Smithsonian Science » zoology

New frog species pose challenge for conservation project in Panama

John Barrat — Thu, 29 Jul 2010 12:06:04 +0000

The recent discovery of what may be three new frog species by researchers in Panama illustrates the hope and fear encountered daily by the Panama Amphibian Rescue and Conservation Project. The discoveries lead to hope that project researchers can save these animals from a deadly fungus killing frogs worldwide and the fear that many species will go extinct before scientists even know they exist.

Photo right: One of the three potentially new species appears to be a robber frog, genus Craugastor, shown here. The unique skin folds on its arms and feet distinguish it from other closely related species. Robber frogs are especially susceptible to chytrid. (Photos by Brian Gratwicke, Smithsonian Conservation Biology Institute)

“It is disturbing to witness the disappearance of species that some of us only recently described and even more devastating to lose those we know are probably new species,” said Roberto Ibáñez, local director of the project and a scientist at the Smithsonian Tropical Research Institute, one of nine project partners, including the Smithsonian’s National Zoo. “Scientists are just starting to investigate the ecological impact of the loss of amphibians, and while we’re aiming to preserve some of these species, we already know it will be impossible to save them all.”

Nearly one-third of all amphibian species globally are at the risk of going extinct. The rescue project aims to save more than 20 species of frogs in Panama, which is one of the world’s last strongholds for amphibian biodiversity. While the global amphibian crisis is the result of habitat loss, climate change and pollution, the deadly amphibian chytrid fungus is likely at least partly responsible for the disappearances of 94 of the 120 frog species that are thought to have gone extinct since 1980.

Photo left: Two of the three potentially new species is a rain frog from the genus Pristimantis. The species pictured here has a bright red stomach that is uncharacteristic for rain frogs, earning it the nickname “red tomato.”

Although it can take years to determine that a species is new to science, project researchers have identified some telltale signs indicating that the three species found in eastern Panama are, indeed, new. The first two are rain frogs from the genus Pristimantis. One of these species has a bright red stomach that is uncharacteristic for rain frogs, earning it the nickname “red tomato.” The second species is much larger than any known Pristimantis in the region. The third frog species appears to be a robber frog, genus Craugastor, but unique skin folds on its arms and feet distinguish it from other closely related species. Robber frogs are especially susceptible to chytrid.

A new study by Andrew Crawford, a STRI research associate, and colleagues reveals that many frog species at a site in western Panama have gone extinct before researchers knew they existed. The project’s three potentially new species are evidence of the same story playing out right now in the mountains of eastern Panama. Researchers have brought a handful of animals of each species back to the Summit Municipal Park in Panama City, Panama, where the project has turned used shipping containers into amphibian rescue pods.

“We are doing our best to salvage what we can, but we are in urgent need of funding to build capacity in Panama to house all of these chytrid refugees,” said Brian Gratwicke, a National Zoo research biologist and the international coordinator for the Panama Amphibian Rescue and Conservation Project. “The species is the basic unit of conservation, so these discoveries are rewarding, but that comes with the daunting responsibility of deciding how we look after them. We already have a huge job, and it just gets bigger with every discovery.”

Now project scientists will use collections of frogs from the same region at the Smithsonian’s Natural History Museum and elsewhere to determine if these species are genuinely new or if they have already been discovered (or “described”) elsewhere. The project has also collected tissue sample to use DNA testing to map out the animals’ closest genetic relatives.

“Finding a new species is like discovering a new Pablo Picasso,” said Gratwicke. “Each species is a priceless creation painted with the brushstrokes of natural selection on the canvas of DNA and has something of value to offer. We might not know how they’re valuable to us right now, but if they go extinct, we lose the opportunity to learn what secrets they hold.”

The mission of the Panama Amphibian Rescue and Conservation Project is to rescue amphibian species that are in extreme danger of extinction throughout Panama. The project’s efforts and expertise are focused on establishing assurance colonies and developing methodologies to reduce the impact of the amphibian chytrid fungus so that one day captive amphibians may be re-introduced to the wild. Project participants include Africam Safari, Autoridad Nacional del Ambiente, Cheyenne Mountain Zoo, Defenders of Wildlife, El Valle Amphibian Conservation Center, Houston Zoo, Smithsonian’s National Zoological Park, Smithsonian Tropical Research Institute, Summit Municipal Park and Zoo New England.

