Envío Digital
Central American University - UCA  
  Number 311 | Junio 2007



We Barely Know the Wealth of Biodiversity Surrounding Us

A research biologist shares information and experiences regarding Nicaragua’s biodiversity, our limited knowledge of it, the threats it faces, and the chances we still have to understand, defend and rescue it.

Antonio Mijail Pérez

Do we Nicaraguans know what animals co-inhabit our our country with us? Not really. The first thing we need to understand is that invertebrates, which range from primitive protozoa to advanced insects and crustaceans, provide our planet’s greatest diversity. These animals are also the majority in Nicaragua.

Limited and uneven research

One of Nicaragua’s greatest problems in getting to know its biodiversity is the disparity of our knowledge. We have very advanced knowledge about certain species and groups, yet know virtually nothing about others. There is no Academy of Sciences or Biodiversity Institute in Nicaragua. Some research centers, NGOs and dispersed researchers are studying biodiversity, but so few that only three groups are studying the entire world of invertebrates, with its hundreds of thousands of species—our Gaia Association; the Central American University’s Malacology and Animal Diversity Center, which is working with mollusks and other non-insect invertebrates; and León’s Entomological Museum, where they work with insects. Other people are concentrating on applied topics, such as the UCA’s CIDEA or UNAN Managua’s CIRA, but only the three above-mentioned organizations are systematically researching these groups of fauna. The two herbariums—in the UCA and the UNAN León—work with collections, but none of the groups doing any sort of work with vertebrates have collections; in other words, they don’t collect, have back-up material or collections or any kind of museum.

There are no invertebrate collections in Nicaragua. There was a project some time ago in the Ministry of Natural Resources and the Environment (MARENA), and there’s a small museum in the UCA with some specimens. The most relevant collection consists of the birds and reptiles Father Astorqui gatheredin his time. It’s in a small museum and couldn’t grow much more given the UCA’s budgetary limitations. I understand it has the value of being Nicaragua’s only museum of our own vertebrates. There are also some collections of reptiles and amphibians preserved in alcohol by Jaime Villa, a prestigious Nicaraguan biologist currently working in a US university. There also small collections of animals from our country in European and US museums.

It’s hard to calculate the extent of our biodiversity. We have a pretty complete list of birds, containing some 650 species, although some are almost certainly still missing, as new ones are continuously being added. But a list isn’t good enough, because we don’t have morphological characterizations, distribution maps or ethology data for these birds. In the area of amphibians and reptiles we’ve now moved beyond the limitation of a simple list and are beginning to produce keys for identifying them.

As far as invertebrates are concerned, we only have information on mollusks, insects and some precise data on crustaceans. We have pretty complete data on mollusks from the Pacific region, but only lists of insects that date back to 1999. It was a tremendous undertaking, but we still only know the name of each insect and two or three locations where they were collected. We don’t even know how widespread or abundant each species is in Nicaragua and often don’t know what they can be used for. We can’t make forecasts without good maps of a species’ distribution and abundance. We can’t say, “Yes, this species could be used because it’s very abundant.” If a species is very abundant, we can make some use of it, but if it’s rare, we have to protect it.

In mammals, we also have a list of “charismatic” animals—the large ones, the ones you can see. But once again we haven’t gotten beyond a simple list, although I understand that a more in-depth work on bats is going to be published soon.

In search of the new discovery

Nowadays, when ecological tourism is such a hot topic, the more detailed studies could be very useful for us. For example, bird-watching tourism is very much in vogue in countries of the North and people are prepared to travel far and wide just to see some species they’ve never seen before. They are image collectors. They want to see a quetzal, so they check out where it is and then travel there to see it. They look for some mountain lodge and come only to see that species. The charismatic species currently have that added value: the power of the visual image, the hope of photographing the animal, of seeing it up close.
As biologists, our interests and tastes don’t run along those lines. Sometimes our greatest joy is to find an endemic—a species that can only be found in a specific locality. How does one know it’s endemic? In principle because it’s cited in the bibliography, because it was discovered in a certain place and has only been reported sighted there. Until somebody finds one elsewhere, that species is endemic. When someone starts working in a locality and finds a species that seems to be new to science, in principle we must consider it endemic.

