Ecological scientists assess the fundamentals of animal behavior

Mate selection, foraging and defense mechanisms explored at ESA’s Annual Meeting

In this time of global change, understanding the basics of animal behavior and environmental interactions is just as important as predicting and planning for widespread impacts. Ecological scientists will assess the fundamentals of animal behavior—such as plant toxin detection in bushbaby foraging—and current adaptations to global change—like defense mechanisms of native lizards to red imported fire ant attacks and the role of antioxidants and radiation in barn swallow reproduction—at the Ecological Society of America’s (ESA) 95th Annual Meeting in Pittsburgh from August 1-6, 2010. Below is a sampling of some of the research to be presented on animal behavior:

Plant toxin detection in bushbaby foraging

Foraging animals face many obstacles when obtaining food—not the least of which is avoiding predators and poisonous plants, or at least limiting the intake of toxins. Clare McArthur from the University of Sydney and colleagues filmed the fruit-eating omnivorous primate, the thick-tailed bushbaby, as it foraged at night in forests at the Lajuma Nature Reserve, South Africa.

The bushbabies chose between a food patch hidden in a tree that contained various low concentrations of the plant toxin cineole, and a non-toxic food patch located near fresh leopard scat—indicating the nearby presence of predators. According to research to be presented at ESA’s Annual Meeting, the bushbabies’ behavior indicated a foraging “tipping point.” That is, to the bushbabies, the danger of eating food with five percent cineole was equivalent to the perceived risk of leopards on the ground.

The contributed oral session “Bushbaby foraging ecology: walking the tightrope between predation risk and plant toxins” led by Clare McArthur, University of Sydney, will be held Thursday, August 5, 2010 at 3:40 pm.

Other sessions on foraging and feeding include:

The poster session “Does the snake-mimic morphology of tiger swallowtail larvae repel predators?” by Tracy S. Feldman, University of Wisconsin-Stevens Point; the contributed oral session “Innate color preferences, behavioral plasticity, and constraints on color learning in the monarch butterfly, Danaus plexippus (Nymphalidae)” led by Martha R. Weiss, Georgetown University; and the contributed oral session “Competitive effects of a dominant arboreal ant (Azteca instabilis) on ground foraging ant diversity and community structure in a coffee agroecosystem” led by Katherine K. Ennis, University of  Michigan.

Lizard defense from invasive fire ants

One of the many modern-day challenges presented to scientists is the impact of invasive species on natural habitats and native populations. In the southern U.S., for example, red imported fire ants spread rapidly, destroy crops and sting humans and animals alike. For native fence lizards, Sceloporus undulatus, the options are to adapt and co-exist with these ants or to run the risk of lethal consequences.

Tracy Langkilde from Pennsylvania State University found elevated levels of stress hormones, called glucocorticoids, in lizard populations inhabiting areas near large numbers of fire ants. In other words, lizards exposed to repeated attacks by fire ants had higher stress levels and a heightened awareness of fire ant threats. As Langkilde explains, “this suggests that, rather than being a cause for concern, elevated levels of physiological stress within invaded [lizard] populations may be playing an important role in driving [adaptations] to novel threats.”

The contributed oral session “Stress and invasion: factors influencing the escape behavior of native fence lizards in response to introduced fire ants” by Tracy Langkilde, Pennsylvania State University, will be held Monday, August 2, 2010 at 4:00 pm.

Other sessions on species interactions include:

The contributed oral session “Double deception: ant-mimicking spiders fool both visually and chemically-oriented predators” by Divya Uma, Georgetown University; the poster session “Innate anti-predator behavior in captive-reared Piping Plovers (Charadrius melodus)” led by Theresa Wei Ying Ong, University of Michigan; and the contributed oral session “The impact of burning on lion (Panthera leo) habitat choice in an African savanna” led by Stephanie L. Eby, Syracuse University.

Antioxidants defend barn swallow sperm from radiation

Exposure to free radicals can affect sperm morphology and behavior—in a setting such as Chernobyl, these effects could help determine the fate of an entire species’ existence. For example, studies of barn swallows, Hirundo rustica, from radioactively contaminated areas around Chernobyl have shown changes in sperm motility and the frequency of abnormal sperm related to radiation levels. Naturally, mutations that prevent sperm from effectively swimming could lead to population declines.

Andrea Bonisoli Alquati from the University of South Carolina and colleagues analyzed the effects of radiation, namely oxidative damage, in barn swallow populations inhabiting areas near Chernobyl. As the researchers will discuss at ESA’s Annual Meeting, the findings suggest “a possible radioprotective role for antioxidants in free-ranging animals exposed to the fallout from Chernobyl.”

The contributed oral session “Antioxidant defenses and sperm swimming behavior in barn swallows from Chernobyl,” led by Andrea Bonisoli Alquati, University of South Carolina, will be held Monday, August 2, 2010 at 2:10 pm.

Other sessions on mate selection and reproduction include:

The poster session “Staying in the red: mating preferences for novel coloration in zebrafish (Danio rerio)” by M. Aaron Owen, Purdue University; the contributed oral session “Balancing the demands of migration and the physiological transition to breeding in Neotropical songbirds: a dual role for testosterone?” led by Christopher M. Tonra, University of Maine; and the poster session “Effects of a glyphosate-based herbicide on mate location in the wolf spider Pardosa milvina” led by Samuel C. Evans, Miami University.

ESA’s 95th Annual Meeting will be held August 1-6, 2010 in Pittsburgh, Pennsylvania. The meeting will include more than 3,000 scientists, students and educators and will center on the theme “Global Warming: The legacy of our past, the challenge for our future.”

The meeting program is available online in searchable format at eco.confex.com/eco/2010/techprogram/. All abstracts are embargoed until 12:00 am EST the day of their presentation. Contact Katie Kline atgro.asenull@eitak (or during the Meeting at 412-325-6060) for details or to register as a member of the press.