Van Vliet's Frog

Van Vliet's Frog is one of several names of this species (Smilisca baudinii) common to areas with permanent water in Laguna de Apoyo Nature Reserve, Nicaragua. Also called the Mexican Tree Frog, it is truly arboreal, and uses "sticky" flat foot pads for adhesion rather than claws, which also make smooth house walls ideal microhabitat for this animal. Rain keeps things wet throughout the area six or seven months a year, but there are five months without surface water in many places in the reserve. Standing water is common, however, around houses and other structures, the lake itself, and a handful of creeks which flow into the lake. This species commonly enters Estacion Biologica, as did the one pictured below.

Van Vliet's Frog (Smilisca baudinii) on a wall at Estacion Biologica, Laguna de Apoyo Nature Reserve, Nicaragua. Photo by Jeffrey McCrary.

This individual shows two ticks in the above photo, on the left side of the abdomen. Almost all frogs of this species have this coloration in Laguna de Apoyo Nature Reserve, with a camouflage-like pattern on the back, and leopard stripes on the legs. 

Smilisca baudinii in Estacion Biologica, Laguna de Apoyo Nature Reserve, Nicaragua. Photo by Jeffrey McCrary.

Smilisca baudinii is found in several disjunct populations from southern Texas to Costa Rica, placing our population near the southern edge of the overall species range. The species is generally common where found, but great regional variation has been noted, in fact this variation has led to some populations being described erroneously as unique species. In our area, we recently documented an interesting color variation, a so-called "light phase" (see below).

Smilisca baudinii light (green) phase, Estacion Biologica, Laguna de Apoyo Nature Reserve, Nicaragua. 

 This individual was sighted on a wall in Estacion Biologica and no one could identify it at first sighting. Some colors, particularly the markings on the inferior side of the animal, were more accentuated, whereas the back was completely covered in a vibrant green. In some populations, the so-called "light" phase is actually lighter than the more common mottled patterned individual, but ours is actually considerably darker and brighter.

In the photo above, one can appreciate the camouflage pattern muted by the bright green coloration.

The Van Vliet's Frog is a good jumper, and can be seen easily at night during hard rains, jumping on the ground, although it prefers vertical surfaces when dry.

Van Vliet's Frog (Smilisca baudinii) in Estacion Biologica, Laguna de Apoyo Nature Reserve, Nicaragua. 

Smilisca baudinii escaping Jeffrey's grip.

Laguna de Apoyo Nature Reserve can be a great place to observe wildlife. Ecotour companies regularly make excursions in our area. If you are interested in making a nature tour in the area, you are welcome to contact us.

Click on the "escudo" to contact us.

Video: Endemic Fish Species in Laguna de Apoyo, Nicaragua, Threatened by Humans

The volcanic crater lakes of Nicaragua attract lots of tourists, both Nicaraguans and foreigners. The water-filled craters are all beautiful, each with its own special features. Eight of these lakes, however, have endemic fish species, daughter species of the ancestral form of the Midas cichlid (Amphilophus citrinellus), living in them. The water of most of these lakes is transparent, perfect for observing these fish while SCUBA diving.

During the nineteenth century, scientists and explorers admired the wide variations in color and shape among the Midas cichlid group, so much so that several species were described during the succeeding fifty years. Most of those species are today lumped back into A. citrinellus, given that this is the first described of the group from Lake Nicaragua. Its sister group, A. labiatus, has similar features but is generally longer and sleeker bodied with prominent lips and frenum. This fish became incorporated into the aquarium hobby trade in a brightly colored form, and is still known as the red-devil cichlid. Only these two species "survived" the scientific scrutiny of the first three-quarters of the twentieth century.



Amphilophus labiatus showing its prominent lips in Laguna de Xiloa, Nicaragua. Photo by Ad Konings.

People knew these fish populated not only the Nicaraguan Great Lakes, but also the volcanic crater lakes along their western shores. The late, visionary scientist George Barlow applied for the first time, multivariate analysis to the morphological characters of fish populations in this group to demonstrate convincingly that A. labiatus and A. citrinellus were different species, and that in Lake Apoyo, a unique species exists as well, which he called the arrow cichlid (Amphilophus zaliosus). This species, more elongate than A. citrinellus and lacking the fat lips of A. labiatus, was found in Lake Apoyo. 

A pair of Amphilophus zaliosus on nest, in breeding coloration. Photo by Ad Konings.

