Fieldwork August 2022

Avian Influenza (AI) precautions: With the spread of AI to wild birds (mainly colony nesters), we followed BTO guidelines and also introduced extra safety precautions to minimise risk – see here. There were also some sites we did not have access to for catching.

Friday 12 August

Recces were carried out early on Friday morning:

Norfolk: Cathy found Heacham Beach, north of the Ringed Plover fencing, was gull city with no waders present. Heacham North North at high tide had 33 Turnstone and 26 Ringed Plover.

At Terrington Marsh Carole and Bernard found the White Barn and E Pools were dry. The cannon-nettting pool had only a trickle of water after tide and 28 cows around the area. There were no waders on the salt marsh until a flock of Grey Plover circled round at 06:40 landing near the tide line. Some ten minutes later 120 Curlew arrived and settled on the marsh in a tight line. These were disturbed by a dog walker at 08:00 and flew off west.

Royal Estate: Permission was confirmed for this location.

Lincolnshire: Saltmarsh near the Horseshoe Lagoon: Steve had identified a possible Curlew catch available for Saturday morning which was unlikely to recur during the forthcoming tides. Catching Curlew on the Lincolnshire side of the Wash to put GPS/GSM tags on them is a priority this autumn. We have been following colour-marked Curlew for several years and found that some of them feed inland (see here). To extend this work (and find out more about their annual movements), we tagged 10 on the Norfolk side, which are giving great results showing us feeding locations we didn’t know about, exactly where each bird breeds and the migration routes they take. We now want to look at the Curlew on the Lincolnshire side of The Wash to find out if they also use fields extensively – we have 10 tags to put on.

Holbeach Greenshank pool: Richard arrived over two hours before tide and met Martin the farm manager. Permission was confirmed to catch at this site and the first two Greenshank arrived 90 minutes before tide, both were unringed.

Gedney Pool: Lizzie and Tim had 100 Grey Plover and 20 Curlew on the pool.

A team assembled in Lincolnshire at 16:00 to set one net in preparation for catching Curlew in the morning. The available team fluctuated somewhat as work and vehicle issues changed the original plans, however the set was completed and these team members joined those already assembled at the Norfolk base. A meal of baked potatoes and additions was prepared by Kirsty and Selena followed by team introductions.

We welcomed Kirsty as a newly registered cannon-net trainee, joining Lizzie, Ryan and Guy who are already training. We were also joined by Anna and Christina from Christ’s College Cambridge (‘Team Poop’). Anna is starting a genetics study on pathogens carried by waders (including everything from viral to bacterial to parasitic), using full spectrum genomic sequencing of individual bird ‘pathobiomes’ from faecal samples. Avian Influenza will be just one of the pathogens she will be looking at and she is also interested to see if there is a cumulative pathogen impact in individuals (so for example, if a bird is infected with one thing, then does that make it more susceptible to another), and then linking that to individual or population-level outcomes (e.g. survival). As this was the first time we had collected faecal samples on The Wash, the process was refined after each catch as methods were tried. Further refinements, mainly regarding the containment of the birds, will be made for the next trip in September.

Saturday 13 August

The majority of the team drove to Lincolnshire, leaving at 04:30 (setting) and 06:15 (Base camp). The base camp team were under camouflage on the saltmarsh close to the net and the firing team of four were in large, pop-up hide on the sea wall. Decoys were put out (when there was zero wind), and a remote tape lure was used. Most Curlew on the saltmarsh in the area had flown north. At one point there were up to 18 birds in the catch area but, with one in safety, we couldn’t catch them. Following this there was a split-second opportunity to take a catch, but radio communication was unable to confirm the arming of the box before the birds lifted. Up to 12 birds then reassembled but as the decoys were not quite facing into the light breeze that had got up, they weren’t helping. We eventually caught seven Curlew, all of which were flagged and GPS/GSM tagged. Two faecal samples were collected.

