Delaware Bay Shorebird Project 2015 Archives - Conserve Wildlife Foundation of NJ

Banding Together: When the Shorebird Met the Biologist

Posted on September 6, 2015 by CWF

Celebrating World Shorebirds Day, Sunday, September 6

by Lindsay McNamara, Communications Manager

As a bird nerd, I’d often look on enviously at photos of biologists posted online holding shorebirds in their “bander’s grip” – the bird’s head in between their index and middle finger, using their thumb and pinky to steady the bird, while allowing its feet to dangle freely.

I always wondered: I wish I could do that! Hold a bird in my hands. Yet I never once thought: Wait, how did the bird end up in their hands in the first place?

I certainly hadn’t thought biologists run all over the beach chasing after shorebirds like a farmer chasing chickens – I just never thought the process all the way through.

This past summer, I was fortunate enough to become part of that process and learned exactly how a shorebird ends up in a biologist’s bander’s grip. The system may surprise you, but the steps have been mastered over nineteen years of practice, each one with shorebird safety as the top priority.

Conserve Wildlife Foundation (CWF)’s Delaware Bay Shorebird Project celebrated its 19th year this summer. The team members, led by Drs. Larry Niles of CWF working with Amanda Dey of New Jersey Division of Fish and Wildlife, are all extremely passionate about what they do and care deeply for the shorebirds they are studying and protecting.

I arrived at the team’s house on Reeds Beach, along the Delaware Bayshore, early in the morning. Dr. Niles was concerned about the wind and had scoped out the safest beach for the banding that day. Our group of scientists, volunteers, supporters, interns and staff caravanned to Villas and joined our partner, American Littoral Society, at the site. We all picked up large, colorful plastic tubs, which had cloth covers that fit securely over the top of the box. The cloth cover had a Velcro pocket. We were told that these boxes would help in the shorebird “catch” that day. Larry and Mandy gave us instructions for how the banding day would go, safety tips and background information on the Delaware Bay Shorebird Project. We all listened intently and couldn’t wait for the day to begin!

The team waiting with our bins. Photo by Lindsay McNamara.

Well, we waited a bit before the day truly started. Dr. Niles and his team had binoculars with them and sat down in the sand, watching the shorebirds from afar for about an hour and a half. We waited by the cars up near the houses along the beach. The reason for the long wait? Dr. Niles and his team were waiting for the perfect moment to fire the net over top of the shorebirds along the coastline.

Biologists rolling away the net to reveal more shorebirds. Photo by Lindsay McNamara.

Cannons with gun powder charges fire heavy projectiles that carry the net over the birds only at the perfect moment – when birds are catchable and none in danger. Luckily, it was not a “wet catch,” that day, as the net did not go into the water. As soon as the cannon was shot, we all spirited single file carrying our tubs down the beach, following the biologists. The biologists immediately knelt at the base of the net and started picking up birds and shouting their identification and passing them to us, as they went they rolled the net away to reveal more birds.

It was very exciting! The idea was to get the birds out from under the net and into our carrying boxes and sealed in with a Velcro flap, as fast as possible, for the safety of everyone involved.

Each bin became devoted to the same bird species, so if the first bird that was handed to us was a sanderling, we kept putting only sanderlings in our bin. Once we had several birds in our bin, our pace completely changed. We walked very slowly away from the net, keeping the bin level at all times, towards the path in the sand at the beginning of the beach, to make the journey as safe for the birds as possible. There, biologists had burlap “keeping cages” for the birds to wait in. Birds were also sorted by species into these cages.

When every bird was taken out from under the net, and sitting in their temporary burlap enclosure, we formed “circles.” Each circle was composed of about 6 volunteers led by a core banding team member. Once formed birds were handed to us and finally, I learned how to safely hold a shorebird in my very own bander’s grip!

My very own bander's grip! Lindsay McNamara holding a sanderling. — My very own bander’s grip! Lindsay McNamara holding a sanderling.

Each bird received a metal band with a federal identification number, and a green tag with a three letter code. One person in the circle put the band on the bird and passed the bird to the next person, who placed the green tag on each birds’ leg and glued them shut. A recorder took notes on the band number and tag letters. Next, the birds’ wingspan and other data points were measured by other members in the circle. Lastly, the bird was weighed before it was released. During my trip with the banding team, we caught a large number of sanderlings and a few ruddy turnstones, federally listed red knots, and semipalmated plovers.