In the group we’ve done most work on in Nicaragua, the mollusks, we’ve found some species that might be endemic because they haven’t been described by science and have been found in very concrete localities—such as Pacific areas of primary forest that have remained intact since pre-Colombian times. Although they’ve been modified a bit, these forests have the characteristics of the original, pristine forest in that area.

Such forests are only conserved in a very few points of the Pacific. There are a few tiny patches in Laguna de Apoyo, and some in El Chocoyero, in Masaya. We also found some patches of original forest around the Casita Volcano before the mudslide. There’s another little patch further north, in the Somotillo area, and a few more around the Mombacho Volcano, near Nandaime and in the Chacocente area.

There aren’t as many as we would have hoped in the Caribbean, because the agricultural frontier has encroached too far. There are zones out around Nueva Guinea, for example, where the agricultural frontier has almost reached the Caribbean Sea, partly thanks to Hurricane Joan in 1998, which flattened most of what was left of that forest. But there are areas in the Caribbean where little if any research has been done. We’re now looking to collaborate with some colleagues from a US NGO called The Nature Conservancy. They’re interested in investigating northeast Nicaragua, from the Bosawás reserve eastward, a nearly untouched zone. In Bosawás itself there have already been some research efforts, given that it’s a bi-national protected area as Bosawás borders the Honduran Río Plátano reserve. But animals don’t understand either policies or borders. They move and spread out wherever they find favorable ecological conditions. I think some very interesting things are going to show up in that virtually unstudied zone.

It’s unlikely we’ll find any large animals that aren’t yet known. But bats are small mammals and there could be some new species or subspecies or varieties with some interesting modification. The rodent world could also provide some surprises. We could also find unknown birds in that unexplored area, because there are birds associated with primary forests that live very high up, at certain canopy heights where they can’t be seen.

And insects? They’re going to be offering us surprises for a long time to come, because insects are a “mega-diverse” group everywhere in the world; their species aren’t counted in the hundreds, like mollusks, but in the thousands. A million insect species have been counted on the planet, in contrast to some hundred thousand mollusk species.

A valuable discovery in
applied farm research projects

Without losing our interest in biodiversity, we’ve been moving from natural settings and the descriptive field into agricultural bio-indication. We’re promoting applied research projects on farms. When I was mappings the Pacific for my doctoral dissertation, I realized that Nicaragua is one huge farm and that the dream we biologists have of organizing protected areas where everything is in perfect order is a utopia in countries like our own. We have to seek models that allow us to conserve the biodiversity in productive settings.

You don’t get very far with conservationist ideas in a country with so many problems, so much poverty. Pure conservationism rings like strange and exotic music in Nicaragua. To be responsible, we have to compromise to both conserve the biodiversity and keep the productive processes moving along. Many people now think and speak the same way, having reached this conclusion down different paths.

Other Latin American countries have also come to similar conclusions. We’ve been battling with statistics and math for years in search of an alternative model or models to reconcile biodiversity conservation and production and that can work both in Nicaragua and in Bolivia. With funds from a Guatemalan NGO called ASIES, we did a small project in 2002 with the idea of finding correlations and came up with a first-level guideline. Although the sample was too small to provide categorical conclusions, we did notice a relationship between cattle ranches with high forest vegetation and the tendency to be self-sustaining. We saw that the more trees there were, the greater the production yield, because the trees shade the cattle, so they lose less energy than when they graze under full sun. And because the forest cover keeps the soil from drying out so much, the cattle have more grasses. In addition, the species cultivated on those ranches provide cattle feed in the form of pods and shoots, providing the cattle more to eat than just pasture grass. On the farms we studied, the farmers don’t have to give their cattle food supplements. The farm thus becomes an autonomous ecosystem that doesn’t depend on outside inputs. And if there’s a moderately good rainy season that leaves the soil saturated, almost the only the thing the cattle need is water. The pasture grass will last through the dry season because there’s enough forest to conserve it or it can be used alongside forage from the ranch’s own forage banks.