Photo of a table full of GPS-GSM tags set up ready to be put on Curlew. by Cathy Ryden
GPS-GSM tags set up ready to be put on Curlew, by Sam Franks
Bar-tailed Godwit1 1


Bennington: Rob P and Barrie had 35 Curlew in a stubble field (TF 422455) northeast of the RSPB reserve at Frieston. Steve was summoned to assess the site after the morning catch and it was deemed suitable to use later in the week.

Terrington Marsh: Richard had ~1,000 Golden Plover in the only cut field available. 200 Curlew (including a head-started bird) looked at a field near the inner bund and then settled west of the white barn. The cannon-netting pool had two deer plus a small amount of water.

Wolferton Pool: Kirsty and Tim noted the pool was dry but there were 500 Curlew just beyond an hour before high tide. The only birds in fields were geese and 250 Ringed Plovers and 50 Dunlin in a dry pool closer to the pumping station embayment.

Some of the team in Lincolnshire set the seven-cannon net on the Horseshoe lagoon, along the edge of the tall grass. This is a large mesh net which has been adapted to be fired with seven cannons and extended jump ropes to allow for it to travel further with the intention of reaching birds beyond the 12 metres of a regular set. The anticipated species were predominately Oystercatchers, Knot and Bar-tailed Godwit.

The remaining team members returned to the Norfolk base and made breakfast for the entire team, masterminded by Kirsty.

A team (27 in total) then left at 15:00 to set a full, small-mesh net on the saltmarsh at Gedney in preparation for a catch that evening. A picnic dinner was provided by Anna, Katharine and Chantal and enjoyed on the seawall. The team aimed to be in position by 18:15 with most members hiding under camouflage on the marsh with Richard and Lizzie watching the net from the seawall. At one-point things looked promising with nearly 20 Black-tailed Godwit catchable and birds coming onto the lagoon. However, these were flushed by a Peregrine and the only birds which subsequently returned to the catch area, were gulls. It was agreed the catch failed and at approximately 19:30 the net was lifted with everyone returning to the Norfolk base.

Sunday 14 August

The seven-cannon net on the Horseshoe lagoon was the venue for our next attempt with the hide team (Nigel, Steve, Kirsty, Louis) in position by 06:30. Base camp (20+ people) parked at the camp site and walked around the seawall to be in the firing position by 07:30. Steve’s truck was driven by Molly to bring boxes to the site in the event of a catch and Saskia was driving Richard’s car. An additional two cars (three people) arrived in time for the lift.

Numbers of Dunlin gradually increased to around 1,500 with 300 Oystercatchers and 50 Redshank and 1,000 Knot well out of the reach of the net. We waited for water to come into the lagoon and hoped the birds would be pushed towards the net. A Peregrine flew over from the NE at which point all the birds lifted. The Knot and Bar-tailed Godwit departed with Dunlin staying in the area. A microlight passed over which didn’t disturb the birds, but this was followed by a bright-red aeroplane which disturbed all the birds again. Some birds returned but were further out than we hoped. Many team members were involved in a debate about whether to go for a small catch today or wait and try again another day. It was concluded that it was advantageous to test the net and see how far it did go in the hope of getting at least a sample of 100 Oystercatchers. After firing it became clear to the team that the net had gone out very well and a large flock was lifted 20 metres clear of the lagoon by the entire team (29 people). All birds were extracted and taken to keeping cages on the shorter grass. As it was unusually hot, shade was erected over the keeping cages and faecal samples, ringing and processing was carried out by all team members. In addition, two ‘recycled’ GPS/GSM tags were deployed on re-trapped Oystercatchers which will likely stay around this area and give us more insight into the habits of birds on the Lincolnshire side of The Wash.

Hand gel was used between handling batches of birds and between species. All equipment was sprayed down after use to comply with our recent HPN1 protocol to limit the possibility of spreading Avian Influenza should it be found in wader flocks. In total 75 faecal samples were collected from 45 birds, some in bags and some from keeping cages or clothing wherever the birds happen to perform and provide enough of a sample!

