NEW, WEEKLY UPDATES FROM NEW JERSEY’S BEACH NESTING BIRD PROJECT TEAM
by Todd Pover, Beach Nesting Bird Project Manager
Least tern photo by Northside Jim.
Piping plovers tend to garner most of our attention on the beach nesting bird project because they are so critically endangered. American oystercatchers and black skimmers are visually striking and very charismatic, so they are popular with the public, as well. That sometimes leaves the least tern as the “forgotten stepchild” of our beachnesters.
Their protective behavior of dive-bombing and even pooping on beachgoers who get too close to their nests or young doesn’t help their reputation. Yet, they are a fascinating species to watch and their chicks rank high on the cute scale.
Because they are a colonial species, and the colonies often take up large areas of the beach, they are a special challenge to manage and protect. But they do need protection – they are listed as endangered in New Jersey. Over the past decade, their population has remained low but stable. On one hand that is good, it means they aren’t declining further, but it also means they aren’t recovering either.
This week, we completed the latest of our bi-monthly surveys with a total of about 1200 individuals counted. This is below our peak a little earlier in the month, but in line with our typical statewide population. To date, we have recorded 24 active colonies along the coast from Sandy Hook to Cape May this year. That is within our average annual range of 20-25, although several of those colonies have already failed due to intense predator pressure.
It is too early to say whether this will be a good or bad year for least terns. We are in the peak period for chicks, so the next two weeks or so will determine if we successfully produce enough young to the fledgling stage. In the meantime, now is the time to get out to see these cuties, but remember to view them from a safe distance and share the shore with all our beach nesting birds.
At 8:00 PM on October 29th, 2012, Hurricane Sandy made landfall in Brigantine, New Jersey, only about 30 miles from New Jersey’s Hidden Coast – the Delaware Bayshore. The storm was devastating for the people of the area, many of whom lost their homes and livelihoods. It was equally hard on the area’s wildlife, bringing many species, including the famous horseshoe crab and red knot, perilously close to extinction.
A new episode of our video series “New Jersey’s Hidden Coast” will air every two weeks throughout the summer! Catch a glimpse of the bay, the horseshoe crab at the center of the bay’s system, and the incredible relationship between horseshoe crabs and migratory birds, like the red knot. We will reveal the real value of horseshoe crabs, the challenges to the ecosystem, and the potential for a thriving regional economy along the Bayshore. We will show Hurricane Sandy as a catalyst for decisive action and the work being done to rebuild the area for both people and wildlife.
Over the next several weeks, we will explore the use of “living shorelines” instead of bulkheads and the central importance of marshes to the marine ecosystem. We will discover the on-the-ground, grassroots efforts of the community to build oyster reefs alongside veterans. And we will examine the future of the Bay and the work that needs to be done to preserve our conservation successes thus far.
NEW, WEEKLY UPDATES FROM NEW JERSEY’S BEACH NESTING BIRD PROJECT TEAM
by Todd Pover, Beach Nesting Bird Project Manager
Amazing transformation of a piping plover from tiny chick to fledgling in just 25 days. Both photos by Northside Jim.
The highlight of this past week was our first piping plover fledglings of the season. This means the first group of chicks has reached the stage where they can fly, which is our metric for success. Hatching the chicks is always great, but our goal is population recovery and the primary way we can increase our low population in New Jersey is to produce more fledglings to come back in future years to breed here.
The doubly exciting news is ALL four of the chicks that hatched at Barnegat Light reached the flying stage. This is notable because typically, on average, we only fledge about one chick per pair in New Jersey. This is not enough to grow or sustain our long-term population. Population modeling tells us we need to fledge about 1.5 chicks per pair range-wide to grow the population and about 1.25 chicks per pair to sustain it.
Of course, not all our piping plover pairs will fledge four chicks, in fact, some may not fledge any. So the Barnegat Light news was a good way to kick off our fledgling season and hopefully it is a sign of above average productivity this year.
NEW, WEEKLY UPDATES FROM NEW JERSEY’S BEACH NESTING BIRD PROJECT TEAM
by Todd Pover, Beach Nesting Bird Project Manager
Least tern photo by Northside Jim.
The beach nesting bird field staff is firing on all cylinders now, frantically trying to keep up with nesting activity. In some regions of the New Jersey coast, piping plovers and American oystercatchers are still laying eggs, while at other sites there are chicks on the beach, even one site (Barnegat Light) where the chicks are already approaching their “fledgling” stage when they will be able to fly.
CWF Field Technician Jesse Amesbury busy conducting annual piping plover census at Edwin B. Forsythe NWR.
Most of the least tern and black skimmer colonies are now established, with least terns starting to hatch chicks and black skimmers just laying eggs. Counting the colonies is one of the most challenging parts of the job, imagine trying to count 1,000-1,500 birds at a time in some instances!