The cows move contentedly among the trees. The traditional image of cows grazing on immense grasslands is losing sway. It was an extensive production model that doesn’t work. We’re now focusing on more intensive production: improved pastures dotted with trees providing less deforestation and a more productive herd. Science is testing out different models. We always work with the trial and error method and as we’ve now realized that extensive cattle ranching is going to wipe out the entire planet’s forests, the world trend is to change the cattle-raising model. Costa Rica and Colombia are already moving in that direction: more trees on the cattle ranches to improve the quality of both the pasture and the cattle and to conserve the woodlands. In principle, I think this model is exportable. When I told some US citizens living in Bolivia about our project’s findings, they said they’d observed the same thing in Bolivia: ranches with significant tree coverage are more sustainable and their cattle develop better. This discovery leads to the following questions: what is the most appropriate coverage for each ranch and each cattle herd? And what are the variables of climate, farm altitude, nearness to a water source?

People from the World Bank we’ve spoken to about this commented that we should do a study with satellite images if forest coverage is so important. We said that would be fine as a first approximation, but that a satellite can’t detect whether a green patch has one or a variety of vegetative species. And that’s very important, because that forest is in danger of disappearing if it’s a single species, but not if there are various species. We also need to know if they are species that can complement the cattle’s food intake. Moreover, is the forest diversity associated with various flora and fauna that could be of interest to a rancher? He could be interested in keeping bees for honey, for example, and not just any old plant will guarantee him bees. Or he could be thinking about ecotourism, making a conservation perspective important. Many areas of Nicaragua mark the limit of the southern distribution of some valuable North American species and a rancher might take an interest in having some of those species on his ranch to attract tourists. He might want trees that guarantee monkey settlements on his ranch… I think I managed to convince my colleagues by explaining all of these possibilities.

We’re transmitting knowledge, a methodology to the producers, and they’re transmitting very important things back to us. One of the things we want to achieve with our work is to homogenize the knowledge of people in a particular area. For example, some farmers we work with know a great deal about ethno-botany, about botany related to curing illnesses. But they don’t have that knowledge the slightest bit systematized, so it will all be lost when those men and women leave or die. We’ve interviewed them and discovered that they all have a piece of the knowledge, but none of them has the whole package. We had a project—although it never materialized because we couldn’t find financial backing—to put together a book with full-color images of the plants where we’re working and a description of their uses: medicinal plants for people and for cattle, abortive plants, hallucinogens…

All ecological disasters
start with deforestation…

Biodiversity is under threat throughout the Meso-American region, which scientists now view as a “hot zone.” In the global-level mappings, “hot zones” refer to the planet’s endangered areas with the highest biodiversity. Central America is a socially and financially impoverished region, but it’s very rich in biodiversity. And that biodiversity is being affected by devastating deforestation. One way or another, all the disaster and destruction starts with deforestation.

Central America has a great level of biodiversity subjected to a great level of threat, and Nicaragua is possibly the most threatened country. Although El Salvador’s case is very serious, the degree of disaster in that small country with such a huge population density means that it has already touched bottom and they are beginning to invest in recovering ecosystems. The big problem in Nicaragua is that, despite how much we’re destroying, we have so many natural resources and our territory so large that we still aren’t aware of our responsibility, or the consequences of our irresponsibility.

…and turn into a water crisis

The problem I’ve noticed here among people of my generation is that they were born in a country that was very wealthy, unlike other Central American or Caribbean countries like Haiti or Cuba, where the water shortage is age-old. If they had been born in one of those countries, they would take the water issue very seriously. I’ve never seen anybody in Cuba doing what so many people in Nicaragua do: wash down the sidewalks and asphalt streets with a hose, wasting water. One of the reasons I fell in love with my wife, who’s Nicaraguan, was that almost the first thing she said to me when we met was “I’m very worried about the water.” That really knocked me out, and I thought: This woman is something else.

One particular experience with water has marked my life. When I was 16, I made my first important field trip in the Viñales valley, in western Cuba, with a number of friends. We got lost in one of those intra-mountain sub-valleys for nearly three days. We were packing cameras and had collected a lot of rocks and plants. We had everything—except water and food, and of course we didn’t want to throw away our collection. We slept under clumps of trees, suffering from horrible thirst for three days. We nearly died. That awakened my concern for water even more.

