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Behavior and Ethology Commons

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2008

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Articles 1 - 30 of 87

Full-Text Articles in Behavior and Ethology

Unintended Facilitation Between Marine Consumers Generates Enhanced Mortality For Their Shared Prey, F. Joel Fodrie, Matthew D. Kenworthy, Sean P. Powers Dec 2008

Unintended Facilitation Between Marine Consumers Generates Enhanced Mortality For Their Shared Prey, F. Joel Fodrie, Matthew D. Kenworthy, Sean P. Powers

University Faculty and Staff Publications

We manipulated predator densities and prey vulnerability to explore how interactions between two predators affect overall mortality of their shared prey. Our threemember study system included eastern oysters (Crassostrea virginica) and two of its major consumers: southern oyster drills (Stramonita haemastoma) and stone crabs (Menippe adina). Field experiments demonstrated that drills and crabs foraging together generated higher than expected oyster mortality based on each species operating independently, even though crabs also killed some drills. In subsequent laboratory trials, we experimentally mimicked the handling of oysters by foraging crabs and confirmed that crabs facilitated drills by breeching oyster valves, thereby granting …


Tb199: Ant–Homopteran Relationships: Relevance To An Ant Invasion In Maine, Katherine E. Mcphee, Eleanor Groden, Francis A. Drummond Oct 2008

Tb199: Ant–Homopteran Relationships: Relevance To An Ant Invasion In Maine, Katherine E. Mcphee, Eleanor Groden, Francis A. Drummond

Technical Bulletins

The richness and diversity of native ant species on Mt. Desert Island, Maine, have been reduced in areas infested with Myrica rubra (European red ant). In general, the success of invasive ant species has been attributed to interference and exploitative competition coupled with the ants’ opportunistic diets. In field experiments on Mount Desert Island, Maine, M. rubra discovered and recruited to baits faster than native ants. This study also showed that M. rubra displaced most native ant species from food resources (Garnas 2005). This, together with M. rubra’s aggressive defense of invaded territories, has led to fewer native ants in …


When To Be A Dear Enemy: Flexible Acoustic Relationships Of Neighbouring Skylarks, Alauda Arvensis, Elodie Briefer, Fanny Rybak, Thierry Aubin Oct 2008

When To Be A Dear Enemy: Flexible Acoustic Relationships Of Neighbouring Skylarks, Alauda Arvensis, Elodie Briefer, Fanny Rybak, Thierry Aubin

Ethology Collection

Numerous territorial species are less aggressive towards neighbours than strangers. This tolerance towards neighbouring conspecifics, termed the ‘dear enemy’ effect, seems to be a flexible feature of the relationship between neighbours, and has been shown to disappear in some species after experimental or natural modifications of the context. However, the maintenance over time of this singular relationship has been poorly studied. In this study, we followed the change of dear enemy relationships during the breeding season in a territorial songbird with a complex song, the skylark. We examined in the field the response of territory owners to playbacks of neighbour …


Diet Influences Mate Choice Selectivity In Adult Female Wolf Spiders, Eileen Hebets, Jennifer Wesson, Paul S. Shamble Aug 2008

Diet Influences Mate Choice Selectivity In Adult Female Wolf Spiders, Eileen Hebets, Jennifer Wesson, Paul S. Shamble

Eileen Hebets Publications

Most studies of female choice have assumed that mating preferences are shared within a population or species. However, variation both within and among females exists in natural populations, and foraging history is among the many ways in which females may vary. Here, we used diet manipulations in an effort to understand how foraging history influences female mate choice. Immature Schizocosa wolf spiders collected from a mixed population of brush-legged and non-ornamented males were reared in the laboratory on two diets that varied in both quality and quantity (low/high diet). For low- and high-diet individuals, we recorded data on rates of …


A Note On The Effectiveness Of Behavioural Rehabilitation For Reducing Inter-Dog Aggression In Shelter Dogs, Jane S. Orihel, David Fraser Aug 2008

