An interview with Leandro Castello

Leandro Castello’s research program focuses on the ecology and conservation of fish and fisheries in relation to global change processes, with particular attention to tropical regions. Most of his research has been on Arapaima spp., one of the largest and most overexploited fishes of the Amazon Basin.  His research on arapaima has focused on the migration, reproduction, abundance, and population dynamics, as well as on the skills and knowledge of arapaima fishers.  These studies have led to the development of a successful model of community-based management, where fishers themselves assess arapaima populations to determine fishing quotas*. This model has been successfully replicated throughout the Amazon, in and outside Brazil.

Lorena Candice, one of the FEME members and a personal fan of Leandro’s, interviewed him about his research. She is personally happy for having had this chance and we are even happier for learning about his opinions.
 

FEME: After almost 20 years managing arapaima in the Mamiraua Sustainable Development Reserve, what is your evaluation of the expansion and evolution of the arapaima management throughout the Amazon, within and outside reserves, and within and outside Brazil?
LC: I think the result of that work has been outstanding.  We had not idea that it was going to work as well as it did, and that it was going to expand to almost 500 fishing communities throughout the Amazon.

Photo by Ricardo Oliveira

FEME: What are the main challenges faced by managers? How do you think such difficulties could be minimized?
LC:  I think there are several challenges.  Perhaps the biggest one is finding a way for stakeholders, including fishing communities, government agencies, and the various NGO personnel involved to better understand the bio-ecological basis and intricacies of the system.  Several basic requirements and features of the ecology of arapaima in the area are not yet properly taken into account, and that decreases the effectiveness of the system.  Another challenge is understanding the key factors that promote or impede local communities from complying with the management system’s rules.  Illegal fishing for instance is widespread and the communities need help overcoming the social and economic factors that prevent fishers from complying with management rules.

FEME: As cattle raising grows in the Amazon, so does deforestation. In one of your recent papers, you showed how deforestation affects fisheries, although this is hardly ever taken into account by managers, policy makers and even by the large NGOs. Why do you think such important question has not made into the agenda of these groups? Are the local human communities already feeling the impact of deforestation in their fisheries?
LC:  Overall, freshwater ecosystems of the Amazon have been at the sidelines of government, conservation, and scientific agencies, so those issues just don’t get the attention they deserve.  Local communities have always known that floodplain deforestation decreases fish available for harvesting, but policies to prevent further deforestation are either inappropriate or not enforced.

FEME: Perhaps a more popular threat, the kind that makes the news and get into the NGOs' agenda, regards the growing implementation of large hydroelectric dams in the Amazon. We've seen some very desperate pledges in the literature regarding the effects such dams have on fish, especially on migratory ones. Are we being too alarmist or not alarmist enough? Are people already feeling the consequences of such large dams?
LC:  It may be too early to tell.  We don’t really know.  Those dams certainly impact the environment and livelihoods, and one of two will not cause much harm.  But the real issue is that several large dams, plus thousands of small stream dams, will certainly cause major changes for which no one is ready to manage.  A great deal of research is needed before we can predict their impacts with a reasonable degree of certainty.  In the lack of further information, the more cautious we are, the safer future generations will be.

FEME: If we assume that we will follow the same pace we did so far regarding how we treat the Amazon, what should we expect to happen to Amazonian fisheries?
LC:  Their long-term demise as we now know them.  We’ll probably be eating tiny detritivore fish.
 

By Lorena Candice

 *most of this text was extracted from Leandro´s blog.

What you are doing the FEME group students?

Júlia Tovar Verba is PhD student of our research group at the Federal University of Rio Grande do Norte. In her thesis she is integrating fishers’ knowledge and scientific information, as well as genetic analysis to build distribution and abundance models for marine fishes of economic interest for Brazil. 

Currently, she is doing an internship the Conservation Genetics Lab, at Macquarie University (Australia) with Prof. Adam Stow. Her goal there is to apply Seascape Genetics analysis to identify important environmental drives for connectivity between populations of a snapper (Lutjanus jocu) and a parrotfish (Sparisoma axillare) in the entire Brazilian coast and between coastal and oceanic islands. 

Júlia Tovar Verba

This internship has been supported by the Endeavour Research Fellowships program of the Australian Government, National Geographic Society and CNPq.

We will see soon new interesting results about here project, meanwhile…

From: http://obiat.com.au/phd-thesis-writing/

Identifying feeding areas of the Fernando de Noronha seabirds

During the last two years we have been working together with the Oceanica NGO and researchers of the Institut de recherche pour le développement (IRD, France) and Universidade Federal de Pernambuco (UFPE, Brasil), in a project funded by the Fundação Grupo Boticário. The project took place in Fernando de Noronha (FN) archipelago with the main goal of identifying vulnerable ecological areas for seabirds of FN, which is an oasis of marine life in relatively barren open ocean. Indeed among others remarkable biological features, FN accommodates the largest concentration of tropical seabirds to be found in the Western Atlantic Ocean. FN is protected by two different categories of protected area, according to the Brazilian legistlation: an APA (environmental protection area) covering mainly terrestrial ecosystems since 1986 and a marine national park, covering 112.7 km² of the archipelago, since 1988. Since 2001, the APA and the core and buffer area of the national park were listed as World Heritage by UNESCO. During these years, Sophie Bertrand, responsible for the fieldwork activities, and her team collected data on red footed boobies (Sula sula), brown boobies (Sula leucogaster) and especially masked boobies (Sula dactylatra) species. 

