Strange morning

This morning's session was quite strange. On one hand the weather was perfect and after a couple of decent day of weather we were expecting a bit of a bumper catch. As it turned out the catch was a little disappointing with only 51 new birds ringed. However, on the other hand 48 of these birds were migrants and for the first time this season Sedge Warblers outnumbered Reed Warblers. Sedgies tend to set off on their migration a tad earlier than Reeds and at this time of year we often see a rise in their numbers--as we did today.

Just one close up picture today which MAY be of use in the field especially if you have a good telescope view of a Reed Warbler:-

You can see that the iris of this bird is distinctly lighter that the black of the pupil. This is a feature of adult Reed Warblers--a juvenile has almost no contrast with the iris and pupil being almost all black.

My second image has nothing to do with our ringing session--other than we had a few Swifts flying overhead before we finished the session. Thanks to Ron for sending me some pictures of these birds. Here is one I have cropped to show it in close up:-

The work I've done hasn't done a lot for the quality of the picture--but you CAN seethe strange lump below the bird's beak. This is the extended throat pouch which is obviously full of insects which this bird has been catching. It's also pretty strong evidence that this bird is breeding nearby because the adults fill these pouches before returning to the nest to use the contents to feed their growing chicks.

Another migrant fest.

Despite our problems with the weather forecasts, we still managed a cracking weekend of ringing at Belvide.
In summary we ringed a very respectable 94 new birds--of which 80 were migrants. The more numerous as usual were Reed, Sedge, Blackcap and Chiffchaff. But today we had our first Lesser Whitethroat of this season. These are always just that little bit special. Even more special was the Pied Flycatcher that turned up out of the blue. This is only the third individual of this species we have ringed at the res--previous ones in 2007 1nd 2016. Later in the day the Belvide birders found a second bird ( without a ring), making it a bit of a red letter day for us.

 

The shape of the white areas on the wing feathers confirmed that this was a juvenile bird--we wonder where it was hatched--Wales or Northern Britain. We may get to know if someone handles it again in a nesting area in future years.

 

 

This rear view shows the almost black tail, Our guides suggest that this is probably a juvenile male, although its difficult to be certain and probably safest to leave unsexed.

Several times on this blog I've mentioned ID or other features which are useful to ringers with a bird in the hand--but which are of no use in the field. There are lots of Willow Warblers about at the moment. Most of them are juveniles and it's relatively easy to age them in the field as they are mostly bright yellow on the whole of the throat and belly--as shown in this bird:-

 

In contrast, the adult birds at this time of year show a yellow throat with a mostly white belly ( sometimes with some feint yellow streaks) as shown here:-

 

 

Just beware Wood Warblers--they are even brighter yellow on the throat and gleaming white on the belly with much greener upper parts.

 

Looking forward to Wednesday's session--wonder what will drop in?

 

 

Weather forecasts!!??!!

Apologies that I forgot to post here that this morning's ringing session had been postponed. The fact is that I spent most of yesterday looking at weather forecasts of various brands and most were contradictory. It's a real problem when you have team members potentially travelling for over an hour to get here, because the last thing you want is for them to get here and find that rain stopped play.

I made the decision to postpone the session in time for team members to make alternative arrangements--but on waking at 6 this morning it wasn't raining!! Furthermore we could have had a full session as the rain didn't start till 10am and then only for a few minutes.

We are hoping that the weather will be ok for tomorrow morning...……….news about that later.

Things on the move!!

This morning was a big turning point in the migration season to date--after a couple of days of good weather, with gentle headwinds and increasing cloud cover during the night it was an almost perfect morning to sample birds that had migrated recently.
It was apparent that migration was under way when we ended at 10 am with 127 new birds ringed of which 101 were migrant warblers. Blackcap were the most numerous ( as they will probably continue to be from now on) with 35, Chiffchaff 21, Reed Warbler 15, Sedge Warbler 12, Willow Warbler 9, Garden Warbler 8 (!!!), and Common Whitethroat 1. In total we ringed 16 different species of birds--on top of which many of those present had their first ever view of a Water Shrew :-

This tiny shrew spent quite some time snuffling about in the vegetation beside the path eating insects before disappearing down into the ditch next to the path.

 

Birders often agonise over the separation of Willow Warbler and Chiffchaff--especially if they don't sing or call. Fortunately these species are relatively easy to identify in the hand--but the way we do it isn't too helpful in the field unfortunately. It's all about the shape of primary wing feather number 6.

 

The feather arrowed is primary 6 and in this picture you can see the outer web slopes in towards the shaft of the feather towards the tip--called 'emargination'. This is a CHIFFCHAFF wing.

 

Primary 6 on this wing has no emargination ( primary 5 has) so this is a WILLOW WARBLER.

Best of luck spotting this in the field!!

 

Exceptionally, some species ( for a reason I'm not aware of) adults and juveniles go through a complete moult of body, wing and tail feathers about this time of year. Long Tailed Tit is one such species. Once they have completed this moult its impossible to age this species--but just at the moment they are in the process of moulting and there are still clues as to whether birds are adult or juvenile--as shown in these two birds:-

 

Looking at the wings you can see that there are gaps and growing feathers where the wing feathers are actively moulting. However, if we look at the heads of the two birds:-

 

--you can just about make out that the top bird has brown feathers on the sides of the head showing it to be juvenile, and the bottom bird has black sides to the head-an adult. In a couple of weeks they will both look the same and unable to be aged by conventional methods.

 

It looks like the weather pattern may well be against us on Saturday with a possible wet period in the morning--I will post any change to our schedule on here.

 

 

 

 

That's more like it!

