In the burrow after hatching

Observing the inside of a kingfisher nest in real time via the web cam set up by the Nature Channel in Holland offers a unique glimpse into the world of kingfishers. Here is a selection of stills from inside the burrow.

 

Facts and figures

In addition to the live camera feed, the Nature Channel website in Holland site has a clubhouse where volunteers monitor the kingfisher nest ( and other nest cams) 24 hours a day. The volunteers keep a record of how many times the chicks are fed each day and by which of the adults (fortunately the infra-red camera makes it easy to spot the lighter coloured lower part of the beak on the female).

Now that the chicks have fledged I have some statistics to share:

7 eggs were laid, 6 hatched after 1 egg was accidentally knocked out of the nest by parent.

24 days + 20 hours after the first chick hatched at 11:57 April 12, the 6th chick left the nest at 08:11 May 7.

During the first week the parents spent a large amount of time brooding the chicks, the female more than the male, who took on a larger percentage of the feeding at this time.

By day ten the adults were spending much less time brooding the chicks and the feed rate climbed significantly, the female bringing in significantly more fish than the male at this time.

The female continued to brood overnight in the nest with the chicks for eleven nights after the eggs hatched.

From day 10 to day 15 the highest feed rates were recorded, with 3 days of over 100 fish being fed.

By the time the chicks left the nest both parents had fed the chicks a similar number of fish, the male 577 (36%) and the female 594 (37%) (assuming that the 422 (26%) of feeds the counters were unable to attribute were evenly spread). In total 1593 fish were fed to the chicks.

The daily feed graphs showed that feeding commenced each day within a few minutes of sunrise, and finished in the hour before sunset.

Throughout the feeding period, the individual parents fed at irregular intervals, sometimes making several visits to feed within a space of a few minutes, while at other times they were absent for an hour or more. Despite this erratic behaviour, the cumulative efforts of both parents tended to even out during the course of a day, with the graphs showing a steady supply of fish being presented every day.

This graph shows a distinctive bell curve as the feed rate built to a peak and then tailed off towards the date when the young fledged.

This clutch of youngsters all left within a period of around an hour, the first chick exiting shortly after sunrise 6:19 local time (5:19 BST). Records from previous clutches at this nest site have shown that each clutch has left at a similar time, shortly after sunrise.

overall-feeding

This graph depicts the breakdown of the 1593 fish fed. Blue shows the male count, red the female and green shows fish fed where it was not possible to identify the adults gender. During the final few days the size and voracity of the chicks, taking fish at the nest entrance, made it increasingly difficult to identify which parent was feeding.

 

The graphs below show the feed count and feed times for each day (click thumbnail images to view graphs).

 

Kingfishers – inside the nest burrow

nestcam2The kingfishers that I have been observing nest in a natural burrow in a fairly fragile bank, so it’s pretty much impossible to know what’s going on inside the nest chamber, however there are now a couple of places online where you can not only see clips of behaviour from inside a nest burrow, you can actually observe the entire process live!

The Nature Channel  – (Holland)

This camera site is based in Holland. Follow this link and select the BroedwandCam for an external view of the nest bank or the IJsvogelnest for an interior view of the nest. I’ve been watching the resident pair for a couple of hours and it’s fascinating. You may find it tricky getting the streams to work, but stick with it as it’s well worth a bit of tinkering, and  if you’re using a Windows PC and Microsoft Internet Explorer you should find it easier. As I type this, the male seems to be uncertain what to do with the eggs, he turns up to relieve the female who seems to be getting brooding underway, but he just pops into the nest and comes straight out again, leaving the female to do most of the brooding, he doesn’t seem to know what to make of the eggs, hopefully he’ll get the hang of it.

Winnall Moor

This live streaming camera was set up by the Hampshire Wildlife Trust at their artificial nest site at Winnall Moor.

Here is a link to the live stream, although I’m not sure if it is running this year, as it seems to be off air as I’m writing this. However, here is a link to their youtube site, where some fantastic clips are available, depicting key moments in the incubation cycle from last year.

I highly recommend having a look!

 

Shugborough’s Kingfishers

This is a 15 minute film that I have made using the footage that I gathered during the 2012 breeding season. It follows the adults from pair bonding through to the end of a dramatic and incident packed breeding season. The film is in HD and can be viewed full screen if required.

Hatched!

On arrival at the nest site on Sunday I noticed something in the nest tunnel. It was a shell fragment, a sure sign that the eggs are now chicks! This event marks the beginning of a busy period for the parents as they’ll need to bring in excess of 1000 fish to the burrow over the next 3 weeks, each of which represents a separate fishing trip!

There has been no sign of mink in the vicinity for several weeks now, but I’ll continue to monitor the area and keep my fingers crossed that the weather and local predators leave the Kingfishers in peace this year!

