Virginia Tech's Bill Hopkins holds a female wood duck, as part of the studies he and his colleagues are conducting to determine how the physiology and behavior of female amphibians, turtles and birds affect their offspring, and the consequences these interactions may have for population health. See more images and read more about wood ducks.
Credit: Photo by Kate Hasapes; courtesy Bill Hopkins, Virginia Tech
Gail Patricelli, an animal behaviorist at the University of California, Davis studies animal communication and sexual selection, with a focus on understanding the amazing diversity and complexity in animal signals. Check out the story in this Science Nation video. Credit: Science Nation, NSF
Research conducted by biologists at the University of Maryland, College Park shows that when two neighboring termite families meet within the same log, one or both families' kings and queens are killed and a new, merged, cooperative colony results. Check out the story in this audio slideshow and news release.
Credit: Zina Deretsky, National Science Foundation
According to a study by scientists at the University of Arizona, female house finches are able to change their hormonal makeup to ensure male birds hatch later, grow faster and spend less time in the nest than their sisters. Read more in this news release.
Credit: Alex Badyaev
The Integrative Organismal Systems Division (IOS) in NSF's Directorate for Biological Sciences supports research aimed at an integrative understanding of organisms. The goal is to predict why organisms are structured the way they are and function as they do. The division particularly encourages research projects that innovatively apply systems biology approaches and that lead to new conceptual and theoretical insights and predictions about integrated organismal properties that may be experimentally verified.
Scientists studying the relationship between testosterone and natural selection in an American songbird, the dark-eyed junco, reported that extreme testosterone production puts male dark-eyed juncos at a disadvantage.
A University of California, San Diego study shows that increased environmental variation causes birds to lay more eggs at a time. In addition, increased predation pressure experienced by open-nesting birds causes them to lay smaller clutches than cavity-nesting birds, literally having fewer eggs in one basket to spread the risk.
August 23, 2010
Make Way for Ducklings
What wood ducks are revealing about threats to our fine feathered friends
Parent birds know best when it comes to taking care of their babies. But, when food gets scarce and they are forced to fly longer distances to grab a bite, "egg sitting" time drops off. What impact does this have on their brood?
"I guess everybody, from a human health perspective, knows that what a mother does during pregnancy can have all sorts of effects on her babies," says Bill Hopkins, an associate professor in the Department of Fisheries and Wildlife Sciences at Virginia Tech. He is holding a duckling in his hand. It's one of many he and his team are studying. "We study how these little guys can be affected by the things that mom does."
A member of his research team, Sarah DuRant, examines an egg. "If you look really closely," she says, "you can see the embryo moving."
With the support of the National Science Foundation (NSF), ecologists Hopkins and DuRant are studying wood ducks to better understand the impact of mom's nesting behavior on her ducklings and their ability to survive.
"How much time a female spends on her nest is going to influence the temperature that the nest is at," notes DuRant. The researchers incubate eggs at different temperatures to simulate warmer and cooler nesting conditions. "What we're interested in are very, very subtle changes in temperature, maybe a degree Celsius at most," adds Hopkins.
DuRant says they already see differences in the developing embryo. "Our embryos in the lowest temperature are going to develop a little bit slower than embryos in our higher temperatures," she says.
And once the ducklings are hatched, researchers are finding that just a slightly cooler nest can dramatically alter the health and vitality of an individual.
"They may look healthy, but if you actually dig a little deeper, we see a number of physiological deficits. Their immune systems aren't developing as rapidly. They appear to be almost developmentally stunted," explains Hopkins. "We see that they have changes in terms of endocrine function; in terms of stress hormones. We see changes in thermoregulatory capacity and locomotor performance. They swim slower than the same individuals from the same clutch. Swimming is a critical part of their early survival. They've got to avoid predators."
This research is not just about wood ducks. It has implications for many birds living in conditions where their nesting behaviors and habitats are disrupted.
"If their immune system isn't functioning as well as it needs to be and disease wipes through, then those guys aren't going to make it," says DuRant. "For many species that are breeding earlier in the year, those young are going to be exposed to colder temperatures so if they can't regulate their body temperature, then they're also going to die."
Hopkins hopes these findings will improve future conservation strategies.
"If you have an area, say, that's subjected to ecotourism, where you may have a lot of disturbance around nesting areas, those sorts of areas may actually come at a cost," he says.
That could adversely affect the health and vigor of future generations. Hopkins and his team want to learn all they can about what it will take to keep these little guys thriving--and following in mom's footsteps.