Siskins in short supply.

Things had been looking quite promising for Siskins in the garden this spring with birds starting to visit the feeders back in late December and then more regularly through January and into early February. Up to five were seen visiting the feeders in late December and that increased to between five and ten through January and into early February but then numbers fell away. That sudden and unexpected drop off in numbers was also mirrored by Goldfinches and other species so it wasn't just a Siskin thing which makes it a bit harder to understand.

The prospects for the spring looked to be good at the end of January with up to 10 Siskins visiting the feeders.

This is one of 7 feeders in the garden. All were well used in late January and needed topping up or filling every day.

The drop off in numbers of all species started ahead of the spell of exceptionally warm weather that came in late February but that doesn't mean the weather wasn't a factor. Temperatures could be involved as it has been quite a mild winter overall but wet or dry conditions can make a difference too. Cones on alder and conifers open and close in response to moisture levels which can make their seeds more or less easily accessible and their productivity also varies from year to year. The mild conditions have caused some tree buds to develop early and willow catkins to emerge which are another energy rich food source for Siskins and other finches. The fact that Siskins are variable migrants in terms of numbers and distances involved and can be very early breeders all adds to the complexity but it is all food related in one way or another. Bottom line it is currently looking like being a relatively poor spring for Siskins in my garden this year. Currently a maximum of three are visiting the feeders at any one time and then only on a fairly intermittent basis. If it was going to be a good spring for Siskins I would expect counts to be in double figures by now (18 were ringed in the garden on 6th March last year) with birds being seen in the garden throughout much of the day.

Ringing revealed there were a few more Siskins visiting the feeders than the counts alone had indicated, as is often the case, but the overall picture was the same. At least 7 different individuals visited the feeders in late December and one of those was a retrap that was originally ringed in February 2018. In January and February a total of 16 different individuals were captured: of these 12 were new birds, 3 were retraps that had been ringed in December and another retrap had been ringed in December 2017. In the past Siskins were exclusively late winter and spring visitors to the feeders but the last few years have seen small numbers arriving much earlier in the winter with some being ringed returning birds. It will be interesting to see if this trend of early arrival and winter to winter retraps continues or even increases in the coming years.

Male Siskin 31/01/2019.
I took a series of photographs of this bird and managed to read part of the ring number which pointed to it being one of the returning wintering birds.

Female Siskin 31/01/2019

There is still time for numbers to increase as we move further into spring but any build up in numbers will be much later than usual and is likely to involve fewer birds than last year, if it happens at all.  

Siskin Summary

It has been a reasonable winter and early spring for Siskins in the garden and it isn't over yet. The first Siskins were seen on the feeders back in late November which is relatively early for my garden and, interestingly, both were adult males and both were already wearing rings. Counts stayed in single figures through December, January and the early part of February, although ringing showed there was a little bit of  turnover. Numbers increased in the second half of February and peaked in early March when up to 20 were counted but there was some turnover over the course of each day so the actual peak was probably closer to 30. Counts fluctuated markedly through the middle of March and continued fluctuating as numbers dropped off through the latter part of the month. That brings us right up to today when 5 were present.

Adult male Siskin ringed 28/03/2018

A total of 77 have been ringed and there has been 1 control and that had been ringed 4 days earlier at a site 6km away. Regular readers of the blog will know I have photographed several birds that were ringed prior to this winter and although I wasn't able read the full ring numbers I could read enough to be reasonably confident that they had been ringed in the garden. Frustratingly, they all managed to avoid being recaptured but a different returning bird was retrapped recently; S144917 had been ringed on 19/04/2016 and was retrapped a couple of days ago, on 28/03/2018.

Adult female Siskin S144917 was originally ringed in the garden on 19/04/2016 and retrapped there on 28/03/2018

I have had similar retraps in subsequent years before and they are interesting because Siskins are irruptive migrants. The proportion of the population that migrates and the distance they move varies from one year to the next in response to the availability of food. In some years, like autumn/winter 2014/15, they don't migrate and are able to stay on or very near their breeding areas because of an abundance of natural food. I didn't get any Siskins in my garden that winter or in the following spring, as was the experience of most ringers. The recapture of birds from one winter or spring to the next or after intervals of more than a year shows that some birds use traditional routes and traditional feeding sites, including well stocked gardens like mine, but only when they need to move that far.

Savvy Siskins and Sneaky Snipe

In an previous post I mentioned how Siskins had started visiting the feeders in my garden much earlier than usual this winter and that the first two seen in late November were already ringed. I speculated that both were likely to be returning birds rather than having been ringed elsewhere and I thought I would be able to confirm that by retrapping one or both of them within a relatively short space of time. I have caught 11 Siskins in the garden since then and over 100 Goldfinches but haven't caught either of those ringed Siskins, both of which were adult males, or any others that had been ringed prior to this winter, let alone ringed elsewhere. Now that I have ringed some Siskins this winter it isn't possible to say a bird could be a returnee by the mere presence of a ring as I was able to with those first two males.

