Behavior and Ethology Commons^™

Nonlinear Effects Of Group Size On The Success Of Wolves Hunting Elk, Daniel R. Macnulty, Douglas W. Smith, L. David Mech, John A. Vucetich, Craig Packer

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Despite the popular view that social predators live in groups because group hunting facilitates prey capture, the apparent tendency for hunting success to peak at small group sizes suggests that the formation of large groups is unrelated to prey capture. Few empirical studies, however, have tested for nonlinear relationships between hunting success and group size, and none have demonstrated why success trails off after peaking. Here, we use a unique dataset of observations of individually known wolves (Canis lupus) hunting elk (Cervus elaphus) in Yellowstone National Park to show that the relationship between success and group …

Eavesdropping Parasitoids Do Not Cause The Evolution Of Less Conspicuous Signaling Behavior In A Field Cricket, Oliver M. Beckers, William E. Wagner

School of Biological Sciences: Faculty Publications

Males of many species produce conspicuous mating signals to attract females, but these signals can also attract eavesdropping predators and parasites. Males are thus expected to evolve signaling behaviors that balance the sexual selection benefits and the natural selection costs. In the variable field cricket, Gryllus lineaticeps, males sing to attract females, but these songs also attract the lethal parasitoid fly Ormia ochracea. The flies use male crickets as hosts for their larvae, primarily search for hosts during a 2 h period following sunset and prefer the same song types as female crickets. We tested whether males from high-risk populations …

Ramphotyphlops Braminus (Brahminy Blindsnake): Predation, Louis A. Somma

Papers in Herpetology

Ramphotyphlops braminus currently has the most widespread, near worldwide, nonindigenous distribution of any snake. In Florida, USA, R. braminus is rapidly expanding its distribution.

The stomach contents of a necropsied Dasypus novemcinctus (nine-banded armadillo) found on the premises of the Florida Department of Agriculture and Consumer Services in Gaisesville in March 2011 included an intact adult R. braminus. Dasypus novemcinctus is nonindigenous in Florida. It has a primarily insectivorous diet but occasionally preys upon small vertebrates, including reptiles. This is the first record of R. braminus in the diet of D. novemcinctus.

Do Clark’S Nutcrackers Demonstrate What-Where-When Memory On A Cache-Recovery Task?, Kristy L. Gould, Amy J. Ort, Alan C. Kamil

Avian Cognition Papers

What-where-when (WWW) memory during cache recovery was investigated in six Clark’s nutcrackers. During caching, both red- and blue-colored pine seeds were cached by the birds in holes filled with sand. Either a short (3 day) retention interval (RI) or a long (9 day) RI was followed by a recovery session during which caches were replaced with either a single seed or wooden bead depending upon the color of the cache and length of the retention interval. Knowledge of what was in the cache (seed or bead), where it was located, and when the cache had been made (3 or 9 …

Use Of Real-Time Pcr To Detect Canine Parvovirus In Feces Of Free-Ranging Wolves, L. David Mech, Emily S. Almberg, Douglas Smith, Sagar Goyal, Randall S. Singer

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Using real-time PCR, we tested 15 wolf (Canis lupus) feces from the Superior National Forest (SNF), Minnesota, USA, and 191 from Yellowstone National Park (YNP), USA, collected during summer and 13 during winter for canine parvovirus (CPV)-2 DNA. We also tested 20 dog feces for CPV-2 DNA. The PCR assay was 100%sensitive and specific with a minimum detection threshold of 104 50% tissue culture infective dose. Virus was detected in two winter specimens but none of the summer specimens. We suggest applying the technique more broadly especially with winter feces.

Four Events Of Host Switching In Aspidoderidae (Nematoda) Involve Convergent Lineages Of Mammals, F. Agustín Jiménez-Ruiz, Scott Lyell Gardner, Graciela Navone, Guillermo Ortí

Harold W. Manter Laboratory of Parasitology: Faculty Publications

The Great American Interchange resulted in the mixing of faunistic groups with different origins and evolutionary trajectories that underwent rapid diversification in North and South America. As a result, groups of animals of recent arrival converged into similar habits and formed ecological guilds with some of the endemics. We present a reconstruction of the evolutionary events in Aspidoderidae, a family of nematodes that infect mammals that are part of this interchange, i.e., dasypodids, opossums, and sigmodontine, geomyid, and hystricognath rodents. By treating hosts as discrete states of character and using parsimony and Bayesian inferences to optimize these traits into the …

Effect Of Diet Quantity And Quality On Female Sampling Behavior And Mating Preferences In A Field Cricket, Heidi L. Bulfer