New Zealand Embassy donates kiwi pair to National Zoo Breeding Science Center

John Barrat — Mon, 26 Jul 2010 17:53:48 +0000

Kiwis come to National Zoo. The Smithsonian’s National Zoo will be using a new kiwi pair donated by the New Zealand Embassy to establish a breeding science center. Both birds came from the Ngati Hine people in New Zealand. Adding these animals to the genetic pool in North America is a rare and valuable opportunity. This pair came with another pair that will continue on to Germany and one bird that went to the San Diego Zoo. Kiwis are native to New Zealand and have been there for more than 60 million years, making them New Zealand’s most ancient bird. (Photo by Mehgan Murphy)

Introducing the parasitic dinoflagellate: Tintinnophagus acutus

John Barrat — Fri, 25 Jun 2010 16:51:54 +0000

In the microscopic world of marine protists, many species drift in the ocean currents unstudied and nameless. This is no longer the case for the parasitic dinoflagellate Tintinnophagus acutus. SERC plankton ecologist Wayne Coats recently finished an extensive description of the organism and thus earned naming rights.

Photo right: Tintinnophagus acutus dinospore, with a flagellum.

Of the approximately 2,000 known species of living dinoflagellates, about 150 are parasitic. These organisms can alter the marine food web, in some cases destroying prey that consumers like copepods and larval fish rely upon. Coats first spotted T. acutus in the 1980s, in plankton samples he had collected from the Chesapeake Bay. Through his microscope, he noticed a ciliate being edged out of its lorica (shell) by a dinoflagellate. It looked different from others he had observed.

Describing a species is a serious undertaking. In the case of T. acutus, Coats and his collaborators documented its microscopic life cycle, conducted extensive DNA analysis and unearthed scientific papers dating back to 1873—when parasitic dinoflagellates were first noted by German scientist Ernst Haeckel.

Much of Coats’ work involved understanding, questioning and clarifying various accounts of similar dinoflagellates that have been written over the years. He read studies published in French, German and English. This thorough research resulted in more than the introduction of T. acutus: it provided new understanding of the evolutionary relationships among parasitic dinoflagellates and it better defined their position within the dinoflagellate lineage of the tree of life.

Photo left: The host lorica (shell) contains the host ciliate Tintinnopsis cylindrica (upper part), which is being consumed by the parasitic dinoflagellate Tintinnophagus acutus (bottom, yellow). (Wayne Coats photos)

Protist phylogeny has never been Coats’ primary focus. T. acutus is the second species that he has named and described. This fall Coats will retire from SERC; he says he expects to have time to describe a few more species of parasitic dinoflagellates. –Tina Tennessen

Transmitters unveil long-distance movements of orchid bees

John Barrat — Thu, 27 May 2010 17:42:51 +0000

In their daily search for food, blue-green orchid bees zip through increasingly scarce patches of tropical forest pollinating rare flowers. Now, for the first time ever, researchers at the Smithsonian Tropical Research Institute are able to track the routes of these creatures by gluing tiny transmitters to the backs of individual bees. The data they are collecting is yielding new insight into the role bees play in tropical forest ecosystems.

“When people disturb and destroy tropical forest they disrupt pollination systems,” says entomologist David Roubik, senior staff scientist at the Tropical Research Institute. “Now we can track orchid bees to get at the distances and spatial patterns involved in pollination—vital details which have completely eluded us in the past.”

The team trapped 17 iridescent blue-green orchid bees called Exaerete frontalis –a species common in the rainforest. “These bees easily carry a 300-milligram radio transmitter glued onto their backs,” says Martin Wikelski, director of the Max Planck Institute of Ornithology and a research associate at the Smithsonian. “By following the radio signals with a hand-held antenna, we have discovered that male orchid bees spend most of their time in small core areas, but will take off and visit areas farther away.

One male even crossed over the shipping lanes in the Panama Canal, flew 5 kilometres, and returned to Barro Colorado Island a few days later. Such long distance flights, the researchers say, support the claim that bees are major agents of gene flow, connecting widely-dsipersed orchids or other plants which they alone pollinate, over fragmented landscapes and for an extended time. This study proves that “bees are key evolutionary players in allowing orchids and other tropical plants to evolve into diverse taxa that are each spatially rare and thus require long-distance pollination,” the researchers write.

In the past, researchers have struggled to determine the distances that bees travel by following individuals marked with paint, or using radar, which doesn’t work well when trees are in the way. “Carrying a transmitter may reduce the distance that the bees travel. But even if the flight distances we record are the minimum distances that these orchid bees can fly, they are impressive, long-distance movements,” said Roland Kays, curator of mammals at the New York State Museum and a STRI research associate. “These data help to explain how the orchids these bees pollinate can be so rare.”

The Smithsonian Tropical Research Institute, the U.S. Environmental Protection Agency, the New York State Museum and the National Geographic Society all provided support for this study. Its co-authors are affiliated with the University of Arizona, Tucson, Cornell University, EcolSciences, Inc. and the New York State Museum.