A Note On The Effectiveness Of Behavioural Rehabilitation For Reducing Inter-Dog Aggression In Shelter Dogs, Jane S. Orihel, David Fraser

Interactive Behavior Collection

The effectiveness of a rehabilitation program for reducing inter-dog aggression was evaluated at the municipal animal shelter. Sixteen dogs (of 60 examined) met the study criteria of medium inter-dog aggression as determined by an inter-dog aggression test. These dogs received a 10-day treatment of daily rehabilitation for 30 min (rehabilitation group, n = 9) or daily release into an outdoor enclosure for 30 min (control group, n = 7). Rehabilitation consisted of desensitising and counter-conditioning dogs to the approach of other ‘‘stimulus’’ dogs. Most dogs in the rehabilitation group showed a decline in aggression scores when re-tested after the last …


Gender-Specific Differences In Spatial Behavior Of The Flesh Fly, Sarcophaga Crassipalpis., Caleb Joseph Paquette May 2008

Gender-Specific Differences In Spatial Behavior Of The Flesh Fly, Sarcophaga Crassipalpis., Caleb Joseph Paquette

Electronic Theses and Dissertations

Territoriality in the flesh fly, Sarcophaga crassipalpis (Diptera: Sarcophagidae) was studied in the laboratory. In rectangular enclosures, male flies exhibited a lower tolerance (occupation of the same physical space) of same-sex conspecifics than did female flies. In circular arenas, male flies showed significantly higher levels of spatial separation among themselves (as determined from nearest neighbor analyses) than did females: males were distributed uniformly whereas females were nearly random. The male spatial behavior occurred during the photophase but not the scotophase of light-dark cycles, suggesting that visual cues are required for maintenance of inter-individual spacing. No significant differences in male spacing …


The Spatial Memory Of African Elephants (Loxodonta Africana): Durability, Interference, And Response Biases, Robert H.I. Dale May 2008

The Spatial Memory Of African Elephants (Loxodonta Africana): Durability, Interference, And Response Biases, Robert H.I. Dale

Scholarship and Professional Work - LAS

Women and elephants never forget an injury.

-Saki (H. H. Munro), "Reginald on besetting sins," in Reginald (1904)

I am not sure whether the satirist H. H. Munro believed Saki's claim, although it may well be true (at least with regard to elephants). This chapter will examine some characteristics of elephant memory more systematically than did Saki.

In general, it is to an animal's advantage to remember some aspects (usually the stable features) of a situation for long periods and to remember other aspects (usually the unstable features) only temporarily. Consistent with recent arguments questioning the value of cognitive constructs …


Bat Community Dynamics And Foraging Activity Patterns In Young Regenerating Southern Pine Plantations And Mixed Hardwood Forests, Kathryn Marie Womack Apr 2008

Bat Community Dynamics And Foraging Activity Patterns In Young Regenerating Southern Pine Plantations And Mixed Hardwood Forests, Kathryn Marie Womack

Theses & Honors Papers

Forests of the southeastern U.S. are changing rapidly in species composition and extent of forest cover due to increasing conversion to pine (Pinus sp.) plantations , intensifying management practices, and expanding urbanization and sprawl. Questions related to the impacts of these changes on wild life species are of great conservation interest and management relevance. Highly mobile species with large home ranges and complex habitat requirements , such as bats, may be especially vulnerable to increasing human modification of landscapes. However, the impacts of such modifications on bat species are poorly understood . I sought to evaluate bat community structure and …


Development And Validation Of The Counterfactual Thinking For Negative Events Scale, Tarika Daftary Kapur, Mark S. Rye, Melissa B. Cahoon, Rahan S. Ali Apr 2008

Development And Validation Of The Counterfactual Thinking For Negative Events Scale, Tarika Daftary Kapur, Mark S. Rye, Melissa B. Cahoon, Rahan S. Ali

