Terrestrial and Aquatic Ecology Commons^™

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 …

Feather Molt Of Nonmigratory Whooping Cranes In Florida, Martin J. Folk, Stephen A. Nesbitt, Jeannette M. Parker, Marilyn G. Spalding, Stephen B. Baynes, Kristen L. Candelora

Proceedings of the North American Crane Workshop

Molt patterns of wild whooping cranes (Grus americana) are largely unknown, and what knowledge we have has been based on scant data. We documented patterns of feather molt in nonmigratory whooping cranes in Florida during 1993-2005. All birds replaced flight feathers (remiges) in a synchronous (simultaneous) manner and spent time flightless. It took 38-46 days (mean = 44 days, n = 8) for feathers to regrow and birds to regain flight ability. When flightless due to remigial molt, cranes became more secretive and spent more time in wetlands during feather regrowth. Most (70%) whooping cranes first molted their …

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.

Body Mass Index (Bmi) Of Normal Sandhill Cranes, Stephen A. Nesbitt, Marilyn G. Spalding, Kristen L. Candelora, Paul S. Kubilis, Stephen T. Schwikert

Proceedings of the North American Crane Workshop

We used linear and mass measurements to construct a body mass index (BMI) for 2 subspecies of sandhill cranes (Grus canadensis). We found that BMI declined during the spring and early summer period. We used the BMI to show that juvenile Florida sandhill cranes (G. c. pratensis) reach their full mass at about 270 days of age, near the age at which they begin to leave the company of their parents. We used mensural data to predict a minimum expected mass for normal sandhill cranes which could be then used to evaluate the relative health of …

Use Of Clap Traps In Capturing Nonmigratory Whooping Cranes In Florida, Jeannette M. Parker, Martin J. Folk, Stephen B. Baynes, Kristen L. Candelora

Proceedings of the North American Crane Workshop

Between March 2001 and April 2005 we captured 28 nonmigratory Florida whooping cranes (Grus americana) with clap traps. Out of the 6 different capture methods we employed, the clap trap accounted for 42% of our birds captured. Its ability to safely capture one crane or multiple cranes simultaneously, flexibility in size and placement, and low cost make it an important tool to facilitate transmitter replacements and health checks among the experimental Florida whooping crane population.

Age, Sex, And Aggression In Florida Sandhill Cranes, Stephen A. Nesbitt

Proceedings of the North American Crane Workshop

Individually directed aggressive interactions were recorded for sandhill cranes in Florida over a 9-year period. Charges and stabs were the most frequently observed aggressive behaviors. Paired adults initiated most of the encounters. Males directed 67% of aggressive interactions toward other males and 84% of female aggressive interactions were directed toward other females. The sex of initiator was significantly correlated with the sex of the receiver (P = 0.001). Paired adults directed most aggression (64.7%) toward other paired adults. Aggression initiated by subadult cranes was directed toward adults and subadults with equal frequency. The aggressiveness in males as an indicator of …

First Cohort Of Migratory Whooping Cranes Reintroduced To Eastern North America: The First Year After Release, Richard P. Urbanek, Lara E. A. Fondow, Colleen D. Satyshur, Anne E. Lacy, Sara E. Zimorski, Marianne Wellington

Proceedings of the North American Crane Workshop

We describe the post-release movements and survival of the first cohort in the eastern migratory whooping crane (Grus americana) reintroduction from release the first winter through return the second winter. Six cranes were led behind ultralight aircraft from Necedah National Wildlife Refuge (NWR), Central Wisconsin, to Chassahowitzka NWR, Gulf Coast of Florida. After release in Florida, 1 of these cranes and another transported there by truck were killed by bobcats (Lynx rufus). The winter management protocol was modified and no further predation occurred. The 5 remaining cranes migrated unassisted back to Necedah NWR in spring, left …

Breeding Biology Of Re-Introduced Non-Migratory Whooping Cranes In Florida, Martin J. Folk, Stephen A. Nesbitt, Stephen T. Schwikert, James A. Schmidt, Kathleen A. Sullivan, Thomas J. Miller, Stephen B. Baynes, Jeannette M. Parker

