The cold spell we are having has resulted in shallow lakes such as Østensjøvannet and Bogstadvannet and marshes to freeze over as well as making the ground rock hard. Maridalsvannet which is much deeper is still ice free although ice is forming at the edges. This weather means that any remaining snipe or Woodcock are going to have a hard time. My nocturnal trips into Maridalen with the thermal have not revealed any Woodcock for a week and Jack and Common Snipe have gone from Fornebu. However, this is the time when any birds that have not fled south can be found seeking refuge on suitable streams and ditches and a visit to one such stream revealed singles of Jack and Common Snipe this week. With the forecast being for a temporary return to warmer weather next week these birds may have made a good decision to remain although to survive the whole winter here will be exceptionally tough for them.
All snipe have a very similar plumage which is a very
effective camouflage however they rely on this camouflage to varying degrees.
Common Snipe will freeze when they spot a potential predator but will then fly
up at 5-10 metres range and often then fly a fairly long distance. A Jack Snipe
on the other hand will usually freeze against the ground and trust that it is
invisible to such an extent that it doesn’t fly up until it is almost trodden
on and will then often fly a relatively short distance before landing. I have
often wondered why the species have such different strategies but feel like I
have had a breakthrough in my own understanding now.
When I found a Jack Snipe it was as usual frozen to the
spot. I know from experience that it will do nothing whilst it can see you so I
decided to continue along the stream to see if I could spot anything else.
About 50 metres further along a Common Snipe flew up before I had even seen it
and headed along the stream without me seeing if it landed. I then returned to
the Jack which was of course frozen to the spot but it wasn’t exactly the same
spot so it had clearly moved when I wasn’t there. I decided to set up my camera
on the tripod and operate it via my ipad from a safe distance. This allowed me to
see that once I had moved out of view the bird remained frozen for a couple of
minutes before it gently started bobbing before then really coming to life and
preening and then feeding. If it heard a threatening noise it would stand still
before resuming bobbing once it was sure there was no threat. I tested how it
would respond to me moving into its view and it could be seen to shrink,
flatten itself to the ground and freeze. All this can be seen in the video I
took.
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| the camera in place by the stream |
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| and using an ipad to control the camera |
So, what is my breakthrough insight? Well, Jack Snipe often try to exploit quite marginal habitats and if they were to fly off when disturbed or threatened then they would not necessarily find another suitable habitat and would miss out on lots of feeding time and use up energy unnecessarily. By freezing to the spot and waiting for the danger to pass they can resume feeding in their chosen spot more quickly. Of course there is a risk that the predator will locate them and grab them before they chose to fly off at the last moment but I guess evolution has resulted in that risk being small enough. But why do Common Snipe not do the same? Well they are larger and therefore it is not as easy for them to just blend in and disappear as well as the Jack does so presumably they have learnt that they face a higher risk of being spotted and taken? This is just my musings but I feel there is some truth in it.
The edited video is 3 minutes 14 seconds long but in my own
humble opinion is well worth watching all the way through. I posted a 17 second
snippet on Twitter and it has become my most popular posting ever.
Oslo is having its first cold spell of the winter and shallow lakes and marshes are now frozen. Any remaining snipe have either had to flee south or seek refuge on suitable streams.
— Simon Rix (@si_rix) November 21, 2024
This Jack Snipe has chosen the later and allowed itself to be filmed bobbing and feeding today. pic.twitter.com/F5gqFTMnWI
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| as usual I ask the question - can you spot the Jack Snipe (kvartbekkasin)? |
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| this was my clue to the fact there was a snipe on the river - probing beak marks in the mud and a white dropping |
Simon, I used to find a lot of Jack Snipe in winter when I was in the UK. One observation I made was that they were rather picky in their habitat. Whereas Snipe could be found in wide variety of marshy vegetation, Jack Snipe had a strong preference for vegetation that was quite short (4-6 inches). Often they would be concentrated in such spots and not found at all in adjacent areas with extensive juncus or higher vegetation. An alternative theory to your one might be that given that such habitat was often rather limited, easily flushing from it would inform predators that potential prey was at that location and encourage repeated checking of the limited preferred habitat. It never ceased to amaze me that I would walk into a patch of their favorite habitat and assure myself that there were none within a few feet of me only to flush 2-3 with my next step!
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