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Posts Tagged ‘2017’

Studying the Ridgway’s Osprey of Belize: Part II

Tuesday, March 14th, 2017
Flat calm Caribbean and three young Ridgway’s!

by Ben Wurst, Habitat Program Manager


The flat calm beauty of the Caribbean sea.

February 18: Second Survey of nests surrounding Placencia

Our second survey began from Placencia, a small beach resort town on the southern coast of Belize, which is a beautiful place to visit if you’re planning a trip to Belize. It was flat calm that morning, which made for great boating, but it was extremely hot! Life in the tropics was finally setting in… We headed towards the first nest location, which was last surveyed in 2016 by Paul and his team. Paul and Alan have been surveying osprey nests in Belize since 2014, so all known nests have been mapped and surveyed over the past couple years. Through the continued surveys of these nests we should be able to determine if the low productivity of Ridgway’s (around .3-.4 young/active nest) can sustain the population in Belize (the southern most nesting colony of Ridgway’s throughout their range). The work performed as a part of these surveys is critical to their long term survival in Belize. The first nest we visited was very unkept; however a pair was present. This ended up being quite the common sight during this survey.

An unkept nest south of Lark Caye.

An adult female Ridgway’s osprey in flight.

Red mangroves growing in the Caribbean off Placencia.

We then motored to several other small Cayes and surveyed a total of eight nests (only two produced young, photos below). Many were abandoned so it was hard for us to determine their overall fate. Many (good looking) nests Paul thought had failed (once had young or eggs and were lost) since the nests did look like they have been used this year but there were no birds around during our survey. Generally it is hard to determine overall nest success unless you watch a nest throughout the entire nesting season, or find evidence of nest failure when visiting a nest. In New Jersey, I generally can tell when a nest fails or hasn’t by observing the behavior of the adults. If a nest is active (bird present) and it is defending its nest with no young or eggs then it failed. If the nest is active (bird present) and it flies away with no defense of nest/young, then I call that nest active and housekeeping (a term for a bird that starts a nest but does not produce any eggs/young). Lastly, a nest with no birds = not active. Either way – it is very difficult to determine the overall nest success with only one visit/nest/season. If I were to go back to Belize then I would go twice during the nesting season there, which runs from December – March/April (once when birds are incubating and once when they have young). 🙂

Kept or Unkept nest?? You decide.

While we try to determine the cause of failure to an active nest, we think about potential threats to nesting ospreys. A substantial threat to ospreys in coastal Belize should be no surprise to us in New Jersey. Coastal development was a huge contributor to the decline of ospreys throughout coastal New Jersey. In Belize, there are many resorts on the coastal Cayes and the desire for more. Could this be the beginning of the decline of ospreys in Belize?? I hope not, as humans and ospreys can live alongside each other in very close proximity. To develop a Caye, mangroves are first cleared and then sand/coral is dredged onto the island to “fill” it in. Raising the elevation of the island allows buildings to be built and lovely white sand beaches to be manufactured for the enjoyment of humans (and sand flies!). During our survey we saw this in plain view. A nest on Long Coco Caye was still present in a large mangrove tree, however a huge pile of fill dredged into a pile right next to the nest. If this happened during the nesting season then there is no doubt that this nest failed…but, where were the adults?? The more we think about this work and the ospreys of Belize, the more concern we have for their overall safety and stability of their population.

A looming threat to Ridgway’s ospreys is development of coastal Cayes.

While scanning shorelines brown pelicans were a common sight around Placencia.

Kept or Unkept house on a coastal caye? You decide.

Sadly, evidence of humans is all over Belize. Welcome to the anthropocene.

The beauty of a disappearing horizon in coastal Belize. 

A brown pelican thermoregulating atop a red mangrove.

We kept moving along with our survey and ventured outside of the previous survey route to check a small Caye for a nest. Success! We found a nice nest atop a huge almond tree on Moho Caye. Bonus! There were also two large young (5-6 week old young) making this our first productive nest of the day! The island was private and occupied by a friendly caretaker. We talked to him about the ospreys, and he was happy to share the island with them. This just goes to show that ospreys and humans can coexist on the coast of Belize.

