11-APR-2011
Chicks hatch on cue.
When I checked the nest yesterday there was still no chicks in the nest which wasn't a surprise as they were not really expected until 11th or 12th of April. So I was quite hopeful when I visited to check this evening.
Thankfully the water level hadn't risen any further, infact it had brobably gone down an inch or two. I waited for the female to leave the nest before moving down to check the nest. I am really glad to be able to report that 3 of the eggs have hatched and three healthy chicks are in the nest. One egg is either infertile, or "dead-in-shell" or more likely incubation started with the 3rd egg and not the 4th. If this is the case this will contradict everything that I have read previously which seemed to suggest that incubation always commenced when the clutch was complete. If the 4th egg should hatch tomorrow, then this will confirm that incubation started on Sunday, when there was only 3 eggs in the nest. I am looking forward to finding the answer tomorrow. The chicks were pink skinned which was a surprise, I expected them to be dark.
I watched the male already working hard finding food and delivering it to the nest, even if I had not checked for myself, I would have known that there were chicks in the nest just by the male's change in behaviour.
9th April 2012
Before you start reading this entry please be aware that I am a registered member of the BTO's nest recording scheme.
It's now 17 days since the first Dipper egg was laid in the nest at the territory that I have been keeping a close watch on since the beginning of February. This week is a crucial one. It is said that incubation will not begin until the last egg of the clutch is laid and there are 4 eggs in this clutch. It is likely that incubation commenced on the 25th March which coincided with the 4th egg, however as part of my records and individual observations of this pair, I need to confirm that this is the case. There are several possibly variables. Apart from the above there is the possibility that incubation could take 16 days or even less. It is also possible that incubation could have comenced after the laying of 3 or even 2 eggs. Only discovering the date that chicks hatch can this be confirmed. The earliest date that hatching could have ocurred is today. It was important that I checked the nest contents today. I can confirm that there are still four eggs in the nest and as yet no chicks. My method of checking, in accordance with the laid down procedure and advice from the BTO, is to sit unobserved, watching the nest. When the female has departed the nest is the time to make your move. My observations for the last 17 days have shown me that the female, after leaving the nest, has the habit of flying away upstream and is away for 8 minutes. This is ample time to quietly and without fuss, check the contents of the nest, but after first confirming that male is away from the area with the female. To check this nest requires a wet foot as it is situated above water on a vertical moss covered bank.
April 8th 2012
The weather forcast for the next couple of days is for rain and it is possible that I won't get the chance to check on the nest tomorrow, I hope to be able to because it is the start of an important week for the Dippers. I decided to have a quick check of the nest site and the breeding pair late this evening. The male was in front of the nest when I got there, it's always good to see him at the nest, confirming that there isn't a problem. Nothing special to add from this evening except that the male stood in front of the nest for quite a while, he was making that sibillant churring sound here and there, and had he got a response from the female in the form of a churring answer, I'm sure he would have flown up to her but he didn't. Considering that it's now 16 days since the first egg was laid and they are due to hatch within the next day or so, it's a surprise that she didn't invite hime to feed her. It will probably be easy to know when the eggs have started hatching because I am expecting the male to deliver food to the nest, that will be a change in recent behaviour. Just before dusk, the male was still in front of the nest and still making his churring noise. I felt a bit sorry for him, because he hasn't taken part in the incubation. He is detached from what is going on and has kept quite a lonely vigil for the last 16 days. Incubation is said to last 16 or 17 days and also to start on the day of the laying of the final egg of the clutch. This is to ensure that all eggs hatch simultaneously, not all birds use this syncronised incubation. Some species will incubate after the second egg meaning that chicks hatch on different days. The benefit of this is that the older chicks are inclined to get the "lions" share of the food brought to the nest. Only when their is a plentiful supply do all the chicks survive. In Dippers, all the chicks will have an equal chance of survival.
7th April 2012
When I arrived at the nest this morning, I crept in to the hide quietly and I expected to see the male Dipper waiting in front of the nest as normal. I have to admit that it started to frighten me when 15 minutes later I was still Dipperless! Was everything OK, I was just a little bit concerned. I was relieved when I heard the male approaching, fast and low as normal. He landed opposite with his usual noisy fanfare with a beak full of Mayfly. He flew to the nearest boulders just under the nest and called, bobbing incessantly but didn't fly up with the insects. I suspected that the female wasn't in the nest but I was wrong because out she came. She did a bit of dipping and then left upstream followed by the male. There wasn't a lot different to see, she was away for the usual 8 minutes, he returned and sang as normal. Just a few more days to go now before the eggs hatch and the only thing to report of note is the massive increase in insect life. It's also worth mentioning that in the hour that I was watching, the fem ale left to feed twice, the same pattern that I observed the day before yesterday.
April 5th Adult Mayflies on the wing.
