The Garden Diary 2011
March (part 2)
11 March - A dull but dry day, with the temperature going up from around 4C first thing to 11C in the early afternoon. In contrast, yesterday was largely bright and sunny, although the temperature on got a degree warmer (12C).
The pond has been warming up over the last few days. By yesterday evening it was up to 6.5C and tonight it has reached 7.5C. This has had an effect on the frogs which became much more active yesterday. By last night I was able to count 30 in the bog pond, with a further six in the small pond.
Today the level of activity was obvious whenever I looked out of the window towards the ponds, and in the shallow water there was a centre of attraction for the frogs in the form of the first frogspawn of the year - Spring has come to mybitoftheplanet!
Just one clump was enough to trigger a raised level of 'excitement' amongst the frogs with them visiting the spawn frequently and also dashing to any movement that may signal the presence of a potential mate.
Unfortunately they were also very sensitive to my movements, diving under muddy water as soon as I got too close. I had to remain still for a couple of minutes before this pair dared to visit the spawn.
While it splashed about in the water it was joined (at a safe distance) by a Blue Tit which continued after the Robin left the water.
However, it soon had to give way to one of the Great Tits, and what I think was a second Robin which was in the water for just a few seconds.
The Great Tit nest box continues to be quiet, and while the cameras continue to monitor it I have started connecting up the multiplexer(s) needed for the Swift and House Martin nest cameras. I had intended to go up into our loft today to connect the power supplies but after a bit of a rough night (which involved being asleep by 9pm, only to be wide awake again by 2am, then spending the next couple of hours drinking hot chocolate and browsing the web before getting a few more hours sleep before 8.30am!) I decided try again on the weekend.
12 March - A day that started off bright but which descended into greyness as the afternoon arrived. During the morning the temperature climbed from an initial 7C at 8am to around 13C at noon, but fell back to 9 by the late afternoon.
That variation was reflected in the frog activity seen today. For most of the morning their dashing and splashing could be seen from the house, and croaking could be heard from the veranda. Once the cloud cover was established the water surface soon became more or less still.
To emphasise how quiet the pond had become by tea-time, when I took my
camera down to the pond there were none of the usual splashes of frogs
diving for cover, but just this one showing itself at the surface.
However, look carefully and you can spot a second frog under the water. This one would have escaped my notice if it hadn't been for the use of a polarising filter on the camera lens, used to reduce reflections of the cloud cover.
As suggested yesterday, I headed for the loft this morning to switch on the Swift and House Martin cameras. To my great relief they all seem to be working, and are now linked to a multiplexer, along with the main Great Tit camera.
And a check of the lighting and images after dark. The black & white cameras use infra-red lighting to provide images at night. The external House Martin camera image is more or less lost at night because colour cameras rely on visible light.
In the Great Tit box the light is provided by a very low level of
illumination from a 12v tungsten car interior bulb. This arrangement has
proved successful ever since the early use the webcam without causing
problems for birds that are nesting.
Last year we had both a House Sparrow and Blue Tit use the nests at
I want to avoid any major work on the Martin nests, but at some tome over the next month I will probably use a small vacuum cleaner along with a narrow length of tubing to clear the nests of this accumulation of droppings.
Tonight, the Sparrow is the only occupant in any of the nine boxes.
The state of that nest suggests that there has been very little activity in neither that nor the lower nest during the Winter, but I will be watching it with interest over the weeks to come.
Having said that, a sparrow popped into SW-LE briefly at 4.50pm.
I've made the decision not to clean out the Swift boxes, on the basis that in natural circumstances that would not happen. However, I will be replacing the so far unused straw rings in S-LO and S-RI with smaller versions. Hopefully, when the Swifts return there will be a few more at least looking for nesting sites for 2012.
13 March - It's a grey, wet morning with a temperature of just under 10C at 9am. In fact, it was also raining before I headed for bed last night - a fact that curtailed my inspection of what was a rather noisy pond before I got to do any counting!
The rain didn't last beyond the middle of the morning, but it remained largely grey for the rest of the day.
Yesterday I may have been mistaken in assuming that the Swift boxes are inactive. When I first switched on this morning, at 7.30am, there was a Starling in box SW-Right. I didn't get the chance to grab an image of that visit, but in the hour or so since the other three boxes have all been inspected by Sparrows.
As these images show, in SW-Upper that inspection included shuffling, in fact numerous shuffles, with the box being occupied for over half an hour. For a short time it was occupied by a pair
Could we be in for a repeat of last Spring's nesting attempt?
All four boxes received repeated visits through much of the morning. The Starling visited SW-right a couple of times, and also popped into SW-left just once for a few seconds.