Dunlin56 56
Turnstone1 1
Photo showing keeping cages under shade cloth at the Horseshoe Lagoon, by Cathy Ryden
Keeping cages under shade cloth at the Horseshoe Lagoon, by Cathy Ryden

The team then split in to three, with one team staying at the Horseshoe Lagoon to build a wall of mud turfs, another to set a net on a stubble field and another to shop and cook breakfast. The wall team were preparing a platform for a half net to be set the following day in the hope of catching some Knot for ringing and flagging and Dunlin for ringing. Guy was operating a vintage 1970’s spade to remove the turves and managed to snap the blade with a loud bang as it broke. We continued to use it as we only had two spades and some way to go!

The stubble field was chosen for Curlew as identified earlier in the trip. A single net was set with the greatest problem being the digging of holes for the cannons as the ground was rock hard. A mallet was used to strike the spade and loosen up the soil. An area in front of the net was strimmed to provide an inviting patch for the birds to choose to land in. Decoys would also be placed here in the morning.

Two teams went shopping to get breakfast and a meal for later (left – one of the trollies). Then we all returned to the Norfolk base where Lizzie and team cooked a hearty breakfast rather later than usual. It was 17:20 before we had all finished! There were no resighting options as we would need to be on the beach at Snettisham by 18:00 to see birds on the rising tide and no-one was going to make it! As planned, we had the night off, as the tide was too close to last light for mist-netting and too late in the day for cannon-netting. A curfew was arranged so social activities stopped at 22:00 to allow the team to rest before the busy days ahead.

Monday 15 August

Most team members were deployed to the Horseshoe Lagoon, with the intention of assisting at the Curlew field (see below) if we failed to catch. Three groups left at half-hourly intervals with the hide team (Nigel, Steve, Elli, Ruth) leaving at 04:45, a base camp team (8) to go under cover at 05:15 and (11) in cars behind the sea wall at 05:45. There was more water in the lagoon than anticipated and birds were gathering behind the net, the Knot were absent having been flushed by a Peregrine the previous day. About 800 Dunlin were on the pool and 70–80 Oystercatchers. If the net had been set to fire in the opposite direction 100–250 birds would have been catchable. However, everything was lifted by yet another visit from a Peregrine which took an Oystercatcher (later identified as one we had ringed the day before). The decision was made to swiftly turn the net round in the hope of giving another chance if some birds came back. 100 Redshank landed 20 yards from this new net position but the team under a non-breathable tarp begged for release from the sweatbox once high tide had passed.

The Bennington field car hide team (Richard, Katharine, Barrie) left at 05:45 and a car and walking twinkling team (Kirsty, Sam, Jacquie) left at 06:50. There was no wind when the decoys were placed in the strimmed area. Birds land and generally roost facing in to wind so would not be impressed to see dummies facing the wrong way! One Curlew came to join the decoys but 130 Curlew landed in a young cabbage field to the north. There were flocks of Golden Plovers and gulls around and more Curlew joined those in our field and other fields. Kirsty was sent to twinkle and left in a field to prevent the birds returning. Jacquie and Sam were directed to retrieve Kirsty and position themselves at the corner of the catch field. By this time the Lagoon team had given up and team members in cars were sent to the Curlew field to assist with twinkling there. Wayne was directed to go along the seaward edge of the field to lift the Curlew and Whimbrel in the hope that they would come closer to the decoys. By now the wind was proving the decoys were not helping by facing the wrong way and a Peregrine passed over disturbing the birds. Several times there was an option to take a small catch but by waiting a few seconds more for birds to land in the catch area, they thwarted our efforts by choosing to fly over and lift what we already had. This was rather frustrating, so on the next option, Richard took the catch – which proved to be smaller than hoped, but did include Whimbrel. The Curlew was a juvenile, which is rare for us to catch, and it joined the cohort of tagged birds from Lincolnshire this summer. It will be interesting to see how it behaves relative to juvenile head-started birds which have been released in Norfolk over the last two summers. Both Whimbrel were carrying a lot of fat as stop-overs in the UK are short and often not needed. Both were therefore ringed, measured and released as quickly as possible. Some faecal samples were collected, with the Curlew donating generously.