Banding team supplies. Photo by Lindsay McNamara.

Holding a shorebird in my bander’s grip was an amazing experience, but what I enjoyed most of all was taking part in the science of shorebird conservation. I placed the green tags on the shorebirds, which will tell other scientists who may recapture the birds that they once traveled to New Jersey. Our circle helped collect valuable data points, which will be combined with the data from the other years of the Shorebird Project, to assess the health of shorebird populations.

I wasn’t just holding a bird, I was helping the bird have a brighter future – and that is the best feeling any bird nerd can have.

Today is World Shorebirds Day! You can help shorebirds have a brighter future today by participating in the Global Counting Day Program. Join the hundreds of participants at over 93 locations that will count shorebirds and share their sightings online. Register today!

Learn more:

Lindsay McNamara is the Communications Manager for Conserve Wildlife Foundation of New Jersey.

2015 Delaware Bay Shorebird Banding Season Comes to a Close

Posted on June 2, 2015 by CWF

Delaware Bay Shorebird Project Team Finishes 2015 Banding Season

By: Dr. Larry Niles, LJ Niles Associates LLC

All our efforts to help shorebirds on Delaware Bay this year couldn’t have been better rewarded – nearly every red knot left the bay in good condition and in one of the earliest departures in the 19 years of the Project. We counted just over 24,000 knots in our aerial count of the entire Bayshore on May 26th. Just two days later, most had left and we could find only a few hundred, feeding on eggs like human shoppers feed on bargains at a half-price sale. By May 31st, virtually all were gone, along with the ruddy turnstones, sanderlings and semipalmated sandpipers. The beaches had an odd, deserted feel after the frenzy of the preceding days.

Photo by Jan van der Kam from Life on Delaware Bay

A good thing for birds and all those who love birds. The end of the shorebird stopover season also means the end of our shorebird team – at least for another year. All through the week, we lost team members—the North Americans left by car, those from other continents by air. Those who stayed shifted from research to manual labor: cleaning and storing equipment, closing up the rental houses, and reconnecting lost items to their owners.

Will our project continue? Now in our 19th year of work on the bay, one must recognize the realities of time’s passage. Clive Minton just cleared 80, and the rest of the original team will soon follow. This author, who started at relatively young 44, is now pushing his mid-sixties. Death visited our team this year with the passing of Allan Baker. Surely the rest of us will start “falling off the perch” as Clive is fond of saying.

Allan Baker, the Senior Curator of Ornithology and Head of the Department of Natural History at Toronto’s Royal Ontario Museum suddenly and unexpectedly died in 2014. His career included many significant achievements including early work that helped build a scientific case that overharvested horseshoe crabs caused the decline of red knot numbers. Photo from Wader Study.

And yet, all committed to return for a 20^th year. I worry over the fundamentals: our funding remains uncertain, the listing of knots as Threatened in the U.S. creates new regulatory hurdles, and N.J. politics seem to get more fractious every minute. Will there be a 20^th year of this project?

The answer starts and ends with the willingness of our team to do it again. It starts there because good ideas and projects always seem to find support; I know we will find a way. It ends there because this team provides the best chance of a strong scientific underpinning for protection. Our team includes some of the most important shorebird scientists in the world. At our dinner soirees (generously provided by Jane Galetto’s Citizens United team), Ph.D.’s are as common as empty beer bottles. It’s no surprise that conversation drills deep into conservation biology, behavioral ecology, migration physiology, stopover ecology, virology and many other subjects of interest to all our team, both scientists, old and young, and lovers of good science.

In many ways, the lives of our team members revolve around birds. The Delaware Bay Shorebird Project provides us a meaningful excuse to pull together once more. Our team members love birds, and do everything they can to help them. It’s been that way for 19 years, and it is this commitment that has led to this year’s results.

p180 red knots — This graph plots the percentage of red knots caught between May 26th and May 28th that have achieved at least 180 grams against the year of the catch. The 2015 result is still an estimate.

For the first time in 19 years, red knots left in a condition similar to the lucky ones migrating through before the fishing industry decimated horseshoe crabs in 1997. After that year, the populations of knots, turnstones, semipalmated sandpipers, and sanderlings fell off a cliff. For the last four years, however, the terribly reduced populations of shorebirds have been in rough balance with equally reduced number of horseshoe crabs breeding on the Bay. Consequently, the percentage of knots reaching the threshold weight of 180 g has climbed. (Knots need at least this weight to reach the Arctic and breed successfully.) From a low of just 5% making weight in 2003, they’ve clawed their way upward 30% in 2010, 50% in 2013 and now this year’s 90%.