At the moment I'm only set up to record images from one nest box at. This means that is a bit of a 'lucky dip' as to what pictures I will have available each day, unless I happen to be near enough when something interesting takes place in order to switch between cameras.
This evening the Sparrow rooster returned to Martin nest 1 at 5.40pm and before it snuggled into the corner I was able to grab this one image that shows it to be a female.
Yesterday I made the mistake of saying it was a male.
The highlight of the day came when I took my (just turned) three year old grand-daughter Erin out into the garden and stood back as she crept cautiously down the path to get close to the frogs. Even her small form was enough to cause many of them to dive for cover but enough stayed on the surface to bring a big smile to her face. One perched on a stone right in front of where she stopped, much to her delight, and she was happy to just crouch down to watch it closely for a minute or so before it leapt back into the water. And of course she was able to show off her counting skills!
Thanks to her mum and dad she is already used to handling frogs (and any other small wildlife) that turn up in her garden with care, and she also met up with frogspawn and tadpoles here in our garden last year, but now she has reached that magic age of questioning will make things far more interesting. Today as she looked at the frogspawn, which she thought looked like bubbles, she straight away asked what was in them. My short answer today will be developed over the weeks to come. This afternoon I set up a small tank with pond water and some plants (plus snails and other things), and I'll be adding some fresh spawn tomorrow. We shall have some fun!
Down at the pond tonight things are quiet once again. Yes there are some frogs about, and several new clumps of spawn have appeared today, but I have yet to see the 'rugby scrums' of males competing for the prime amplexus grip on a female.
Apart from one small clump just out of frame at the top, this photograph records the total spawn so far. It has reached the stage when it becomes difficult to count individual clumps without the need for close inspection of their relative development.
Temperatures at just before 8pm tonight are a bit of a mixed message. While the water temperature is 8C, the air above the pond is just 2C under mainly starry skies - we are likely to get a touch of frost overnight unless the clouds roll back in.
14 March - A bright, sunny day in store for us after a cold start. There was a sharp frost first thing, enough to completely freeze the water in the bird bath, but the water in the ponds had enough of a heat reserve to prevent any sign of ice on them. Nevertheless, the temperature of the big pond dropped from 8 to 4C.
I'll get back to the pond later, but first some news from the bottom of the garden - the wait is over!
At 8.20am the radio mike picked up the sounds of a bird just outside the nest box, and moments later the face of a Great Tit appeared at the entrance. It spent several minutes looking in and pecking at the timber before finally entering for an inspection that lasted just over a minute.
The image is not very bright at the moment, but I won't turn on the daytime lighting until I feel that the pair is established in the box. However, tonight I will change the glass and remove the straw.
Up on the side of the house there has also been some activity. A Sparrow
has been doing a bit more 'sorting out' in SW-UP, involving moving straw
about and shuffling,
and the Starlings made a single appearance in SW-right at around 7.30am.
This was only a brief visit, and when they left they flew directly to the box that they have spent much of the winter in - one of the boxes I put up for neighbours last year.
As much as I have found the Starlings' nesting fascinating to follow,
later today I may get out my ladder and (as I did last year) block the
entrances to SW-le and SW-ri until near to the arrival time of the Swifts.
If I don't do this then I run the risk of badly disrupting the Swifts'
nesting as the Starlings would defend their territory very aggressively.
Instead, after checking the maximum entrance heights I have reduced them from around 36mm down to 33mm. Swifts actually only need it to be 30mm, so there is still enough of a gap for House Sparrows to enter.
In that picture, notice the narrow slits immediately below the lid. When the boxes were being used by Starlings I found that the level of lighting in the boxes was not good during the daytime. While the IR LEDs worked well during the hours of darkness, in the day the cameras couldn't cope well with the great contrast between the very bright entrance and the shaded nesting area. To overcome this problem, rather than mess about with extra lighting I experimented with raising the lid slightly. It worked (as you can see from the Starling picture above) and since then both Starlings and Swifts have nested with no problem.
In this picture these are marked with arrows. On the inner surface of the doors I have used pieces of translucent milk bottle container to act as diffusers.
Here are 'before (left) and after' CCTV images that show the effect of adding those gaps. The picture is definitely better now, but I must wait to see a bird in there in order to confirm how much the increased contrast will give better images of its plumage.
Lighting is aided greatly by the fact that we have a narrow shared driveway, and my neighbour's south-facing wall, painted in a light colour, acts as a great reflector all through the day.
The sunshine continued as far as the mid-afternoon, and it encouraged the noisiest frog activity for days, although as soon as the clouds rolled in most disappeared once again, and at dusk I see no new clumps of spawn.
The tank being used is a 18cm cube, made to fit in a large ice-cream
container for our trips to Cornwall when not being used for frog spawn!
Click on images to see larger versions