Curlew1 1
Whimbrel2 2
Total3 3
A group of ringers standing in a stubble field in the sun, listening to a briefing from the team leader, by Cathy Ryden
Steve briefing the team, by Guy Anderson

After a short break to discuss plans, the Lincolnshire team stayed on the west of The Wash with the Norfolk team returning to base. Both teams planned to mist net in the evening.

The Lincolnshire team spent some time seeking out Little Grebes and were successful in catching one, with the unfortunate twinkler getting very wet in the process. A fact known as being likely by those in charge, but not the unsuspecting victims. After taking refuge during a rain storm 13 mist nets were set and a successful evening resulted in 46 birds being caught with Redshank and Bar-tailed Godwit being the most numerous. The Knot was flagged. The team then returned to Norfolk setting off at 00:50 and arriving just after the last of the Norfolk team had retired.

Knot1 1
Bar-tailed Godwit15318
Redshank16 16
Total     41445

Plus a Little Grebe

Meanwhile the Norfolk team had left to set 17 nets at 17:30 with supper planned for 19:00. This became a moveable feast of curry as setting was slower than expected and a flat battery added to the time taken. Louis opted to stay down on the marsh to be a presence should there be any visitors and a meal was taken to him by the first returning group members. Tape lures were put out at the two net lines and teams stood back as tide approached. The window for catching was quite small as the light only faded rather close to high tide. Birds were separated at the nets for faecal sampling and brought back to the White Barn after the second net round. The white barn pool had a visit from some enthusiastic cows which created a bit of a stir. Calm was restored once all members were back at the barn. The Knot was flagged.

Knot1 1
Dunlin1 1
Redshank23 23
Total25 25
(plus a Little Grebe)

Tuesday 16 August

Resighting options for the morning were for around 06:30 on the rising tide, 10:00 for high tide or between 12:00 and 13:00 on the falling tide.


Frieston: Ryan and Richard left at 08:30 and had 20 WWRG Redshank, one Humber, one Welsh, one Scottish and one Lofoten Oystercatcher. Stopping at Lidl in Boston they noted a fine is imposed of £90 if you omit to enter your registration on a terminal in the store. Take note for future reference.

Frampton: Barrie and Wayne had six Godwit


Wolferton: Carole and Bernard in a pop-up hide had 58 birds and were lucky enough to encounter a Wasp Spider.

Snettisham pits and beach: Anna, Flo, Elli, Guy and Christina left at 07:30 and had a handful of Black-tailed Godwit and some Little Tern colour ring resights. On the falling tide there were two marked Curlew seen and one combination read. It seems the birds are not coming close, perhaps because there is plenty of food available at this time of year and as food stocks diminish over the winter, they may come closer.

Ken Hill: Rob Rob Nothing to report.

Heacham North North: Saskia and Cathy left at 10:25 and had one Turnstone.

Hunstanton: Saskia and Cathy walked on from HNN and among a flock of 164 Turnstone had 1¾ birds (one has lost a colour ring).

Richard and Kirsty took the next step in sorting out a fibre broadband line to the house. Cartridges were loaded and an inventory of cartridge stocks updated, any used cannons were greased ready for the next trip and the washing up was cleared.

The later plans were to meet at 15:45 for a briefing followed by a meal of sausage hot pot as prepared by Lizzie before heading out to mist net, with one team going to Gedney and the other to the Lincolnshire shore. Weather forecasts were consulted and although some rain was expected it seemed most heavy clouds would clear in time.

Nets were set and a later crew from the Norfolk base set off minutes before a message was relayed to say the catching attempt was off due to the rain and the team were taking down the nets. Jacquie, Flo and Cathy arrived without this knowledge only to be told the news as they arrived – and drove straight back. The rest of the team were soaked as they took down the nets and retreated to the cars in heavy rain.