May Smithsonian symposium marks research contributions of scuba

John Barrat — Wed, 19 May 2010 12:16:04 +0000

Organisms are best understood by observing them directly in their habitat. For marine organisms, however, their salt water surroundings makes this a challenge to scientists. Scuba has changed that. For example, initially coral was believed to be a plant. Eighteenth-century scientists used microscopes to classify coral as an animal, but it was not until scuba was developed that researchers were able to study coral in its natural habitat for long periods of time. This led to a much clearer understanding of coral, its communities and ecosystems.

Right: Smithsonian Scientific Diving Officer Michael Lang in Florida.

Allowing scientists to stay underwater for extended periods has made scuba equipment an invaluable tool for the study of marine and freshwater environments. Since its development in 1943, scuba (self-contained underwater breathing apparatus) has enabled researchers to dive longer and deeper and closely study millions of underwater species and their vibrant ecosystems.

To mark scuba’s important contribution to underwater science, the Smithsonian Institution is convening dozens of scientists on May 24 – 25 at the National Museum of Natural History for a special symposium: “Research and Discoveries: The Revolution of Science through Scuba.” Open to the public, anyone wishing to attend this symposium should register online at the Web site: www.si.edu/sds/

Photo left: Brown elegance coral

“Without scuba our dive times would be restricted to the few minutes we can hold our breath, clearly not long enough to make scientific observations or collect samples,” says Michael Lang, director of the Smithsonian’s Marine Science Network and the Smithsonian’s Science Diving Program. “With thorough entry-level training, scientific scuba is a simple enough tool to enable its effective and safe use at many remote research sites.”

Photo right: A Smithsonian dive team. (Photo by Dan Miller)

Scuba is not a finished product, however. As technological advancements are made, scuba will continue to grow and be an even greater resource to science and discovery. “As our knowledge of decompression sickness increases and engineering solutions for scuba regulators and dive computers evolve, the envelope of our working window in the underwater world will likely expand, opening up new depths and habitats for research and exploration,” Lang says.

Net survey: For quarter century, scientists have been counting creatures traveling Chesapeake Bay tributary

John Barrat — Thu, 06 May 2010 12:58:53 +0000

For fish, crabs and other creatures living in the Chesapeake Bay, the many creeks, rivers or subestuaries that feed the Chesapeake are enticing avenues to explore for food and refuge. These tributaries also provide important nursery and spawning habitat for many of the Bay’s aquatic residents. More than 25 years ago, researchers at the Smithsonian Environmental Research Center’s Fish and Invertebrate Ecology Lab began taking weekley surveys of the species that make their way in and out of Muddy Creek. This waterway flows through the center’s grounds in Edgewater, Md., and feeds into the Rhode River, which then feeds into the Chesapeake Bay.

View Muddy Creek and the Rhode River in a larger map

To survey the animals swimming up and down Muddy Creek, researchers use a fish weir—an expanse of nets, gates and boardwalks—that temporarily blocks aquatic traffic. Once a week, the researchers close the weir, set out the nets and identify and count all the species that get trapped. They began collecting data in 1983.

This type of fine-scale surveying, done on a weekly basis, is rare. It’s even more unique to have such long-term data. Many ecological studies are funded for just a few years at a time. These short time frames make it difficult for scientists to observe changes and patterns in species populations and composition.

In honor of the 2010 U.S. Census, staff at the Smithsonian Environmental Research Center have created this slide show of a recent spring survey. The salinity on this April day was fairly low and nearly a dozen golden shiners (a freshwater minnow) were caught along with several estuarine-resident and a few diadromous (fish that migrate between fresh and saltwater) species. Among the highlights: a sizeable snapping turtle, many white perch in spawning condition, juvenile American eels and a parasite.

Human activity and environmental conditions can affect which species are swimming in Muddy Creek. The water is brackish and salinity levels change seasonally and from year to year. During winter and early spring, when freshwater flow is usually the highest, researchers will generally catch more freshwater species like bluespotted and banded sunfish–-two protected species in Maryland. During periods of high salinity, researchers can catch many species indicative of the higher saline lower Bay such as red drum, spotted sea trout and Spanish mackerel. –Tina Tennessen

Shipping industry sends help as project in Panama tackles amphibian crisis

John Barrat — Fri, 23 Apr 2010 13:34:26 +0000

As a disease known as amphibian chytrid fungus continues to wipe out amphibian species worldwide, frogs in Panama are finding a safe haven in a seemingly unlikely spot—between the metal walls of shipping containers once used to transport ice cream, strawberries, coffee beans, flowers and pharmaceuticals. Two of six refrigerated containers to be donated by the shipping company Maersk Line arrived this week at Summit Municipal Park in Panama City, Panama, where the Smithsonian Institution and partners are working to save amphibians in imminent danger of extinction.

