Tag Archives: migration

Migration No Longer Best Strategy for Yellowstone Elk

By Guest PostJune 5, 2013Naturearthur middleton, best strategy, dwindling phenomenon, ecological changes, female migratory elk, matthew kauffman, migration, migratory elk, natural experiment, predator management, rocky mountain elk, U.S. Geological Survey, university of wyoming, wgfd, wildlife, yellowstone, yellowstone elk, yellowstone national park, yellowstone wolf reintroduction

LARAMIE, Wyo. — Migratory elk are coming back from Yellowstone National Park with fewer calves due to drought and increased numbers of big predators – two landscape-level changes that are reducing the benefits of migration with broader implications for conservation of migratory animals, according to a new study published in the journal Ecology.

The new study by the Wyoming Cooperative Fish and Wildlife Research Unit – a joint program involving U.S. Geological Survey, the University of Wyoming, and the Wyoming Game and Fish Department, describes a long-term decline in the number of calves produced annually by the Clarks Fork herd, a population of about 4000 elk whose migrants travel annually between winter ranges near Cody, Wyoming and summer ranges within Yellowstone National Park. Migratory elk experienced a 19 percent depression in rates of pregnancy over the four years of the study and a 70 percent decline in calf production over 21 years of monitoring by the WGFD, while the elk that did not migrate, known as resident elk, in the same herd experienced high pregnancy and calf production and are expanding their numbers and range into private lands outside of the park. (more…)

Behaviour of seabirds during migration revealed

By Guest PostMay 6, 2013Natureanimal behavior, anthropogenic pressure, behaviour of seabirds, behavioural states, centre for mathematics, complex data series, computational analyses, conservation concern, environmental, environmental conditions, ethoinformatics, flight, geolocators, gps tracking, lightweight gps loggers, manx shearwater, migration, migration data, new method, patterns of foraging, puffinus puffinus, rest, robin freeman, royal society, small seabird, south america, south eastern brazil, species, tracking technologies, ucl, uk birds, university of oxford, western atlantic

The behaviour of seabirds during migration – including patterns of foraging, rest and flight – has been revealed in new detail using novel computational analyses and tracking technologies.

Using a new method called ‘ethoinformatics’, described as the application of computational methods in the investigation of animal behaviour, scientists have been able to analyse three years of migration data gathered from miniature tracking devices attached to the small seabird the Manx Shearwater (Puffinus puffinus). (more…)

Aztec Conquest Altered Genetics among Early Mexico Inhabitants, New DNA Study Shows

By Guest PostFebruary 3, 2013Science1395 ad, adna, alter, ancient dna, anthropological research, archeological dig, austin, aztec conquest, aztec empire, aztec imperialism, capital, case of xaltocan, colonization, dna study, early mexico inhabitants, exodus, genetic evidence, genetic impact, genetic shift, genetic transition, genetics, historical events, imperial conquest, jaime mata míguez, lisa overholtzer, mesoamerican populations, mexican city state, migration, mitochondrial adna, otomi inhabitants, otomi people, otomi population, otomi skull, post conquest era, pre aztec, university of texas, washington state university, wichita state university, xaltocan, xaltocan dig site, xaltocan households

AUSTIN, Texas — For centuries, the fate of the original Otomí inhabitants of Xaltocan, the capital of a pre-Aztec Mexican city-state, has remained unknown. Researchers have long wondered whether they assimilated with the Aztecs or abandoned the town altogether.

According to new anthropological research from The University of Texas at Austin, Wichita State University and Washington State University, the answers may lie in DNA. Following this line of evidence, the researchers theorize that some original Otomies, possibly elite rulers, may have fled the town. Their exodus may have led to the reorganization of the original residents within Xaltocan, or to the influx of new residents, who may have intermarried with the Otomí population. (more…)

Genetic Patterns of Deep-Sea Coral Provide Insights into Evolution of Marine Life

By Guest PostNovember 17, 2012Environment, Natureancient, barnacles, biodiversity, biogeography, bivalves, bryozoans, bubblegum coral, canyons, circulation model, climate change, continental slopes, coral, cryptic species, csiro, deep sea coral, early pliocene, eastern north pacific, Epoch, fjords, gastropods, gene flow, genetic diversity pattern, geological features, global warming, historical pattern, hypothesis, juan sanchez, late-miocene, marine life, marine organism, migration, migration pattern, moss animals, niwa, north atlantic, ocean acidification, oceanic circulation, organism, paragorga arborea, pattern, period, ph, red algae, santiago herrera, sea stars, seagrass, seamounts, South Pacific, southern indian, species, spiny dogfishes, timothy shank, trans arctic interchange, western north pacific, whoi

Patterns Also Shed Light on How Environmental Disturbances Affect Aquatic Organisms

The ability of deep-sea corals to harbor a broad array of marine life, including commercially important fish species, make these habitat-forming organisms of immediate interest to conservationists, managers, and scientists. Understanding and protecting corals requires knowledge of the historical processes that have shaped their biodiversity and biogeography.

