Tag Archives: Human

A new challenge

White-handed Tree Frog Leaps Toward LIfe's Challenges © Hudson Garcia, Brazil, Finalist, Nature & Wildlife, Sony World Photography Awards

A few years ago, Sharon Baruch-Mordo posted a provocative challenge. She called it the biodiversity challenge and offered it as an opportunity to write about the importance of your research in the context of biodiversity and conservation. The biodiversity challenge was a tough one. Not many graduate students are given training in science communication, and when we are, it’s usually targeted towards generating concise scientific prose that can be published in peer-reviewed journals. But the challenge is an important one. If we want to disseminate our knowledge, we have to be able to communicate it effectively. Well, you rose up to the challenge, and we were amazed by the quality and breadth of the results.

Today, BioDiverse Perspectives is emerging from a months-long torpor to issue a new challenge. We still want you to tell us what makes your research topic relevant. But we want you to evaluate the importance of your research from a different angle. What would happen if the thing you study were to disappear off of the face of the earth tomorrow? How would the world change if your research topic simply ceased to exist?

Tomorrow, your favorite focal biological unit of research (molecule, gene, organelle, organ, organism, ecosystem, general law of nature) will be deleted from the face of the earth. What are the implications?

We took the challenge. Next week we’ll be posting our results, and we challenge you to join in, too. You can upload your posts here. We will publish them all, in full, as we receive them, unedited, in all their glory.

May 9, 2016

Degrading Forests and Extinction Debts

Fragmentation of the Atlantic Forest of Brazil - one of the most fragmented habitats on Earth. Photo credit: "Atlantic Forest SPOT 1233" by Cnes - Spot Image - Wikimedia Commons

When I ask my introductory biology or ecology students what they think the biggest threat to Earth’s biodiversity is, climate change or pollution typically get the most votes. Perhaps the (much warranted) public attention and debate on these issues leads students to focus on these particular problems, but in fact, habitat loss and degradation have the largest impact on biodiversity. Further, many of the other major threats to biodiversity (e.g., climate change, pollution, etc.) can be directly or indirectly linked to habitat loss.

It is easy to connect complete habitat loss to loss of biodiversity – if a forest is cleared of trees, the diversity and abundance of associated flora and fauna will likely be reduced. But what about fragmented habitat? How does the size and shape of patches of forest or grassland influence remnant communities and ecosystems? The theory of island biogeography gives us hypotheses of how fragment size and isolation might influence populations and diversity. However, habitat fragments are embedded in an anthropogenically-influenced landscape and just how much that landscape influences the structure and function of the remaining habitat is an important question for conservation.

Nick Haddad and colleagues recently reported on the state of the world’s fragmented habitats; including a meta-analysis of long-term experiments specifically designed to test how area, isolation, and edge (distance to perimeter) of fragments effect the remaining communities and ecosystems. High-resolution satellite data revealed that 20% of the world’s forests were within 100 meters of a forest edge and 70% were within 1 kilometer, meaning most forests today are in close proximity of human activity.

A series of long-term (20+ years) habitat fragmentation experiments (see below), spanning multiple continents and biomes, have provided a data set of 76 studies testing how this proximity to human activity influences ecosystems. Specifically, this synthesis enabled Haddad et al. to test the effects of reduced habitat area, increased isolation, and increased habitat edge on a variety of community and ecosystem variables. Not surprisingly, all three treatment variables had negative effects on processes such as organismal abundance, species richness, pollination, nutrient retention, etc. and reduced habitat area and increased isolation appear to have the strongest effects.

Most striking however, was the accumulated long-term consequences of habitat fragmentation. By comparing changes in species richness, immigration, and ecosystem functions (e.g., biomass, total organic carbon, etc.) over time, a delayed effect of fragmentation appeared. That is, the proportional (negative) change in community structure and function increased over time. The negative effects of habitat fragmentation are not necessarily seen immediately after deforestation, and those effects may get worse over time – extinction and ecosystem function debts yet to be realized.