Proceedings of the North American Crane Workshop

In the face of record-setting drought, the re-introduced flock of non-migratory whooping cranes in Florida has shown slow but steady progress toward achieving the first natural recruitment to the flock. Fourteen nests were initiated between 1999 and 2002. Two clutches have hatched a total of 4 chicks and 1 chick was raised to fledging. Captive-raised, soft-released whooping cranes have shown that they are capable of forming pair bonds, defending territories, building nests, laying fertile eggs, and hatching and rearing young. The key to the success of the project will be to have enough pairs producing enough young to offset annual …

Response Of Florida Sandhill Cranes To Nest Inspection, Stephen A. Nesbitt, Paul S. Kubilis, Stephen T. Schwikert

Proceedings of the North American Crane Workshop

We observed the response of nesting Florida sandhill cranes (Grus canadensis pratensis) to 27 instances of nest inspection. The disturbed bird flew from the area 81% and walked 19% of the time. The median distance moved was 330 meters (range 28 to 480 meters). The median length of time the nest was left unattended following inspection was 50 min (range: 10 to 166 min). The median length of time that observers stayed at the nest was 16 min (range: 5 to 48 min). Ten of the nests inspected (40%) eventually failed to produce young. Statistical analysis was focused …

Techniques Employed To Capture Whooping Cranes In Central Florida, Martin J. Folk, Stephen A. Nesbitt, Stephen T. Schwikert, James A. Schmidt, Kathleen A. Sullivan, Thomas J. Miller, Stephen B. Baynes, Jeannette M. Parker

Proceedings of the North American Crane Workshop

During the course of re-introduction of a non-migratory flock of whooping cranes to Florida (1993-2002) a variety of techniques were used to capture 105 free-living birds. The most commonly used technique was hand-capture from a feed trough blind (45 birds). Whooping cranes were also captured by use of snares, several types of nets, and by hand. All techniques were relatively safe and posed little risk to the birds, a primary concern when dealing with rare birds. We found it useful to employ a diversity of techniques because some methods work better than others under differing circumstances. Capturing whooping cranes for …

Morbidity And Mortality Factors In Pre-Fledged Florida Sandhill Crane (Grus Canadensis Pratensis) Chicks, Robert J. Dusek, Marilyn G. Spalding, Donald J. Forrester, Nicholas Komar, Jonathan F. Day

Proceedings of the North American Crane Workshop

One hundred and fifteen Florida sandhill crane (Grus canadensis pratensis) chicks were captured in Osceola and Lake Counties, Florida in 1998 - 2000 and examined for evidence of disease. Evidence of Eimeria gruis and/or E. reichenowi infection was found in 52% of chicks examined. Ten chicks were positive for antibodies to St. Louis encephalitis virus and 1 of these chicks was also positive for antibodies to eastern equine encephalitis virus. Predation was the most commonly identified cause of mortality. An unidentified microfilaria, and an unknown protozoan were detected in blood smears from crane chicks. A number of other …

Injuries And Abnormalities Of Sandhill Cranes Captured In Florida, Stephen A. Nesbitt, Marilyn G. Spalding, Stephen T. Schwikert

Proceedings of the North American Crane Workshop

Observations of gross pathological abnormalities were made during handling of sandhill cranes (Grus canadensis) captured for banding in Florida. One hundred fifty-six of 1,331 (11.7%) cranes examined showed evidence of one or more anomalies that were the result of disease, congenital deformity, or injury. Most frequent were abnormalities of the legs and feet, followed by abnormalities of the bill. Injuries of the eyes, head, and neck were also noted. Many of these birds were observed subsequent to banding and survived for several years with their injuries, though some never succeeded in reproducing.