It is fair to say that I am both surprised and disappointed that I haven't retrapped either of those ringed Siskins and that disappointment has been compounded by two I have photographed recently. I have got loads of photos of Siskins, some of which are really quite good, but that doesn't stop me from trying to take more, and I have done a bit of 'snapping' over the last week or so. When I review photographs I always look to see if I can read any rings, if present, and I managed to read part of the ring numbers of a couple of Siskins and, surprise surprise, they weren't birds I had ringed this winter. The first, a male photographed on 24th Jan, was wearing ring that started Z0..... which is the start of a sequence that I was using in the garden 2 to 3 years ago and certainly not this winter. The second was a female with a ring inscription that started with the letter S...... and another photo showed more of that ring number which pointed to it having been ringed in the garden last January.

Z0........ male Siskin

The other photos of this bird revealed more of the ring number which, by a process of elimination, is almost certainly a bird that was ringed as an adult female on 22/01/2017

I have no way of knowing how long they have been visiting the feeders but there is a chance the Z0....... ringed bird could have been one of those initial males. What I can say is that at least 3 Siskins, ringed prior to this winter, have visited the feeders and that all 3 have evaded recapture to date. Their ability to avoid being caught strengthens my view that they are all returning birds and that they are quite savvy when it comes to avoiding a mist-net in my garden because they have seen it all before. Net shyness, as it is sometimes referred to, is not unusual and is most common in resident birds or at times when a population becomes relatively static such as birds visiting feeders in winter and is something I try to minimise in various ways, so it is interesting that these Siskins appear to have remembered or perhaps I should say retained that level awareness despite being away from the garden for over 7 months. Obviously there is still a chance that these birds will end up being caught at some point later this winter but I wouldn't like to bet on it.

Regular readers of this blog may remember some photographs of Snipe roosting in a field of winter cereal that I posted on the blog last winter (link here). Snipe roosted in this field from November (when they were first found and up to 29 were counted) through to at least mid-January (when the crop started to grow and made the birds harder to see). I had never seen Snipe using an arable crop as a daytime roost site before and, knowing how traditional Snipe roosts usually are, I wondered if they would use the field again, especially if the type of crop changed. As things turned out the field was sown with rape in the autumn and I thought that change, and the fact that rape has a different structure, can get denser and a bit taller than autumn sown cereals during the winter, may put the birds off.

I didn't spot any birds using the field during November and the density of the crop meant any birds, if present, had a much better chance of remaining unseen, especially if they had chosen a different part of the field to roost in. It started to feel like I was looking for the proverbial needle in a haystack but I continued to scan the field from time to time. I probably could have got permission to do a walk through survey but it would have been very difficult to find a time when other people weren't around and I was concerned it may have drawn others to think it was OK to do the same, so I decided to stick with observations from the adjacent public footpaths to be on the safe side. Unfortunately there is trend for people in this area to think it is OK to walk around the headland of just about every field and even walk through crops with their dogs rather than sticking to the numerous public footpaths and public open spaces.

Anyway, I happened to be scanning the field about a week ago, on one of this year's rare sunny days, when I noticed a Snipe amongst the rape and it was in the same part of the field that the birds used last winter. Further observations revealed a few more and I eventually counted 10. A few days later I could see a similar number in the same area when a loud bang and some crashing from a building site about half a mile away caused a few more birds to pop their heads up and I ended up counting a minimum of 19. Unfortunately I didn't have my camera with me on either occasion but I have managed to get some images since.

The images above give you an idea of how difficult the are to see but it gets a bit easier once you get your eye in. I am sure they have been using the field all winter and that I have simply overlooked them until recently. If you think they were quite difficult but want a real challenge have a look at the series of images below. 

Spot the Snipe, not that you have any chance of finding it in this photo.

Try again in this zoomed and cropped image but I wouldn't waste too much time trying.

Same image again but even with a nice red arrow pointing it out you will probably struggle to see anything identifiable as a Snipe.

.....and here is a tighter crop of the same image and you can just see the distinctive crown stripes of a Snipe's head. Now that was a difficult one.

I certainly believe the use of this field by Snipe in successive winters qualifies it as a traditional roost site (and Snipe could have been using it prior to last winter) but it remains to be seen how long this particular winter roosting tradition can survive in the face of modern agricultural practices and crop rotations.