Department of Justice Studies Faculty Scholarship and Creative Works

We examined the psychometric properties of the newly created Counterfactual Thinking for Negative Events Scale (CTNES) in two studies involving university undergraduates. In Study 1 (N = 634), factor analysis revealed four subscales that correspond with various types of counterfactual thinking: Nonreferent Downward, Other-Referent Upward, Self-Referent Upward, and Nonreferent Upward. The subscales were largely orthogonal and had adequate internal consistency and test–retest reliability. The CTNES subscales were positively correlated with a traditional method of assessing counterfactual thinking and were related as expected to contextual aspects of the negative event, negative affect, and cognitive style. In Study 2 (N …


Effects Of Gregariousness, Conspicuousness, And Novelty On Blue Jay (Cyanocitta Cristata) Learned Avoidance And Stimulus Generalization Of Unpalatable Prey, Joyce M. Dykema Apr 2008

Effects Of Gregariousness, Conspicuousness, And Novelty On Blue Jay (Cyanocitta Cristata) Learned Avoidance And Stimulus Generalization Of Unpalatable Prey, Joyce M. Dykema

Avian Cognition Papers

I examined a variety of factors hypothesized to be important in the evolution and maintenance of aposematism. Aposematism occurs when prey individuals advertise their toxic or otherwise aversive nature to potential predators via evolved conspicuous signals. I conducted three experiments in which blue jays (Cyanocitta cristata) were allowed to search a printed grayscale pixilated background for grayscale pixilated moths in an open room. I manipulated moth appearance and food reward, and recorded jay predation on the varying moth stimuli. In my first experiment, I repeated Alatalo & Mappes’ (1996) study examining the effects of prey gregariousness, or grouping, …


Use Of A Geometric Rule Or Absolute Vectors: Landmark Use By Clark’S Nutcrackers (Nucifraga Columbiana), Debbie M. Kelly, Sarah Kippenbrock, Jennifer J. Templeton, Alan Kamil Mar 2008

Use Of A Geometric Rule Or Absolute Vectors: Landmark Use By Clark’S Nutcrackers (Nucifraga Columbiana), Debbie M. Kelly, Sarah Kippenbrock, Jennifer J. Templeton, Alan Kamil

Papers in Behavior in Biological Sciences

Clark’s nutcrackers (Nucifraga columbiana) were trained to search for a hidden goal located in the center of a four-landmark array. Upon completion of training, the nutcrackers were presented with tests that expanded the landmark array in the east-west direction, north-south direction and in both directions simultaneously. Although the birds learned to search accurately at the center of the landmark array during training, this search pattern did not transfer to the expansion tests. The nutcrackers searched at locations defined by absolute distance and/or direction relationships with landmarks in the training array. These results contrast with those from experiments with …


The Qualitative Assessment Of Responsiveness To Environmental Challenge In Horses And Ponies, Fabio Napolitano, Giuseppe De Rosa, Ada Braghieri, Fernando Grasso, Aldo Bordi, Françoise Wemelsfelder Feb 2008

The Qualitative Assessment Of Responsiveness To Environmental Challenge In Horses And Ponies, Fabio Napolitano, Giuseppe De Rosa, Ada Braghieri, Fernando Grasso, Aldo Bordi, Françoise Wemelsfelder

Sentience Collection

The responsiveness of 10 horses and 10 ponies to environmental challenge (represented by an open field test) was assessed using a qualitative approach based on free choice profiling methodology (FCP), which gives observers complete freedom to choose their own descriptive terms. Data were analysed with generalised Procrustes analysis (GPA), a multivariate statistical technique associated with FCP. A cross-validation of the outcomes of this approach to data recorded through quantitative behaviour analysis, and through a questionnaire given to the animals’ owner/riding instructor, was also performed using principal component analysis (PCA). Twelve undergraduate students generated their own descriptive vocabularies, by watching 20 …