Fine Root Vitality And Its Application In A Minirhizotron Study Of A Co2 Enrichment In A Florida Scrub Oak Ecosystem, Brandon Todd Herbert

Biological Sciences Theses & Dissertations

Minirhizotron images are assigned color codes to approximate the age of individual roots in situ. Triphenyl-tetrazolium chloride (TTC) has been used to measure the vitality of plant tissue by detecting dehydrogenase activity. TTC was used to assess the vitality of root tissue by color in a scrub oak ecosystem at Kennedy Space Center in central Florida. Roots were excavated, sorted into four color classes and stained with TTC. The product of the reduction of TTC by dehydrogenase enzyme, formazan, was extracted and its absorbance recorded using a spectrophotometer. A significant difference (p2 enrichment being conducted on a scrub oak …

The Use Of Radio Transmitters To Monitor Survival Of Sandhill Crane Chicks, Marilyn G. Spalding, Stephen A. Nesbitt, Stephen T. Schwikert, Robert J. Dusek

Proceedings of the North American Crane Workshop

To determine cause of death of Florida sandhill crane (Grus canadensis pratensis) chicks, in 1996-99 we glued shorttenn transmitters on newly hatched chicks. At about 10 days of age, these were replaced with surgically implanted subcutaneous transmitters in the field. Chicks were then recaptured at 55 to 65 days of age for more pennanent transmitters. This combination of transmitter configurations allowed us to track individuals through their rapid-growth period.

Ingested Metal In Whooping Cranes: An Endoscopic Technique For Removal And Implications For The Release Program, Glenn H. Olsen, Michael Wise

Proceedings of the North American Crane Workshop

Since 1993 when the whooping crane (Grus americana) release program in Florida started, 21 whooping cranes at the USGS Patuxent Wildlife Research Center (patuxent) have been diagnosed with gastrointestinal foreign bodies (primarily metal objects). A technique for safely removing these objects has been developed. The technique uses a flexible gastric endoscope to enter the proventriculus or ventriculus, and a snare or forceps passed down a channel of the endoscope to retrieve the foreign bodies. The technique is very successful, with the whooping crane usually back to its pen the next day. The longterm survival of the whooping cranes …

Water Conditioning And Whooping Crane Survival After Release In Florida, George F. Gee, Jane M. Nicolich, Stephen A. Nesbitt, Jeff S. Hatfield, David H. Ellis, Glenn H. Olsen

Proceedings of the North American Crane Workshop

About 50% of the whooping cranes (Grus americana) released in Florida die within the first year of release. Most of these deaths and those in subsequent years result from bobcat (Lynx rufus) predation. Choosing release sites in open marshes away from bobcat habitat has improved survival. We hypothesized that exposure to ponds (water conditioning) at the rearing site would encourage birds to roost in deeper water marshes after release and such exposure would thereby reduce bobcat predation. In this study, we moved young birds (ca 50 days of age) to netted pens with large (I5-m diameter), deep (30--60 …

Translocation Of Florida Sandhill Cranes To Georgia, Wesley A. Abler, Stephen A. Nesbitt

Proceedings of the North American Crane Workshop

Wild Florida sandhill cranes (Grus canadensis pratensis) were captured in Florida during 3 years and translocated to Grand Bay Wildlife Management Area (GBWMA), Georgia, in an attempt to establish a resident population of Florida sandhill cranes in a location with suitable habitat but no known population of resident sandhill cranes. Translocated second-year subadult cranes commingled with migratory greater sandhill cranes (G. c. tabida) yet remained on GBWMA each year after the migratory birds left the area. Twenty-one of 35 released cranes were visually identified at least 5 months after release, 3 cranes more than 15 months …

Aspects Of Reproduction And Pair Bonds In Florida Sandhill Cranes, Stephen A. Nesbitt, Martin J. Folk, Stephen T. Schwikert, James A. Schmidt

Proceedings of the North American Crane Workshop

From 1980-98 we captured and uniquely marked more than 400 Florida sandhill cranes (Grus canadensis prafensis). Age ratios of the marked population, excluding juveniles, was 66% adult and 33% subadult, and the sex ratio was 49% male and 51% female. Average clutch size for 210 nests checked from 1983-97 was 1.78 ± 0.18 (SD) and frequency of l-egg clutches varied among years. Average post-fledging brood size from 1991 to 1997 was 1.27 ± 0.17 (SD), included a 3-chick brood. Average percent ofYOlmg from 2 study areas, 1991-97 was 11.9 ± 3.23 (SD). We observed renesting up to 3 …

Interactions Of Sandhill Cranes And Whooping Cranes With Foreign Objects In Florida, Martin J. Folk, Stephen A. Nesbitt, Marilyn G. Spalding

Proceedings of the North American Crane Workshop

During studies of Florida sandhill cranes (Grus canadensis pralensis), greater sandhill cranes (G. c. tabida), and whooping cranes (G. americana) in Florida, we documented cases where these birds were in contact with human-produced objects that resulted in injury or death. We describe >40 instances in which cranes collided with powerlines or fences, became entangled in string or fishing line, or ingested foreign objects. The effect of human-produced objects on crane populations, particularly small populations, may be significant.