After helping with the winter segment of the International Piping Plover Census in the Bahamas, CWF switched gears this week to help conduct the breeding portion in New Jersey.
All the normal beachnester tasks are keeping us busy, but the main focus this past week was the annual piping plover “window” census, where field biologists all along the Atlantic coast count the number of birds present between June 1-9, so we can get a range-wide breeding population estimate. As for New Jersey, it looks like our population will go up, at least slightly, for the second year in a row. Although this is still a very preliminary estimate, it looks like we have weathered the statewide low in breeding pairs we recorded in 2014, thanks to good productivity the past two years.
Of special note is a spike in Monmouth County (outside Sandy Hook), where we have gone from 2 pairs the past several years to 12 pairs this year. Although a smaller bump, we also went from 1 pair to 4 pairs within Barnegat Inlet, an area we have long hoped for more pairs. It takes a tremendous effort to realize even small gains in our piping plover recovery effort, so we are especially excited about this news!
Our work is never done…CWF Wildlife Biologist Emily Heiser posting a new nesting area for endangered least terns.
Horseshoe crabs may be one of the most unusual animals in the world, but they’re also one of the most extraordinary. They’ve been around for hundreds of millions of years, and we’re only now starting to understand just how important they are – not just to the natural world, but also to the world of medicine. Discover the real value of horseshoe crabs, found throughout New Jersey’s Hidden Coast – the Delaware Bayshore.
A new episode of our video series “New Jersey’s Hidden Coast” will air every two weeks throughout the summer! Catch a glimpse of the bay, the horseshoe crab at the center of the bay’s system, and the incredible relationship between horseshoe crabs and migratory birds, like the red knot. We will reveal the real value of horseshoe crabs, the challenges to the ecosystem, and the potential for a thriving regional economy along the Bayshore. We will show Hurricane Sandy as a catalyst for decisive action and the work being done to rebuild the area for both people and wildlife.
Over the next several weeks, we will explore the use of “living shorelines” instead of bulkheads and the central importance of marshes to the marine ecosystem. We will discover the on-the-ground, grassroots efforts of the community to build oyster reefs alongside veterans. And we will examine the future of the Bay and the work that needs to be done to preserve our conservation successes thus far.
Discover New Jersey’s Hidden Coast – the Delaware Bayshore
by Lindsay McNamara, Communications Manager
Making your plans for Memorial Day Weekend at the Jersey Shore? Discover New Jersey’s “other” coastline, a Hidden Coast, the Delaware Bayshore.
A new episode of our video series “New Jersey’s Hidden Coast” will air every two weeks throughout the summer! Catch a glimpse of the bay, the horseshoe crab at the center of the bay’s system, and the incredible relationship between horseshoe crabs and migratory birds, like the red knot. We will reveal the real value of horseshoe crabs, the challenges to the ecosystem, and the potential for a thriving regional economy along the Bayshore. We will show Hurricane Sandy as a catalyst for decisive action and the work being done to rebuild the area for both people and wildlife.
Over the next several weeks, we will explore the use of “living shorelines” instead of bulkheads and the central importance of marshes to the marine ecosystem. We will discover the on-the-ground, grassroots efforts of the community to build oyster reefs alongside veterans. And we will examine the future of the Bay and the work that needs to be done to preserve our conservation successes thus far.
One of a Series of Updates on the 20th Year of the Delaware Bay Shorebird Project
by Dr. Larry Niles, LJ Niles Associates LLC
In spite of the very spotty horseshoe crab spawn, the shorebirds on Delaware Bay seem to be gaining weight on schedule. Below you will find a graph composed of the average weights of all the red knots by our team for the last 20 years. The curve is the result of combining all the data we collected and shows the sweet spot for most knots. As they arrive, they take time to gain weight but after about 5 days they start gaining weight rapidly. After the 26th or so, birds start reaching the critical weights necessary to safely reach the Arctic breeding grounds. One can see the curve deep at the end of the month because fat birds fly off leaving the less fat behind. In general, weights above the line are good, below the line not good. The large squares on the graph are the average weight of this year. So far, so good.
Average Red knot weights from catches made in 1997 to 2016. The most recent are the big squares. So far average weights are following normal pattern of weight gain.Cannon net firing over red knots on Delaware Bay
This is a bit of a surprise for the team. The weather here on Delaware Bay is wet and cold. The water temperature struggles to lift above 59 degrees, the temperature necessary for a crab to spawn on Delaware Bay. So far, the temperature has been below 59 degrees more than above. We had good spawns in the last few days, but only in key places.
Water temperature at the mouth of Delaware Bay.
