Spring Ringing at Bedfont Lakes

It’s all go at Bedfont Lakes as we start this years CES (Constant Effort Sight Scheme). At the main site (the nature reserve on the north side) the reed warblers have returned and are still settling in whilst breeding is in already in full swing for some of the other species. We had our first fledglings of the year over the last two weeks, a species which also happen to be one of the cutest; long-tailed tits in their juvenile plumage, complete with their dark chocolate brown (super hero style) face masks. Fighting against injustice towards all thing small and fluffy 😉

Juvenile long-tailed tit with dark face mask

Juvenile long-tailed tit with dark face mask

IMG_1715Surprisingly we have yet to catch any robin or blue tit fledglings which are usually one of the earliest species to breed. I suspect the blue tits are out there somewhere considering the stage of the brood patches on some of the adult females we have caught. There are a few sedge warblers around (my personal favourite) as well as the resident Cetti’s from last year (let’s hope for another year of breeding success!), blackcaps, chiffchaffs and a couple of garden warblers ringed a few weeks ago. A nice surprise was this lovely male whitethroat, a species usually only caught at the South Side of the park.

Whitethroat

Whitethroat

IMG_4781Another rare catch was this treecreeper from 3 weeks ago, only the third we have caught since I started in January 2014. They are just exquisite up close! Such beautiful markings.

Treecreeper

Treecreeper

We’ve also managed a couple of visits to the South Side of the park this month and last which produced one exciting and one very very exciting (a first for this site) species. Both I’ll admit are prone to being described at ‘dull’ looking birds, however I tend to disagree especially in relation to the former; this very smart looking lesser whitethroat.

Lesser whitethroat

Lesser whitethroat

The latter species? Last, but certainly not least, after my trainer suddenly stopped in the middle of putting the nets up and swore he heard a nightingale singing (despite being the ripe old age of 75 he still puts my bird song ID skills to shame)…. Guess what our very first bird of the day was??? A species I’ve only ever heard in the lovely surroundings of Blean Woods and would never dream of seeing just a few miles away from my house! I’ll confess I really did know what it was at first, somehow I expected them to be bigger, amazing the perspective you get from having the opportunity to get up close to these birds. The rufous tale is a good indication, although it was a lot subtler than I was expecting. Yes a ‘little brown job’ but still a beautiful one and certainly a rare treat!

Nightingale!

Nightingale!

IMG_4749Other none bird related sightings include a lovely little micro moth Ptycholoma lecheana whose beautiful metallic markings caught my eye last week, at least 2 grass snakes seen sunning themselves on the board walk and a brief glimpse of a green hairstreak that I got rather excited about at South Side two weeks ago – just one individual as far as I could tell so I’m not sure if this was an anomaly or if their is a colony of them, either way the sighting was certainly an nice unexpected surprise (the best kind!). We’re back there next week so I will have a good search around.

Ptycholoma lecheana

Ptycholoma lecheana

So really it’s been a very exciting couple of months! I have only one more to go before I leave to spend the rest of my summer on Skokholm Island. As excited as I am I will miss this lovely little unassuming place and the way it never ceases to excite and amaze me; a haven for birds (and for me) in the middle of all this concrete and noise.

Warblers of Bedfont Lakes

After a fantastic spring and summer of bird ringing at Bedfont Lakes most of the warblers (aside from the resident cetti’s warbler) have left for their long journey to their wintering grounds. Before they leave they have a fair bit of fattening up to do so this is the time when ringers start  noting the weight of these migratory birds and giving each individual a fat and a pectoral muscle score. This is a new learning experience for me and a few weeks back was a great opportunity for me as we caught over 102 birds at Bedfont Lakes South Side between 4 of us (and sadly I had to leave early that day!), including 36 blackcap and 25 whitethroat! This allowed me to compare individuals varying fat and pectoral muscle build up and get to grips with how they feel and look.

I thought this would be a nice time to look at some of the different species of warblers at Bedfont and some of the differences between the juvenile and adult birds. Starting with my favourite – the sedge warbler.

Juvenile sedge warbler

Juvenile sedge warbler

As far as I figure, generally juvenile sedges have more yellowish buff colouring especially on the underparts but from the photo above it is hard to tell if this is indeed a juvenile or an adult (I found it tricky!),  you would need to look closer at the feathers; new, fresh wing and tail feathers and ‘fluffy’ under tail coverts can sometimes be a giveaway, although not always obvious to me. With this species a good clue is the spotty ‘necklace’ most juveniles have – not so much in the one pictured above but you can see here in the one below a line of small dark spots going across the breast.