Large, expanses of forest still exist in South America, Africa, and boreal regions. Given that biodiversity loss itself can have strong detrimental effects on ecosystems, that climate change will likely exacerbate effects of fragmentation, and our economic incentives for protecting habitat, the analysis by Haddad et al. present a strong argument for maintaining these large stretches of uninterrupted forest.

 

Long-term experiments included the meta-analysis:

Biological Dynamics of Forest Fragments (Brazil, in Portuguese)

Kansas Fragmentation Experiment (USA)

Wog Wog Fragmentation Experiment (Australia)

SRS Corridor Experiment (USA)

Moss Fragmentation (UK, Canada)

 

Newly established experiments:

Metatron (France)

S.A.F.E. Project (Borneo)

April 1, 2015

Why Conservation? Communicating Applied Biodiversity Science

ABS_2color_web

Applied Biodiversity Science Program – Texas A&M University

You might have a favorite science writer. Mine are David Quammen, Bill Bryson, Carl Sagan, and Tim Flannery. Others may be more inclined to read Pulitzer Prize-winning and nominated authors like Jonathan Weiner, Siddhartha Mukherjee, or James Gleick, MacArthur-fellow Atul Gawande, or consummate greats like E. O. Wilson, Richard Dawkins, Stephen J. Gould, and Oliver Sacks. Or perhaps books aren’t all you’re interested in. In that case you may be a fan of Carl Zimmer’s blogging or the stories and editorials from journalists/authors Malcolm Gladwell or Stephen J. Dubner.

It’s likely you’ve read at least one of these authors. Like most readers you were probably impressed by how well they articulated the complexities and subtleties of their topic: everything from astrophysics to evolution, cancer, neurology, chaos theory, economics, and psychology. If you find an author who draws you into a topic that wouldn’t otherwise gain your attention, particularly an unfamiliar scientific discipline, take notice. Take stock of what they have accomplished by gaining your interest and curiosity. As George Gopen and Judith Swan stated in their 1990 for American Scientific, “the fundamental purpose of scientific discourse is not the mere presentation of information and thought, but rather its actual communication.” Good communication requires gaining the reader’s attention. Attention requires garnering interest and curiosity.

In our ever-connected world with vast communication and social networking ability, we have the ability to do just that. We possess the tools to communicate science to a diversity of people in a diversity of ways.

As a member of the Applied Biodiversity Science Program (ABS) at Texas A&M University I find myself in a position where communicating science is an imperative for success. The ABS program is graduate program originally funded by the National Science Foundation as part of their Integrative Graduate Education and Research Traineeship (IGERT) program. The principle mission of ABS at Texas A&M is to achieve integration between biodiversity research in the social and natural sciences with on-the-ground conservation practices and stakeholders.

To that end, a foundational component of ABS is to communicate across scientific disciplines with various institutional actors to facilitate broader impacts across the realm of conservation. In essence, the ABS Program seeks to produce applied scientists who can communicate effectively across disciplines. A natural corollary of this goal is the ability to communicate science outside the realm of science. In this respect, our ABS Perspectives Series is intended to communicate more broadly and inclusively who applied biodiversity conservationists are, what we study, where we conduct research, how we conduct research, and why we are doing it. The current issue of the ABS Perspectives Series, features experiences from the Caribbean, the United States, Sénégal, Ecuador, Nicaragua, and Costa Rica. Contributions cover topics ranging from captive parrot re-wilding with pirates to blogging in the Nicaraguan forest with limited Internet access.

Perhaps more importantly, the ABS Perspective Series wants to reach out and share ABS student and faculty experiences with a diverse readership to raise awareness of biodiversity conservation issues. Outreach is an important axiom of actionable science, especially outreach that informs, improves and influences management and policy. I consider both the ABS Perspectives Series and BioDiverse Perspectives outreach initiatives to communicate the biodiversity conservation mission to the general public, communities where our research has been conducted, fellow academics and practitioners, and institutions that can provide logistics, infrastructure, and support. We must intend to make and practice making our research accessible and intriguing to everyone.