Fat knot on the scale by Philippe Sitters

One must be cautious about the interpretation of this number but the catch of red knots on which it was based were truly fat birds! One weighed 226 grams, nearly 100 grams higher than its fat free weight. Whatever the figure it was a good season for both birds and the people who love them.

Learn more:

Dr. Larry Niles has led efforts to protect red knots and horseshoe crabs for over 30 years.

Red Knots “Vote with their Wings”

Posted on May 29, 2015 by CWF

An Update from the 2015 Delaware Bay Shorebird Project Team

By: Dr. Larry Niles, LJ Niles Associates LLC

Clive Minton is fond of saying, “the knots vote with their wings” as a way of saying knots concentrate in the best places for knots. Of course it’s true, animals move to the habitats they find most suitable, nature leaves little room for anything but. Sometimes however, animals use a habitat only because they have little choice — in other words, they are making the best of a bad situation. The job of a good wildlife biologist is to understand the difference. Unfortunately, it’s often not obvious.

In all the places studied by this author — Tierra del Fuego, the Arctic, and many places in between — knots distinguish themselves as highly selective habitat specialists. There are many practical reasons for this: usually knots occur in flocks and thus require more space than many other species. More importantly, as they put on weight for their incredibly long-distance flights, they often push the limit of safe wing-loading (body weight to wing area). This makes them vulnerable to predators, both real and imagined. They need more flying space, more space for advance warning of a predator’s presence. They demand special roost habitats as well, especially night roosts that are free from disturbance and have good sight distances. Altogether they need more.

Red knots roost on a sandy spit on Egg Island, one of the largest contigous area of marsh in the mid Atlantic. Half of the bay's shorebird population roost on Egg Island and than feed on the various beaches around Fortescue. — Red knots roost on a sandy spit on Egg Island, one of the largest contigous area of marsh in the mid Atlantic. Half of the bay’s shorebird population roost on Egg Island and then feed on the various beaches around Fortescue.

In Delaware Bay, they need all this, but above all they need good horseshoe crab egg densities. In the mid 2000’s when shorebird numbers were high, the demand for those eggs exceeded the production from the rapidly diminishing crab population. Knots wandered the bay like homeless refugees. Competition for eggs drew tens of thousands of birds to places unused by knots in healthier times.

Mispillion Harbor, Delaware, for example, in some years supported much of the knot population in the Bay because it acts like a funnel-trap for crabs. Crabs wandered into the harbor through long stone jetties finding themselves in crab breeding heaven, sandy shoals in a closed space, free from wind-generated waves that normally leave them upside down. The egg-laying frenzy caused eggs to reach epic densities, thus preparing many shorebirds for their onward journey to the Arctic. Tens of thousands of shorebird packed into Mispillion Harbor in densities so high that one could smell ammonia off-gassing from the amount of bird waste.

But for knots, Mispillion left a lot to be desired. The same jetties that protect the inner harbor from wind-driven waves also provide low-flying raptors the cover to pounce on flocks before they can easily react. Fat birds make easy prey for peregrine falcons, who themselves struggle to keep up with the insatiable hunger of rapidly growing chicks.

But even as shorebird numbers fell in response to the reduced crab numbers, egg densities improved in other places. Knots reassessed their choices and voted with their wings.

This is why this year’s high count of red knots on the New Jersey side of the Bay are so important. Two days ago, Mark Peck, Joe Smith and I flew the entire Bay to count knots, ruddy turnstones and sanderlings. We counted over 24,000 knots, with 21,000 of these using the beaches managed by the many groups that take part in shorebird management on the New Jersey shore of Delaware Bay.

I am not saying this is a competition between two states — I’m saying the numbers serve as assurance that all our hard work is paying off. It’s a confirmation that the beach restoration projects, the Shorebird Stewards project, the reTURN the Favor crab rescue project, and more are bearing fruit. These coordinated strategies are led by Conserve Wildlife Foundation of New Jersey, American Littoral Society, Manomet Center for Conservation Sciences, New Jersey Audubon Society, the Wetlands Institute, Citizens United to Protect the Maurice River, The Nature Conservancy, as well as Downe Township, Maurice River Township, Middle Township and the Division of Fish and Wildlife, New Jersey Department of Environmental Protection. This work is funded by the US Department of Interior, Fish and Wildlife Service, the National Fish and Wildlife Foundation and the Willliam Penn Foundation. Good work all!