The sacred trinity of A. citrinellus, A. labiatus, and A. zaliosus stood through the remainder of the twentieth century. During the current century, we incorporated the talents of Jay R. Stauffer, Jr. in the taxonomic descriptions of fishes in this group. To date, he has led the descriptions of eight additional species-three from Lake Xiloa, and five from Lake Apoyo, Nicaragua. They will be discussed in a coming blog entry. Most of the species from Lake Apoyo can be appreciated in the video below.

Video by Balasz Lerner.

This second video, produced by Fabio Buitrago, shows underwater footage of endemic fish species in Lake Apoyo, facing a crisis of man-made dimensions-garbage. Everywhere. Why must we pollute their home? These fish-six species known and others not yet discovered-only live here in this lake.

The most common of the fish in this video, and in just about any part of the lake where we have looked, is the little Apoyo cichlid, A. astorquii. It was named in honor of Father Ignacio Astorqui, a Jesuit priest from Spain who devoted much of his life to the study of freshwater fishes of Nicaragua, and wrote the first comprehensive guide to them. A breeding pair with their fry are shown below:



Amphilophus astorquii pair caring for fry, Laguna de Apoyo, Nicaragua. Photos taken during scuba diving by Adrianus Konings.

Would you like to help us protect and study the endemic cichlid species of Laguna de Apoyo? One of these species is already on the endangered list (Arrow cichlid, Amphilophus zaliosus, Critically Endangered-IUCN). Nicaragua needs your help, because the threats are many, and resources are few. We are seeking divers, biologists, people with experience in excel, and volunteers without any specialized skills to help us in this project. Please contact us if you would like to participate. The Laguna de Apoyo Spanish School also supports this project by providing a portion of its proceeds to fund our studies and conservation efforts. Would you like to learn Spanish? Think about attending our program, and go diving with us, too!

Animal Rescue V:White-throated Magpie-Jay

We have had a small success at Estacion Biologica FUNDECI/GAIA. Our care of a sick, nearly dead White-throated Magpie-Jay (Calocitta formosa), has resulted in a healthy, juvenile feeding on his own, and living as an active part of the forest in Laguna de Apoyo Nature Reserve. The volunteers who took care of him named him Heinz, and it even seems that he responds to his name. Heinz has been the subject of earlier blog entries. But one doesn't have to call him by his name to receive a visit from him. Heinz still makes a habit of dropping in on folks in the dining room without prior warning.

Photo by Anne Sutton.

His gregarious and engaging character is characteristic of his species and of all the birds of the family Corvidae, which includes the crows. Heinz is attracted to people, and also to shiny or colorful objects. He often drops in on someone to steal a pen cap, cigarette lighter, or anything metallic. He readily steals food from unattended plates and now that he is a few months old and independent, he has become so bold as to spar over the beans on one's fork as they are being transported from plate to mouth. He allows and even encourages petting, head-scratching, and all kinds of handling.



Photo by Anne Sutton.

Although one might find his antics entertaining, it is time that he stop visiting us and be a truly wild bird in our forest. Although he still begs for the favorite foods, cooked red beans and dog food pellets, he mostly feeds himself in the wild today. He has already joined a flock and spends most of his day with other birds. We saw him last week with the carcass of another bird, which was a good sign-he is a predator and that is what he is supposed to do, as gruesome as it may appear. He also found a wild pitahaya (Hylocereus costarricensis), an amazing fruit in its own right for humans! He appeared later with red stains all along his face and throat. He is doing fine and soon enough, he will brighten his plumage and begin to mate. 

Photo by Anne Sutton.

Laguna de Apoyo Nature Reserve is practically at the southern end of the range of this species, but they are abundant throughout the area. They entertain in the forest, traveling in very vocal social groups, active even in the early afternoon when other birds may be resting. Birdwatchers love them. We have enjoyed Heinz' company, but soon he will be just another hurraca in the forest for us. And of course, there will be yet another animal to save.

Saving Heinz was the work of volunteers at Estacion Biologica, all of whom executed other projects such as reforestation of degraded natural areas while caring for this chick. If you would like to volunteer with us, please let us know.

Click on the "escudo" to contact us.

The birds of Laguna de Apoyo Nature Reserve I: Resident birds

In this photography by our bird monitoring volunteer Joe Taylor, we see that the birds of Laguna de Apoyo Nature Reserve are truly esthetic beings. These photos were taken on mist netted birds while they were being processed by FUNDECI/GAIA staff, prior to returning to the wild. They show some of the wonderful details that we may never appreciate even as birdwatchers. Our technicians gather data on the bird populations by mist netting which is very important for conservation efforts, but we also enjoy the esthetic experience of admiring the birds from near. The birds were photographed in Laguna de Apoyo Nature Reserve, where all of them reproduce. We hope you enjoy them as much as we do.