As Nicaragua is the largest and least populated country in Central America and has the most resources, people don’t get concerned; they aren’t getting alarmed. But the water in Lake Managua is already undrinkable and Lake Cocibolca is heading in the same direction, despite being an enormous reservoir of water that should be treated with great care. Nicaragua’s crater lakes, those incredibly interesting closed bodies of water, should be especially cared for.

Whole worlds in a drop of water

There’s a famous entomologist who has focused on calculating the immense diversity of insects on our planet, and he’s published some very interesting examples. For example, in a forest in Panama similar to Nicaraguan forests he studied all the insect species living in a single tree—from those who live in the soil among the tree’s roots to those in the highest part of its canopy, and including all those living in its trunk. He found a huge number of species. Then he compared the diversity of species of the first tree with that of the tree alongside it, and saw that they only shared about half the species. This suggests that there are spectacular numbers of insects in an entire forest. We’re talking about veritable “tree islands” with a multitude of inspect species living only in that one tree.

The tropical climate contributes greatly to these leaps of biodiversity. The closer the latitudes to the tropics, the more diversity increases and life multiplies. This doesn’t happen in cold climates. I’ve seen the same phenomenon in the Viñales area of Cuba, which is one of the island’s most emblematic zones for the plethora of its biodiversity, being particularly rich in malacological diversity. I’ve seen a species of mollusk there that’s associated with one specific rock, and isn’t found on the rock three meters away, where a different species of mollusk lives. The vital dominion of each of these species is very limited. They’re species that only move a few centimeters in their entire life, never making it from their rock to the one alongside. In such cases, we’ll lose the species if we lose the rock. There’s one concrete mollusk family that has some 600 different species in Cuba, all of them with the same kind of tiny, precarious habitats. And that same thing that happens in rocks also happens in trees or in some closed bodies of water such as Nicaragua’s volcanic crater lakes, which are the home to unique fish species.

Speaking of mollusks…

Mollusks are one of the most biodiverse groups of animals on the planet—the second most biodiverse invertebrates after the anthropoids. They’re found in the ocean, in fresh water and on land. Over a hundred thousand living species and some 35,000 fossil species have been described, since they have a geological history that dates back to the Cambric era. Cuban peasants know mollusks because the ones in the Caribbean are large; they’re part of the landscape. That doesn’t happen here in Nicaragua. Mollusks are very small throughout Meso-America because its volcanic soil doesn’t let them grow very large. The malacofauna of the tropical region start being charismatic up toward the Yucatán and the Caribbean and down toward South America.

But while Meso-America’s mollusks are very small, there’s an enormous diversity. When I came to work in Nicaragua and started collecting mollusks, I was very disappointed, coming from Cuba, where they’re big and visible. But then I decided to read Alan Solem, one of the the 20th century’s most important mollusk researchers. In the introduction to one of his books he tells of one of his first work experiences in the Pacific Islands. He explains that he began to collect and found very little diversity. Reading it I realized that if that happened on those volcanic islands, the same thing was probably true in Nicaragua: mollusks here ought to have other characteristics. The size of a mollusk depends on the calcium carbonate they find in the soil to make their shells and there’s a smaller concentration of calcium carbonate in the Meso-American soils than in other tropical soils.

Why care about the little guys

When we see the number of mollusks living in the soil and of insects living in a tree, we tend to think they’re a bunch of tiny critters of absolutely no importance. But do we know how these little guys are related to the food chain of other more emblematic animals? Or do we know whether this tiny insect is the pollinator of a species that does interest us? Everything in nature is related.

Some biologists call anything that’s big, eye-catching, perceptible “charismatic biodiversity”—I’ve even started using the term myself. They are the big mammals, big birds, big reptiles, marine turtles, royal eagles… That’s the biodiversity that gets funded, but there are very few species in that range; only a few hundred. The non-charismatic biodiversity isn’t generating awareness yet.

The most important biodiversity on our planet, however, is the non–charismatic kind, which includes hundreds of thousands of species, some of which might provide a cure for cancer or other diseases. There are species of small marine mollusks from which is extracted venom more powerful than that of poisonous snakes. There are anemones—a “sessile” marine invertebrate, which means an unmoving one that’s stuck to the bottom—from which some prostaglandins used to treat cardiac problems are extracted. We still don’t even know the variety of resources available from non-charismatic biodiversity.

