper’s white eyelid was different from any other (dark) bird. 

However this morning, I saw another bird with a dark head and dark eyes that sported a white eyelid. That second bird was a Black-billed Magpie. Both the dipper and the magpie are somewhat uncommon locally, yet, if you know where to look, they can be found.

When watching a dipper, I often see it flash its white eyelid. Until this morning, I had neither seen, nor suspected, that a magpie could do so also. The sight was so unexpected that I sought confirmation. I found no images of the magpie’s white eyelid on the web, but on the Cornell website, I read about the Black-billed Magpie:

In groups, males establish dominance … flashing their white eyelids.

Now, the magpie I saw was on its own, and so was not seeking dominance. However, the text did acknowledge the magpie’s white eyelid.

So, for what purpose has the white eyelid evolved? The mystery deepens.

A dipper blinks and displays its white feathered eyelid.

This morning’s shot of a magpie displaying its white eyelid.

 

Posted in birds | 8 Comments

Dipper under ice

 

A dipper sometimes forages under ice. 

I believe I know when and why it does so.

The odd thing about this, is that I have often watched a dipper stand on the border ice along a creek, dive into the open waters in the middle, retrieve something, and bring it back to the ice to eat. But, I had never seen one dive into the water and then turn to forage under the ice it had been standing upon. Why would a dipper do this? 

The insight for me started last November when Liv Grant wrote me about dippers in connection with a nature film, “it is quite surprising to see a bird which is not a penguin swimming under ice!” I responded that I had never seen a dipper do this. Then four days ago, I posted about a Common Goldeneye foraging under ice and mentioned the problem with dippers. Two observers, Derek Kite and Bob Stubbs, then wrote me separately to say they had seen a dipper forage under ice. Superb. But, what occasioned the difference between the dipper’s behaviour during their observations and my own earlier ones?

We have now had a succession of days with temperatures of between -15 °C and -10 °C. Local creeks are icy, so yesterday, I went dipper watching. This time, the dipper was seen repeatedly foraging under border ice and I realized when and why they do so. 

First, there is a discussion of the dipper’s behaviour, and then an explanation of it.

A dipper stands on border ice and is about to swallow an aquatic arthropod that it had retrieved from the bottom of the creek.

The dipper stands on the edge of the border ice about to dive.

It would then dive in, but promptly turn and swim under the border ice it had been on.

Finding something under the ice, the dipper brings it to the surface and eats it. It looks rather like a caddisfly larva.

The dipper did this over and over (for as long as I was willing to watch it). Here it can be seen swimming under some really thin ice. Once I saw it travel at least two metres under the ice. It almost always found something worth retrieving and eating.

The dipper doesn’t usually forage under ice. The clue to when it does so is that there has been a succession of days with temperatures below about -10 °C, which festoons the creek with ice. Yet, this doesn’t answer the question of why it forages under ice only sometimes when there is ice. The answer to why lies with the two forms of ice found along a turbulent mountain stream. Border ice, which lies atop the water, forms along the gently flowing creek sides. Anchor ice, which lies on the base of the creek, forms in the turbulent central channel. (See a discussion of how these form.) The dipper acquires most of its eatables along the base of the creek, and the central portion of this is now covered by anchor ice. However, under the border ice, the creek’s base is clear so the hunting is good. The dipper now forages where it can find food, that is, under the border ice. In this earlier picture, the border ice is on the lower left and upper right, while the anchor ice is the yellowish material in the centre.

 

Posted in birds, commentary, weather | 4 Comments

Foraging under ice

 

Last November, I received an enquiry about dippers from the production crew of a nature film:

…it is quite surprising to see a bird which is not a penguin swimming under ice! Do you think that there are any locations where dippers frequently swim under ice?

The enquiry came about because of an essay I had written about dippers and ice. I responded with information about our local dippers, but noted:

I have never seen a dipper swim under border ice. Of course, they might have done so, but, unlike penguins (which I have watched in Antartica) this does not seem to be a behavioural characteristic of dippers. Predicating a filming mission upon dippers swimming below ice does seem to be a bit of a stretch. 

And that was that.

Yesterday, I was watching a male Common Goldeneye foraging in a bay. As does the dipper (which is a songbird, not a duck), goldeneyes hunt underwater where they capture and eat, among other things, aquatic arthropods. While this male did forage in the open water of the bay, it repeatedly swam under the border ice, sometimes returning with a comestible. 

I have no idea what the goldeneye found so appealing under the ice. (Maybe it was influenced by a just-watched nature film about penguins.)

The male Common Goldeneye heads across the open water of the bay and towards the border ice.

Upon reaching the ice, the duck dived under it.

Surfacing again at the ice’s edge with something in its bill, the goldeneye promptly swallowed it. The duck then foraged under the ice a few times more.

 

Posted in birds | 4 Comments