Lesser Ground-Cuckoo (Morococcyx erythropygus) in Laguna de Apoyo Nature Reserve, Nicaragua. Photo by Joe Taylor.

Several cuckoo species are found in Laguna de Apoyo Nature Reserve, and they are not, at first sight, very similar birds. The Lesser Ground-Cuckoo (Morococcyx erythropygus) occupies degraded areas, and spends most of its time walking through low brush, on the ground. It is heard much more often than seen, giving a sound much like an insistent police whistle repeating. Folks here call it the "pajaro reloj" or the clock bird, because its call is reputed to be given on the hour, every hour. It nests on the ground, and its existence is threatened by domestic cats. Please don't bring cats into natural areas like this one! The Lesser Ground-Cuckoo is nothing short of spectacular when viewed up close.

Olive Sparrow (Arremonops rufivirgatus) in Laguna de Apoyo Nature Reserve, Nicaragua. Photo by Joe Taylor.

Dry tropical forest habitats usually have some grasses and other small-seeded annual plants in the many forest breaks, even when the forest is not heavily degraded by human use. Among the seed-eating birds in Laguna de Apoyo Nature Reserve is the Olive Sparrow (Arremonops rufivirgatus). The population here is not well-documented, its only reports to date being ours. We have recently spotted a nest with eggs, and two chicks hatched. This is another ground-nesting species, vulnerable to our beloved pet cats. Please keep your cats out of natural areas!


Female Long-tailed Manakin (Chiroxiphia linearis). Photo by Joe Taylor.

Immature male Long-tailed Manakin (Chiroxiphia linearis). Photo by Joe Taylor.

The Long-tailed Manakin (Chiroxiphia linearis) is the most commonly caught of all the bird species in our monitoring program. This is because we are located in prime habitat for them, in a sheltered area with lots of vegetation and food sources (they mostly eat fruit). The location is used for breeding, where males perform, quite literally, a song and dance to attract the females. Males perform the ritual in pairs, and the senior male gets the lady when she chooses the most attractive contestant. Males take up to four years to complete sexual maturity which is reflected in their plumage. We may catch as many as forty of this species in a single three-day period of mist netting.

Turquoise-browed Motmot (Eumomota superciliosa) and Blue-crowned Motmot (Momotus momota) in Laguna de Apoyo Nature Reserve, Nicaragua. Photo by Joe Taylor.

Among the emblematic birds of Nicaragua is the Turquoise-browed Motmot (Eumomota superciliosa), which is quite common throughout the Pacific region of the country. The Blue-crowned Motmot (Momotus momota) is considerably less common in most of the range. The subspecies found in Nicaragua has a black cap over the blue crown. Both motmot species nest in horizontal holes in dirt banks, and they catch flying insects on the wing as a principal component of their diet. They are both known as Guardabarrancos in Nicaragua, and the former is the national bird.

Dusky-capped Flycatcher (Myiarchus tuberculifer) in Laguna de Apoyo Nature Reserve, Nicaragua. Photo by Joe Taylor.

Lots of species of flycatchers are resident to Mesoamerica, and others migrate here from south or north. The flycatchers have bristly whiskers to help to guide their prey into the mouth. Shades of your aunt with the bristles on her chin, wanting to give you a kiss. It is not easy to distinguish them while birdwatching. Among the most common of flycatchers in Laguna de Apoyo Nature Reserve is the Dusky-capped Flycatcher (Myiarchus tuberculifer). This individual demands the last word, it appears.

Click on the "escudo" to contact us.

Mercury in the news in Nicaragua.

Mercury is used in a variety of ways in our society. Most of us "old folks" have silver fillings in our teeth which were implanted using mercury. The mercury slowly leaves the fillings and enters our body, perhaps to stay, embedded in bones and soft tissues. Gold and silver can be mined using mercury, as the mercury traps the precious minerals from dirt for easy separation.

Chlorine gas, an important industrial chemical, can be made using a technology which involves liquid mercury electrodes. This techology was once widespread, used to produce chlorine in factories throughout the United States. The US chemical company, Pennwalt, produced chlorine in Nicaragua using this technology during the 1960's, into the 1980's. The chemical plant was closed, and Pennwalt had long before left the scene and disappeared from existence.  But the remains of pollution from this plant are grievous. A small amount of research has been performed on the mercury in Nicaragua, mostly focussing on the impacts of the vast amounts (tens of tons) of mercury spilled over the years onto the ground along the shore of Lake Xolotlan (also known as Lake Managua), at what was once a chlorine production facility owned by Pennwalt.