Progression

The Kingfishers have completed the first clutch of eggs and as of Saturday 27th April they are incubating. The female will have laid 5-6 eggs over the previous week at a rate of about 1 a day. She’s been spending most of her time in proximity to the nest site where she has been making frequent visits to the nest burrow. Throughout this period the male has been bringing fish to pass to the female and they have been mating regularly to ensure each new egg is inseminated.

The transition to incubation sees both birds taking turns incubating the eggs. They can changeover at intervals of anything from 20 minutes to an hour and a half. The instinct to brood must be strong as at this early stage their is a visible urgency in the birds desire to return to the burrow. The female actually evicted the male after 45 minutes while I watched today.

There has been no further sign of the mink and I’m hoping that it stays that way. This is a critical and vulnerable time for the Kingfishers, as they become tied to the burrow for 6 weeks, where they are entirely dependent on the limited security that it provides.

Fish of the day

Today marks another important landmark within the breeding cycle. For the first time I’ve seen the female taking a fish into the nest burrow and this means that there are now live young in the nest.

The activity was far less predictable than it has been during the brooding phase. The adults are still leaving the nest site to hunt, but are returning sooner; at one point both adults were inside the burrow for the best part of a minute. It must take them a bit of getting used to, having live young, where the day before they just had 5 or 6 eggs to worry about. With the high attrition rate and short lifespans of most kingfishers, this may well be the first time this pair have bred, so everything depends on their instincts kicking in and triggering the right behaviour patterns at each stage of the breeding cycle. As an onlooker I’m continually fretting about whether the female has been away for too long, or whether the male is staying put long enough, but at the end of the day it’s out of my hands, so all I can do is sit quietly in my hide and watch as events unfold.

The female enters the burrow with a fish

If all goes well, the current phase, during which the adults will have to continually feed the young in the nest burrow, should last about 25 days (although it can be up to 35 days if food supplies are poor).

So the target for fledging is mid May, however, in my experience this next phase is the most precarious. Now the young are in the nest, their calling for food may attract the attention of predators more readily, and it was during this phase last year that the burrow 3ft to the right of this years nest was dug out by mink. I’ve placed a protective mesh above the nest burrow this year, but I’m still concerned.

For now, all seems to be going smoothly. I’ll be keeping a close eye on the burrow over the next few weeks and should also hopefully be able to post some more photos and video footage.

Still Brooding

I did a long stint at the nest site today timing the birds brooding sessions. The female is still staying away from the nest for longer than the male, with the female appearing to average about 2 hours, while the male seems to return after about an hour and a quarter. Although she does shorter sessions, the female does seem to be more settled while brooding. The male will often leave the nest briefly during his brooding stint and catch a fish before returning to the nest, while so far I’ve never seen the female leave the nest before being relieved.

During one of the handovers the male seemed to get spooked just after arriving at the site and calling to the female. He flew off upstream, and the female exited the nest a few seconds later and left to hunt. Throughout the following 2 hours the male returned to the nest but wouldn’t settle in the burrow. Despite entering the nest several times he immediately came out and hovered near the nest bank calling. It seemed to me that whatever disrupted the changeover had completely thrown him, and without seeing the female exiting the burrow he seemed unwilling to enter it. Eventually the female returned, entered the burrow and settled immediately, while the male left the site without having done any brooding. I stayed to watch the next changeover and this time everything went smoothly with the male entering the burrow immediately and settling, after the female had exited it.

Hopefully, this little blip won’t have any ill effects on the young which should be ready to emerge from the eggs within the next few days.

Brooding Kingfishers and an elusive mink

Are you coming out or what?

Since my close encounter with the Mink last Friday I have been fortunate enough to enlist the assistance of a local gamekeeper, and so I’ve been visiting the site twice a day to check the live trap we put down under the tree where I saw the Mink. So far it’s been empty each time I’ve visited and I’ll probably give it until the end of next weekend before returning the trap.

On the Kingfisher front, I sat in my bag hide today after arriving at about 17:30 to check the trap and watched the nest burrow. After half an hour I heard the familiar high pitched call from downstream and the male bird then flew in to perch in the tree opposite the burrow. he continued to call and after only a few seconds the female exited the burrow and flew across, perching on a branch about 10 feet above the male. She then called a couple of times and then headed off upstream. The male entered the burrow about 30 seconds later and after waiting a minute or two to ensure he was settled, I left my hiding place and headed home for dinner. We should be about half way through the brooding phase if my estimate is correct.

The water level on the river was well up today under the burrow, after some sharp showers yesterday. On a major river like the Trent flood water is a real danger to Kingfishers nest burrows, however, the water level is still a good 4 feet below this burrow entrance, so I think it’s fairly safe from flooding. Kingfisher burrows usually gently slope upwards and end in a small hollowed bowl about 3ft from the entrance.

