30/08 Thatcham Marsh LNR

Location: Thatcham Marsh LNR CES Visit 2026.12

Session:   30/08/2026 06:00 to 11:00hrs

Present:   IW, JL, RAD, JHW, IQ.

Weather: Overcast early clearing to sunny, returning to low cloud at end of session.

Nets: 192M net along the reed bed ride (net lengths 1A & 2A) up from 06:30 to 10:30hrs.

Lures:   (none)

Grasshopper Warbler – fledge this year.

Notes: The Grasshopper Warbler was an unexpected find in the net. We last had one here in 2023 and before that 2017. Willow Warber here is also unusal this decade. We regularly ringed a few (latterly on passage only) each year in diminishing numbers until 2016, after their occurance on this site spring and autumn has become sparadic; the last ringed here before today being a single in 2022. Mostly the changing habitat from low and scattered scrub in the dryer areas to mature trees and woodland is a major factor. Comparison with 2025 matching visit 12 in the table below highlights the lack of juvenile Reed Warblers, an indication of a poor breeding outcome. As can be seen in the following chart it is not the  lowest juvenile total though 2007 was also a poor year. 

Note we started the Constant Effort Site regime in 1993 and except for the 2020 covid year we have carried out all 12 of the required visits and the chart below indicates reed warblers encountered on those visits only.

CES visit 2026.12 Recaptures: (04)

Cetti’s warbler ringed: 12/07/2025, 21/06/2026.

Wren ringed: 25/07/2026, 22/08/2026. 

Sightings: A passage Spotted Flycatcher was the highlight of the morning with the Grasshopper Warbler and Willow Warbler all on passage. Heard a Water Rail calling near the reed bed ride; we have not detected them on the last one or two visits. 

25/08 Greenham Common

Location: Greenham Common - Western Enclosure 2026 wk35-Tue.

Session: 25/08/2026 07:40 to 10:50hrs.

Present: IW, JL.

Weather: Sunny bright,  breezy, warm.

Nets: 48metres 3 Rides, up from 08:00 to 10:30 hrs

Lures audio: (BC-CC-FC-GC-GW-WH-LW-WO),(W-WC-RT-SF-TP-YW),(GH),(YB),(RT), intermittently. 

One  of today’s Willow Warblers – a 1st summer individual, possibly one the last we'll see this year.

Notes: It was breezy today which probably inhibited the number of birds captured. Interestingly we have not ringed a Garden Warbler since week 33 whereas we usually get one or two through until week 38. Similarly, Whitethroat none since week 33 and week 34 is usually a peak year for the passage of this species after which numbers drop very steeply to week 37 with the occasional stragglers some years to week 39. Unfortunately, the weather looks to be unsuitable for the rest of this week when much needed rain is forecast.

Recaptures: (01)

Robin: ringed: 30/06/2026

Sightings: The first Jay(s) heard here for a few weeks; they have been unusually quiet so far this year. No Buzzards seen today which is unusal. IW thought there was a Redstart in the scrub near the ringing station, but it disappeared before he could be sure. The Fox looked to be a youngster according to RA who saw it south of the enclosure. He also said there were many Swallows perched along the Bunker fence.

22/08 Thatcham Marsh LNR

Location: Thatcham Marsh LNR CES Visit 2026.11

Session:     22/08/2026 06:00 to 11:00hrs

Present:      IW, JL, RAD, JHW, NC.

Weather:    Sunny with some cloud, calm, cool early warm later..

Nets: 192M net along the reed bed ride (net lengths 1A & 2A) up from 06:30 to 10:30hrs.

Lures:   (none)

Long-tailed Tit – unlike most passerines both adults and juveniles do a full moult August/September. Once this is complete it is not possible to separate them by age and they all become aged 2 code (all we know age-wise is that they are fullgrown).