Substrate-Dependent Signaling Success In The Wolf Spider, Schizocosa Retrorsa, Eileen Hebets, Damian O. Elias, Andrew C. Mason, Gary L. Miller, Gail E. Stratton Feb 2008

Substrate-Dependent Signaling Success In The Wolf Spider, Schizocosa Retrorsa, Eileen Hebets, Damian O. Elias, Andrew C. Mason, Gary L. Miller, Gail E. Stratton

Eileen Hebets Publications

Signals used in communication are often hypothesized to be optimally designed for their signaling environment. Here, we explore the importance of signaling substrate on seismic signal efficacy and reproductive behavior in the wolf spider, Schizocosa retrorsa: a species found on multiple signaling substrates (pine litter and/or red clay or sand). In this multimodal signaling species, simultaneous with conspicuous visual displays, males produce percussive seismic signals via an impulse mechanism which tends to excite a substrate evenly across a wide band of frequencies. We first quantified the transmission characteristics of this broadband percussive signal by playing recorded signals back across three …


Agonistic Signals Received By An Arthropod Filiform Hair Allude To The Prevalence Of Near-Field Sound Communication, Roger D. Santer, Eileen Hebets Jan 2008

Agonistic Signals Received By An Arthropod Filiform Hair Allude To The Prevalence Of Near-Field Sound Communication, Roger D. Santer, Eileen Hebets

Eileen Hebets Publications

Arthropod filiform hairs respond to air particle movements and are among the most sensitive animal sensory organs. In many species, they are tuned to detect predators or prey and trigger escape or prey capture behaviours. Here we show for the first time that these hairs also receive intraspecific near-field sound signals in an arachnid. During agonistic encounters, whip spiders (Arachnida, Amblypygi) perform antenniform leg vibration (ALV) displays that have significantly longer duration in contest winners than losers. During an ALV display: (i) the vibrating antenniform leg of the displaying whip spider is positioned close to the trichobothria (filiform hairs) on …


Supplementary Material: Agonistic Signals Received By An Arthropod Filiform Hair Allude To The Prevalence Of Near-Field Sound Communication, Roger D. Santer, Eileen Hebets Jan 2008

Supplementary Material: Agonistic Signals Received By An Arthropod Filiform Hair Allude To The Prevalence Of Near-Field Sound Communication, Roger D. Santer, Eileen Hebets

Eileen Hebets Publications

SUPPLEMENTARY METHODS
(i) Analysis of behaviour
(ii) Stimulator design

SUPPLEMENTARY RESULTS
(i) Typical contest behaviour
(ii) Additional data on ALV positioning relative to the receiver
(iii) Electrophysiological control experiments
(iv) Analysis of phase-locking

SUPPLEMENTARY REFERENCES

Includes 3 figures and 1 table.


Calf Development: Most Births At Night, Robert H.I. Dale Jan 2008

Calf Development: Most Births At Night, Robert H.I. Dale

Scholarship and Professional Work - LAS

For many years, field researchers studying both African (Loxodonta africana) and Asian (Elephas maximas) elephants have indicated that they have observed relatively few births in situ, suggesting that most elephant dams give birth at night. For example, according to Cynthia Moss, "Possibly the majority of births occur at night and perhaps those that do take place in the daytime happen in secluded places" (1988, p. 151). Others, for example, Clive Spinage, have referred to "the old beliefs that the cows retreated to 'calving grounds' or that birth took place at night." (Spinage, 1994, p. 90). Although …


Environmental Conditions Affect Sperm Competition Risk In Japanese Beetles (Coleoptera: Scarabaeidae), Paul V. Switzer, Carissa A. Schoenick, Patrick C. Enstrom Jan 2008

Environmental Conditions Affect Sperm Competition Risk In Japanese Beetles (Coleoptera: Scarabaeidae), Paul V. Switzer, Carissa A. Schoenick, Patrick C. Enstrom

