Monday 11 June 2012

Ringing with the Delaware Shorebird Project, May 2012

Just over four years ago, I ringed my first bird. Back then, I never dreamt that ringing would take me to so many wonderful places around the UK, let alone that it would lead me to America. I would probably have laughed if anyone had suggested that in four years’ time I would be sitting here writing a blog post about having had the privilege of spending two weeks ringing waders (banding shorebirds) with the Delaware Shorebird Project (DSP) in Delaware Bay.

On May 19th, I travelled down to Heathrow to take my first trans-Atlantic (and first ever long-haul) flight out to Philadelphia. At this point, I feel I must pay tribute to Lucy, Rob and Sarah for putting up with my ‘kid on Christmas morning’ excitement and sheer naivety about all things airport / flight related…sorry guys!!! Anyway, we made it safely onto the plane only to sit in a queue on the tarmac for quite some time. We never did find out what the hold-up was, but at least it made a pleasant change from sitting in a queue on a motorway! And, as we waited for our turn to take off, we had the opportunity to ogle the bright yellow BA plane that the Olympic flame had travelled to England in the day before. There really was no missing its yellowness – or should that be goldness!

The flight over to America was pretty uneventful, except for the turbulence, Rob dancing in his seat to the Muppets movie (complete with hand signals and sound effects) and the hysterically rude air stewardess (or whatever PC term we are supposed to use these days) who advised me that ‘of course you can’t be vegetarian AND gluten intolerant, that’s just impossible’! I am not afraid to admit that she reduced me to tears … of laughter!

As we were coming into land, Sarah instigated a game of ‘try and spot your first American bird before we land’. I failed miserably (my excuse is that I didn’t have a window seat and leaning over someone is just rude). As we were taxiing I did manage to start my US list, however, it wasn’t quite what I was expecting … European starling! This was swiftly followed by red-winged blackbird and common grackle (yey, American birds) then feral pigeon and house sparrow (hmmm!).


Red-winged blackbird (male)

We were met at the airport by Greg, one of the Americans working on the DSP, in his people carrier and we were soon speeding our way to Slaughter Beach, our home for the next two weeks (the name is derived from the original Dutch name, not anything more sinister). My bird list started to grow on route with fabulous views of turkey vulture (the American equivalent of our buzzard) and osprey (which are ridiculously common over there).

Turkey vulture

Osprey taking food back to the female on the nest

On arrival at Slaughter Beach, we took a quick detour to the Dupont Nature Centre, to allow the newbies (Lucy and me) our first view of Misspilion Harbour. No sooner had we stepped out of the car than we were greeted by Kevin Kalasz (Wildlife Biologist with the US Fish and Wildlife Division and Delaware Shorebird Project leader) and other members of the Wash Wader Ringing Group (WWRG) who were there helping out with a public event. Our arrival took the total number of WWRG members working with the project to ten (six members had already been out there for a week when we arrived). The evening was spent settling in and meeting the rest of the team before the fun, I mean hard work, started the next day.

Delaware Bay is positioned on the Atlantic Flyway and is the final staging area for thousands of shorebirds on their migration from their South American / South-eastern US wintering grounds to their Arctic breeding grounds. In spring, the Bay is also home to horseshoe crabs. These prehistoric looking creatures spawn on the beaches in their millions and their tiny green eggs are full of protein – just what the hungry shorebirds need to replenish their body fat and to provide them with enough energy to complete their journey north. In the short time that the knot spend in Delaware Bay (1-2 weeks) they can double their body weight by foraging on crab eggs!

Horseshoe crabs - the smaller one is the male which is hanging
on to the larger female using adapted front claws
Unfortunately, for a number of complex reasons, the shorebird populations have diminished in recent years. In 1997, the Delaware Shorebird Project was established to research and monitor the health of the shorebird populations in order to better understand the connection between the birds, Delaware Bay and the horseshoe crabs. The data gathered is helping to identify and protect the resources that are so critical to the success of the shorebird migration. The DSP works in partnership with the BTO and the Wash Wader Ringing Group and it is through the latter that I was able to join the project this year. A sister project, the Delaware Bay Shorebird Project (led by Clive Minton), runs concurrently on the New Jersey side of Delaware Bay. The birds use both sides of the Bay to feed, often swapping shores to avoid inclement weather. Having data from both sides is crucial for researchers to gain a full picture of the state of the shorebird populations using Delaware Bay.

Project work involves catching and flagging birds, counting the numbers of birds using each of the beaches each day and re-sighting the colour flagged birds. The aim of the project is for the two teams to each catch 350 individuals of each target species each year; target species are red knot, ruddy turnstone, sanderling (all of which are colour flagged) and semipalmated sandpiper (not flagged on the Delaware side). Approximately every three days, attempts are made to catch ‘samples’ of 50 birds of each species. Samples of dunlin and short-billed dowitcher are also taken if caught and occasionally, other birds including semipalmated plover and least sandpiper will also find their way into a catch and are ringed.