Jim May protect Cook Beach as part of Conserve Wildlife Foundation of NJ's Shorebird Stewardship Project. Each year the Division of Fish and Wildlife designates beaches important to shorebirds and protects them from disturbance. The shorebird stewards alert Conservation Officers if people refuse to comply. But most of thier job is helping people understand the shorebird migration and the needs of shorebirds and crabs — Jim May protects Cook Beach as part of Conserve Wildlife Foundation of New Jersey’s Shorebird Stewards project. Each year, the Division of Fish and Wildlife designates beaches that are most important to shorebirds and protects them from disturbance. The shorebird stewards alert Conservation Officers if people refuse to comply, but most of their job is helping people understand the shorebird migration and the needs of shorebirds and crabs.

We now near the end of the stopover season at Delaware Bay. Three days of southerly winds are proving irresistible for many birds. Nearly two-thirds have left and the rest will be gone in a few days. Thanks to the people who love birds and the residents of the Bay, they leave well-prepared for the next stage of their challenging and inspiring lives.

knots in the air

Learn more:

Dr. Larry Niles has led efforts to protect red knots and horseshoe crabs for over 30 years.

19,077 Red Knots Counted – The Most Seen in New Jersey in a Decade

Posted on May 25, 2015 by CWF

An Update on the 2015 Delaware Bay Shorebird Project

By: Dr. Larry Niles, LJ Niles Associates LLC

Despite the threatening forecast of a cold drizzle and strong winds, our team persevered to complete the first bay-wide count of this season. On the New Jersey side of Delaware Bay, we counted 19,077 red knots – the most seen in the state in a decade. With Delaware’s shorebird team recording 2,000 knots along their entire shoreline, the total knot count of 21,077 is not far from the 24,000 seasonal maximum of the last three years.

This is good news in either of two completely different ways. One explanation is that perhaps most of the knots have already come to the bay. If so, they are in good time to make weight and are getting close to an on-time departure for the Arctic. The alternative is that even more will arrive and we will exceed our counts of the recent past. Good weights promise good Arctic production; more knots offer new hope.

Knots in formation heading off to the Arctic (c) Jan van de Kam

The numbers of ruddy turnstones (12,295) and semipalmated sandpipers (56,788) are also close to the seasonal maxima counts of the recent past, so they too may soon brave the long flight to their Arctic homes. Our cannon-net catches of turnstones, sanderlings and knots point to weights building quickly.

The weather conditions play with our expectations. For the last few days, high westerly winds have generated beach-pounding waves all along the Cape shore. Its north/south orientation is perfectly perpendicular to the strong winds, and the wind-generated waves shut down horseshoe crab spawning. This forces the birds to seek shelter and better egg densities elsewhere.

Right from the start, the disappearance of the shorebirds we had been seeing intrigued us, for a good wildlife mystery gets consumed in this team like a good bottle of beer. Within hours, Mark Peck and Gwen Binsfeld found the knots south of where we would have expected. The knots, turnstones, sanderlings, and semipalmateds were comfortably riding out the wind storm on the vast, sandy intertidal flats in front of Sunray Beach and Villas. We haven’t seen birds gathering in numbers here since the early 2000’s.

Photo of shorebird team by Kevin Karlson (from bottom right: Mark Fields, Stephanie Feigin, Mark Peck, Clive Minton, Angela Watts, Jeannine Parvin, Christophe Buidin, Alinde Fojtik, Dick Veitch, Barrie Watts, Joanna Burger, Arie Manchen, Steve Gates, Phillipe Sitters, Ana Paula Sousa, Reydson Reis, Chege Wa Karuiki, Susan Taylor, Mandy Dey, Peter Fullagar, Deb Carter, Gwen Binsfeld, Nick Smith, Clara Kienzi, Joe Smith, Larry Niles, Humphrey Sitters, Stefanie Jenkinson, Ally Anderson, David Stallneckt, Gerry Binsfeld, Christian Friis, Chris Davey)

But back to the count. We found shorebirds all along the Bayshore with three areas of concentration. The first was the aforementioned Villas flats. The second was in the Pierces Point to Reeds Beach area, with most in the more southerly portion of the sector. “Not-knots” (mostly semipalmated sandpipers) were seen there in big numbers during the boat survey by Yann Rochpault, Christophe Buidin and Tom Baxter. They saw 12,000 shorebirds along this mostly unpopulated shoreline.