Photo right: The limosa harlequin frog (Atelopus limosus) is one of 54 species that Amphibian Ark has identified as a priority rescue species for the Panama Amphibian Rescue and Conservation Project. (Click to enlarge)

“Each container provides us with critical space to house animals that may represent the last chance for the survival of their species,” said Brian Gratwicke, a National Zoo research biologist and the international coordinator for the Panama Amphibian Rescue and Conservation Project. “The containers are now self-contained ‘amphibian rescue pods’ that have been specially modified to control the climate and keep diseases out.”

The rescue pods will be part of the project’s Amphibian Rescue Center at Summit Municipal Park, which will also include a lab with a quarantine facility. After frogs are collected in the field, they will be quarantined for 30 days before being moved to the rescue pods that will serve as their new home. In addition to the two containers that are now in Panama, Maersk Line has agreed to donate two containers per year for the next two years to the project, for a total of six. Shipping company APL has also donated one container this year. Each container offers 995 cubic feet of space to house these animals. The seven together will more than double the amount of captive space the project currently has in Panama to safeguard endangered amphibians.

Photo left: Shipping company Maersk Line has agreed to donate up to six used shipping containers similar to this one to the Panama Amphibian Rescue and Conservation Project. The containers will serve as rescue pods for endangered amphibians.

“Maersk Line’s support of the amphibian rescue project is aligned with our long-term focus on sustainability,” said Mike White, head of Maersk Line’s North American organization. “Although we are pleased to donate these containers, the more valuable contribution is our expertise and resources. Our team’s assistance with documentation and transportation allows Brian’s group to concentrate on the overall effort.”

Amphibian Ark, an organization that mobilizes support for ex-situ (“out-of-the-wild”) conservation, has identified 54 amphibian species as rescue species for the Panama Amphibian Rescue and Conservation Project. At least 198 amphibian species live in Panama, of which 70 are listed as “critically endangered,” “endangered” or “data deficient” by the International Union for Conservation of Nature. Amphibian Ark estimates that about 500 amphibian rescue pods are needed to save the world’s 500 critically endangered amphibian species. Buying, outfitting and installing a single container costs about $50,000.

Photo right: Each shipping container offers 995 cubic feet of space to safeguard endangered species. (Photos by Brian Gratwicke)

“This requires an amount of resources that is insurmountable for the amphibian rescue community,” said Kevin Zippel, Amphibian Ark’s program director. “With a relatively small investment, the shipping industry has made a huge impact on one of the greatest conservation challenges that humanity has ever faced. We are currently seeking additional contributions of this kind.”

The mission of the Amphibian Rescue and Conservation Project is to rescue amphibian species that are in extreme danger of extinction from amphibian chytrid disease sweeping through Panama. The project’s focus is on developing appropriate technologies to control the amphibian chytrid fungus, so that one day captive amphibians may be reintroduced to the wild. Project participants include Africam Safari, ANAM (Autoridad Nacional del Ambiente), Cheyenne Mountain Zoo, Defenders of Wildlife, Houston Zoo, Smithsonian’s National Zoological Park, Smithsonian Tropical Research Institute, Summit Municipal Park and Zoo New England.

Thepytus carmen, a newly described species of butterfly from Brazil

John Barrat — Tue, 13 Apr 2010 12:49:41 +0000

Thepytus carmen, a newly described species of butterfly from Brazil, was recently named in memory of Carmen Lúcia Buck in recognition of the gracious support of science that she and her husband Peter have provided to the Smithsonian Institution’s National Museum of Natural History. Described by Smithsonian entomologist Robert K. Robbins and Marcelo Duarte, Museum of Zoology, University of São Paulo. (Illustration by Vichai Malikul)

A well-defended territory is what some female hummingbirds find most attractive in a mate

John Barrat — Wed, 31 Mar 2010 17:20:21 +0000

When it comes to attracting a mate, flowers and sweets often do the trick—even for one of the world’s smallest birds—the purple throated carib, a hummingbird species native to the mountainous islands of the Eastern Caribbean. Scientists recently discovered that it is in the best interest of male purple-throated caribs to defend and maintain a territory with a high density of nectar-producing flowers. Why? Because it is the quality of this territory—rather than flashy plumage or elaborate courtship displays—that attracts the most females.