Mercury also occurs in nature, and is often associated with volcanic activity. Nicaragua has lots of volcanoes. Estacion Biologica supported a study of mercury in the fish and water in Laguna de Apoyo, a volcanic crater lake that is considered not to be polluted with external sources of mercury, and Lake Xolotlan. We found that mercury levels in the water of Lake Xolotlan are extremely high, and a potential source is distant from the old Pennwalt site. Mercury levels are elevated in Lake Apoyo, likely from natural, volcanic sources, but these levels, much higher than lakes facing mercury fallout from coal-fired energy plants, are only one-tenth of the levels in Lake Xolotlan. Fish muscle tissue-the part we eat-in tilapia, guapote, and mojarra reached and exceeded in some cases, the indications for mercury in diet.

The article in Environmental Pollution can be found here., and a grafic is reproduced with the abstract below.

________________________________________________________________________________
This article appeared in today's El Nuevo Diario (13 JULY, 2011)

Golpe letal al Xolotlán

* Elemento químico que lanzó Penwalt en sus aguas han provocado que el cuerpo de agua sea irrecuperable, señala biólogo * CSJ justifica su fallo de 2010, y niega cualquier responsabilidad ambiental o laboral del BCIE * Concentraciones pasan de 0.73 a 4.48, valores muy por encima de los índices de tolerancia, y se está pasando al Cocibolca

La empresa Penwalt no solo cobró la vida de 24 trabajadores y afectó a 107 de ellos con daños irreversibles, sino que provocó una acumulación de 600 toneladas de mercurio en el lago Xolotlán.

Según explica el ecólogo y biólogo Kamilo Lara, el rango de concentración de mercurio detectado en el lago Xolotlán, ha variado de 0.73 a 4.48, según el sitio donde se han tomado las muestras.
Pero todos los sitios estudiados reportaron concentraciones por encima del valor establecido por las guías técnicas, que es de 0.1 microgramos de mercurio, el estándar permisible en un medio acuático para no provocar daños ambientales o sanitarios.
Los primeros niveles fueron encontrados a kilómetros de la planta, los segundos en las inmediaciones de la misma.
“Desgraciadamente, en esa época no existía la preocupación ni la legislación ambiental de hoy, por eso no manejamos las cifras de cuando la planta estaba operando. Pero si analizamos las variaciones en los niveles del contaminante, esto indica que el mercurio se está disolviendo en ciertas partes por el movimiento de las aguas, y focalizándose en las áreas cercanas a la planta”, explica Lara.
Según advierte el ecologista, esta dilución de mercurio que explica las variaciones encontradas en las distintas mediciones, es indicio de una preocupación mucho mayor.

Se está esparciendo y pasando al Cocibolca
“Es un hecho que el mercurio es una amenaza latente porque se está esparciendo del lago Xolotlán al Cocibolca a través del río Tipitapa, que sirve como vaso comunicante. Por eso las mediaciones están variando”
“Los valores encontrados en los sedimentos infiltrados por mercurio en el lago Xolotlán, fueron generados por las emanaciones atmosféricas de la industria Penwalt desde la década de los 80. En esa época, descubrimos que todas las pilas de la planta estaban llenas del material contaminante. Se limpiaron, se rasparon y se empacó el toxafeno (plaguicida) vencido en tanques de 55 galones, pero este fue un proceso que sólo abarcó el plaguicida que estaba acumulado dentro de la planta o infiltrado en el suelo, no en el lago, porque se suponía que el BCIE, al asumir el pasivo laboral, también iba a asumir la limpieza del lago, pero no lo hizo”
El mercurio puede existir enterrado a profundidad y ser liberado de los sedimentos hacia el agua. Este proceso depende del grado de acidez, el cual ejerce una marcada influencia en las posibilidades de disolución y movilización de este metal desde los sedimentos hasta la columna de agua.
“Los movimientos de mercurio en el lago a través de las variaciones en el ph (grado de acidez) están controlando los procesos de adherencia del mercurio a las piedras y granulaciones del suelo, y el desprendimiento del mismo, explicando su esparcimiento al Cocibolca”, explica Kamilo Lara

