Conserve Wildlife Blog

Posts Tagged ‘migratory shorebirds’

Early days on Delaware Bay – Horseshoe Crabs Just Beginning To Breed as Shorebirds Arrive

Saturday, May 19th, 2018

by Larry Niles

Horseshoe Crabs Just Beginning To Breed as Shorebirds Arrive

 

Delaware Bay horseshoe crab eggs reach sufficient levels to give red knots and other shorebirds a good start on the fat they need to fuel the last leg of their yearly journey in the first week of the stopover ( May 12-19).  Knots need at least 180 grams to fly to the Arctic and breed successfully.  This week we caught birds that weighed 93 grams which is 30 grams below fat-free weight.  These birds had just arrived from a long flight, probably from Tierra del Fuego, Chile or Maranhão, Brazil.  In the same catch, we weighed red knots as high as 176 grams or only 5 grams from the 180-gram threshold.  These birds are probably from Florida or the Caribbean wintering areas and so arrive earlier,  resulting in them having more time to gain weight.  All together it looks like a normal early migration and a modest horseshoe crab spawn, just barely enough for the birds in the bay.

shorebirds in a net

Our team prepares a catch of knots turnstones and semipalmated sandpipers for extraction to keeping cages. The birds will be covered to prevent feather abrasion before extraction (Photo by Stephanie Feigin)

However, we are still short of about half the population.  Our bay wide count won’t take place until next week on May 22 and 26. At this point it looks like we have about 14,000 knots in the bay, of which 8,000 are in New Jersey. In the last 5 years we have had a bay wide population of about 24,000 red knots.  The situation is similar for ruddy turnstones and sanderlings.  The southernly winds of the next few days will almost certainly bring in the rest of the flock by mid-week.

The Stopover Habitat is Growing

 

The condition of the stopover is mixed.

The work of Niles & Smith Conservation Services, Conserve Wildlife Foundation of NJ, and American Littoral Society continues to supply high-quality habitat for horseshoe crabs. We have developed an efficient system for maintaining the essential requirements of a good spawning beach, deep and large grain sand with berm heights that prevent over washing in a way that keeps cost down. First, by creating low oyster reefs to break waves in lower tides, thus protecting beaches from wind waves at low and mid tides.  Second, by placing sand on beaches that typically erode fast losing sands to adjacent creek inlets and the next beach south.  This way we can use one restoration to restore three different places.  For example, Cooks Beach loses sand to South Reeds.

 

restored beach in Delaware Bay

Thompsons beach before and after restoration by American Littoral Society and partners. (Photo by Larry Niles)

Oddly these successes may be contributing to the next big problem for the birds. The state of Delaware has been carrying out much larger scale beach replenishment projects that have added significant new sandy beach for crabs spawning.  At the same time the Atlantic States Marine Fish Commission has failed to deliver on its promise to increase the number of crabs.  The population is still 1/3 below carrying capacity or the number that existed 20 years ago.  The same number of crab divided by more beach equals decreasing crab densities.  Decreasing densities means fewer eggs reaching the surface because crabs are not digging up existing eggs to lay their own.

In other words, we need more crabs.

The Industry Finds New Ways around the ARM Quota

 

But the resource agencies seem perfectly happy to keep killing adult crabs for both bait and bleeding at near historically high numbers. Bait harvests recorded as coming from the bay have stayed the same, however other states such as NY are still taking and landing large numbers of crabs despite having no known crab historic population of their own. Additionally, Virginia states that a crab population still exists in the state, even though most field biologists consider them lost.  The truth is they are very likely taking Delaware Bay crabs and landing them as their own.

The Conservation groups are no longer satisfied with this loose regulation and are calling for regulations similar to those used for Striped Bass.  The Delaware Bay harvest should be restricted to just the quota agreed upon by everyone through the Adaptive Resource Management system.  All other landed crabs should be genetically linked to a source population, and if they do in fact come from Delaware Bay they should be taken out of the ARM quota. No one should be allowed to get away with killing our crabs outside the quota.

Or just stop the senseless killing of these valuable animals as bait for the dying couch fishery.