November 18, 2014

Deconstructing Defaunation

Many species globally are threatened by numerous biotic and abiotic stressors, resulting in declining population and shifts in ecosystem functioning.

Many species globally are threatened by numerous biotic and abiotic stressors, resulting in declining population and shifts in ecosystem functioning.

Science recently released a special issue on defaunation, which spanned seven articles detailing the recent decline in animal species diversity and abundance.  Among others, the issue included two peer-reviewed articles, an opinion piece, and an analysis of national policies tied to global and local conservation strategies.  The statistics associated with defaunation are sobering, but the issue presents a few solutions to help us curb this global environmental crisis.

First, a damage assessment.  According to Defaunation in the Anthropocene, between 11,000 and 58,000 species go extinct each year.  At least 16% of all vertebrate species are endangered or threatened, and there’s been a 28% decline in their abundances since the 1970s.  Approximately 40% of invertebrate species are considered threatened, though less than 1% of described invertebrates have been assessed.  There is data to suggest that invertebrate species’ abundances are also decreasing, but it’s difficult to put an exact number on that decline since they are not as well monitored as vertebrates.  On a global scale, these statistics may be underestimated because our monitoring practices bias our data toward specific taxa.  Groups of large and charismatic organisms, like mammals and birds, get most of the attention because they are easier to monitor and more sympathetic than invertebrates, amphibians, and reptiles.  In some systems this is beneficial, where large mammals and birds are the most threatened and contribute significantly greater function to an ecosystem than smaller organisms.  However the opposite can be true in other instances, so it is critical that we prioritize greater sampling of underrepresented groups.

Additionally, there is concern that such measures of declines in species and abundance may not reflect the true extent of our ecological troubles.  Shifts in ecosystem compositions may not be reflected in a given measurement of biodiversity, yet are nonetheless indicative of environmental change.  The primary goal behind many conservation strategies has been to restore a species or population to a certain number.  While population viability is critical for any species, the authors argue that ecosystem functionality is a useful yet underutilized goal for conservationists.  With this goal, the composition of an ecosystem (i.e. the identity and abundance of resident species) can be more flexible, as long as the ecosystem functions in a similar way.  The issue with this then becomes how to measure ecosystem function, or rather, against what do we compare it?  Do we set an arbitrary time in history that we would like to restore it to, or do we attempt to maintain its function while integrated with a unique environment managed by humans?  Some proponents of the latter strategy see historical comparisons as unrealistic and uninformative, especially given our changing climate.  Regardless, restoring the functionality of ecosystems is a key predictor of the future success of not only animal and plant populations, but the human population as well.

One of the strongest arguments this issue makes derives from its use of specific economic values of animals and ecosystems.  According to the article Wildlife decline and social conflict, the harvest of land and sea animals accounts for $400 billion annually around the world.  Defaunation in the Anthropocene claims that pest control by native U.S. predators is worth approximately $4.5 billion annually, and that the decline in North American bat populations (a specific type of pest controller) has cost the agriculture industry $22 billion in lost productivity.  Insect pollinators are required for about 75% of the world’s food crops, and are therefore responsible for approximately 10% of the economic value of the entire world’s food supply.  According to the World Bank, food and agriculture represents about 10% of global GDP, which in 2012 was estimated at $72 trillion.  If we take total food supply to be approximately $7.2 trillion (again, estimating), then insect pollinators are worth around $72 billion dollars.  These estimates apply tangible figures to a broad and occasionally overwhelming issue, and may be good starting points to unite many different stakeholders under a common currency.