Paul V. Switzer

Males of many species guard their mates to prevent rivals from usurping paternity of the potential offspring. Environmental conditions, such as temperature, may affect a male’s ability to guard a female effectively and consequently the amount of sperm competition that occurs. We tested whether temperature and light affected mating behavior in laboratory experiments on the Japanese beetle, Popillia japonica Newman, a species in which males guard females for minutes to many hours after mating. When tested in groups, under conditions of high temperature and high light, males guarded females for shorter periods of time and males and females both mated …


Use Of Palm Trees As A Sleeping Site By Hamadryas Baboons In Ethiopia, Amy Schreier, Larissa Swedell Jan 2008

Use Of Palm Trees As A Sleeping Site By Hamadryas Baboons In Ethiopia, Amy Schreier, Larissa Swedell

Publications and Research

Hamadryas baboons sleep on cliffs throughout their range, and this can be attributed to the safety cliffs provide against predators in the absence of tall trees. In this paper, we report the first documented occurrence of hamadryas baboons sleeping in doum palm trees rather than on cliffs. Data derive from a study of hamadryas baboons at the Filoha site in lowland Ethiopia. During all-day follows, data were collected on travel patterns, band activity, and location. Variation in the baboons’ home range was characterized using vegetation transects. We discovered that one band in this population, Band 3, occasionally slept in doum …


Population Status , Hunting Regulations , And Harvests Of The Rocky Mountain Population Of Greater Sandhill Cranes, 1981–2005, Kammie L. Kruse, David E. Sharp, James A. Dubovsky Jan 2008

Population Status , Hunting Regulations , And Harvests Of The Rocky Mountain Population Of Greater Sandhill Cranes, 1981–2005, Kammie L. Kruse, David E. Sharp, James A. Dubovsky

Proceedings of the North American Crane Workshop

The Rocky Mountain Population (RMP) of greater sandhill cranes (Grus canadensis tabida) was not hunted in the U.S. from 1916 until 1981, when Arizona initiated the first modern-day season. Hunting programs in the U.S. were subsequently expanded to 6 states for the RMP and have been guided by a cooperative flyway management plan, including a harvest strategy, which has been periodically updated and endorsed by the Central and Pacific Flyway Councils. From a management perspective, 3 population parameters have been identified to monitor the status and health of this population: harvest, recruitment, and population size. The number of …


Management Of Lands Along The Platte River Fromelmcreek To Lexington, Nebraska, As Crane Habitat, James J. Jenniges, Mark M. Peyton Jan 2008

Management Of Lands Along The Platte River Fromelmcreek To Lexington, Nebraska, As Crane Habitat, James J. Jenniges, Mark M. Peyton

Proceedings of the North American Crane Workshop

To meet Federal Energy Regulatory Commission (FERC) license requirements for the operation of 5 hydroelectric power plants on the North Platte and Platte Rivers in Nebraska, the Nebraska Public Power District (NPPD) and The Central Nebraska Public Power and Irrigation District (Central) together have become the second largest owners and managers of lands for the conservation of endangered species and migratory waterbirds along the central reach of the Platte River. We describe here the management activities on the properties, success of the management in achieving objectives, and the response of sandhill (Grus canadensis) and whooping cranes (G. …


New Hunter Education Strategies To Protect Whooping Cranes In Texas And Kansas, Lee Ann Johnson Linam, Helen M. Hands, Jay Roberson Jan 2008

New Hunter Education Strategies To Protect Whooping Cranes In Texas And Kansas, Lee Ann Johnson Linam, Helen M. Hands, Jay Roberson

Proceedings of the North American Crane Workshop

The decline of the whooping crane (Grus americana) has often been attributed primarily to loss of habitat and overharvest. Although hunting of whooping cranes is now prohibited, shootings sometimes occur. Recent incidences have prompted the Texas Parks and Wildlife Department (Texas) and the Kansas Department of Wildlife and Parks (Kansas) to develop new strategies that increase hunter recognition of legal game species and awareness of endangered species concerns. Both agencies have produced or updated publications for goose and sandhill crane (Grus canadensis) hunters. Texas has developed video news releases for the general public and a video/DVD …