I watched the nest yesterday for a couple of hours in the afternoon. It's now 14 days since egg laying began and incubation has thrown up a few interesting facts. To start with, the female, who does all the incubation has now developed the habit of leaving the nest to feed every 30 minutes or so. As I have said before, she is away from the nest for just 8 minutes, literally to the second. The male is not always aware that she has departed and yesterday I watched him arrive with a healthy beak full of adult Mayflies. This is the first time that I have seen the male, or female for that matter, feeding on adult Mayfly and my guess would be that the entire breeding cycle has been timed perfectly so that when there are chicks in the nest there is going to be a proliferation of Mayfly. He called to the female from a boulder close to the nest but didn't get any response because she was away feeding. He continued calling her but didn't fly up to her with the flies. I made the assumption that had she been in the nest she would have responded and he would have delivered the insects. I am certain that this is the case but I haven't heard her calling from the nest. before and it was interesting to realise that he was waiting for a response from her. Eventually after flying from boulder to boulder in front of the nest, he decided to eat the food himself but not before he had spent at least 5 minutes calling her. To think that the arrival of chicks in the nest has been timed to coincide with the Mayfly hatch is a stunning fact. Quite how that has been judged is a mysterious wonder to me.
03-APR-2011
3rd April and one month on.
In the Photo, the male keeps sentry duty in front of the nest.
It is exactly a month since I first discovered the nest site on March 3rd. The female is still sitting tight and incubation is in progress as hoped for. The male, who his taking no part whatsoever in incubation, spends the majority of his time sitting on a midstream boulder near to the nest. He flies, mostly upstream, to a favoured feeding area. He can be away from the nest area for as long as 20 minutes. On his return, which is always a noisy and excitable affair, he will invariably land back on one of his favourite spots and sing loudly for a minute or so. This singing fulfils two functions, firstly it is a signal to the sitting female that he has arrived and secondly he is singing to proclaim to any other Dippers that this is his territory. Yesterday when he arrived back, the female chose to leave the nest and immediately flew upstream, presumably to feed. What was different was that the male didn't follow her which he has done on most other occasions. He just remained sitting quietly, still on his boulder. As the minutes ticked by, again it was just 8 minutes to the second when she arrived back, splashing in to the water in front of the nest and climbing out on to a boulder. She dipped a few times, and then flew straight back to the nest, acrobatically and without pausing. Going in to the nest she always flies vertically from beneath. It is hard to report anything new during this period, but interestingly, the male seems to have stopped flying up to the nest to feed her now. He did this regularly when incubation first commenced but now she seems to go off to find food for herself.
02-APR-2011
2nd April the female wets a beech leaf from the nest.
Everything is safe and well at the Dippers nest today. The male visited the nest after catching some prey and the female is still leaving the nest to feed more regularly than you would imagine, at least once an hour. At one time she emerged from the nest with a beech leaf, dunked it in to the water and took it back to the nest. Natures way of ensuring the correct level of humidy in the nest no doubt. I am assuming that incubation started last Sunday or Monday it's day 7 or 8 of incubation now.
31st March
My observations today highlighted some slight changes in behaviour from both birds. The male spent the majority of the time that I was watching, perched on a boulder in midstream. When I had last been at the nest site two days ago, the male had been quite keen to visit the nest often, either to feed or to strengthen the pair bond, but today this didn't happen. He seemed content to wait for his mate to emerge and then accompany her when she went off to feed, which she did at least once every hour. On another occasion, first a Goosander and then a Heron arrived in front of the nest and this caused a degree of panic from both birds and with the arrival of the Heron, the female left the nest and both birds rapidly flew upstream quickly and away from the scene. There was also some disturbance from walkers and a barking dog in the adjacent wood. This certainly stressed the male who 'escaped" upstream by diving in to the water and swimming underwater upstream. I have read that Dippers sometimes escape predators by diving underwater and I am sure that this was an example of this and the first time that I have seen this behaviour. It wasn't long before the female returned to the nest as normal. Incubation is progressing nicely on the 6th day of incubation.
29-MAR-2011
29th March
I observed a couple of interesting pieces of behaviour this morning. The female is very quiet in everything she does and when she is the Dipper that I can see in front of me, I am quite certain that it is her by her quiet demeanour. This morning for example I saw her slip out of the nest and then fly up river. After a few minutes a bird returned and I knew immediately it was the male, he flew in calling very loudly as normal and then immediately started singing to proclaim his territory. A minute or two later she arrived back and very quietly started to look for prey, underwater of course. The male sat waiting for her, she flew to him and then they both flew off back up river together. I checked the time that she had been off her eggs, yesterday it was 8 minutes. It was around 8 minutes again when she flew back and very quietly slipped back in to the nest. I need to confirm this with many more observations over the next week or so, but it appears that the birds have an "internal clock" that instinctively dictates their behaviour to a strict timetable. Hence the male visits the female in the nest every 30 or 35 minutes. This morning I watched him fly up to her and make quite a noisy fuss as he communicated with her, hanging on to the nest with the majority of his body mass inside. Previously I had thought he was feeding her but I am 100% certain that he did not carry anything to the nest on this occasion. It's obviously just a way of confirming and strengthening the pair bond.