Juvenile sedge warbler with 'necklace'

Juvenile sedge warbler with ‘necklace’

Really these are beautiful birds, their creamy colouring and dark markings are just fantastic. Definitely have a soft spot for them!

Reed warblers seem to be the most common warbler ringed at the main sight (the Nature Reserve on the North side of the Park). Again new, fresh wing and tail feathers and ‘fluffy’ under tail coverts can indicate a juvenile bird but also in this species the juveniles are usually a more rufous or rusty colour, especially on the upper parts and rump as you can see in this next photo (juvenile on the left).

Juvenile vs adult reed warbler

Juvenile (left) and adult (right) reed warbler comparison

Another indication of age with this species is eye colour – the iris is a grey charcoal colour in their first year then changes to a more olive brown as you can see in this adult bird.

Adult reed warbler

Adult reed warbler

I haven’t managed to get a good photo showing the iris of a juvinile reed warbler but i did get this adorable one of a very newly fledged bird, how cute?! He hasn’t even grown his tail feathers yet!

Juvenile reed warbler

Reed warbler fledgling

Only a little bit more developed is this rather fluffy juvenile cetti’s warbler…. This year was the first record of cetti’s breeding at this site!

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Juvenile cetti’s warbler

Again the juveniles in this species have a darker grey iris as opposed to the brown iris of the adults.

Another common warbler species at bedfont are blackcaps. I mentioned in previous posts (this one and this one) that the juveniles have a duller brown cap, as opposed to the chestnut in the adult females and black in the adult males. The juveniles are are generally more brown and fluffy compared to the adults and have fluffy undertail coverts that are a light brown (or ‘mocha’ as I call it!) colour as opposed to grey in the adults.

Juvenile blackcap undertail coverts

Juvenile blackcap undertail coverts

Blackcap fledgling

Juvenile blackcap

Adult female blackcap

Adult female blackcap

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Upperparts of adult female blackcap

In the last 10 months I have been ringing at Bedfont I haven’t seen many willow warblers but I know the juveniles generally have more yellow underparts and generally brighter yellow colouring all round. This juvenile is a good example, and stunning in in the sunlight!

Juvenile willow warbler

Juvenile willow warbler

Juvenile willow warbler

Juvenile willow warbler

In my experience ringing at Bedfont other warblers that seem to be fairly common are chiffchaffs and whitethroats, the latter only at South Side. Along with willow warblers, other warblers not as common are garden warblers and lesser whitethroats. In fact I think I’ve only seen a handful of adults. In any case, it was a treat as they are both beautiful, smart looking birds – not at all ‘grey and dull’!

IMG_1136

Lesser whitethroat

IMG_1654

Garden warbler

It’s been an amazing spring and summer and now I am looking forward to see what new learning experiences autumn and winter bring!

A Willow Warbler, a Wriggly Wren and a Not So Lesser Whitethroat

Hi all,

I had a beautiful sunny morning bird ringing at Bedfont Lakes south side this morning!

We caught our first Willow warbler of the year, it was great being able to get up close to these birds and compare them to their close cousin the Chiffchaff. What surprised me what just how different the wings are in shape and length – the willow warbler has much longer, more pointed wings where as chiffchaffs are short and rounded. I’ll try and get a good comparison photo for you! In the meantime here is a blog post with a great photo.

We also caught a lovely Wren. They are one of the trickiest to extract from the net as they are so small, rounded and wriggly! Such handsome birds, here is a photo of one we caught a few weeks ago.

IMG_0848To age a bird you need to gauge the state of molt the bird is in thus what stage of life it is at. This means looking for a difference in old and new feathers which could be in shape, colour, pattern or the amount of wear and tear (this is a good read if you are interested). Simple, right? No! This skill takes years and years to perfect and even the most experienced ringers can still find it tough…..

Luckily with wrens there is a little trick I learnt – the rule is 10 or more spots on the  outer edge of 4th primary feather means it is and adult bird (so that would mean born before last year) and 8 or less spots and it is a juvenile bird born last year. What if the birds has 9 spots? Then your guess is a good as mine 😉 IMG_0849So, any one want to have a go at ageing this bird?

We also caught this stunner.IMG_1136A Lesser whitethroat. This photo does not do it justice! Not ‘just a grey bird’. It was great to see one up close – they are secretive birds and I’ve never got much of a good view of one before.

I almost forgot, just when we were packed up and about to leave a swallow flew over! My first of the year, spring is officially underway 🙂