School of Biological Sciences: Dissertations, Theses, and Student Research

Understanding the adaptive significance of variation in female mating behaviour is important because variation may often be favored by selection instead of a change in mean mating behaviour, particularly in variable environments. Females are known to adjust their mating behaviour to a variety of intrinsic and extrinsic factors including nutrition. There are multiple reasons why female behaviours might vary with nutrition; we tested two of these hypotheses: the search cost hypothesis and the direct benefits hypothesis. These hypotheses are not mutually exclusive, but they make contrasting predictions under some conditions. Low nutrition females may have less available energy to support …

Life History Tradeoffs And Phenotypic Plasticity: The Tale Of A Flight Polyphenic Field Cricket, Chandreyee Mitra

School of Biological Sciences: Dissertations, Theses, and Student Research

Most organisms are resource limited. Such limitations can result in tradeoffs between life history traits -- any traits that affect survival or reproduction. Flight polyphenic field crickets are thought to be a classic example of such a life history tradeoff, in which individuals tradeoff investment in flight capability and investment in reproduction. This polyphenism results from the interaction of two morphological traits: wing morphology (short or long) and flight muscle morphology (functional pink or non-functional white), and is affected by both genes and the environment. I examined life history traits of a flight polyphenic field cricket, Gryllus lineaticeps. First, …

Avian Influenza In Migratory Birds In The United States, 2007–2009, And Effects Of September Hunting Seasons On Survival, Harvest, And Recovery Rates Of Canada Geese Banded In Southeast Nebraska, Scott R. Groepper

School of Natural Resources: Dissertations, Theses, and Student Research

Highly-pathogenic avian influenza virus (HPAIV H5N1) poses risks to wild birds, poultry, and humans. Personnel with the United States Department of Agriculture-Animal Plant Health Inspection Service-Wildlife Services, state, and tribal wildlife agencies collected 168,940 samples from migratory birds from 2007 to 2009 to test for presence of HPAIV H5N1. No HPAIV was found, but other subtypes were discovered, including H5 and H7. I estimated prevalence of avian influenza virus by flyway and found prevalence was lowest each year in the Atlantic Flyway (6.7%–8.3%), highest in the Pacific Flyway in 2007 (13.3%) and 2008 (13.4%), and highest in the Mississippi Flyway …

The Effects Of Social Context And Cache Survival On Pinyon Jay Caching Behavior, Christine L. Keefe

School of Biological Sciences: Dissertations, Theses, and Student Research

I examined how pinyon jays (Gymnorhinus cyanocephalus) assess and determine the risk of pilferage to their caches. Jays were allowed to cache in an open room while alone or while being observed by a conspecific. In a counterbalanced design, jays cached in the opposite treatment once they had finished recovering their caches. I compared birds’ behaviors between treatments in order to determine whether jays consider the presence of an observer in measuring the local competitive environment. Once all jays had completed alone- and observed- treatments, I ran the experiment once more to determine if individuals were consistent in …

Exploring Sources Of Selection On The Multimodal Courtship Displays Of Two Sister Species Of Wolf Spiders: Schizocosa Crassipalpata And Schizocosa Bilineata, Mitch D. Bern

School of Biological Sciences: Dissertations, Theses, and Student Research

We examined multiple sources of selection on the multimodal courtship display of two sister species of wolf spiders, Schizocosa crassipalpata and Schizocosa bilineata. We first experimentally altered body condition in these two species by employing divergent diet treatments. We then tested for differences in adult male seismic courtship displays, visual courtship displays, and foreleg morphology; as well as adult female foreleg morphology. We then simultaneously examined both content and efficacy-based sources of selection on the visual and seismic multimodal courtship display of both species by conducting mate choice trials with high and low diet individuals across manipulated signaling environments …

The Complexities Of Wolf Spider Communication: Exploring Courtship Signal Function In Rabidosa Rabida, Dustin J. Wilgers

School of Biological Sciences: Dissertations, Theses, and Student Research

Evidence of signal complexity is seemingly pervasive across animal communication systems. Exploring signal function may provide insight into how these displays evolved and are maintained. This dissertation examines the courtship signal function in a grassland wolf spider. Rabidosa rabida lives in an extremely complex environment, and males use complex displays incorporating both visual and seismic modalities. Using several approaches I provide insight into the content and efficacy of the various signal components, as well as how variation in these displays influence female mating decisions in isolation and combined.

