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Posts Tagged ‘Delaware Bay shorebird conservation project’

2015 Delaware Bay Shorebird Project Continues!

Sunday, May 17th, 2015
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.

Climate Change is Threatening the Existence of the World’s Most Amazing Bird

Monday, December 15th, 2014

By: Lindsay McNamara, Communications Coordinator

The Rufa red knot (a shorebird) named "Moonbird," or "B95," photographed in a crowd of birds at Fortescue, NJ. Credit: Christophe Buidin.

The Rufa red knot (a shorebird) named “Moonbird,” or “B95,” photographed in a crowd of birds at Fortescue, NJ. Credit: Christophe Buidin.

“Moonbird is the most famous, charismatic member of a group of mid-sized shorebirds called Rufa red knots, whose numbers have plummeted so dramatically in the past several decades that they just became the first bird ever listed under the Endangered Species Act with climate change cited as a “primary threat.”

 

Rufa red knots are among the avian world’s most extreme long range flyers (especially in light of their relatively small size). They travel vast distances — some flying over 18,000 miles — in the course of an annual migration that begins in Tierra del Fuego, Argentina, and extends all the way up to the Canadian Arctic (and back again).

 

Which brings us to Moonbird’s distinction: Because he is so old — he is at least 21 — he is believed to have flown as many as 400,000 miles in his lifetime. The distance to the moon varies, depending on where it is in its orbit, but the average distance is about 237,000 miles. Thus, Moonbird has not only flown the distance it takes to reach the moon — he has also covered the bulk of the return voyage.

 

Assuming that Moonbird is still living — the last sighting was in May — there are reasons to wonder whether there will ever be another bird that is his equal. Why? Simply put, his subspecies has been devastated, and climate change will only make matters worse — making extreme survival of the sort that Moonbird has achieved that much more difficult.”

 

Washington Post Science and Environment Reporter Chris Mooney explores Moonbird’s journey, threats to the species, and the recent Endangered Species Act listing of the Rufa Red Knot:

 

Learn more:

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

 

Wildlife Beach Restoration Groups Applaud Endangered Species Act Designation for Red Knot

Thursday, December 11th, 2014
Shorebird now federally protected as threatened species under Endangered Species Act

By: Lindsay McNamara, Communications Coordinator

A red knot in breeding plumage along the Delaware Bay. © Bill Dalton

A red knot in breeding plumage along the Delaware Bay. © Bill Dalton

Wildlife conservation organizations leading the efforts to restore New Jersey’s Delaware Bay beaches for at-risk shorebirds today applauded the U.S. Fish and Wildlife Service decision to designate the Red Knot, a migratory shorebird, as “threatened” under the Endangered Species Act. A “threatened” designation means a species is at risk of becoming endangered throughout all or a significant portion of its range.

 

“This federal designation will make a big difference in strengthening the protections of this incredible shorebird,” said David Wheeler, Executive Director for Conserve Wildlife Foundation of New Jersey.

 

“Here in New Jersey, we are restoring the vital beach habitat that had been decimated by Hurricane Sandy, and this designation ensures the safeguards we are providing can be complemented along the East Coast,” Wheeler added.

 

Since the 1980’s, the Knot’s population has fallen by about 75 percent in some key areas. Wildlife biologists believe the major threat to the Red Knot is the dramatic decline of horseshoe crab eggs, an essential food source at the most critical stop over during their 8,000 mile trip from southern wintering grounds to Arctic breeding territory. High-energy horseshoe crab eggs provide nourishment for Red Knots to refuel and continue their journey.

 

“This is an important and needed step in the conservation and recovery of the Red Knot. It is an essential step in preventing the extinction of this amazing long distance traveler,” stated Tim Dillingham, Executive Director for American Littoral Society.

 

The largest concentration of Red Knots is found in May in the Delaware Bayshore of New Jersey and Delaware, where the shorebirds stop to gorge themselves on the eggs of spawning horseshoe crabs. In just a few days, the birds nearly double their weight to prepare for the final leg of their long journey.

 

“The major decline of horseshoe crabs in Delaware Bay is one of the largest threats to the survival of the shorebird,” explained Dr. Larry Niles, a biologist who leads the beach restoration efforts for Conserve Wildlife Foundation of New Jersey and American Littoral Society, and has studied Red Knots for three decades. “Agency groups have been working hard for the last two years, and will continue for the next two years going forward to rebuild the habitat damaged by Hurricane Sandy that the horseshoe crabs rely on. This work is integral to the recovery of the Red Knot and the shorebird’s best hope for survival.”

 

In the wake of Hurricane Sandy, American Littoral Society and Conserve Wildlife Foundation of New Jersey worked with the U.S. Fish and Wildlife Service, the New Jersey Division of Fish and Wildlife and the New Jersey Recovery Fund to remove 8,000 tons of debris and added 45,000 tons of sand to the beaches just before the annual spring arrival of the Red Knot in 2013.

 

Learn More:

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

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