The Cuban Sandhill Crane As Umbrella Species: Relationship With Plant Diversity In Threatene D White Sand Savannahs, Duniet Marrero Garcia, Jose A. Osorio, Xiomara Galvez Aguilera, Felipe Chavez-Ramirez Jan 2008

The Cuban Sandhill Crane As Umbrella Species: Relationship With Plant Diversity In Threatene D White Sand Savannahs, Duniet Marrero Garcia, Jose A. Osorio, Xiomara Galvez Aguilera, Felipe Chavez-Ramirez

Proceedings of the North American Crane Workshop

This project describes relationships between the Cuban sandhill crane (Grus canadensis nesiotes) distribution and habitat use and plant diversity in white sand savannahs, a threatened ecosystem in Cuba. Data are based on habitat use and selection of 10 radio-tagged sandhill cranes in the Los Indios Ecological reserve, Isle of Youth. We used Arcview and satellite imagery to map broad vegetation categories. Within the general Pine-Palm savannahs specific plant communities were characterized using species composition and dominant plant life forms. Habitat types most used by cranes for feeding and nesting were also those with highest plant species richness and …


Trends In Sandhill Crane Numbers In Eastern New Mexico, James B. Montgomery Jr. Jan 2008

Trends In Sandhill Crane Numbers In Eastern New Mexico, James B. Montgomery Jr.

Proceedings of the North American Crane Workshop

Following a 1980s decline in the number of cranes in the Bitter Lake National Wildlife Refuge area of the Pecos River Valley in eastern New Mexico, peak fall migration numbers increased from 5,640 in 1989-90 to 15,790 in 2003-04 and 13,650 in 2004-05. Concurrently, hectares of corn grown for silage to feed dairy cows increased from 1,781 in 1989 to 8,013 in 2003 and 7,325 in 2004. The population goals of the NM Department of Game and Fish are being met but a downturn in the dairy industry could result in a decline in crane numbers.


Do We Need Such Rare Birds?, Stephen A. Nesbitt Jan 2008

Do We Need Such Rare Birds?, Stephen A. Nesbitt

Proceedings of the North American Crane Workshop

Gruidae is one of the oldest bird families; the genus Grus dates back at least 9 million years. Though they may have been around a long time, it is unlikely that cranes were ever among the most abundant of birds. Several of the 15 crane species occur today in such low numbers that they are considered in danger of becoming extinct. It has been posited that at the time of European colonization of North America whooping cranes may have numbered 10,000 individuals, so whooping cranes have likely always been rare birds. Rare has often been used as a synonym for …


Timing Of Molt In Florida Sandhill Cranes, Stephen A. Nesbitt, Stephen T. Schwikert Jan 2008

Timing Of Molt In Florida Sandhill Cranes, Stephen A. Nesbitt, Stephen T. Schwikert

Proceedings of the North American Crane Workshop

We observed feather molt in Florida sandhill cranes (Grus canadensis pratensis) between 1978 and 1997. We report data from 4 feather groups: remiges, rectrices, wing coverts and contour feathers. In all feather groups, the median date of ecdysis preceded endysis by about 30 days. Endysis in adults was generally later than it was in first- or second-year subadults. Remiges grew at a rate of 4.72 ± 1.56 SD mm per day. We estimated that primary and secondary wing feathers were usually regenerated within 45 to 70 days.