Photo of Sula Sula individuals. By Sophie Bertrand

In particular, the team has tagged several individuals with GPS, dive and accelerometer recorders to understand feeding areas and marine behavior during critical periods. This requires capturing the same bird twice, once to deploy the equipment and a second time to recover the device and the data recorded. In addition, at each recapture, animals were measured and biologically sampled (including prey regurgitated). Those biological samples will be analysed by isotopic analyses for identifying their trophic niche (N and C isotopes) and for estimating global biocontamination (Hg isotopes).

Photo of the procedure of capture-recapture. By Sophie Bertrand

Among the top predators of the ecosystem, there is also the artisanal fishery of the archipelago. This is a small fleet (less than 10 units) that mainly fish with live bait (the 'sardinha' or the 'garapao' whose schools frequent the islands beaches). The fishers' catches consist mainly of barracudas, but also of some jacks, tuna and snappers. During the project two crew members boarded periodically with fishers to document main fishing grounds, fishing activities and catches. 

Photo of the fishery of FN. By Sophie Bertrand

By analyzing both the bird and the fishing data, we hope to better understand how the structuring of marine habitat conditions the behavior of seabirds, and how they are orienting and feeding in what appears at first glance as a big blue desert. This knowledge should also feed into a reflection on the relevance of different tools for their conservation.

For more information about the project take a look to the blog https://fnavesmarinhas.blogspot.com.es/

What you are doing the FEME group students?

Today we will talk about Natalia. Currently, she is doing a PhD thesis in Ecology at the Federal University of Rio Grande do Norte. Her thesis associates habitat preferences, demography and molecular tools aiming to assess the vulnerability of the endemic and endangered Greenbeak parrotfish (Scarus trispinosus), with the goal of subsidizing actions for the species conservation. Last year she worked very hard to collect data...take a look!

Aiming to investigate habitat preferences, underwater visual censuses were conducted along Rio Grande do Norte coast (Brazilian northeast) to collect density and biomass patterns of five endemic Brazilian parrotfish species. 

Endemic Brazilian parrotfish individuals.

The visual censuses consist of belt transects in which a diver identified, counted and estimated the total length of the parrotfish species inside an area of 40 m² (20 x 2 m). 

Natalia during a visual census.

Parrotfish biomass was estimated using length-weight relationships available in the literature. Following each visual census, a second diver ran the same belt transect taking one photo of the benthos every two meters, resulting in ten photos per transect. Each photograph was analyzed with the software photoQuad to investigate the benthic cover. 

Looking for reef features.

Other reef features (complexity, depth and coast distance) of each site are also considered. The data are being analyzed and the results will be shown soon. 

Thousands of scientists give a second notice to humanity

More than 15,000 scientists from 184 countries have published a second warning to humanity advising that we need to change our wicked ways to help the planet. Among them the FEME members signed this call.

This new message is an update of the original warning sent from the Union of Concerned Scientists 25 years ago. But today the picture is far worse than it was in 1992.

It's true that some progress had been made in some areas - such as cutting ozone-depleting chemicals, and increasing energy generated from renewable sources - but this was far outweighed by the damaging trends.

In the past 25 years:

• The amount of fresh water available per head of population worldwide has reduced by 26%.
• The number of ocean "dead zones" - places where little can live because of pollution and oxygen starvation - has increased by 75%.
• Nearly 300 million acres of forest have been lost, mostly to make way for agricultural land.
• Global carbon emissions and average temperatures have shown continued significant increases.
• Human population has risen by 35%.
• Collectively the number of mammals, reptiles, amphibians, birds and fish in the world has fallen by 29%.

Many of our current practices put at serious risk the future that we wish for human society and the plant and animal kingdoms, and may so alter the living world that it will be unable to sustain life in the manner that we know.

In this letter scientists give 13 suggestions for managing our impact on the planet, including establishing nature reserves, reducing food waste, developing green technologies and establishing economic incentives to shift patterns of consumption.

We can all do something every day to stop this negative trend. Take a look at the article here:

Ripple, W. J., et al., (2017). World Scientists’ Warning to Humanity: A Second Notice. BioScience.

Plastic nanoparticles cause brain damage in fish

A study conducted at the University of Lund (Sweden) revealed that plastic nanoparticles reduce the survival of zooplankton and penetrate the fish brain, causing behavioral disturbances. This pioneering study was published in the journal Scientific Reports, last month.

The increase in the production of plastic material in the last decades around the world has turned plastic waste into a major problem in the oceans. About 60-80% of all marine litter is made out of plastic, affecting at least 660 marine species (the ones we know so far), showing that this material is a serious pollutant for aquatic environments. Through physical-chemical and biological reactions caused by environmental conditions, the plastic material is divided into smaller and smaller pieces, reaching the size of nanoparticles. Being so small is a dangerous characteristic because the plastic nanoparticles are able to overcome biological barriers, penetrating tissues and accumulating in organs, thus affecting the behavior and the metabolism of the organisms.

One of the things this study shows is how plastic nanoparticles strongly affect an aquatic food chain from the zooplankton Daphnia magna to the top consumer, the freshwater fish, Crucian carp (Carassius carassius), which is a species common in anthropogenically affected waters. The researchers showed that amino-modified polystyrene nanoparticles were transferred through a three-level food chain, algae-zooplankton-fish, directly affecting the brain of these fish, modifying their behavior in terms of activity, feeding time and distance they need to swim to consume the food provided.

IStock Photo.

The authors suggests that the effects caused by plastic nanoparticles to the biota depends on both concentration and size of particles, therefore they specifically appeal to plastic manufacturers to adjust the nanoparticles production to sizes that are less dangerous for the metabolism of organisms, so that from a wider perspective, the top consumers, humans, will not come to be affected by their own garbage.

By Thiago Guerra

Literature cited:

Mattsson et al. Brain damage and behavioural disorders in fish induced by plastic nanoparticles delivered through the food chain. Scientific Reports 7:11452.