 

crab eggs graph on Delaware Bay

This graph compares the finding of Botton et al 1994 from horsesoe crab egg surveys done in 1990 and recent counts done in 2017

 

The same goes for the killing of crabs by the companies bleeding crabs.  The industry makes untold millions (the numbers are hidden from the public) but does virtually nothing to conserve the crabs while killing thousands. Their own estimate is well over 65,000 a year, but independent estimates double that.  This killing could also stop because a new synthetic lysate is available and can be used now, potentially cutting the need for natural lysate by 90%.

An Ecosystem Collapse and the Need for More Crabs

 

Why kill such a valuable animal?  It all started because the fishing industries saw little value and figured why not destroy the population until they are no longer economically viable.  Its called economic extinction and sadly it’s a tradition amongst Delaware Bay fishers still carried out this to this day on eels, conch, and other species.  But they didn’t know back in the early 90’s they would wrecking the entire ecosystem.

In 1991, we counted an average of 80,000 horseshoe crabs/meter squared.  Now we count 8,000.  Then the eggs stayed at that level for all of May and June then hatched young at similar densities. In other words, the horseshoe crab was a keystone producer of an abundant resource that maintained the bay ecosystem.  It was not just chance that at the same time the bay has one of the most productive weakfish and blue claw crab fisheries in the Atlantic coast.  Fish populations blossomed with the flush of horseshoe crab eggs and hatched young each year.

Now we must bring it back.  For the birds, for the fish, and for the people who love to bird and fish.

 

storm delaware bay horseshoe crabs

A storm looms over Delaware Bay. The last 4 days have been rain, some intense and cold. The water temperature needs to be 59 degrees or so for Crabs to spawn. On Saturday the 19th the water temperature fell below and the spawn virtually stopped in many places. It should resume with the warmer temperatures of Saturday and Sunday.

We are grateful to the National Fish and Wildlife Foundation and other donors who make this project possible.

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

Red knot numbers down in wintering grounds

Monday, February 26th, 2018

The Press of Atlantic City covered the troubling findings of Conserve Wildlife Foundation’s recent expedition to Tierra del Fuego in Chile to survey wintering red knots.

The numbers of red knots – an endangered migratory shorebird that spends every May along New Jersey’s Delaware Bay coast feasting on horseshoe crab eggs – declined by more than 20 percent between the team’s counts last year and this year.

Click here for the full story.

Piping Plovers in the Bahamas

Monday, January 29th, 2018

Our Work isn’t Done – the Ongoing Importance of Band Resighting

 By Todd Pover, Senior Wildlife Biologist

Earlier in January, I attended the Abaco Science Alliance Conference to make a presentation about recent conservation and research developments for piping plovers in the Bahamas. This marks the eighth year, starting in 2011, either solo or with CWF staff and other colleagues, that I have been able to follow piping plovers to their wintering grounds in the Bahamas to conduct work to better understand and help recover this at-risk species. And in another sense, to be an international ambassador for piping plovers.

Todd Pover, CWF Senior Biologist, busy searching for piping plovers on the flats in the Bahamas

Over that time, the focus of those trips has varied widely, including conducting surveys for the International Piping Plover Census in 2011 and 2016, improving our understanding of how piping plovers use the various habitats, engaging students with our Shorebird Sister School Network from 2014-17, helping Friends of the Environment, our primary partner there, integrate piping plovers into their educational/school programs, building conservation partnerships, and even producing a video. Tremendous positive changes have occurred in that time with regard to awareness of and attitudes towards piping plovers in the Bahamas and some significant conservation progress has been made, most notably the establishment of several new national parks by the Bahamian government that help protect piping plovers and other shorebirds.

(more…)

Shorebird Expedition Brazil: The rights of traditional communities

Monday, February 27th, 2017

By Larry Niles, LJ Niles Associates LLC

Over the last few days of our expedition, we left the state of Para and flew to Sao Luis in the adjacent state of Maranhao. There we began the next phase of our work, trapping red knots, ruddy turnstones and other species, as we have done since 2014.

 

 

But prior to leaving Para, while we stayed in the village of Apiu Salvatore, the fishermen asked to meet with Max. He hadn’t planned it, so at first, the reason was unknown. The fishermen of the village knew Max represented ICMBio, and that Apiu Salvatore fell within Resex Gurupi-Piria, one of the Brazilian agency’s many extractive or Resex reserves. As I described in the previous post, ICMBio conserves natural resources in each reserve for the benefit of traditional communities, such as this one. So Max had a good idea what the community had on their mind.