Penwalt también afectó Miraflores
Según el ecólogo Kamilo Lara, la presencia de mercurio en el litoral del lago, probablemente se deba a la proximidad  con la Bahía Sur, donde se dio una contaminación mercurial en el sitio conocido como Bahía de Miraflores, donde se derramaban directamente los desechos tóxicos.
Aquí se reportaron concentraciones de 7.3 a 9.2 microgramos
“Cuando la Penwalt quebró y el Banco Centroamericano de Integración Económica (BCIE) asumió la deuda y se quedó con los activos de la fábrica, estos activos ni siquiera se pudieron utilizar, ni vender  como chatarra, porque poseían una contaminación tremenda por el peligroso Toxafeno, un plaguicida encontrado, y por  los restos de mercurio”, señala Lara

Peligrosidad del químico
Según explica el ecólogo Kamilo Lara, cuando el mercurio cae al agua, se adhiere con facilidad a las proteínas que están en el cuerpo de los peces, fijándose en el cuerpo de cualquier animal que coma alimentos contaminados con mercurio. De esta forma, cuando el ser humano consume pescado contaminado, la sustancia pasa al cuerpo de las personas.
“Esto provoca diversas enfermedades, entre ellas, trastornos neurológicos muy complejos, de tal manera que a medida que se va concentrando el mercurio en el cuerpo humano las afecciones son mayores. Una vez que el mercurio atraviesa las membranas cerebrales ya no puede ser eliminado, y es por ello que la persona presenta síntomas neurológicos severos llamados Síndrome de Minamata”, añade Lara.

CSJ justifica su fallo
En la sentencia emitida por la CSJ (Corte Suprema de Justicia) el 20 de octubre de 2010, donde se negó el recurso de amparo a los 107 trabajadores de la Penwalt, esta aseguró que el Banco Centroamericano de Integración Económica no tenía responsabilidad ambiental ni laboral.
Según versa en la sentencia número 434, expediente n.º 216-02, inscrita por la Secretaría de la Sala de lo Constitucional de la Corte Suprema de Justicia:
“Las facultades de la Corte no pueden ir más allá de aquellas personas que hayan causado el daño ambiental y laboral, y en el presente caso fue la empresa Penwalt, al haber depositado grandes cantidades de mercurio en la orilla del lago Xolotlán, y no el Banco de Integración Económica, quien adquiere los bienes de la empresa por medio de ejecución judicial ante un incumplimiento de contrato mutuo con Garantía Prendaría e Hipotecaría por un préstamo de 4 millones de dólares”.
Al respecto, el abogado Álvaro Leiva Sánchez, Delegado de Derechos Humanos por la Confederación de Unidad Sindical y la Confederación Sindical de Trabajadores de las Américas, asegura que esto es una burla al sistema judicial y a los derechos de los trabajadores.
“Cuando el banco tomó los pasivos de la empresa asumió sus deberes y obligaciones, así que tiene que pagar la indemnización por daños y perjuicios y responder con acciones contundentes ante los daños ambientales. La deuda que tenía pendiente con la Penwalt no lo exime de responsabilidad, y este fallo de la Corte es una vergüenza para un sistema judicial que en vez de tutelar el derecho de los trabajadores los violenta”, asegura Leiva.

Click on the "escudo" to contact us. 

Environ Pollut. 2006 Jun;141(3):513-8. Epub 2005 Dec 9.

Mercury in fish from two Nicaraguan lakes: a recommendation for increased monitoring of fish for international commerce.

McCrary JK, Castro M, McKaye KR.

Source

University of Central America, Apdo. 69, Managua, Nicaragua. jmccrary2@yahoo.com

Abstract

We measured total mercury concentrations in water and fish of Lake Managua and Lake Apoyo. Water mercury concentrations were 10-fold higher in Lake Managua than in Lake Apoyo, although differences in mercury concentration in the most common native fish were not significant. One-fourth of the commercially fished tilapia in Lake Managua exceeded maximum recommended mercury levels for consumption among pregnant women and other at-risk groups, although bioavailability to fishes was lower than in previously studied sites in Brazil and Western Maryland. The lower bioavailiability may present important information for management options to reduce mercury exposure to fishes and humans. We recommend closer mercury monitoring among freshwater fish destined for international commerce.

Howler monkey photography by Mark de Graaf

These photos of a howler monkey family were taken in the yard of Estacion Biologica in Laguna de Apoyo Nature Reserve, Nicaragua, by a student of the Laguna de Apoyo Spanish School, Mark de Graaf. Thank you, Mark!

Estacion Biologica is executing a study of monkey populations in Laguna de Apoyo Nature Reserve. We need volunteers, students, and scientists. Would you like to participate? Please let us know.

Click on the "escudo" to contact us.