Without the little guys
the soil would be sterile

One problem of the current socioeconomic model is that it posits success only for city people. A whole different strategy has to be designed. Rural people’s living standards need to be improved. We’ve observed that our peasant farmers don’t have any ecological awareness; at least, not enough. They aren’t aware of the need to care for the non-charismatic biodiversity because they can’t see it. Some farmers relate more to birds and know a little more about them. And some relate to trees and know something about them, including their names. Some can also name the non-vascular plants. But the fauna groups they can’t see, above all the fauna in the soil, is like a big black box still to be opened.

We did an experiment with farmers in the Patastule area of Matiguás. They started by taking soil samples with us explaining how to do it. Afterwards, they were shocked when we showed them the number of animals in the soil they had collected. They had never imagined there was so much life in the soil where they lived. We found 14 mollusk species in one of their farms. They weren’t microscopic, but there were very tiny, all associated with the topsoil.

Human beings typically look straight ahead or upward, and farmers are no exception. They worry about their cows and the pasture for them, but not the other components in the soil even though they have such an important role in the productive ecosystem. If it weren’t for the mollusks, for example, the millipedes or the earthworms, their soil would be sterile. Earthworms are prodigious. They feed from the soil, but they eat mineral elements from that soil that they later incorporate back in through their excretion. They fertilize the soil with that waste, which is called “casting.” We still don’t have a base study of Nicaragua’s worms. It’s a group I want to work on, but I haven’t even had time to start collecting them, because earthworms are in a lower stratum, deeper in the soil than those mollusks we found or other groups we’re beginning to work on.

We’re starting to work with centipedes, millipedes and another series of very important arthropods that aren’t given much attention because they aren’t very diverse—they only have perhaps 30, 40, 50 species. They’re all associated with the soil and are strategic. For example, diplopods—arthropods commonly known as millipedes—don’t help make soil, but they do aerate it. They make tunnels that oxygenate the soil. The soil is a living thing and if it doesn’t get oxygen it begins to lose its productive quality. If we don’t conserve these animals, the soil will lose quality. We’re trying to transfer all of this knowledge to the farmers.

What are the characteristics
of Meso-America’s biodiversity?

The big mammals that used to live in Meso-America are already extinct. The biggest ones we have today are jaguars and tapirs. We still have really spectacular birds: the quetzal, the bell bird, the toucan, the whole macaw family… beautiful birds. There’s also an extraordinary diversity of insects, which are very pretty too. The most emblematic insect orders are the Lepidoptera—butterflies—and the Coleopterans—beetles. There’s an enormous, really fascinating variety. On one trip we collected beetles from the Dynastidae family, so named because of a big horn that gives them a kingly element. Absolutely beautiful. In Nicaragua we have the Morpho butterfly, of an extraordinary metallic blue color. There are four or five genres of beautiful Lepidoptera. In reptiles we have the marine turtles that come to special areas in Meso-America to lay their eggs, of which Nicaragua boasts two: La Flor and Chacocente. Our mollusks are small and not very colorful. They’re not colored like our birds or the mollusks of the Antilles.

The characteristic aspect of the biodiversity of Meso-America as a whole is that it belongs to a zone connecting the two great continental masses of North and South America. Human, flora and fauna groups have all passed through Meso-America on their way North and South and continue doing so. They particularly pass through Nicaragua because we’re in the very middle of Central America, the center of the continent.

Many animal and vegetable species converge in Nicaragua, which is the southern distribution limit of many species. And some species that come to Nicaragua have their northern limit here. The most emblematic cases in the plant world are the Ocote Pine and the Liquidamber. Both grow in North America and reach no farther south than Nicaragua. There are also butterflies, mollusks and reptiles that have their limit here. We’re living on a biodiversity frontier in Nicaragua.

Our endangered species

Various species of our flora and fauna are seriously threatened, some of them charismatic and some of them not. The harpy eagle, which is seldom seen, and the quetzal, which is not especially abundant, are among them. Also threatened is the bell bird, which is heard but hardly ever seen because it lives in high mountain forests and isn’t abundant. Some species are the object of abuse, such as the toucans. Macaws are also being abused, making their situation dangerous even though they have a healthier population. They’re under less threat from being sold at traffic lights—which is serious enough—than from the destruction of the forest they live in.