Safety Of West Nile Virus Vaccines In Sandhill Crane Chicks, Glenn H. Olsen, Kimberli J. Miller, Douglas E. Docherty, Valerie Bochsler Jan 2008

Safety Of West Nile Virus Vaccines In Sandhill Crane Chicks, Glenn H. Olsen, Kimberli J. Miller, Douglas E. Docherty, Valerie Bochsler

Proceedings of the North American Crane Workshop

West Nile virus arrived in North America in 1999 and has spread across the continent in the ensuing years. The virus has proven deadly to a variety of native avian species including sandhill cranes (Grus canadensis). In order to provide safe and efficacious protection for captive and released populations of whooping cranes (G. americana), we have conducted a series of four research projects. The last of these was a study of the effects of two different West Nile virus vaccines on young Florida sandhill crane (G. c. pratensis) chicks and subsequent challenge with the virus. …


Common Crane Management In Germany -Monitoring, Protection, And Scientific Work, Hartwig Prange Jan 2008

Common Crane Management In Germany -Monitoring, Protection, And Scientific Work, Hartwig Prange

Proceedings of the North American Crane Workshop

About 200,000 common cranes (Grus grus) from northern, middle, and northeastern parts of Europe are migrating on the West-European route. In the northeast part of Germany 160,000 cranes stop over simultaneously during migration. This number has increased since the early 1980´s by 3-fold. About 60 sites with from 200 to 50,000 cranes are systematically observed from August to December by local expert groups. The overnight roosts are in ponds, swamps, and lakes, actively flooded meadows, and brown coal mines as well as in shallow backwaters of the Baltic Sea. They have been used year after year. More than …


A Low Intensity Sampling Method For Assessing Blue Crab Abundance At Aransas National Wildlife Refuge And Preliminary Results On The Relationship Of Blue Crab Abundance To Whooping Crane Winter Mortality, Bruce H. Pugesek, Michael J. Baldwin, Thomas V. Stehn Jan 2008

A Low Intensity Sampling Method For Assessing Blue Crab Abundance At Aransas National Wildlife Refuge And Preliminary Results On The Relationship Of Blue Crab Abundance To Whooping Crane Winter Mortality, Bruce H. Pugesek, Michael J. Baldwin, Thomas V. Stehn

Proceedings of the North American Crane Workshop

We sampled blue crabs (Callinectes sapidus) in marshes on the Aransas National Wildlife Refuge, Texas from 1997 to 2005 to determine whether whooping crane (Grus americana) mortality was related to the availability of this food source. For four years, 1997 - 2001, we sampled monthly from the fall through the spring. From these data, we developed a reduced sampling effort method that adequately characterized crab abundance and reduced the potential for disturbance to the cranes. Four additional years of data were collected with the reduced sampling effort methods. Yearly variation in crab numbers was high, ranging …


Reproductive Health Of The Florida Flock Of Introduced Whooping Cranes, Marilyn G. Spalding, Martin J. Folk, Stephen A. Nesbitt Jan 2008

Reproductive Health Of The Florida Flock Of Introduced Whooping Cranes, Marilyn G. Spalding, Martin J. Folk, Stephen A. Nesbitt

Proceedings of the North American Crane Workshop

We examined the reproductive parameters of the introduced non-migratory flock of whooping cranes in Florida. Of 289 cranes introduced, 67 males and 65 females survived at least 3 years. The first behavioral pairs appeared in 1995, and eggs were first laid in 1999. In total, eggs were laid in 47 nests, 17 chicks hatched, and 4 young fledged by 2005. Severe drought conditions through 2001 were thought to be the reason for low reproductive nest success. In 2003 nesting conditions improved and 71% of nests with eggs, hatched chicks. During the next 2 years, with continued wet conditions, the proportion …


Aerial Census Techniques For Whooping Cranes On The Texas Coast, Thomas V. Stehn, Thomas E. Taylor Jan 2008

Aerial Census Techniques For Whooping Cranes On The Texas Coast, Thomas V. Stehn, Thomas E. Taylor

Proceedings of the North American Crane Workshop

The U.S. Fish and Wildlife Service, using aerial surveys, regularly monitors the whooping crane (Grus americana) population wintering along the Texas coast. These regular census flights began in 1950 and have produced a long-term data set on the growth of a small population of endangered birds. This paper describes the specific methodology used by the authors during census flights.