First, I manipulated male and female body condition using diet quantity manipulations …

Enigmatic Ornamentation Eases Male Reliance On Courtship Performance For Mating Success, Eileen Hebets, Jay A. Stafstrom, Rafael L. Rodriguez, Dustin J. Wilgers

Eileen Hebets Publications

Female preferences are frequently invoked to explain the widespread occurrence of elaborate male ornaments, yet empirical data demonstrating such preferences are sometimes equivocal or even contradictory. In the wolf spider Schizocosa stridulans, despite evidence of strong female choice, prior research has been unable to link the conspicuous sexually dimorphic foreleg ornamentation of males to their mating success. We conducted three experiments aimed at determining the function of this previously enigmatic ornamentation. Our first two experiments used males with phenotypically modified foreleg phenotypes in simple and complex mating environments in order to examine the relationship between the presence/absence of ornamentation …

Draft Genome Of The Red Harvester Ant Pogonomyrmex Barbatus, Chris R. Smith, Christopher D. Smith, Hugh M. Robertson, Martin Helmkampf, Aleksey Zimin, Mark Yandall, Carson Holt, Hao Hu, Ehab Abouheif, Richard Benton, Elizabeth Cash, Vincent Croset, Cameron R. Currie, Eran Elhaik, Christine G. Elsik, Marie-Julie Favé, Vilaiwan Fernandes, Joshua D. Gibson, Dan Graur, Wulfila Gronenberg, Kirk J. Grubbs, Darren E. Hagen, Ana Sofia Ibarraran Viniegra, Brian R. Johnson, Reed M. Johnson, Abderrahman Khila, Jay W. Kim, Kaitlyn A, Mathis, Monica C. Munoz-Torres, Marguerite C. Murphy, Julie A. Mustard, Rin Nakamura, Oliver Niehuis, Surabhi Nigam, Rick P. Overson, Jennifer E. Placek, Rajendhran Rajakumar, Justin T. Reese, Garret Suen, Shu Tao, Candice W. Torres, Neil D. Tsutsui, Lumi Viljakainen, Florian Wolschin, Jürgen Gadau

Department of Entomology: Faculty Publications

We report the draft genome sequence of the red harvester ant, Pogonomyrmex barbatus. The genome was sequenced using 454 pyrosequencing, and the current assembly and annotation were completed in less than 1 y. Analyses of conserved gene groups (more than 1,200 manually annotated genes to date) suggest a high-quality assembly and annotation comparable to recently sequenced insect genomes using Sanger sequencing. The red harvester ant is a model for studying reproductive division of labor, phenotypic plasticity, and sociogenomics. Although the genome of P. barbatus is similar to other sequenced hymenopterans (Apis mellifera and Nasonia vitripennis) in …

More Ornamented Males Exhibit Increased Predation Risk And Antipredatory Escapes, But Not Greater Mortality, Kasey D. Fowler-Finn, Eileen Hebets

Eileen Hebets Publications

Secondary sexual traits not only confer benefits to their bearer through increased mate acquisition, but may also have inherent costs, including the attraction of predators. Here, we examined the relationship between conspicuous secondary sexual traits and predation costs using two male morphs of Schizocosa wolf spiders: brushlegged and non-ornamented. In the field, we ran two predation experiments using artificial enclosures to directly test mortality costs of predation on the two male morphs. Using a natural predator, a larger wolf spider in the genus Hogna, we found no difference in predation on brush-legged vs. non-ornamented males. However, predation was depends …

Infectious Diseases In Yellowstone’S Canid Community, Emily S. Almberg, Paul C. Cross, L. David Mech, Doug W. Smith, Jennifer W. Sheldon, Robert L. Crabtree

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Each summer Yellowstone Wolf Project staff visit den sites to monitor the success of wolf reproduction and pup rearing behavior. For the purposes of wolf monitoring, Yellowstone National Park (YNP) is divided into two study areas, the northern range and the interior, each distinguished by their ecological and physiographical differences. The 1,000 square kilometer northern range, characterized by lower elevations (1,500–2,200 m), serves as prime winter habitat for ungulates and supports a higher density of wolves than the interior (20–99 wolves/1,000 km² versus 2–11 wolves/1,000 km²). The interior of the park encompasses 7,991 square kilometers, is higher …

Current Status And Future Directions Of Research In Complex Signaling, Eileen Hebets

Eileen Hebets Publications

The term ‘complex signaling’ reflects a recent scientific focus on the multiple elements frequently incorporated into animal signals (reviewed in Candolin, 2003; Hebets and Papaj, 2005; Partan and Marler, 2005; Bro-Jorgensen, 2010). It embodies a new appreciation that signals used in communication are regularly composed of numerous components and that each component may individually vary in a number of ways. For example, signal components may vary in their time or mechanism of production, in the efficacy of their transmission, and/or in their mechanism of reception, among others. Employing the term ‘complex signaling’ reminds us of the need to maintain a …