Semi palmated sandpipers along shoreline (c)Jan van de Kam

But the real shorebird wonderland of the bay continues to be Egg Island. Few people see this this vast intertidal marsh, and fewer still appreciate its wonder. Egg Island – actually a peninsula – juts miles out into the bay, nearly to the shipping channel. The marsh cradles one of the most diverse bird faunas of the mid-Atlantic. All along its mucky eastern flank, short-billed dowitchers, dunlin, semipalmated sandpipers, black-bellied plovers, and semipalmated plovers comb the eroded banks for crab eggs drifting in the water column from better crab breeding sites. The crabs themselves attempt to breed in the overhanging edges of the spartina marsh, a lost cause; however, because the muck lacks oxygen and the eggs cannot develop. This is bad for crabs but good for shorebirds because most of the eggs end up on the sod banks, easy prey for shorebirds.

birds on sod

But this week, the wonders of Egg Island overwhelmed us. Our team – Humphrey Sitters, Phillipa Sitters and this blog’s author – wove along the shallow shoreline in our intrepid 17-ft Carolina skiff, counting thousands of shorebirds – 8,226 knots, 4,125 ruddy turnstones, 3,000 sanderlings, and 21,000 semipalmated sandpipers. The flocks swirled around the peninsula’s sandy western shore, alighting, then flying, and then alighting again. It was a shorebird dance that was a wonderful sight for increasingly tired-out shorebird scientists.

Learn more:

Dr. Larry Niles has led efforts to protect red knots and horseshoe crabs for over 30 years.

13,000 Red Knots on New Jersey’s Delaware Bay

Posted on May 21, 2015 by CWF

An Update on the 2015 Delaware Bay Shorebird Project

By: Dr. Larry Niles, LJ Niles Associates LLC

We had about 13,000 knots on the New Jersey side of the Delaware Bay (an additional reported 2,000 on the Delaware side of the Bay). Yesterday, we suffered strong NW winds in excess of 20 kts and the birds virtually disappeared. Our daily survey turned up about 6,000 knots, the rest we suspect, finding refuge in Egg Island and Goshen Marshes or with a flyover to Delaware.

We will know where they went today. The team will comb the Bayshore for shorebirds with a coordinated ground, boat and aerial survey. The birds gain weight in good time and we expect the first Arctic lift-offs by the 26th. At the current rate, most of the Bay’s population will be off to the Arctic by the 30th.

Above is a clip from a new video about knots and our work by Mitch Smith, a longtime supporter of the team and head of the Mitch Smith Media.

Learn more:

Dr. Larry Niles has led efforts to protect red knots and horseshoe crabs for over 30 years.

2015 Horseshoe Crab Spawn and Shorebird Migration on Delaware Bay

Posted on May 20, 2015 by CWF

An Update on This Season’s Horseshoe Crab Spawn and Shorebird Migration, Ten Days In

By: Dr. Larry Niles, LJ Niles Associates LLC

Thousands of shorebirds now fill Delaware Bay’s beaches and marshes in a determined effort to regain lost reserves with free-for-the-taking fatty eggs of the horseshoe crab. The crab spawn began ten days ago and has gained momentum over the last week as the volume of eggs grows like a well-funded savings account. The eggs surface as each new female crab digs up egg clusters laid by other crabs or as wind-driven waves pound the always-fluid sandy beaches. At least 8,000 red knots slowly get fat on the eggs scattered on New Jersey’s Delaware Bay beaches.

Both crabs and birds are the beneficiaries of the increasing number of beaches that are highly suitable for egg-laying. In October, 2012, Hurricane Sandy ravaged two-thirds of New Jersey’s best crab-spawning beaches, its strong westerly winds lifting sand and spreading it far from the sea’s edge. Left behind was a jagged sod bank, completely unsuitable for horseshoe crab breeding. The mucky sod starves eggs of oxygen or gasses them with hydrogen sulfide, the by-product of decaying mud.