While little is known about these processes, new research described in the journal Molecular Ecology helps elucidate the historical patterns of deep-sea coral migration and gene flow, coincident with oceanic circulation patterns and events. The investigators propose a scenario that could explain the observed evolutionary and present-day patterns in certain coral species. The findings can help scientists determine how climate change and other global processes have affected ocean habitats in the past and how they might do so in the future. (more…)

NASA Maps How Nutrients Affect Plant Productivity

By Guest PostNovember 3, 2012Environmentamazonia, biogeochemical cycles, boreal, boreal forest, carbon cycle, carbon dioxide, data, earth, ecosystem, eleanor blyth, eurasian forest, fertile earth, fertilization, global, grasslands, grayson badgley, greenhouse gas, growth, hawaii, jet propulsion, josh fisher, laboratory, level, maps, migration, model, NASA, nitrogen, North America, north american, nutrient, ozone mapping, palo alto, pasadena, phosphorus, plant, satellite, savannas, shrublands, soil, spectrometer, stanford university, terra spacecraft, terrestrial biosphere, total, trees, tropical forest, validation site, vegetation, vegetation productivity

PASADENA, Calif. – A new analysis led by NASA’s Jet Propulsion Laboratory, Pasadena, Calif., has estimated how much the growth of plants worldwide is limited by the amount of nutrients available in their soil. The maps produced from the research will be particularly useful in evaluating how much carbon dioxide Earth’s ecosystems may be able to soak up as greenhouse gas levels increase.

A research team led by JPL research scientist Josh Fisher used 19 years of data from NASA, National Oceanic and Atmospheric Administration and international satellites to assess the maximum possible growth of vegetation all over the world based upon available water and light conditions. The scientists then cross-compared that potential maximum with observed vegetation productivity as measured by satellites. This is the first time such an analysis has been conducted. (more…)

Tracking Fish Through a Coral Reef Seascape

By Guest PostSeptember 4, 2012Environment, Naturecoastal seagrass, coastal wetland, coral reef, dream divers, ear bones, ehrenbergs snapper, fish, food web, functional connectivity, gas chromatography, isoscape, isotope signature, juvenile, kelton mcmahon, king abdullah, lutjanus ehrenbergii, mangrove habitat, marine environment, michael berument, migration, northern coast, nursery habitat, ocean, offshore island, offshore reef, otoliths, plasticity, record, red sea, reef ecosystem, reef fish, remediation, saudi arabia, scientist, simon thorrold, subtropical water, tree rings, tropical habitat, tropical seascape, university, whoi

Ear-bone ‘tree rings’ provide evidence of connectivity

Ocean scientists have long known that juvenile coral reef fishes use coastal seagrass and mangrove habitats as nurseries, later moving as adults onto coral reefs. But the fishes’ movements, and the connections between different tropical habitats, are much more complex than previously realized, according to a study published September 3 in Proceedings of the National Academy of Sciences. The findings have important implications for management and protection of coral reefs and other marine environments.

A number of studies have demonstrated a strong relationship between the presence of coastal wetlands and offshore fish abundance and fisheries yield, but it has proved difficult to develop quantitative assessment of habitat use by fish or their movement among different habitats. “The rationale for this study,”says Simon Thorrold, a biologist at Woods Hole Oceanographic Institution (WHOI), “was to determine the relative importance of different nursery habitats to reef fishes that spend their adult lives on coral reefs but may spend at least part of their juvenile residency elsewhere.” (more…)

Highway Through Amazon Worsens Effects of Climate Change, Provides Mixed Economic Gains

By Guest PostJune 10, 2012EnvironmentAmazon, Amazon rainforest, amazonian, amazonian university, biodiversity hot spot, Bolivia, brazil, brazilian families, carbon emission, climate change, environmental change, highway, interoceanic highway, jeffrey hoelle, migration, pando, peru, plant, population growth, rainforest, rio 20, rubber tappers, south america, southwestern amazon, stephen perz, university of florida, wildlife

GAINESVILLE, Fla. — Paving a highway across South America is providing lessons on the impact of road construction elsewhere.

That’s what a University of Florida researcher and his international colleagues have determined from analyzing communities along the Amazonian portion of the nearly 4,200-mile Interoceanic Highway, a coast-to-coast road that starts at ports in Brazil and will eventually connect to ones in Peru. (more…)

Counting Horseshoe Crabs

By Guest PostMay 17, 2012Nature, Sciencecensus, crab line, crab population, delaware bay, dover, eadoh reshef, fertilization, field research, horseshoe crab, joanna york, jonathan dinman, kayla krenitsky, marine science, megan nogan, migration, pvc pipe, st jones reserve, tammy beeson, teresa messmore, university of delaware, will goldman

Marine science majors conduct field research with horseshoe crab census

Wearing sneakers and rain boots, University of Delaware freshmen got their feet wet as marine biologists recently while counting horseshoe crabs along the Delaware Bay. The students participated in a monitoring effort to gain firsthand experience in field research with their fellow marine science majors.

“Where else can you go on a Saturday night to count horseshoe crabs?” freshman Will Goldman said. (more…)