Chemical Communication In A Multimodal Context, Eileen A. Hebets, Aaron S. Rundus

Eileen Hebets Publications

All animals are equipped with multiple sensory systems (e.g., visual, chemical, acoustic, tactile, electrical, thermal), and signals perceived via these sensory systems facilitate communication. Such communication often involves displays that incorporate more than one signal from more than one sensory modality, resulting in multimodal signaling. The number of empirical and theoretical studies addressing issues of multimodal signaling is ever-increasing and this chapter highlights why crustaceans, as a taxonomic group, are ideal for advancing such studies. Early classifications of multimodal signaling sought to categorize signal components as either redundant or nonredundant, while more recent classifications lay out specific hypotheses relating to …

Male Field Crickets Infested By Parasitoid Flies Express Phenotypes That May Benefit The Parasitoids, Oliver M. Beckers, William E. Wagner

School of Biological Sciences: Faculty Publications

Parasites can cause changes in the phenotypes of their hosts that may benefit the parasite, the host, or both. To understand the evolutionary dynamics of host–parasite interactions it is necessary to first examine the effect of parasitic infestation on the host phenotype and whether the host or parasite benefits from these changes. The fly Ormia ochracea parasitizes the variable field cricket, Gryllus lineaticeps, and it uses male song to locate hosts for its lethal larvae. Adult flies preferentially orient to male songs with faster and longer chirps. We tested the effect of larval infestation on two types of host traits. …

Females Are Choosier In The Dark: Environment-Dependent Reliance On Courtship Components And Its Impact On Fitness, Aaron S. Rundus, Laura Sullivan-Beckers, Dustin J. Wilgers, Eileen Hebets

Eileen Hebets Publications

A broad understanding of multimodal courtship function necessitates knowledge of the potential information content of signal components, the efficacy of signal components in eliciting the appropriate receiver response, and the fitness consequences of mating decisions based upon various signal components. We present data addressing each of these requirements for the multimodal-signaling wolf spider, Schizocosa floridana Bryant. Using diet manipulations, we first demonstrate that both visual and seismic courtship signals are condition-dependent. Next, using high- and low-quantity diet individuals in mate choice trials across manipulated signaling environments, we demonstrate that the seismic signal is crucial for mating success and further show …

A Sticky Situation: Solifugids (Arachnida, Solifugae) Use Adhesive Organs On Their Pedipalps For Prey Capture, Rodrigo H. Willemart, Roger D. Santer, Andrew J. Spence, Eileen Hebets

Eileen Hebets Publications

Solifugids (Arachnida, Solifugae) have unique evertable adhesive organs on the tips of their pedipalps, named ‘suctorial’ or ‘palpal’ organs. Previous studies have shown that these organs enable solifugids to climb smooth glass-like surfaces and have hypothesized that these structures facilitate prey capture. Here, we use high-speed videography to demonstrate that the suctorial organs of Eremochelis bilobatus are its primary means of capturing insect prey. We also present calculations of the adhesive pressure exerted by these suctorial organs during real prey capture events.

Gray Wolf (Canis Lupus) Movements And Behavior Around A Kill Site And Implications For Gps Collar Studies, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Global Positioning System (GPS) radio-collars are increasingly used to estimate Gray Wolf (Canis lupus) kill rates. In interpreting results from this technology, researchers make various assumptions about wolf behavior around kills, yet no detailed description of this behavior has been published. This article describes the behavior of six wolves in an area of constant daylight during 30 hours, from when the pack killed a Muskox (Ovibos moschatus) calf and yearling on Ellesmere Island, Nunavut, Canada, to when they abandoned the kill remains. Although this is only a single incident, it demonstrates one possible scenario of pack …

Mechanisms For Decisions About The Future, Jeffrey R. Stevens

Jeffrey Stevens Publications

Evolutionary and psychological perspectives on decision making remain largely separate endeavors. The bounded rationality approach integrates these two perspectives by focusing on simple, plausible mechanisms of decision making and the cognitive capacities needed to implement these mechanisms. Decisions about the future provide a class of decisions that lend themselves to a bounded rationality approach. Though many different mechanisms may exist for making decisions about the future, only a subset of these mechanisms actually require a representation of the future. The bounded rationality approach helps focus on the cognitive capacities and decision mechanisms that are necessary for a full understanding of …

Complex Courtship Displays Facilitate Male Reproductive Success And Plasticity In Signaling Across Variable Environments, Dustin Wilgers, Eileen Hebets