 

David and Danielle prepare for the meeting with the fishermen of Apiu Salvadori.

 

We entered the large open meeting space under a thatch roof with a good breeze cooled by a sudden evening downpour. The association leader, Antonio, got down to business. He explained the problem of immense ships lurking offshore, spreading giant purse seines or immense lines of baited hooks, and stealing all the fish. It threatened their own lives, not only their livelihoods but their very existence. One could see very clearly how vital fish were to these fishermen. The community consumed virtually no goods; most of their daily needs came from the sea or their backyards. Chickens, pigs, even lambs filled backyards.  Fruit like mangos and avocados literally fell from the trees. I saw no washing machines, microwaves, coffeemakers, or nearly any of the appliances that litter a typical U.S. kitchen.

 

There was one modern device found in every hut and cabin, no matter how small or dilapidated. All had TVs.  How, I imagine, can they fit in this primitive world while gapping at the lives of the rich and famous? These were not people ignorant of the world, but unfortunately, they could be innocent as lambs when faced with the greedy schemers and politicians of Brazil. And as the ongoing corruption scandals here evolve, it seems like nearly every politician serves their own or other greedy interests.

 

So it is understandable that the fishermen’s first thought was to go to the Catholic Church. But then we came. So they asked for Max’s advice.

 

The people of the village live simply with no luxuries except TVs. The town, located on a small island has no electricity except when the community generator is turned on at night. (Photo by C. Buiden.)

He quickly determined the fisherman had no idea they had legal rights to the fishery. He patiently explained the concept of ICMBio reserve system, the system of which they are a part. In theory, they could unify and certify their observations, take it to a judge and get a decision that would force the government to stop the theft by the international fishing fleet, at least in principle. Max and Danielle explained these rights and the group seemed sufficiently inspired. At least they left happy.

 

Why did they not know their rights? Max explained to me that the reserve manager for this area covered 60 other villages and that ICMBio has suffered 3 years of budget cuts. He reminded me how long it took to get to this village. So it’s the usual story familiar to U.S. agency biologists.  Here, as it is in rural U.S., but with a more obvious impact, starving good government often only starves the people who live on the land, the land itself and the wildlife, who depend upon it.

 

For me, it meant something more. We proposed this project to create better protection for shorebirds. We took the usual approach. First, do the surveys then will create scientifically defensible descriptions of the habitat’s value.  Finally, we overlay the threats: shrimp farming, oil spills, human disturbance, predators etc. then develop counter-measures.

 

I learned that nigh there is only one threat in this, one of the most important shorebird habitats in the world. It looms large above all others – if you erode ICMBio’s system of protection all the other threats will grow and decimate the fragile ecology of the area. Grow the ICMbio system and the traditional communities will enforce their legal right to conserve. They can monitor the threats and work with the agency to stop them. The laws already exist. The monitoring system is already in place. But this meeting pointed out they need more help.

 

Photos by C. Buiden.

 


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


 

Shorebird Expedition Brazil: Trapping shorebirds in Panaquatira

Saturday, February 25th, 2017

By Larry Niles, LJ Niles Associates LLC

The capture of Arctic nesting shorebirds first brought us to Brazil in 2013.  We brought 125 geolocators and caught both ruddy turnstones and red knots, attaching 85 on the former and 30 on the latter.  But we also came to create a new perspective on shorebirds in this place, one of the most important shorebird habitats in the world.

 

For all intents and purposes, shorebird work in this area started in the mid 1980’s, when Canadian biologists, Guy Morrison and Ken Ross surveyed from an airplane, the entire coast of South America.  In this monumental and dangerous survey they established an invaluable historic baseline of the number of Arctic nesting shorebirds wintering in South America. This was before shorebirds caught the interest of the public, and way before foundations and agencies devoted significant funding or staff time.  They surveyed the entire continent, but on the coast of Maranhao and Para they found the motherlode of shorebirds.  They did not, however, get close and personal.

Guy Morrison and Ken Ross about to conduct an aerial survey (also in the photo is Guy’s daughter Clair, Brad Winn, Jorge Jordan and Luis Venegas).