Image right: A male purple-throated carib perches on a Caribbean heliconia plant. Click to enlarge. (Photo by John Kress)

John Kress, a botanist at the Smithsonian’s National Museum of Natural History, and Ethan Temeles, an ornithologist and biology professor at Amherst College in Massachusetts, have spent several years researching purple throated caribs (Eulampis jugularis) in the wild on the island of Dominica. What they observed was unique among all bird species: successful male caribs maintained and defended territories with nectar supplies that were two to five times greater than their daily needs and also isolated part of their crop for the exclusive feeding rights of visiting females. The key to this female-only feeding area was the presence of heliconia flowers.

“This is the first time such behavior has ever been observed in a bird species,” said Kress. “Not only is the male defending a huge territory from competing males, but he’s also defending a big chunk of it exclusively for females who he is trying to attract as potential mates. He is farming the nectar for these dual purposes.”

Image left: A female purple-throated carib (Photo by Ethan Temeles)

Male and female purple throated caribs are alike in plumage, but males are considerably larger and have longer wings than females. Females, however, have bills that are 20 percent longer and 30 percent more curved than the bills of the males, meaning that they are physically able to feed from flowers that males cannot. This is also known as “sexual resource partitioning” and for the purple throated carib it applies to two species of Heliconia, a primarily neotropical genus of plants. Male caribs feed from the Caribbean heliconia (Heliconia caribaea), while females feed primarily from the lobster claw heliconia (Heliconia bihai).

This close correspondence between the physical traits of the two different heliconia flowers and the bill morphology of each sex of purple-throated carib strongly suggests that the process of coevolution (the evolution of two or more species that interact closely with one another, with each species adapting to changes in the other) is the cause of this fit between the birds and the flowers. Furthermore, this process is strongly reinforced by the fact that the different energy requirements of the male and female carib are uniquely matched by the energy rewards in the nectar of their respective heliconia flowers.

Image right: A male purple-throated carib sips nectar from a Caribbean heliconia plant. (Photo by Ethan Temeles)

The scientists report that a female’s choice of a male depends on the nectar supplies within his territory, which in turn depended on his prevention of nectar losses to competing male purple-throated caribs and other nectar feeding intruders.

“One of the most important aspects of maintaining an abundant nectar crop for the male carib is keeping intruders out,” Temeles said. “We found that males that were most successful at defending their territories from intruders also were the ones that were most successful at dominating neighboring males and at feeding on neighbors’ territories.”

The male’s reward for spending the time and energy in defending his territory was, of course, the attraction of potential mates. Temeles and Kress observed that the rates of female intrusions to feed on defended territories were highest in late morning and early afternoon, at times when the amount of nectar in undefended plants was lowest. “Once the females are in the territories they are allowed to “sip from the male’s wine cellar.” If she likes what she is sampling, then mating takes place,” Temeles said.

Kress and Temeles plan to extend their studies to other islands in the Eastern Caribbean to test how this plant-pollinator system has evolved in different regions and in different ecosystems. —Johnny Gibbons

For sweat bees, being social builds a more developed brain

John Barrat — Thu, 25 Mar 2010 12:52:41 +0000

Females of the tropical sweat bee Megalopta genalisa exhibit a very primitive form of social behavior. Either a bee lives as a solitary queen, going out from her nest to forage for her own food, or she can be a social queen–a stay-at-home mom. In that case, one of her daughters goes out to forage for her. The daughter’s ovaries don’t develop, and she never leaves her mother to start her own colony.

Recently, scientists at the Smithsonian Tropical Research Institute in Panama discovered that the brain region responsible for learning and memory is larger in the social queens than in the solitary queens of this species. Their study is the first comparison of the brain sizes of social and non-social individuals of the same species.

Image right: A tropical sweat bee, Megalopta genalisa, in her nest.

“The idea is that to maintain power and control in groups you need more information, so the bigger the group, the bigger individuals’ brains need to be.” says William Wcislo, Smithsonian staff scientist.

“It was surprising to us that even though the social queens don’t have bigger brains overall, the fact that the area associated with learning and memory–the mushroom body–was more developed in the social queens than in the solitary bees suggesting that social interactions are cognitively challenging, as predicted by the social brain hypothesis,” said Adam Smith, postdoctoral fellow at STRI. “It’s interesting to see that a characteristic like brain development changes so immediately, even with this simple mother-daughter division of labor.”

This study was done in the Smithsonian Tropical Research Institute’s new insect neurobiology laboratory, built to take advantage of diverse tropical insect groups with a variety of brain sizes to understand how brain size and behavior are related

These results were published recently online in the journal Proceedings of the Royal Society B.