A key place for horseshoe crab spawn happens to be the mouths of small creeks. The New Jersey side of Delaware Bay is blessed with many small intertidal creeks, most draining only marsh or small inland watersheds. Some of these creeks have names, Goshen Creek, West Creek, Nantuxent Creek, but many do not. Almost all have shoals at their mouth with the bay because bay currents, tidal flow and wind driven waves act against each other to settle sand coming from adjacent beaches or from inside the creek drainage. Much of the sand lost from our restored beaches settles into these shoals. For horseshoe crabs, these shoals are sweet places.
A sandy shoal at the mouth of the nameless creek between Reeds and Cooks Beach. At the time of this picture, over 3,000 knots and 1,000 ruddy turnstones were using the shoal and the inner sandy beach behind the shoal. Photo by Stephanie Feigin.Red Knots in flight on Cooks Shoal. Photo by Stephanie Feigin.Red Knots on Cooks Shoal. Photo by Stephanie Feigin.Red Knots on Cooks Shoal. Photo by Stephanie Feigin.
Usually, the shoals lie just under the high tide line and are composed of large grain sand, the optimal conditions for a good crab spawn. However, the most important characteristic and key to this unusually cold May, is the warming water flowing out from the marsh drainages. On a flooding tide, colder warmer flows into the vast marshes of the Delaware Bay. This warms the water. On an ebbing tide, it flows out the creek and over the shoals, making them slightly warmer and more conducive to inducing crabs to spawn. Even on these cold days, they literally climb over themselves to breed on the shoals. The shoals also protect the inner mouths of the creeks thus making the sandy shores at the mouth of the creek a crab spawning heaven.
Breeding horseshoe crabs. Photo by Jan van der Kam.
However, as it seems usual with this blog, there is a growing concern. Right now, most of the red knot population on the bay is feeding on these shoals along with thousands of other species, but only half have arrived from southern wintering areas. We now have about 12,000 red knots on the bay and in a day or two we should find another 12,000 falling from the sky. Will there be enough eggs? Will the water temperature finally reach normal levels? These are the important question for the next few days.
New, weekly updates from New Jersey’s beach nesting bird project team
by Todd Pover, Beach Nesting Bird Project Manager
American oystercatcher Chick
It has been a busy week on the beach nesting bird project! We had our first least tern nests of the season, as the brief spell of warmer weather (finally) made for a burst of breeding activity. The first American oystercatcher nests hatched, so we have chicks on the beach now, as well.
Least Tern Nest
And there was a big spike in new piping plover nests all along the coast, so we were busy erecting “predator exclosures” to protect the eggs from predators, such as crows, cats, gulls, and foxes. While they are not effective or viable to use on every nest, these wire cage structures are one of our best management techniques to increase hatch success by deterring predators.
Piping Plover Exclosure
This week we will be even busier, as we make a mad scramble to protect the nests and colonies before the crowds of beachgoers arrive for the Memorial Day weekend!
One of a Series of Updates on the 20th Year of the Delaware Bay Shorebird Project
By: Dr. Larry Niles, LJ Niles Associates LLC
Shorebirds and no horseshoe crabs along the Bay.
It’s well known that the Delaware Bay shorebird stopover depends on horseshoe crabs, but few know that Delaware Bay is a near perfect horseshoe crab habitat.
There are many places on the eastern seaboard where horseshoe crabs breed. Most are too small to provide sustenance for energy-starved shorebirds. Places like Cape Romain Refuge in South Carolina have enough horseshoe crabs so that one breeding female unearths eggs of another and thus lays out a tidy meal for shorebirds. But the areas are small and at this time unimportant to the population of shorebirds. Most of the others are too small to have eggs reach the surface. Its only in Delaware Bay where crab numbers reach into the millions and spawn in such great numbers that they spread like a carpet over nearly all beaches from Gandy’s Beach to Villas, approximately 20 miles of spawning habitat. The number of eggs and ultimately hatched young reach staggering numbers.
Horseshoe crabs breeding at night.
The huge population of horseshoe crabs on the bay is no accident. The bay almost seems built to suit the crabs. Crabs need beaches with large and deep sand flats, allowing just enough water to sufficiently oxygenate the eggs without drowning them. They need the sea floor to gently rise into breeding beaches, allowing easy access. While breeding, crabs have to eat small bivalves, which they find in abundance in the bay’s extensive intertidal and subtidal flats.
Horseshoe crab eggs.
The most important aspect of the bay is its quickly warming waters in the spring. On Delaware Bay, horseshoe crabs don’t breed until waters reach 59 degrees. You won’t see this temperature on the Atlantic Coast until June. Not so on Delaware Bay! Although the bay has deeper water, mostly in sloughs that snake under the surface out to its mouth at Cape May, most of the water is relatively shallow — usually less than 18 feet. That may sound deep, but keep in mind the Chesapeake has 100 feet water for most of its length and deeper water throughout. The shallow water of Delaware Bay allows it to heat up soon after the air temperature rises.