That challenge belonged to a team led by the late Allan Baker of the Royal Ontario Museum and Ines Serrano, then with CEMAVE, the Brazilian counterpart of USGS.  They also flew the coast but followed up with a ground survey and the capture of a small group of red knots. Along with Guy and Ken, their work cemented the hemispheric importance of this area.

Juliana holds one of the two birds caught in our second day of trapping. (Photo by C. Buiden)

Over the last 4 years we captured knots, turnstones, sanderlings, whimbrels, collared plovers, semi-palmated sandpipers, semi-palmated plovers as well as South American terns and other species. Last year we recaptured 20 geolocators in a catch of over a hundred ruddy turnstones.  But only in 2013 were we able to catch red knots. Although abundant in the region, populations are estimated at 10 to 15K, they are remote and elusive.

 

So we were happy to find on our first day of surveillance this year over 400 red knots. They roosted within a flock of about 1000 shorebirds located at the west end of a small working class beach resort called Panaquatira, about an hour out of Sao Luis. The flock including black bellied plovers, semi-palmated sandpipers and plovers, collared plovers, South American terns, Black Skimmers and a few whimbrels. We readied that night for an early morning attempt.

 

First we needed to figure out the tide. It rises and falls 13 feet in northern Brazil, twice that in Delaware Bay. The spring tide or full and new moon tide increases the range to 18 feet.  Consequently, the high tide line moves every day and catching birds with a cannon net depends on placing the net near the predicted tide line, because birds move with it to stay as far from the dangers lurking on dry land. Wind speed and direction changes the high tide line, and so does barometric pressure.

 

So much rides on where we place the net. On our first two attempts, we missed by just a few yards, but it could have been a mile. The birds moved with the tide and stood just outside the 30 by 100-foot area within which the birds must be to be caught. We tried moving them but they spooked and most gradually left the area altogether. Ultimately, we fired but caught only two knots and two whimbrels.

 

We were blessed on the third day. We arrived near dawn, over four hours before high tide so we had plenty of time to measure elevations. We knew the morning’s high would be about four inches lower than the previous night’s high, which snaked along the sandy peninsula used by the birds to roost. Standing on the tide line we used a method borrowed from Clive Minton to determine the location on the beach four inches lower.

 

Laying my head flat on the sand I trained my eye towards the horizon. This establishes a level line. Using her hand, Stephanie marks four inches on her leg than moves until the four inch mark lines up with the level line. Her location depends on the slope of the beach. In this way we determined the location of the tide line four hours hence. We dug in the net.

Larry Niles and Mandy Dey take training on measuring elevation from Clive Minton in Australia.

At about an hour before high tide, shorebirds started crowding into the area around the net. At first, oystercatchers, black bellies, short-billed dowitchers and a small flock of skimmers. Most of the knots hung back on an adjacent sand bar. With a little push, they too piled in right into the catch area.

 

We fired and caught 175 knots, 30 sanderlings, 20 short-billed dowitchers and 5 black-bellied plovers. Among the knots were 3 with geolocators. We flagged, banded and measured 145 birds, all the while releasing unprocessed birds that appeared stressed by the heat. By late afternoon we were back at the house cracking open beers. We completed all our objectives with one day to spare.

CWF Biologist Stephanie Feigin moves birds closer to the net. (Photo by Yann Rochepault.)

 

Stephanie and Julianna begin taking birds out of the cannon net. (Photo by Yann Rochepault)

 

We must cover birds with a light shade cloth to calm birds while they are extracted and placed into keeping cages. (Photo by Yann Rochepault.)

 

Processing our catch. (Photo by Yann Rochepault.)

 

One of the many values of catching shorebirds is examining their condition and molt. Here we compare two knots, an adult on the right and a second year or sub adult on the left. The latter molts its flight feathers much earlier than adults and it shows in the fading to brown. (Photo by C. Buiden).

 

Our team includes Carla Meneguin, Paulo Siqueira, Ana Paula Sousa, Larry Niles, Juliana Almeida, Carmem Fedrizzi Joe Smith, Stephanie Feigin, Yann Rochepault, Laura Reis and Christophe Buiden. (Photo by Juliana Almeida).

 

A red knot after banding and processing. (Photo by Y. Rochepault).

 


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


 

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