Conserve Wildlife Blog

Posts Tagged ‘Semipalmated Sandpipers’

In Dangerous Territory on the Delaware Bay

Wednesday, May 24th, 2017

By Dr. Larry Niles, LJ Niles Associates, LLC

Four days ago, the shorebirds of Delaware Bay could look forward to a bright future. But in the last week their chances for survival and good production have diminished. In fact, they are as dismal as the cold drizzle pockmarking the murky water in front of our house on Reeds Beach.

The following two graphs tell the story. We captured red knots on May 12 and 16 that showed a normal, although not spectacular progression. Then we made a catch of knots on the 19th and again today on the 23rd, and in total they gained only 2 grams of fat per day. With an average weight of 144 grams at this late date and only 7 days to go before they must leave for the Arctic, their future looks bleak. If current conditions hold, the knots will suffer their worst year in 14 years. Turnstones fared no better gaining less than a gram per day on average.

The graph plots all the average weights of all the catches of red knot our team has made since 1997. The average weight of our catch on May 23 suggests trouble is brewing for these birds.

 

The graph plots all the average weights of all the catches of ruddy turnstones our team has made since 1997. The average weight of our catch on May 22 suggest trouble for both species.

So why this dismal report? Several factors are at work that were covered in my last post. The water temperature of the bay has only just exceeded the threshold for horseshoe crabs to start breeding in earnest. But the nights are cold and the water temperature remains cold. Last night was the first good crab spawn since the birds arrived and it was lackluster. Although there is some spawning in the creek mouth shoals and the lower beaches near Norburys Landing and Villas, our most productive beaches remain nearly devoid of crabs and crab eggs.

The second problem is still a mystery. At this stage only about half of the red knots have found their way into the bay. Weather patterns in the southern US could have been blocking migration for the last 5 days because adverse winds, poor visibility and rain impedes birds progress and could stop northward movement. The conditions have finally let up, so it possible a new cohort of birds might arrive any day. If so they will face a true food fight with many birds already here and desperate for eggs.

Laughing Gulls, Red Knots, Ruddy Turnstones, Sanderlings and Semipalmated Sandpipers struggle to find horseshoe crab eggs on the shoals of South Reeds Creek. Eggs are scarce because cool water temperatures prevent crab spawning.

However, it may not be the adverse weather but choice that is keeping the population down. Today we learned of a red knot banded on May 16 this year by our counterparts in Delaware that was resighted in Cape Cod by Mark Faherty, the senior scientist for Massachusetts Audubon in Cape Cod. In other words, red knots and other shorebirds are coming to the bay finding too little food or too much competition for the food now available and choose to move on. This is very possible for the short distance migrants because they arrive earlier and have less weight to gain before leaving for the Arctic. Knots wintering in Tierra del Fuego, arrive later and in much worse condition, often times lose muscle mass to get here. They cannot recover that loss and still gain an extra 80 grams on their normal diet of mussels and clams.

We tried to test this second possibility today (May 23) after our red knot catch this morning. Humphrey Sitters, Amanda Dey and I surveyed the intertidal mud flats of the Atlantic Coast from Cape May to Stone Harbor looking closely at the mussel beds. We know that every year red knots, especially short distance birds, use mussels and to some extent clams, rather than come to the bay and feast on horseshoe crab eggs – simply because they can. We found 1700 knots, so it possible even more are spread out further up and down the coast.

In the end, it may turn out to be both explanations. The short distance knots are using the Atlantic Coast and the long-distance birds have yet to arrive. One should remember that the knot is federally listed in both Canada and the US primarily because of the dramatic declines in the long-distance winters. There is still a small window for a successful outcome. The next few days will tell the full story.

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


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A Resilient Shoreline in Stone Harbor for Birds and People

Thursday, April 2nd, 2015
Conservation Partners Collaborate to Improve Beach Habitat for Birds and Provide Flood Protection for Stone Harbor Residents

By: Lindsay McNamara, Communications Coordinator

Oystercatchers © Dr. Larry Niles

Oystercatchers © Dr. Larry Niles

Beach nesting birds and New Jerseyans who live along the coast both depend on a resilient shoreline — and plenty of sand.

 

This season, thanks to a grant from the National Fish and Wildlife Foundation (through their Hurricane Sandy Coastal Resiliency Grants Program), a team led by New Jersey Audubon worked with Conserve Wildlife Foundation of New Jersey, The Wetlands Institute, New Jersey Division of Environmental Protection, and the US Fish and Wildlife Service to make the beach community of Stone Harbor Point more resilient for birds and people alike.

 

Conserve Wildlife Foundation of New Jersey collaborated with New Jersey Audubon to improve beach habitat for Piping Plovers (endangered in New Jersey), American Oystercatchers and the colonially nesting Least Terns and Black Skimmers. Sand from the southernmost tip of the point was moved to create three areas of higher elevation. The new landscape is expected to benefit Red Knots, Semipalmated Sandpipers, Sanderlings, Semipalmated Plovers, Black-bellied Plovers and others.

 

Stone Harbor, a small beach town along the New Jersey shoreline will see added coastal resiliency benefits and flood protection due to this innovative project that combined the needs for shorebirds with the needs for shore residents. The Stone Harbor project also included the construction of a wide berm of sand near the beachfront parking lot at the far south end of the town. This aspect of the projects aims to increase flood protection for the residents on the developed area of the island.

 

Learn more about this project on New Jersey Audubon’s blog and in the ShoreNewsToday.com article “Working for the Birds.”

 

The National Fish and Wildlife Foundation (NFWF) is a non-profit organization created by Congress to preserve and restore our nation’s native wildlife species and habitats. NFWF is one of the largest funders of wildlife conservation in the world. They fund science-based projects and community-driven solutions.

 

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