The American Littoral Society, Conserve Wildlife Foundation of New Jersey, the U.S. Fish and Wildlife Service and the National Fish and Wildlife Foundation came to the rescue, restoring many of these beaches to a condition superior to that before Sandy. The restoration team even repaired damages that predated Sandy — beaches with tons of rubble that entrapped crabs in nasty concrete, killing them by the thousands. Now beaches like Thompson’s Beach and Fortescue Beach join the growing number of delicate sandy strands that provide excellent spawning habitat.

Thompsons Beach Before and After — Thompson’s Beach Before and After Restoration

This week, eggs can be found in many places on the New Jersey side of Delaware Bay, and the birds have the freedom to move to those that best suit them. Earlier this month, strong northwest winds drove red knots from the Reeds Beach area to other, more northerly, beaches that saw good crab spawning — beaches that also provide shelter from the winds. Now that the wind and sea have calmed, the birds have returned to the Reeds Beach area, less than 20 miles away, and have resumed gorging on the plentiful eggs that built up in their absence.

Early Morning Shorebirds on Delaware Bay

If one were to look for any cloud on the Delaware Bay shorebird horizon, it would lie in the lack of any evidence of horseshoe crab recovery. The current, reduced, population of crabs spawned eggs in great numbers early this May because of a spike in the water temperature, a consequence of unusually warm weather. So far the promise of this early spawn is holding, and crabs continue to spawn in good numbers. But will it hold until the end of May?

If not, the readers of this blog will witness the outcome. The graph below, developed by long-time team-member Dick Veitch tells the story of a past egg failure. In the early 2000’s, although the population of shorebirds had not yet declined to its current number, the crab population had already fallen to its current number, crushed by the onslaught of a poorly regulated fishing industry. In those years, all the horseshoe crabs that could spawn had finished by the third week of May and egg densities on the bay plummeted. The birds crammed into the few beaches with eggs like Mispillion Harbor, Delaware, so densely that the beach reeked of off-gassing urinary ammonia.

But the number of eggs there was not sufficient to feed the still-large shorebird populations and birds failed to reach a weight – about 180g for red knots — suitable for their journey to the Arctic and subsequent breeding. Where once 80% reached the “good” weight, only 5% did in 2003 (see the second graph).

Percentage of Red Knots Reaching 180 Grams

The percentage has improved thankfully, but only because the number of shorebirds have fallen over the last 10 years, bringing a balance of sorts. Hopefully, with the new beaches, the new protection afforded by the red knot listing and the growing number of volunteers taking part in conservation of the crab and birds, this kind of disaster is behind us.

We shall see.

Learn more:

Dr. Larry Niles has led efforts to protect red knots and horseshoe crabs for over 30 years.

2015 Delaware Bay Shorebird Project Continues!

Posted on May 17, 2015 by CWF

Another Season of the Delaware Bay Shorebird Project Underway

By: Dr. Larry Niles, LJ Niles Associates LLC

The value of a shorebird stopover like Delaware Bay can be seen in the shaky cam movie by this author. Red knots – some recently arrived after a grueling 6,000-mile flight over 6 days of continuous flying – arrive on the Bayshore desperate for food. Over the last 10,000 years, the species has evolved to fly directly to the Bay to feed on the eggs of the horseshoe crab.

The 450-million year-old crab – which is actually in the spider family – crawls ashore and lays pin-sized eggs about 6 inches deep in the sand. When there are many crabs, as here on Delaware Bay, one crab often unearths the eggs of another. Thus they leave millions of fatty eggs on the surface, offering an energy-rich, soft feast for the starving birds. In turn, we get to watch the birds racing for an egg ‘hot spot’!

The birds often arrive beyond depleted. A normal weight for a knot is 130 grams. Many arrive on Delaware Bay below 100 grams, the equivalent of a human in the throes of profound starvation. But when the birds fly north from the coast of northern Brazil, there’s no turning back. Once they go, they must go all the way.

Map of geolocator track of a South American wintering red knot

This year, migrating shorebirds faced a freak tropical storm that could have forced them out to sea, far off-course. In severe cases, some birds with no remaining fat reserves even metabolize their own muscles, like airplanes throwing out vital equipment to stay aloft. Storms can also prevent birds from lifting off on migratory flights. They are capable of detecting atmospheric pressure changes and can just stay put until a storm passes. We think this is what happened this week when a storm, followed by a strong cold front and consequent northwest winds, prevented a movement north.