Unusual retrap

I have been neglecting the blog a bit recently but hopefully there will be regular updates now that autumn migration is gathering pace. I have been out and about whenever time and the weather have allowed and have caught 127 new birds and 18 retraps of 22 species since my last post. It is not a big total but its not bad considering the way the weather has been up here. The top five species ringed over the period (14th - 20th July) with retraps in brackets were: Swallow 24; Willow Warbler 18 (1); Chiffchaff; 18 (2); Goldfinch 11 (2); Tree Sparrow 9 (1).

The most unusual capture was an adult male Kestrel that was caught in a mist net at Crawford. I don't catch Kestrels very often and I have often gone years without catching one but this was even more unusual because it was a retrap. It was a bird that had been ringed at the same site a few weeks earlier, on 21/04/15. This year has been very poor for voles, their main food, so I can only assume this particular Kestrel has taken to feeding on small birds coming to the feeders at Crawford or the population of small mammals is doing better in the vicinity of the feeders because of the constant supply of seeds. Perhaps it is a combination of the two factors but it certainly is an unusual recapture.

Adult male Kestrel recaptured 20/07/15

Waxwing lyrical part 41 - returning bird confirmed !!!

There were no sightings of the Waxwing yesterday and none this first thing this morning but when I came home from Preston this afternoon she was sat feeding on an apple only a few feet from one of the upstairs windows. I ran inside and grabbed the camera, which I had left by the window, and started rattling off some shots. The bird was too close to the window to risk opening it and she clearly knew I was there even though the blinds were left two thirds closed. There was no ring on the left leg and her right leg was obscured and if she was a returning bird that is the leg she would most likely have a ring on. Happily I didn't have to wait long before I got a glimpse of the right leg and I could see she was ringed. I already suspected she was returning bird from 2013 but now I had to prove it by getting the ring number with photographs or by catching her.

Waxwings have fairly short legs and they can be difficult to see and especially when you really want to see them.

Go on show us your right leg.

Eventually she turned round and I could see a ring on the right leg.

Every timed she moved in the process of feeding and showed her ringed leg I hit the shutter button and took a burst of shots. The light levels were very poor and I was only getting fairy low slow shutter speeds of around 200th of a second much of the time which is a bit slow for hand holding a big lens and getting reasonably sharp shots of a moving subject. However I reviewed some of the photos on the back of the camera and could see I was able to read part of the ring number on some of them. Now I had to hope the ring would move around on her leg as she moved so I could read the full sequence of two letters and five numbers.

After taking around 180 photos in about 30 minutes I had the full combination of BV05864 and recognised it as being a sequence I had used. I looked up the details and found it was a bird I had ringed in the garden on 23/02/13 as a first winter female. I had also retrapped her on 28/03/13 so she was a bird that had stayed for a while and probably much longer than that as some birds stayed into May 2013.

Just a few of the photographs used to confirm the ring number.

If you have read my previous post (link here) you already know I thought it was more than just a bit of a coincidence that this bird found the apple halves in the garden (especially as there were only 3 for it to find). It made sense to me that a returning bird would go to areas it had frequented previously especially if there had been a very reliable food source and more than a ton of apples over 3 months must count as that. Returning to such areas also increases the chance of a bird finding others of its kind if such behaviour is an inherent trait.

I think Waxwings probably develop 'the knowledge' of finding their way around a bit like London cab drivers but on more of a continental scale and learning to find food sources rather than addresses. Their irruptive wanderings are probably less random than they often appear to be and the regularity of there occurrence in places like Aberdeen possibly goes some way in showing that. The return of this bird almost has similarities to a matriarch Elephant falling back on previous experience and leading the heard to a distant but reliable watering hole in a drought year.

That analogy to an Elephant may not be stretching things as much as you may think. The main differences, apart from size. feathers, wings, ears etc. etc., is Waxwings obviously have much shorter life spans and they may not be forced to undertake a long distance irruptive movement more than once in their lifetime so the opportunity to display such behaviour (knowledge) may not occur very often. Big Waxwing irruptions can be around 10 years apart and the average lifespan of a Waxwing is probably much less than that. Another complication is that movements may involve birds from different parts of their breeding range in different irruption years. Also the berry crop here can vary in irruption years too and even good berry crops may only last a few weeks. Basically the variables for a Waxwing are far greater than for the Elephant in a drought situation but the ability to learn and remember to enhance survival are fundamentally the same. You also have to add to that the fact that Waxwings aren't that well studied and relatively few are ringed and perhaps more importantly attracting them with supplies of apples over a long period is a relatively recent phenomenon.

Bottom line I think this is a fantastic occurrence and especially in a winter when there are so few in the country. It is clearly not here by chance and although there are risks with drawing any conclusions from single examples I am more than willing to stick my neck out with this one.

On the look out for danger above. Single birds have to spend more time looking out for predators compared to birds in a flock.

Stunner.