Eileen Hebets Publications

Effective signal transmission is essential for communication. In environments where signal transmission is highly variable, signalers may utilize complex signals, which incorporate multiple components and modalities, to maintain effective communication. Male Rabidosa rabida wolf spiders produce complex courtship signals, consisting of both visual and seismic components. We test the hypothesis that the complex signaling of R. rabida contributes to male reproductive success in variable signaling environments. We first examine the condition-dependence of foreleg ornamentation (a presumed visual signal) and seismic signal components and find that both may provide potentially redundant information on foraging history. Next, we assessed reproductive success across …

The Degree Of Response To Increased Predation Risk Corresponds To Male Secondary Sexual Traits, Kasey Fowler-Finn, Eileen Hebets

Eileen Hebets Publications

Secondary sexual traits are expected to reflect a balance between sexual selection and natural selection. We test the hypothesis that plasticity in sexual advertisement behaviors can influence this trade-off, allowing showier traits than expected for a given level of predation risk. Specifically, we tested whether the degree of behavioral plasticity exhibited in response to chemical cues of a co-occurring predatory wolf spider corresponds to courtship rate and the degree of ornamentation in male wolf spiders. Both ornamented (brush-legged) males and non-ornamented males decreased locomotion, decreased their likelihood to court, and increased their time to initiate courtship in response to predator …

Use Of Cranial Characters In Taxonomy Of The Minnesota Wolf (Canis Sp.), L. David Mech, Ronald M. Nowak, Sanford Weisberg

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Minnesota wolves (Canis sp.) sometimes are reported to have affinity to a small, narrow-skulled eastern form (Canis lupus lycaon Schreber, 1775) and sometimes to a larger, broader western form (Canis lupus nubilus Say, 1823). We found that pre-1950 Minnesota wolf skulls were similar in size to those of wolves from southeastern Ontario and smaller than those of western wolves. However, Minnesota wolf skulls during 1970–1976 showed a shift to the larger, western form. Although Minnesota skull measurements after 1976 were unavailable, rostral ratios from 1969 through 1999 were consistent with hybridization between the smaller eastern wolf and …

Wolves, Canis Lupus, Carry And Cache The Collars Of Radio-Collared White-Tailed Deer, Odocoileus Virginianus, They Killed, Michael E. Nelson, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Wolves (Canis lupus) in northeastern Minnesota cached six radio-collars (four in winter, two in spring-summer) of 202 radio-collared White-tailed Deer (Odocoileus virginianus) they killed or consumed from 1975 to 2010. A Wolf bedded on top of one collar cached in snow. We found one collar each at a Wolf den and Wolf rendezvous site, 2.5 km and 0.5 km respectively, from each deer’s previous locations.

Movements Of Wolves At The Northern Extreme Of The Species’ Range, Including During Four Months Of Darkness, L. David Mech, H. Dean Cluff

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Information about wolf (Canis lupus) movements anywhere near the northern extreme of the species’ range in the High Arctic (.75uN latitude) are lacking. There, wolves prey primarily on muskoxen (Ovibos moschatus) and must survive 4 months of 24 hr/day winter darkness and temperatures reaching 253 C. The extent to which wolves remain active and prey on muskoxen during the dark period are unknown, for the closest area where information is available about winter wolf movements is .2,250 km south. We studied a pack of $20 wolves on Ellesmere Island, Nunavut, Canada (80°N latitude) from July 2009 …

Parsing Demographic Effects Of Canine Parvovirus On A Minnesota Wolf Population, L. David Mech, Sagar M. Goyal

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

We examined 35 years of relationships among wolf (Canis lupus) pup survival, population change and canine parvovirus (CPV) seroprevalence in northeastern Minnesota to determine when CPV exerted its strongest effects. Using correlation analysis of data from five periods of 7-years each from 1973 through 2007, we learned that the strongest effect of CPV on pup survival (r = -0.73) and on wolf population change (r = -0.92) was during 1987 to 1993. After that, little effect was documented despite a mean CPV seroprevalence from 1994 of 2007 of 70.8% compared with 52.6% during 1987 to 1993. We …

Problems With Studying Wolf Predation On Small Prey In Summer Via Global Positioning System Collars, Vicente Palacios, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

We attempted to study predation on various-sized prey by a male and female wolf (Canis lupus) with global positioning system (GPS) collars programmed to acquire locations every 10 min in the Superior National Forest of Minnesota. During May to August 2007, we investigated 147 clusters of locations (31% of the total) and found evidence of predation on a white-tailed deer (Odocoileus virginianus) fawn and yearling, a beaver (Castor canadensis), ruffed grouse (Bonasa umbellus), and fisher (Martes pennanti) and scavenging on a road-killed deer and other carrion. However, we missed finding …