The sum of these challenges was lower than normal shorebird numbers during the first week of the stopover. The Heislerville impoundments support a good number of short-billed dowitchers and dunlin, but these species usually arrive earlier than the others and probably came in ahead of the adverse winds. Yet there are very few ruddy turnstones, sanderlings and semipalmated sandpipers on the Bay.

Short bill dowitcher (c) Jan van der Kam from Life on Delaware Bay

The one exception on the Bay is the red knot. At first, we thought that only about 1,000 red knots had arrived in and around Reed’s Beach. Then Jerry Binsfeld and Peter Fullagar, Canadian and Aussie members of our team, found an amazing 7,000 knots at Gandys Beach on the northern Bayshore in New Jersey. Very likely, these are short-distance migrants, coming in from wintering areas in Florida, Georgia and the Caribbean.

Our catch results support this working hypothesis. The knots we caught at Fortescue were at higher weights than normal for this early part of the season, which would be expected if fewer very thin long-distance migrants were part of the average.

The graph shows the weight relative to previous years.

The histogram shows the distribution of all the birds weights in the catch.

Learn more:

Dr. Larry Niles has led efforts to protect red knots and horseshoe crabs for over 30 years.

2015 Delaware Bay Shorebird Project Begins!

Posted on May 12, 2015 by CWF

Another Season of the Delaware Bay Shorebird Project Underway

By: Dr. Larry Niles, LJ Niles Associates LLC

Our 2015 Delaware Bay Shorebird Project began on one of the hottest early-May weekends in memory. Clive Minton, an English-expatriate Australian, and I began the project with an early morning survey of each bay beach – Reeds, Cooks, Kimbles, Pierces, Rutgers, Norburys, Villas – dripping sweat and swatting biting gnats as though it was early June, not early May. The sudden burst of summer weather warmed the bay waters, triggering our first horseshoe crab spawn providing sufficient eggs for newly arriving birds.

Delaware Bay Team 2015

The birds, on the other hand, followed a more normal schedule. We counted only 400 knots, a smaller number of ruddy turnstones and, surprisingly, no sanderlings. We know the birds are en route; Pat Leary in Florida and Fletcher Smith in Georgia report good numbers of knots, but the birds appear stuck because of the unsettled weather and the rare occurrence of a tropical storm making landfall in North Carolina over the weekend. Soon enough they will come.

Red Knot Photo by: Pat O'Leary — Red Knot Photo by: Pat O’Leary

The warm weather and the abundant crab spawn bode well for the birds – we want the early bird to gets eggs. But they point to one of the many difficulties facing the red knot and other shorebirds. Will the insidious effects of climate change unravel this elegant machine that provides horseshoe crabs eggs just at the time Arctic-nesting shorebird need them to fly on to their breeding areas?

Our project is 19 years old and so provides a perspective virtually unique among wildlife projects. A long-running project of this kind has many advantages, not the least of which is the human family that has formed around our love of birds. We have nearly the same core team in 2015 as we did in 1997, losing and gaining a few team members as time marches on, but always maintaining an esprit de corp, a common purpose, a lasting bond. The shorebirds, the crabs and the many people who love the Delaware Bay owe a debt of gratitude to this team of intrepid researchers.

The project’s longevity also creates a perspective rare in the world of bird study. Over 19 years we have seen the collapse of the horseshoe crabs; the dramatic free fall of the red knot that resulted this year in a federal listing as Threatened; the rise of irresponsible commercial exploitation of the natural wealth of the bay; a devastating hurricane and more. And yet each year the birds arrive, the crabs spawn and our team coalesces from every corner of the world. Despite the problems and all the concern, the system persists.

But how long will the system persist?

The challenges faced by the birds grow every year. They cling to this amazing migratory bird like barnacles on a wooden boat. Crabs have not recovered from the devastating overharvest of 15 years ago. The international drug cartels still drain the blood of crabs for the valuable chemical lysate without any responsible management. All the while shorebirds, the red knot in particular, face growing threats from climate change: more frequent storms, destroyed coastal habitat, rapidly-changing arctic tundra habitats.

Lysate Industry

Herein lies the value of a long-term study. This season’s unprecedented early spawn and warm weather could be good or bad. Either way, by season’s end, the team’s dedication, skill, and plain hard work means we will know what happened and what it means compared to 18 other years.

Early Red Knots on Baycove Beach on Delaware Bay

Learn more:

Dr. Larry Niles has led efforts to protect red knots and horseshoe crabs for over 30 years.