Another day of uncertainty yesterday as the weather forecast for this morning kept changing by the hour---again!!. In the end I had to make a decision and fortunately I opted to run the session. I'm really glad I did because apart from a short period of dampness when we closed the nets for a while, the conditions were almost perfect for ringing.
It became apparent that birds had started to migrate and by the end of the session we had ringed 87 new birds--far and away the most so far this season. Migrant warblers were well represented with 23 Chiffchaff, 16 each of Reed Warbler and Blackcap, 10 Sedge and 3 Willow Warblers.
We also caught a couple of juvenile Goldcrests and I've included a picture of one to help folk identify this species in juvenile plumage:-

As you can see in this view there is no yellow streak on the crown in very young birds, although in a few weeks this feature will be present--so beware at this time of year, it's still a Goldcrest.

 

We also caught a recently fledged Reed Warbler, and this view of its tail shows an interesting feature.

 

 

The different coloured marks on the tail are called either growth or fault bars. If you imagine this bird in the nest, all of its tail feathers start to grow at the same time-if the amount and/or quality of the food the parents feed the chicks with changes--this will be reflected in the materials used to grow the feathers. I can't say exactly what change has occurred in this case, but it may have been a cold/wet period when the parents had difficulty finding food and the growth bars appeared as a result--all lined up as the feathers grew in synchrony. We have seen some birds where this has weakened the feathers so much that all or most of the tail feathers have broken off at the fault line.  

 

Busy Week

Unfortunately the 'better weather' referred to last week was short-lived and this week we have been dodging the poor weather in order to carry on.
Having missed a session last week, a break in the weather on Monday afternoon gave Kev and I the opportunity to try late start replacement session with just a few nets open. It turned into a very rewarding visit, with just short of 50 new birds ringed--with evidence of a start of migration with increased numbers of Blackcaps coming through and our first Whitethroats of the season. A couple of juvenile Treecreepers proved that they have bred successfully on the reserve. And an adult male Moorhen was the first of the season:-

Close up these are actually quite stunning birds--the bright red base to the bill and 'shield', gives way to a bright yellow tip to the bill. Adults also have a red iris contrasting with the black pupil. This species can be sexed according to a combination of measurements of the leg and longest toe on one axis and the wing length on the other axis--this was a male.

On Wednesday Kev was out again with son Gareth at their Racecourse site and had a really nice catch of 25 birds including Blackcaps, Chiffchaffs and a Reed Warbler--but the undoubted stars were 3 juvenile Lesser Whitethroats:-

These intriguing warblers are of course migrants, but unlike most of our migrants they don't fly due south to Africa for the winter. Instead they fly south east to the far side of the Mediterranean, then down into the Nile Valley. The best way of separating this species from the Common Whitethroat is by the grey/brown wings --in Common they have bright chestnut brown wing feathers.

 

I foolishly believed the various weather forecast which predicted rain on Wednesday morning, so I cancelled the usual session--no rain fell. So we rapidly re-arranged a session on Thursday. The weather was still not great but we were able to operate and ended up with 45 new birds-still some evidence of migration but really only a trickle. Blackcaps are definitely on the move, and this bird was quite instructive.

All juvenile Blackcaps have a brown cap as they leave the nest--then over the ensuing weeks/months, the cap feathers are moulted out being replaced by brown feathers for females and black for males. This bird is a juvenile male--the wing feathers are in good condition having just fledged in them--but already most of the juvenile cap feathers have been replaced by black ones-although you can still see some brown ones present. We reckon this was probably the result of an early brood and it's parents are probably now rearing another nest full of hungry chicks somewhere.

More rain predicted for Saturday--will we get in a session, or will we move it to Sunday? Who knows at this stage?

 

 

Kev finally connects!!

It was a lovely morning for our latest Belvide session this morning--we hope it means that migration will start to get underway soon bringing lots of lovely birds to our reserve as they move south. There's not much sign of that at the moment--although to be fair, the very poor weather over the last week will have supressed much of the migratory urge.
It was a rather predictable catch this morning of 57 new birds--mainly Reed and Sedge warblers with a smattering of other species. We also recaptured about 40 birds which had been ringed previously; suggesting they are still in the area and haven't yet started to migrate south. One very welcome bird was a very recently fledged baby Cetti's warbler. The significance of this for our reserve is that it definitely proves that a second brood has been reared by our birds who raised the first ever brood of Cetti's earlier in the year. It's still not yet mid-July so ( although the books suggest they only have two broods maximum) there's still time for them to have a third brood--we hope.
Birders often have one or two 'bogey' birds--relatively common birds which seem to avoid being seen. Similarly ringers have the same--ie birds which avoid being caught for ringing-at least when they are they. For one of our more experienced members, Kev, the Marsh Tit is one such species, so it was great for the team this morning to see Kev finally connect with this delightful species.
We usually have only one or two breeding pairs on or near the reserve each year--so there are never many of these birds about. The bird we did catch this morning was a recently fledged individual, and this picture of the bird perched on a branch is rather instructive.

 

First-look at the 'fluffiness' of the bird. This is because the first set of feathers birds have as they leave the nest do not have many barbs on their feathers so they are not as sleek as the feathers that grow through as the bird develops.

Second, the guide books will tell you that Marsh Tits are supposed to have glossy black caps--this one is decidedly matt black. Again this is an ageing feature--over the coming weeks, these head feathers will moult out and be replaced by shiny black ones.

Last, separating Marsh from Willow Tit is a challenge for anyone--especially if they don't sing or call. This Marsh Tit shows a characteristic which really helps ID it. The upper mandible of the beak has a white area above the cutting edge near the head. Not all Marsh Tits have this but if it's there it IS a Marsh because as far as we know Willow Tits never have this feature.