Double jeopardy

The Kingfisher nest site has been the centre of a lot of drama in the last couple of days. Two serious threats to the Kingfishers have cropped up and although one has now been dealt with, the second is still present and I’m considering what can be done about it.

The first problem became obvious when I visited the site to observe the brooding behaviour on Thursday morning. From the opposite bank, I watched in horror as a herd of bullocks shoved there way past and even jumped over the fence protecting the area of the bank with the Kingfisher nest. The fence was put up a few years ago after cattle had stoved in the bank and destroyed a nest in 2004, so to be fair it wasn’t in great repair, however until today I thought it was still servicable. After driving round to the location where I access the bank on the Kingfisher side of the river I managed to lure the cattle away from the bank and then surveyed the damage.

I’d seen the cattle jostling and bucking directly above the nest hole, so I was fairly concerned and on examination a clod of earth was missing directly above the hole. On the plus side, the Kingfishers were still in attendance and I watched in some relief as the male entered the burrow and stayed in for a brooding session.

Once I’d established that the nest seemed to be intact I contacted the estate office and despite them being shorthanded over the easter weekend they were great and we managed to organise a fencing repair the same day. If we hadn’t repaired the fence, I feel certain that the bank with the nest in it would have been lost within days.

So on Thursday lunchtime we had the tractor down at the site and a new fence was erected. We kept the new fence posts as far from the burrow as we could, but I was very aware every time the posts were bashed in of the potential disturbance to the burrow.

So it was with some trepidation that I went down on Friday 6th to monitor the site from a distance using my bag hide. After half an hour I was really pleased to see the male emerge from the burrow and after a brief fishing session opposite the nest return to brooding duty. The male emerged from the nest 3 more times until finally, the female returned and entered the burrow. So, I still have both parents apparently brooding normally despite the disturbance.

However, the Kingfishers were not all that I saw on Friday.

I had been sitting in cover with my bag hide completely covering me for about 2 hours when I heard a noise directly behind me. I slowly turned round and through the small hole in my hide I stared straight into the face of an adult Mink sitting upright sniffing the air and trying to work out what I was.

After a few seconds it disapeared for a minute or two and then re-appeared and ran straight in front of me no more than 5 feet from my feet. It hopped over a tree trunk and then to my horror dropped down into the river and swam straight to the undergrowth right next to where the male Kingfisher has been fishing from a low perch in between brooding sessions.

I watched as the Kingfisher emerged from the burrow and perched no more than 6 feet from where I had last seen the Mink. After a few seconds the Kingfisher dove into the water, caught a fish and moved to a safer perch. After the Kingfisher had returned to the burrow I watched the Mink emerge from close to where the Kingfisher had been fishing and trot along a fallen tree branch overhanging the river.

Well, that was as much as I saw today. How much time that Mink is spending in the vicinity and whether it could create an opportunity to ambush the Kingfishers I simply don’t know. Either way it re-enforces my intention to protect the burrow from being dug out from above as it was last year, I just hope the adults are going to be OK. As I watched it bought to mind Charlie Hamilton Jones’s film Halcyon River Diary, where a mink ambushed a pair of fighting Kingfishers, so mink are certainly capable of predating adult birds.

On the plus side, when I left both adult birds are still present and behaving normally, the bank is now protected from the cattle and so far the Mink obviously hasn’t figured out a way to ambush them.

Brooding underway

Today’s visit marks another distinct phase in the breeding cycle. I spent 4 hours observing the nest site today on what has been a bright, if a little chilly morning.

In contrast to my last visit on Wednesday 28th March when the adults stayed mainly in the trees, only briefly visiting the burrow, today I watched as both adults took consecutive turns, staying in the nest burrow on brooding duty. With the mating and egg laying apparently completed, the next 3 weeks should see the kingfishers sharing incubation duties.

The first 3 changeovers I watched each consisted of 30-45 minute shifts. Each time they returned to the nest, they perched opposite the burrow and began calling, several seconds later the brooding bird emerged from the burrow and then they briefly perched together in the tree, both birds continuing to call to each other. After 20-30 seconds the returning bird flew across to the burrow to commence brooding duty while the other flew off to hunt.

The final changeover I watched had me a bit worried; the female was away from the nest, and after an hour she still hadn’t returned. The male emerged from the burrow after 1 hour 15 minutes for several minutes, calling and flying from branch to branch, looking slightly agitated before returning to the burrow. The female finally arrived back at the burrow after being away for over 2 hours (the male then vacated immediately and flew downstream, not bothering to stop and say hello).

As I can pin down the transition from laying to brooding to within the last 5 days I can predict reasonably confidently that the brood should hatch (assuming nothing disastrous happens) somewhere around the third week in April.