The article Reversing defaunation: Restoring species in a changing world details the different strategies conservationists use to preserve species abundances and their associated ecosystem functions.  These strategies can broadly be grouped into two categories, translocations and introductions.  Translocations involve moving individuals within their indigenous range to either reinforce a local population or to reintroduce them following a local extinction.  Introductions, on the other hand, move species outside of their indigenous range to prevent a global extinction of a species or to replace a lost ecosystem function.  Though planning a conservation strategy in terms of these labels can be useful for setting long-term goals, they are not mutually exclusive.  Certain strategies can incorporate aspects of both translocation and introduction, or can introduce a species both to preserve its numbers and to restore ecosystem functionality.  Therefore, it’s best to use these terms as guidelines for how to measure the success of any plan rather than as constraining requirements.

These losses in biodiversity, and their associated shifts in ecosystem functioning, are primarily driven by a combination of over-hunting, habitat destruction, impacts of invasive species, climate change, and disease.  The Defaunation articles make a point of addressing national policies aimed at preventing species extinctions, namely those regarding over-hunting and poaching.  Many of these policies simply impose penalties for illegal hunting rather than address the underlying causes of the issue, poverty and starvation.  While it’s unrealistic to expect a conservation plan to alleviate world hunger and income inequality, it may be useful to consider animal overexploitation as an unintended side-effect of the economic cycle caused by scarcity.  Supply and demand states that as a species becomes less common, its value on the market rises.  However, this scarcity also leads to a reduction in the amount caught per unit effort.  The rise in price drives a greater hunting effort by the sellers, further decreasing the population, and the cycle begins again.  Since many of these hunters are using their profits to feed themselves or their families, simply enacting penalties for poaching may not have the intended effect.  Overhunting is not a simple problem, and most likely will not have a simple solution.  However, the only way we can begin to address it is by determining its causes.

September 30, 2014

FLUMP – Sargasso Sea biodiversity, penguin citizen science, criticism and more!

This place isn't doing so well

It’s Friday and that means that it’s time for our Friday link dump, where we highlight some recent papers (and other stuff) that we found interesting but didn’t have the time to write an entire post about. If you think there’s something we missed, or have something to say, please share in the comments section!

A study by Huffard et al. published this month in Marine Biology gives evidence for declining biodiversity within the Sargasso Sea.  The authors compared samples from 2011 and 2012 with those taken back in the 1970s, and found declines in species richness, diversity, and evenness.  It is unclear whether these community shifts are inherent to the Sargasso Sea’s ecosystem or if they are driven by changes in sea surface temperature and pH.

A new citizen science project called Penguin Watch lets you look at images taken by researchers in the Antarctic and count how many adult penguins, chicks, and eggs are in each photo.  This data will be used to better monitor and protect penguin populations against anthropogenic threats such as climate change and human stressors.  I’d like to think Bruce Wayne has a Penguin Watch as well, making all who contribute to this research a little more like Batman.

An interesting article on Science Careers details the uphill climb a lot of doctoral graduates face when seeking employment outside of academia, and the drawbacks of taking a job you are overqualified for.  – Nate Johnson

For those of you who enjoy watching the IDH tennis match, Michael Huston offered a critique of some recent critiques (how meta) of the IDH, and its cousin the intermediate productivity hypothesis, in the context of ecological logic vs. ecological theory. It’s here in this week’s Ecology.

How much evidence is there really that co-evolution promotes diversification? Hembry et al. in last week’s AmNat.

And because I’m on a roll (in a rut?) of reading papers that offer primarily criticism: “A critique of the ‘novel ecosystem’ concept” by Murcia et al. in the most recent TrEE. -Emily Grason

Here is a couple of interesting special issues that came out recently; the first is a special issue dedicated to Functional Biogeography, published in PNAS and the second one is an Oikos’ edition dedicated to soil food webs– Vinicius Bastazini. 

What are the 71 important questions for the conservation of marine biodiversity? You can read it here in the latest issue of Conservation Biology. – Kylla Benes

 

September 26, 2014