Notes: We were able to unlock the gate today, the additional locks and who installed them is a mystery. Yesterday when I checked, the master lock had again been over-riden, fortunately this morning the chain of locks was in the correct configuration. It seem that some users  don’t realise they have missed out a lock. I had borrowed a key to one of the other locks just incase though. The ride is quite overgrown despite two interim tidying up sessions this season. For much of its length the phragmitres reed etc is the highest we can remember, being above the top of 2.7metre high nets. With their roots in water the very hot weather of late has caused accelerated growth of the reed, nettles and other plants. Fifteen of the 27 total were in the nets at nets down. Before this ringing was slow with few bird in or about the reed bed. Probably the most difficult extractions were a Common Hornet and a very large Bumble Bee; the latter stung me on the thumb which was quite painful.

FG = age indeterminate

CES visit 2026.11 Recaptures: (05)

Cetti’s warbler ringed: 05/10/2025, 02/08/2026.

Reed Warbler ringed: 25/07/2026.

Wren ringed: 03/07/2022, 21/06/2026. 

Sightings: A high flying Sparrowhawk early otherwise much as expected though we don’t often see

Mute Swan over here now. When the stream was clear of reed a family bred further upstream and

would sometimes venture down adjacent the net ride. One session one got trapped on the net ride

and was ringed – a unique occurrence for CES ringing.

21/08 Greenham Common

Location: Greenham Common - Western Enclosure 2026 wk34-Fri

Session: 21/08/2026 07:40 to 10:50hrs.

Present: IW, JL.

Weather: Sunny some cloud, light breeze, cool early warm later.

Nets: 48metres 3 Rides, up from 08:00 to 10:30 hrs.

Lures audio: (BC-CC-FC-GC-GW-WH-LW-WO),(W-WC-RT-SF-TP-YW),(GH),(YB),(RT), intermittently.

 

Blackcap -Female and Male

Notes: A bit of a Blackcap morning this session. We also are doing well for Blue Tits here this year, our total to date of 65 already exceeds some year totals for the whole of the week 24 to week 45 period.  Interestingly a similar capture to last years wk34 matching visit except the 2025 visit had better species variety.

Recaptures: (2)

Blackcap: ringed: 25/07/2026 (Thatcham Marsh LNR)

Blue Tit: ringed: 31/10/2025

Sightings: Apart from Blackcaps many of which were already in the scrub when we arrived and before the lures were turned on, very little else on the move. The Grey Wagtail flew west at nets up. There were a few more “resident” species about than of late such as Robin and Stonechat. One or two finch types flew over quite high but remained brown jobs as they didn’t call and we couldn’t see any plumage features. The Small Copper was the only butterfly seen.

18/08 Greenham Common

 Location: Greenham Common - Western Enclosure 2026 wk34-Tue

Session: 18/08/2026 07:40 to 10:50hrs

Present: IW, JL, JHW.

Weather: Overcast, warm, light breeze; bit of spotting early but no sign of any rain despite the low cloud..

Nets: 48metres 3 Rides, up from 08:00 to 10:30 hrs.

Lures audio: (BC-CC-FC-GC-GW-WH-LW-WO),(W-WC-RT-SF-TP-YW),(GH),(YB),(RT), intermittently.

One  of today’s Willow Warblers - a 1st year bird; adults having left soon after young fledged.

Notes: Overcast with low cloud and a bit of spotting but still warm. Just a steady flow of birds mostly Blackcaps (8) and Willow Warblers (3). Fewer birds than last year’s matching visit and less variety.

Also, should you be wondering why no CES visit 11 report for last weekend, it’s because we were locked out, not the best experience after getting up at 05:00hrs on Saturday – somebody had added a new lock bypassing the master lock and apparently it is not the fishermen or BBOWT; hopefully it will be dealt with by this coming Saturday or we will fail to do a schedule CES visit for the first time in 32 years!

Recaptures: (0) 

Sightings: 30+ Swallows all in one gathering flew North and a bit later 40+ House Martins drifted South. We haven’t had a Bullfinch here for a while and the Starlings were flying Northwest in double figure groups. We don’t often see Rabbit here, they tend to remain in cover to avoid dogs etc. Noted the Black Ants because I have not seen any ants recently, these I saw running up and down a fence post looking for food. 

As for recent visit fewer birds about generally.