We are the object of illegal trade in fauna and a while ago it was discovered that people at all levels were involved in the trafficking of birds. There’s a lot of money to be made in this business. It has now become fashionable to trade in epiphytes, plants that live off of other plants. Some very pretty ones, such as orchids or bromeliads, are sold at the stop lights. Sometimes I feel powerless. We have some laws, some mechanisms, but they only partly function. And in this terrain, as in others, repression doesn’t work either.

It’s positive that Nicaragua has signed nearly all the regional and global environmental agreements, which helps put pressure on the governments. And even if they’re only paper, these agreements help in the task of organizing the defense of natural resources. I think the current setting is a good bit more favorable than the one I found when I began living in Nicaragua in 1991, when I was 28. Only a few of us were working on this at that time. There’s a new generation of young people, many of them educated in the UCA’s Ecology and Natural Resources major, who are now working in other universities or NGOs; some even have executive posts in the government. They’re giving this effort a new dynamic and a new sensitivity. We now have more informed and experienced people who are on the move, go to international congresses and have a serious opinion.

Do we still have the time and resilience?

Will there be time to reverse the ecological disaster? To respond adequately, we need to consider the concept of resilience, which means to resist, the capacity to recover. I’ve seen forests in the tropics that recover extraordinarily quickly. If you leave a highway unattended, you’ll find it destroyed within five years no matter how good it is, because if a bank of seeds got left in some small little crack it will have covered in the highway in vegetation in five years time. The natural systems have an incredible capacity to recover. And they’re even more resistant in the tropics.

I believe there must have been proto-civilizations on our planet that we don’t know about, with constructions that have totally disappeared, erased by biological, physical and chemical processes, by climatic changes. Life recuperates spectacularly quickly in our lands, but not always, and only within certain limits. If we clear-cut a forest and use that soil for pasture for a long time, no seed bank will remain. So where will the forest get the seeds to grow back? If the forest had a nearby water source, birds, the wind and other forces could bring seeds that would begin to colonize the soil. And if there’s a forest nearby, it will have more probability of recovering than if the next forest is far away, or there isn’t one at all. Resilience is the forest’s capacity to regenerate itself. But there’s very little if any resilience in a clear-cut forest that has to begin its recovery process from nothing.

The catastrophe isn’t for
future generations; it’s already here

Four or five months ago I gave a bio-geography course in a doctoral environmental sciences course at the Engineering University. Half the students were architects. I told them that architects have to change their mentality; that we have to encourage a generation of architects that propose and push for models of cities with less asphalt. Managua is an extremely green city, although not because of any such thinking. From above, it’s almost impossible to see the houses for all the trees. But that’s unintentional; it’s pure accident. And that very unintentionality is in danger. They’ve cut down all the trees that used to be in front of the new malls and planted strawberry trees, which is the national tree and is very beautiful, but it’s extremely slow-growing. Along the Northern Highway there used to be cassia trees, with their spectacular yellow flowers, and oaks. But they’ve all disappeared as well.

I also posed this question to the future architects: how is it possible that in a city with so much wind and sun we build closed places to live and work that require air conditioning? The architects became more sensitive, but when I warned them of the seriousness of the current situation, the lack of awareness, they asked if it was really necessary to be so alarmist. I reminded them that climate change is already with us.

A few years ago I saw a movie in which London was constantly flooded and invaded by a plague of rats. That’s not fiction; it really could happen. Many of the drainage problems we already have in Managua are a consequence of the kind of tree species we’ve cut down or the inappropriateness of those that remain. Managua can yet be saved, because it still has many green spaces—perhaps because there’s not enough money to urbanize everything. If there were, wouldn’t those green spaces soon be replaced by cement ones?

The approaching catastrophe won’t be bequeathed to future generations. It’s already here. The number of hurricanes in recent years, the temperature changes—everything we’re seeing and feeling—are clear and palpable signs of global climatic change. It’s not a question of leaving the pending catastrophe for others to witness: we’re already seeing it with our own eyes.

Antonio Mijail Pérez is a consultant with the Gaia Association and former director of the UCA’s Center of Malacology and Animal Diversity.

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