CWF Biologists Travel to Brazil to Study Red Knots

On our Expedition to Study Shorebirds along the Northern Coast of Brazil

By: Dr. Larry Niles, LJ Niles Associates LLC

Ana Paula with Red Knot
Ana Paula with Red Knot

The largest mangrove forest in the world covers the Brazilian coastline at the equator near the mouth of the Amazon river. The forest extends out into the Atlantic in long peninsulas tipped by wind swept and mostly inaccessible beaches. The forest, beaches and their long intertidal mud and sandy low tide flats support the largest wintering population of shorebirds in the hemisphere, perhaps the world. The red knot, a listed species in both North and South America, also uses this remote tropical coast.

Boat Trip Route
Boat Trip Route
Catamaran
Catamaran

 

 

 

With scientists from the U.S., Canada, England and Brazil, we will attempt a large scale mapping of this important habitat using state-of-the-art satellite mapping. We will do this from a 50-foot catamaran and two zodiacs hopping from one mangrove estuary to another and conducting bird surveys targeting key areas over a 150 mile-section of the coast. We will be the first to survey some areas. Our goal is to figure out the main threats to both bird and habitat.

 

 

To understand the importance of this area one has to think about it like a shorebird. Although born in the Arctic they actually spend only a few months there. They spend a few months moving from their nesting area to their wintering area. They spend the rest of their lives, the majority of their year in the wintering area. A threat to the wintering area would be grave.

 

Most of our survey zone is part of the Reentrancias Maranhenses, a protected area of the state of Maranhao, Brazil. Our catamaran captained by William Thomas will leave from a small town near the city of Sao Luis, Brazil. From there we will sail along the coastline moving in and out of the mangrove islands to survey shorebirds, habitat and marine invertebrates. We will “geo reference” all data, or take detailed coordinates so the data can be reproduced on satellite mapping.

Satellite Map
Satellite Map

 

Satellite maps aren’t really maps as most people understand — pictures or drawings of a section of the earth — they are digital files of remotely sensed data, they are only wavelengths of light that must be interpreted to represent actual habitat. We will train the satellite data so that each habitat will be represented by a combination of spectral data — colors in sense.

Environmental disturbance. Photo by Mark Peck.
Environmental disturbance. Photo by Mark Peck.

Once completed, we can relate the habitat maps with information on birds, their prey and equally important, the threats to the birds and prey. For example, shrimp farming is growing in this area. Entrepreneurs are stripping the intertidal zone of mangrove forest, diking the area and then growing shrimp. Once the area accumulates too much waste and chemicals, they abandon the site and move on to damage another mangrove forest. We will determine which areas are of importance to the birds and potential targets for shrimp farmers. But there is more: oil spills, disturbance from tourists, water pollution are among many.

 

Over the next three weeks, we will be reporting on our work on this blog.

Log of Red Knot DbY7 with geolocator.
Log of Red Knot DbY7 with geolocator.

 

Learn more:

 

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

Banding Together: When the Shorebird Met the Biologist

Celebrating World Shorebirds Day, Sunday, September 6

by Lindsay McNamara, Communications Manager

Red Knot Photo by: Jan van der Kam
Red Knot Photo by: Jan van der Kam

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
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.
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.
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

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
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.

Photo by Kevin Karlson
Photo by Kevin Karlson

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.
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 20th 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 20th 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
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”

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.

Red Knot Photo by: Jan van der Kam
Red Knot Photo by: Jan van der Kam

 

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
Mispillion Harbor

 

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.

Photo by:  Jan van der Kam
Photo by: Jan van der Kam

 

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.

 

Delaware Bay Shell-a-Bration Captured on Video

South Reeds Beach Oyster Reef Event Filmed by Local Delaware Bay Producer

By: Lindsay McNamara, Communications Manager

A record number of Red Knots were counted on New Jersey’s Delaware Bay this year, in part because of innovative restoration projects like our South Reeds Beach oyster reef.

 

Over 130 volunteers and veterans worked alongside Conserve Wildlife Foundation and American Littoral Society to establish a near-shore whelk shell bar at South Reeds Beach in Cape May Court House on the Delaware Bayshore in early April.

 

Shorebirds, like the federally listed Red Knot, depend on an uninterrupted supply of horseshoe crab eggs when they stopover in Delaware Bay during their migration. In recent years, countless horseshoe crab eggs have been lost because of the devastating storms that swept away the beaches they depend on.

 

The oyster reef was built to prevent sand loss from wind-driven waves. The approximately 200-foot project will test whether the reef bars help reduce beach erosion and create calmer water for spawning horseshoe crabs.

 

Learn more about the project and our “Shell-a-Bration” event in the video above produced by Kathleen Poliski of K. Productions, LLC!

 

The South Reeds Beach Oyster Reef is one of the many projects that American Littoral Society and Conserve Wildlife Foundation are working on to restore the ecology and economy of the Delaware Bayshore, thanks to generous funding by the National Fish and Wildlife Foundation. To learn more, visit RestoreNJBayshore.org.

 

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

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

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.

 

Red knot aerial counts
Red knot aerial counts

 

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
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.

 

Canon net catch
Canon net catch
Canon net catch
Canon net catch
Canon net catch
Canon net catch

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)
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
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

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

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.

Eggs on Beach
Eggs on Beach

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
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?

Crabs in Slew
Crabs in Slew

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
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!

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
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
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.

Red Knots on Fortescue
Red Knots on Fortescue

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 graph shows the weight relative to previous years.
The histogram shows the distribution of all the birds weights in the catch.
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.

Conserve Wildlife Foundation of New Jersey “2014 Annual Report” Released

CWF Releases its First Annual Report Ever Using a Story Map Format: “2014 Annual Report

By David Wheeler, Executive Director

Technology has proven to be vital to Conserve Wildlife Foundation’s work protecting rare wildlife species over the years. Our biologists depend greatly on modern technologies to band, track, and share online the journeys of wildlife. Our webcams broadcast the most intimate behaviors of nesting birds and bats across the web. And we seek out ever-evolving communications technologies to spread the word about the inspiring stories of wildlife, from social media and infographs to e-books and Story Maps. These technologies offer newfound abilities to share complex data on multiple levels, while still incorporating the awe-inspiring photography and videos that bring wildlife’s stories to life.

Conserve Wildlife Foundation of New Jersey is excited to offer our 2014 Annual Report in a unique format that utilizes one of those technologies – Story Maps. In the past year, we have explored the wonders of American oystercatchers with our first Story Map – and now the annual report allows all of our projects to be highlighted in this interactive format.

A screen capture of one of the pages of the CWF 2014 Annual Report Story Map.
A screen capture of one of the pages of the CWF 2014 Annual Report Story Map.

Visit the multiple pages within this Story Map to learn about Conserve Wildlife Foundation’s many projects and partnerships in 2014, and the imperiled wildlife species in need of our help. Find examples of the innovative and dedicated leadership of our biologists and volunteers. And take an online journey across the state to learn how our projects made a difference in all corners of New Jersey in 2014 – a great year for wildlife in the Garden State!