Unfortunately, it also cools down quickly and because of this the crab spawn has stopped. The bay’s water temperature went up dramatically in late March and April, so much so that we worried it might reach the critical 59 degree threshold in April long before the birds arrived in May. But then the warm weather stopped and the bay temperature dipped than rose, several times in fact. By early May, it had gotten just above the threshold, heating up to about 61 degrees at the Cape Henlopen marine buoy. We hoped for the best. Crabs started to breed in good numbers on a few beaches, like Reeds Beach, but were thin elsewhere. We had about 20,000 shorebird relying on the spawn and the eggs that were brought to the surface.
Than the bay cooled down again. A nasty western wind and cold front enveloped our area over the weekend and the cool weather followed. By Monday, the temperature went down again and the crab spawn stopped. This is bad.
When the spawn stopped the birds hovered up the remaining eggs in a few days. Then they started wandering to find eggs in odd places, under houses, along bulkheads. Some even went to areas like the oyster aquaculture racks to find eggs to the delight of the people trying to expand aquaculture. But what they saw was desperation.
Herring gull hunting red knot, Cooks Beach, New Jersey. Photo by Jack Mace.
Worse the Black Back and Herring Gull that feed on eggs and overturned crabs couldn’t find eggs and started eating shorebirds. By the end of Thursday (May 19) we found 8 dead red knots. These gulls can swallow small sanderling and semipalmated sandpipers like gum drops, so we really don’t know how many shorebirds died.
Herring gull hunting red knot, Cooks Beach, New Jersey. Photo by Jack Mace.
Relief might be in sight though. Thursday, Friday and today will be warmer. The bay’s temperature is back up over 60 degrees. Thursday night we had a fairly good spawn. Hopefully we will be back in business soon.
A Series of Updates on Year 20 of the Delaware Bay Shorebird Project
By: Dr. Larry Niles, LJ Niles Associates LLC
Our team trapped over 500 shorebirds over the weekend including several hundred red knots in two catches on May 12th and 14th! Most of the caught birds, knots, ruddy turnstones and sanderlings arrived in good condition, which is always a relief at this early stage in the season. Ruddy turnstones returned in better-than-average condition, weighing in at 5 grams higher than normal arrival weights.
Team banding ruddy turnstones on Reeds Beach.
The condition on arrival is an important focus of the project. In some years, knots struggled to get to the bay, coming in at average weights of 105 grams, 15 grams lighter than this year. One poor soul practically fell onto the beach with only 84 grams of weight, dangerously burning muscle to get here.
To really understand it best you must put yourself in the birds’ shoes (in a matter of speaking). We can do this because we have been attaching small tracking devices called geolocators on knots and turnstones for the last 5 years. Geolocators must be recovered to download the data, and we did this with a knot banded with the inscribed flag TVV in 2015. The map of that bird’s heroic journey can be seen below.
Delaware Bay, New Jersey, USA
Follow TVV’S path from Delaware Bay to its Arctic breeding area, then down to its Chilean wintering area, then back to Delaware Bay. It spent less than one month in the Arctic but over 6 months in its Tierra Del Fuego winter quarters. The rest of the time was spent flying or resting between flights. It’s flight from Southern Brazil to Delaware Bay was truly awe inspiring!
Imagine you are TVV and about to fly from balmy Brazil to Delaware Bay, 5,000 miles away. Most birds will leave near nightfall, when the weather is settled and usually when there tends to be a favorable wind. Once aloft you have no idea of the conditions you will face for the next 6 days. Some birds have an easy time of it, some get caught in opposing winds, others get blown off course and must struggle to return. This is the reason for the varying weights on arrival.
Red knot photo by Al Janerich.
So what did the birds find when they arrived this year? So far, the horseshoe crab spawn has gone well. It started early in the month, so that by the time birds like TVV arrived, they found a nice concentration of eggs for the taking on Delaware Bay beaches. At first, the birds poured into the bay. Last Thursday May 10th, we had about 1,000 knots on the New Jersey side of the bay. By Saturday, the number has grown to 8,000 knots – and our two catches proved they were gaining weight at a good clip.
All that changed on Sunday when a complicated cold front hit the bayshore. For two days we have had strong winds from the west, creating breaking waves on much of the New Jersey bayshore. The crab stopped spawning in most places. The winds blow as I write this blog and is certainly holding up birds from arriving, some may have stopped migrating others are fighting this merciless 30 mph wind.
Early morning on Pierce’s Point in a 30 knot wind from the west, blowing directly on shore and stopping all horseshoe crab breeding.
In our next post, learn how the winds affected the birds over the last few days.