It wasn't always easy to count the birds!
When not catching, time is spent counting the birds in the Bay and attempting to find and read leg flags using telescopes. Team members visit the key beaches along the Bay shore, including Back Beach in Misspilion Harbour, where the largest numbers of birds congregate. Re-sighting colour flagged birds gives information on arrival and leaving dates of individual birds, movements of individual birds within the Bay and information on survival of individual birds.

Approximately 10% of the red knot population passing through the Bay is estimated to be flagged, along with smaller percentages of turnstone, sanderling and semipalmated sandpipers. Flagging projects are undertaken in a number of different countries; the flag colour indicates which country the bird was flagged in. In the US, lime coloured flags are used, Canada uses white, Argentina orange, Brazil blue and Chile red. Percentage counts are also taken of knot and turnstone to ascertain how many birds in the group are flagged e.g. 50 clearly visible birds of one species will be counted and the number of flags noted. Researches can then use this data to extrapolate the percentage of the population that is flagged.

Red knot sporting Flag Orange EPX indicating it was ringed
in Argentina
The above, in a snapshot, is what I spent my two weeks in America doing. It all started on the Sunday morning with an early morning boat trip out to Back Beach. When the other team members suggested that the four new Brits should do the early boat trip as our body clocks would be out of sync with US time and we would therefore be awake at silly o’clock, I was a little sceptical. But, right on cue at 4am, I found myself wide awake and raring to go! The birds had arrived on mass a few days previously and the numbers in Misspilion Harbour that morning were truly astounding. I had been told that colour ring re-sighting would be a little different and a little easier than in the UK but I was not prepared for just how close the birds were prepared to tolerate us. Once in position, the birds were happy to come within just a few feet of us which would have made re-sighting very easy if it weren’t for the ‘peep’ pollution getting in the way (the thousands of semipalmated sandpipers running around and obscuring the flags on the legs of the knot, turnstone and sanderling)!

The morning took an unexpected twist when I spotted a gull that I couldn’t identify loitering on the beach amongst the laughing gulls. Assuming it to be a common American species that I was unfamiliar with, I asked Kevin what it was. Also unable to identify it, he asked a similarly confused Sarah and then phoned a friend – who identified it from the description as a Sabine’s gull and instructed us to keep an eye on it as he was on his way and would be there in an hour! It turned out to be only the third record for the state of Delaware and only the second mainland record as one of the previous two had been pelagic.  The bird proceeded to hang around the harbour for a week and proved quite popular with the ensuing twitchers!


Sabine's gull
That afternoon, I had my first chance to ring (band) birds the American way. Nigel and co. had been playing with the walk-in traps on Slaughter Beach and had managed to catch 64 semipalmated sandpipers, 3 short-billed dowitchers and 1 semipalmated plover. I have no idea why I assumed that ringing in the US would be the same as here but I was wrong, however, it didn’t take too long to get to grips with the slightly different ring sizes, ring materials and processing codes. I was lucky enough to be able to ring half the semis and one of the dowitchers, whilst Richard ringed the plover. Two new species ringed on my first full day there was a nice start to the trip.

Short-billed dowitcher being released
Overnight, the weather turned a bit tasty and the planned early morning cannon net catch was postponed so instead, Monday saw me team up with Lucy and Jacquie for a recce and re-sighting trip up to Port Mahon followed by a sneaky birding trip up to Bombay Hook national wildlife refuge (nature reserve) to enable me to buy an American bird guide. It was at this point that I concluded that American birds all seemed to be bright and colourful and remarkably easy to see. My bird list was growing rapidly! Later that day saw the first cannon net attempt of my trip, with turnstone the target at Port Mahon. A successful catch saw us processing 53 turnstone, 2 sanderling, 1 knot and 2 short-billed dowitcher.  All but the dowitchers went home sporting shiny new flags.

On Tuesday, we decided to go for a cannon net catch on Osprey Beach (named after the ospreys breeding on the platform – told you they were everywhere!). The setting team headed out in the boat, whilst the rest of us walked along the beach to base camp, flipping the horseshoe crabs that were stranded on their backs as we went. The beach was full of birds but they weren’t quite where they needed to be so I was asked to gently twinkle them into the catching area. I have to admit to feeling slightly guilty as I crawled past the osprey platform and disturbed the female off her (presumed) eggs!!! Note next difference to twinkling in the UK – warm dry sand is far nicer to crawl on hands and knees along than freezing wet sand! The birds soon found their way into the catching area and we took a catch of 90 knot, 20 turnstone, 3 sanderling, 83 semis, 86 short-billed dowitcher and 40 dunlin.

The catch took an interesting twist whilst processing the dunlin. I was ringing the birds and passing them directly to Jacquie as the lead processor on the team and all was well until Jacquie turned a bird over to do a plumage score on it and exclaimed “what the hell is this?” An initial look determined that this was no ordinary dunlin! On closer inspection (and having called the resident dunlin expert, Nigel, back to the beach) it was concluded that the bird was a hybrid dunlin x white-rumped sandpiper! Lots of photos were taken and a couple of feathers were bagged for DNA analysis to confirm its ID – it will be very interesting to hear the results.