No news had reached us from the Lincolnshire team until pictures of Rob’s car at an ungainly angle astride a mound appeared on the WhatsApp group. Steve was requested to return to the site and pull Rob’s car out of a ditch and everyone returned to a big social gathering at the Norfolk base. During this time Max sat quietly drawing and shared the results with the team. ‘Guy eating crisps with Richard consulting and sharing weather forecasts’ and ‘Rob’s car on the edge of the ditch’.

Overnight there was extensive rain especially around 05:30. Those of us in tents were lucky to stay dry and unfortunately those leaving early had the task of taking their tents down in the rain. Yuk!

Once the team had breakfasted, plans for a big tidy up in the garage and office were made and everyone found themselves busy. Gradually team members departed as the clearing up was achieved. Unfortunately for Tim his departure through the gates of the base was not without incident as the caravan clipped the metal gate post. All muscles were required to push the caravan away from the post so no further damage was caused.

During the trip some Headstarted Curlew were released at Ken Hill and another cohort tagged ready for release the following week. Sam and Katharine were joined by Tim, Carole and Bernard.

Re-sighting (Carole)

This trip provided some excellent resighting opportunities with two members of the team focussing on resighting at Snettisham on the Norfolk side of The Wash and others at Freiston and Frampton in Lincolnshire. Resightings of Curlew and Bar-tailed Godwit were mainly from Wolferton, courtesy of permission, from the Royal Estate, allowing us to access the high tide roost areas which are not visible from Snettisham Pits. This was especially useful given that these two species were not using the beaches to any extent on either incoming or outgoing tides. Four of the non-WWRG Curlew were yellow-flagged birds from the 2021 Headstarting project.

There were substantial numbers of resightings of three other species as follows:


We have been colour-marking Redshank at RSPB Freiston since 2019 and it was fantastic to get so many resightings of this species from this site during the trip. These birds seem to be incredibly site faithful with no sightings, as yet, from other sites on The Wash. The objective for this project is to monitor survival of Redshank on The Wash as we do not recapture enough metal-ringed birds to be able to get precise survival estimates. These sightings will contribute towards this analysis.


Good numbers of Knot were roosting on the island closest to Shore Hide which enabled a total of 22 flag readings. These were mainly birds with orange-flags of which 10 were ringed on Merseyside and four in Scotland. Whilst some of these birds were only ringed earlier this year, others have rich histories demonstrating the movements of Knot between The Wash and Merseyside.

There were many thousand more Knot roosting on the islands further away from the hides for which there is no suitable access for flag reading. Unfortunately, none of the WWRG-ringed Knot with lime-flags were encountered during the trip which was disappointing.

Black-tailed Godwit

There were ~2,000 Black-tailed Godwit roosting on the pits at high-tide which enabled good numbers of readings. In addition, there were also good numbers roosting at Frampton. These are mainly birds that are moulting on the Wash which will soon leave for their wintering grounds. There was a good mix of birds, ringed in Iceland, Portugal, France and the UK, many of which have very rich histories.


All three individuals were ringed earlier this year by the Mid-Wales Ringing Group at Ynyslas Nature Reserve in Ceredigion Bay.

Resighting totals

Bar-tailed Godwit29281
Black-tailed Godwit45045
Grey Plover110

This was the first full trip since the pandemic where we were fortunate to meet as a large team without restrictions. All members were requested to test for Coronavirus prior to the trip and the week went off without a hitch in this regard.

There were several vehicular issues, notably one broken fan belt, one flat battery, an unfortunate dip into a ditch and a close shave with a caravan. All relatively minor in the grand scheme of things.

Thank you to everyone for making this such a successful and memorable trip. With people pitching in to help with meal preparations, washing up, sorting equipment etc. – team WWRG Aug 2022 well done.

Ringing totals

Time (of cannon net catch)07:5009:2009:45
Newly Ringed
Bar-tailed Godwit11516
Total newly ringed628232541357
Bar-tailed Godwit33
Total retraps/ controls22000426
Wader catch total830232545383
(Plus one Little Grebe in Lincolnshire)

Thanks to Cathy Ryden for writing this report.