28-MAR-2011
28th March, a clutch of four eggs and incubation progresses.
The photo shows a close up of the males wing showing some wear and tear. The morning was spent trying to get better photographs of the Dippers flying up in to the nest. I am running out of ideas as to how I can improve now, it just isn't bright enough to get the shot that I am after. In the end, having spent most of the morning trying, I pretty much had to accept defeat and be grateful for what I am seeing and if I manage a decent photo, in-flight, then that's a bonus I suppose. I am learning a lot about breeding Dippers as you would expect and I hope that you (the reader) is learning something as well. It's been interesting to see the behaviour of both birds at this stage, the incubation. The male seems to be almost at a "lose end", sitting around waiting for something to happen, from time to time he goes off to find some food for himself and the female. When he returns to the nest site, I can hear him from quite a distance away, he always calls loudly (and musically) before he lands on one of the nearby boulders. I take this as a signal to the sitting female that he is nearby. After landing he will sing for a minute or two before flying up to the nest, only half entering, and hanging on as he gives the female his offering. Then out he will come after as long as it takes for her to take the food, flopping down in to the water and swimming to the nearby boulder. When he is in the nest he always makes that churring sibilant noise that I heard when they were first building and when they swopped over building duties. This is undoubtedly to get the female's attention so that she is ready to take food from him. It again seems that the male will bring food twice in around 70 minutes, almost like clockwork. However on two occasions as I watched this morning, the female left the nest, presumably to drink, find her own food and defecate. On the first occasion the male was unaware. She was away from the nest for 8 minutes. The second time the male accompanied her and they both flew upstream to feed. Interestingly both birds are prepared to fly several hundred yards away from the nest to feed rather than around the nest area although there does not appear to be a pattern to this feeding behaviour as the male is also quite content to feed in front of the nest. On the second occasion that she vacated the nest I quickly took the opportunity to check the size of the clutch. This is important to know for my BTO nest record card. As refered to previously I am collecting important data about dates of building, egg laying clutch size and the viabilty of the nest as part of the BTO's nest recording scheme, hence my reason for checking the nest. There will be no need for me to check the nest again until around the hatching date when the date of hatching will be recorded. Dippers are said to lay a clutch of four or five eggs, ours have four!
27-MAR-2011
27th March
Now that the female has started to incubate her clutch of eggs which takes 17 days, there is going to
a lengthy period when not much happening. The pattern of behaviour observed this morning is likely to be repeated daily and it's going to be a quiet period in the breeding cycle. This morning when I arrived I couldn't see any Dippers around the nest, I assumed that the female was in the nest and the male away finding food. AsI lay under cover watching a bird arrived, splashing in to the water and then swimming up to the rocks beneath the nest before flying up. It was silent as it entered the nest and I had the feeling that this was the female, this proved to be correct because the noisy male arrived a few minutes later, singing his call as he flew in and then breaking in to sing before he visited the nest, perhaps with food but I couldn't be sure. I have established that there is approximately 30 minutes between male feeding visits to the nest so it can get a little tedious as you wait with nothing going on. Sometimes the male sits nearby, singing away and preening before he flies up or down stream to find food. Twice this morning the female left the nest to find her own food, whether this means that she has not started to incubate properly yet I am not certain but as "sitting" progresses I will be able to see if this is normal behaviour.
26-MAR-2011
26th March Four eggs now.
I travelled to the River at around noon. As expected and hoped for, there was a Dipper by the nest when I got there. I slid under the cover without the bird which was the male, again as I expected, being none the wiser. I sat and watched him for a few minutes, he flew up to the nest carrying an insect. I am pretty sure that he was feeding the sitting female who by now should have been sitting on a nice clutch of 4 eggs. He was noisy as he delivered his morsel to her. Exactly 30 minutes later he was back to bring her more food which he did in the same noisy fashion. Then around 30 minutes later he flew up to her again and I could clearly see that he was carrying food still as he emerged again, this time he flew back down still with the insect. This intrigued me at first but then I saw the female feeding in the shallows just upstream. He obviously thought she was in the nest the same as I! After just a short while she went up in to the nest and he displayed to her as she went in leaving him alone again on the rock. Later on in the afternoon after I had watched the Wagtails further upstream I returned to watch again and saw her emerge again, both birds flew off upstream and I guessed that they would be away for at least a few minutes giving me the opportunity to check the nest and confirm that yes, she has got 4 eggs now. I quickly went back "under cover" and waited to see her return to the nest which she did, everything is going just perfectly.