Hybrid dunlin x white-rumped sandpiper

Hybrid dunlin on left, 'normal' dunlin on right

Hybrid dunlin above, 'normal' dunlin below
That afternoon, whilst re-sighting turnstone at Port Mahon, I had my first sight of a bald eagle – a full grown adult being mobbed by an osprey! Not a bad first sighting. On the way home, Rob and I snuck in a short birding trip to the Little Creek reserve were I was lucky enough to see a red-tailed hawk and a pair of cedar waxwings.

Wednesday saw us spending the day re-sighting in very foggy and humid conditions whilst on Thursday I was introduced to the concept of the aerial survey. Ground counts are taken of the birds on key beaches every 15 minutes for an hour before the survey plane arrives. The plane then flies low over the area and deliberately flushes the birds to enable the counters on board to estimate numbers from the air. All very spectacular!

 
Survey plane flushing birds from Ted Harvey Beach

On Friday, we attempted a cannon net catch on Back Beach. The high winds earlier in the week had caused a lot of the knot to head over to the more sheltered New Jersey side of the Bay and many of the remaining birds had moved to the more northerly beaches. When the Sabine’s gull had decided to stop sitting on top of the net, we took a catch of knot, sanderling, dunlin, semis and dowitchers and boated them back to the shade of the nature centre to process. Another catch of 18 turnstone, taken later that afternoon on Slaughter Beach, helped to make the numbers up for that species for the day.

Semipalmated sandpiper ready to go
 
Sanderling ready to go
 
Semi heading home

Before I knew it, I had been there for a week and it was nearly time for four of the other Brits to head home. Not wanting to let them have too easy a time of it on their last morning, we went up to Ted Harvey Beach for a cannon net catch. After a lot of twinkling and gentle persuasion, the birds cooperated and we took a nice catch of 50 turnstone, 64 knot, 2 semis and 1 dowitcher. Our findings from earlier in the week were confirmed here, namely that the knot were really, really fat! The target weight for a knot to reach before it leaves Delaware Bay is 180g. Out of the 64 caught, 35 were above this weight, with the heaviest being 208g! The turnstone were similarly rotund, with the heaviest being somewhere around the 175g mark! An evening boat trip to Back Beach found few knot left; most of the re-sightings we were getting were now of turnstone and sanderling.


Members of the Wash Wader Ringing Team after the morning's
catch and before Nigel, Jacquie, Dave and Liz headed home

Sunday was another aerial survey day but the counts were slightly complicated by the fact that it was Memorial Day weekend and the beaches were very busy with people! That evening and Monday morning involved re-sighting trips to Back Beach, with the number of birds present diminishing with every visit. On Tuesday, Slaughter Beach was full of semis so we attempted to catch them using walk-in traps. When it became clear that this wasn’t working, the whoosh net came out and after only two firing attempts, we had just over 200 birds in keeping cages. This gave me a great opportunity to practice measuring heads and bills on a small species.


The semis did not want to play with the walk-in traps...

...so we resorted to the whoosh net!
That afternoon we attended the official launch event for the Delaware Bayshore Initiative (if anyone is interested, details can be found here: http://www.dnrec.delaware.gov/Pages/Delaware-Bayshore.aspx) which was attended by the great and good of local politicians as well as the US Secretary of the Interior, Ken Salazar. As an equivalent of a British Cabinet Minister, he was accompanied by an extremely unsubtle security detail, which amused some of the Brits greatly!

By now, most of the knot had headed off for colder climes and the remaining species were beginning to follow them. As the birds cleared out, the project started to slow down and the remainder of the time was spent on obtaining as many flag re-sightings as possible. This also meant that there was some free time for birding, which included taking a couple of short trips down to the beautiful Prime Hook National Wildlife Refuge.

On Friday, Kevin took those of us who wanted to go out for a fantastic day’s birding down to Redden State Forest and to Cape Henelope. Before setting out he asked me (as the only person never to have visited the States before) what I would like to see. I proceeded to give him a ridiculously ambitious list knowing I would be happy to see only half of what was on there. Well, I wish I had asked him for the lottery numbers because he delivered every single bird on the list including blue jay (ridiculously common over there but I hadn’t seen one), red-headed woodpecker, pileated woodpecker, scarlet tanager, brown-headed nuthatch and the pièce-de-résistance, piping plover! It was a fabulous day out to end a wonderful two weeks (and it took my bird list total to 112 species).

The piping plover is a threatened species in the US due to habitat
loss, disturbance and predation 
Provisional figures put the total number of birds ringed in 2012 at 1139. Nearly 16 000 colour ring re-sightings were recorded from 3561 individual birds. Not bad for three weeks!

I would like to take this opportunity to thank Kevin and Nigel for giving me the opportunity to join the project team and to thank everyone involved in the trip for making it a fabulous and rewarding experience. It was a real privilege to be involved in the project and to work with such a dedicated and knowledgeable team.

The team, as of the middle Saturday of the trip


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