Can you spot the nest? 

No need to climb this nest. We wouldn’t be able to anyway. Next week we might bring a small drone to help survey tall nests like this one.

Two young visible along with an adult and loads of plastic bags. 🙁

The guardian. We were glad to see humans and ospreys getting along just fine on Moho Caye and hope to see this in the future too.

We continued to head north and back to Sittee River. Navigating along the edges of the mangrove islands would not have been possible with our experienced captain and his mate, Steve. They really made every survey go extremely smooth. Having boated for the majority of my life, I can attest to the fact that anything can go wrong at any time. You definitely do not want to get into trouble when boating offshore in Belize! There is few other boaters who could offer help, no patrolling of Coast Guard boats, no SeaTow/Boat US, and many islands are totally undeveloped and without freshwater. We are lucky to have had such a great crew to be able to get to us to where we needed to go and then back safely!

Navigating through tiny mangrove islands in search of nesting ospreys!

First mate Steve keeps an eye out while approaching the edge of a Caye.

Our experienced guide and captain Horace.

Guiding Horace through a cut along the edge of a Caye.

Fishing resort.

Siesta time!

Osprey siesta time!

The last nest we surveyed on our way back to Sittee River was one on Channel Caye. This nest was remarkable. It was built in a large dead mangrove and had two visible young. After closer inspection with my camera, we believed that their could be three young, so we decided to climb up and use a mirror to get a view into the nest. Jay T. eagerly climbed the short tree and saw three young. The female took off from the nest as the young played dead, as they do in New Jersey. She was not as upset as our ospreys get (Ridgway’s are less disturbed than NJ’s ospreys and hence less aggressive, IMO) and flew over the nest several times and then perched on a nearby branch, which allowed me to get some great photos of her. We were only by the nest for a couple minutes and quickly departed to let her return to the nest. This was the first time that Paul has ever seen three young in a Ridgway’s nest, so very cool for us to see and document! We surely hoped that all three survived to fledge. Usually by the time they reached the age that they were (around 3-4 weeks), then their chances of surviving were much more likely.

All things considered, there are many concerning threats to ospreys in Belize: nest abandonment, coastal development, plastic marine debris, possible persecution?, and the combined threats from the effects of climate change but we can only hope that from our work we can help improve their chances of surviving.

Stay tuned for Part III where we cover the next two surveys out and back from Turneffe Atoll and Calabash Caye!

Channel Caye female perched on her nest.

Jay peers into the nest.

Female looks on as we exit the area.

The third and elusive nesting!

A cut through to Sittee River.

Sunset on Sittee River.

Studying Ridgway’s Osprey of Belize: Part I

Friday, March 10th, 2017
CWF contributes to conservation of Belizean ospreys

by Ben Wurst, Habitat Program Manager

A male Ridgway’s osprey perched near its nest on a snag off Blue Ground Caye. Photo by Ben Wurst

When I first learned of the work being done by Dr. Paul Spitzer and Alan Poole to study the breeding population of Ridgway’s ospreys (Pandion haliaetus ridgwayi) in Belize, I was instantly captivated. I first met Paul at the Raptor Research Foundation Conference in Cape May last October where he explained the study and the need for partners to assist with this years survey. Some of the aspects that immediately drew my attention was the fact that the estimated size of the population there was around 50 pairs, that those pairs nest exclusively on the coastal cayes (mangrove islands), and that their estimated productivity rate was around .3-.4 young/active nest. The coast of Belize is approximately 170 miles long and protected by barrier reefs and these mangrove islands. (more…)

Photo from the Field: Ridgway’s osprey

Thursday, March 2nd, 2017
Back from Belize and summarizing results from our study of the Ridgway’s osprey

by Ben Wurst, Habitat Program Manager

Ridgway’s ospreys (Pandion haliaetus ridgwayi) are lighter than their north american counterparts. With a pale eye stripe and lighter plumage on their wings and back, they appear “white-washed” in appearance. Photo by Ben Wurst.

Stay tuned for a series of blog posts (with plenty of photos) from our work with ospreys in Belize.

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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