Conserve Wildlife Blog

Posts Tagged ‘mangrove forest’

Science in the Mangroves

Sunday, January 24th, 2016
Update from Brazil: “We are Going to Have to Science the ‘Heck’ Out of This”

by Dr. Larry Niles, LJ Niles Associates LLC

larger view of brazil

 

We came to Brazil to conduct a rigorous scientific study of the wintering population of shorebirds in a place where the land and sea act against any rigorous protocol. It would be easier to just go out and count birds and identify their habitats and prey, but our charge is more difficult.

 

The survey wraps around satellite imagery, strange unintelligible wavelength data coming from satellites hovering over the earth that can be transformed into brilliant and useful maps in the right hands. Those hands belong to Professor Rick Lathrop and his post doc Dan Merchant. Rick leads the Center for Remote Sensing at Rutgers and he and I have collaborated on projects ranging from municipal habitat conservation planning to Arctic red knot habitat mapping. He has created one of the most alarming maps that every person from New Jersey should know about.

nj_landchange450

The mapping of Reentrancias Maranhenses, an internationally recognized site of ecological importance is especially tricky. Our research platform is a 50-foot boat and we will be out of cell and internet contact for much of the time. Our method of collecting data for the mapping was devised by the whole team, but especially with the help Professor David Santos of the University of Maranhao, my colleague Dr. Joe Smith and Humphrey Sitters of the International Wader Study Group.

Our 50-foot catamaran

Our 50-foot catamaran

It focuses on collecting bird and habitat information using randomly selected survey points. In other words, we will try to pick places at random to survey so that when we combine them we will have a sample that represents the entire area, not just the places we surveyed. It’s like trying to figure how many different kinds of chocolates are in a valentine. If you take them all from one side then you might have sampled the chocolate covered cherry section leading to believe they are all one kind. But if you choose chocolates at random than you will find the box includes other kinds,  caramel or fruit or nutty chocolates. This is making me hungry, but you get the point.

 

The area  of our box we is very large, bigger than New Jersey, and it grows and shrinks every day with the tides. So, sampling is tricky business because a sample at low tide, when the tide is out exposing vast areas of intertidal mud and sand flat, is very different than when the tide is high. So we will be classifying habitat, or stratifying it, so we  can focus on limited survey time to get the best sample.

 

Once collected we can start making maps.  All data will be geo referenced – or located precisely  with GPS units – so it can be accurately mapped. With this, we will train the satellite maps to outline the habitat best for shorebirds.

 

All this while exploring areas that have received little scientific scrutiny and under tropical conditions, almost daily rain, a persistent 20 mph wind and summer heat.  Add parasites, mosquitoes and diseases like malaria and one can see this a rugged undertaking.

 

Our crew is up to it.  Besides those mentioned above Mark Peck from Royal Ontario Museum, Danielle Paluto from the Brazilian CEMAVE (a counterpart to our USFWS), Steve Gates a veteran of expedition on other SA trips, shorebird expert Dr. Mandy Dey, Stephanie Feigin from Conserve Wildlife Foundation of New Jersey and the author round out a dream team of bird study in difficult places.

Our crew banding shorebirds in Brazil in 2014.

Our crew banding shorebirds in Brazil in 2014.

 

Learn more:

 

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

 

 

CWF Biologists Travel to Brazil to Study Red Knots

Wednesday, January 20th, 2016
On our Expedition to Study Shorebirds along the Northern Coast of Brazil

By: Dr. Larry Niles, LJ Niles Associates LLC

Ana Paula with Red Knot

Ana Paula with Red Knot

The largest mangrove forest in the world covers the Brazilian coastline at the equator near the mouth of the Amazon river. The forest extends out into the Atlantic in long peninsulas tipped by wind swept and mostly inaccessible beaches. The forest, beaches and their long intertidal mud and sandy low tide flats support the largest wintering population of shorebirds in the hemisphere, perhaps the world. The red knot, a listed species in both North and South America, also uses this remote tropical coast.

Boat Trip Route

Boat Trip Route

Catamaran

Catamaran

 

 

 

With scientists from the U.S., Canada, England and Brazil, we will attempt a large scale mapping of this important habitat using state-of-the-art satellite mapping. We will do this from a 50-foot catamaran and two zodiacs hopping from one mangrove estuary to another and conducting bird surveys targeting key areas over a 150 mile-section of the coast. We will be the first to survey some areas. Our goal is to figure out the main threats to both bird and habitat.

 

 

To understand the importance of this area one has to think about it like a shorebird. Although born in the Arctic they actually spend only a few months there. They spend a few months moving from their nesting area to their wintering area. They spend the rest of their lives, the majority of their year in the wintering area. A threat to the wintering area would be grave.

 

Most of our survey zone is part of the Reentrancias Maranhenses, a protected area of the state of Maranhao, Brazil. Our catamaran captained by William Thomas will leave from a small town near the city of Sao Luis, Brazil. From there we will sail along the coastline moving in and out of the mangrove islands to survey shorebirds, habitat and marine invertebrates. We will “geo reference” all data, or take detailed coordinates so the data can be reproduced on satellite mapping.

Satellite Map

Satellite Map

 

Satellite maps aren’t really maps as most people understand — pictures or drawings of a section of the earth — they are digital files of remotely sensed data, they are only wavelengths of light that must be interpreted to represent actual habitat. We will train the satellite data so that each habitat will be represented by a combination of spectral data — colors in sense.

Environmental disturbance. Photo by Mark Peck.

Environmental disturbance. Photo by Mark Peck.

Once completed, we can relate the habitat maps with information on birds, their prey and equally important, the threats to the birds and prey. For example, shrimp farming is growing in this area. Entrepreneurs are stripping the intertidal zone of mangrove forest, diking the area and then growing shrimp. Once the area accumulates too much waste and chemicals, they abandon the site and move on to damage another mangrove forest. We will determine which areas are of importance to the birds and potential targets for shrimp farmers. But there is more: oil spills, disturbance from tourists, water pollution are among many.

 

Over the next three weeks, we will be reporting on our work on this blog.

Log of Red Knot DbY7 with geolocator.

Log of Red Knot DbY7 with geolocator.

 

Learn more:

 

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