An Experimental Release Of Whooping Cranes In Florida: The First Three Years, Stephen A. Nesbitt, Martin J. Folk, Marilyn G. Spalding, James A. Schmidt, Stephen T. Schwikert, Jane M. Nicolich, Marianne Wellington, James C. Lewis, Tom H. Logan

Proceedings of the North American Crane Workshop

Fifty-two juvenile whooping cranes (Grus americana) were soft-released in Florida from February 1993 to April 1995. The birds were released in groups ranging in size from 5 to 14 individuals. The first-year survival rate was 0.42 for all years combined. First-year rates for each year were 0.36 for 1993, 0.32 for 1994, and 0.47 for 1995. Most mortality (62%) occurred during the first 3 months following release. The survival rate of 0.81 the second year after release was similar to that of Florida sandhill cranes (G. canadensis pratensis) (0.87). Predation by bobcats (Lynx rufus) …

Landscape Scale Habitat Conservation Plans: The California Experience, Lindell L. Marsh

Biodiversity Protection: Implementation and Reform of the Endangered Species Act (Summer Conference, June 9-12)

24 pages.

Contains 3 pages of references.

The Influence Of Temperature Salinity And Postlarval Transport On The Distribution Of Juvenile Spiny Lobsters, Panulirus Argus, In Florida Bay, Jennifer Marie Field

Biological Sciences Theses & Dissertations

Florida Bay is a major nursery for the Caribbean spiny lobster, Panulirus argus. The Bay contains a series of hardbottom or seagrass-covered basins separated by mudbanks, which serve as barriers to water circulation and presumably to transport of postlarvae. Temperatures can fluctuate dramatically in the basins and salinities range from 35 ppt to > 50 ppt. In this study I: i) investigated the physiological tolerance of spiny lobster postlarvae to combinations of temperature and salinity representative of conditions in Florida Bay, and ii) examined how postlarval availability and habitat structure influence spiny lobster recruitment into basins. I measured juvenile lobster …

Habitat Use By Florida Sandhill Cranes On The Kissimmee Prairie In Central Florida, Mary Anne Bishop

Proceedings of the North American Crane Workshop

Radio-tagged Florida sandhill cranes (Grus canadensis pratensis) were monitored for habitat use during 1985 and 1986 on the Kissimmee Prairie in central Florida. For both breeding and nonbreeding cranes, 93 % of the daytime locations were in 3 habitat types: cropland and plowed pasture, improved pasture, and palustrine emergent wetlands. Improved pasture was the most frequently used daytime habitat for both social classes. Radio locations were divided among 4 time blocks (3 diurnal, 1 nocturnal) and 4 3-month seasons. Time-of-day effects for use of wetlands and improved pasture were only marginally significant (1' < 0.08 and l' < 0.09, respectively) for breeders and not significant (1' < 0.30 and l' < 0.43, respectively) for nonbreeders. There was no significant difference in habitat use by breeders among seasons. Chi-square analyses of diurnal locations indicated that 4 of the 6 breeding cranes monitored used palustrine emergent wetlands more than their availability. The selection for wetlands reflects not only the rich food sources available, but also their use as midday loafing and drinking sites and as a source of cover that the upland habitats do not offer.

Gender Prediction From Body Measurements Of Two Subspecies Of Sandhill Cranes, Stephen A. Nesbitt, Clinton T. Moore, Kathleen S. Williams

Proceedings of the North American Crane Workshop

Linear discriminant functions estimated from leg length, bill length and body weight measurements of known subspecies and known gender (KS-KG) Florida (FSH) and greater sandhill cranes (GSH) (Grus canadensis pratensis and G. c. tabida, respectively) were used to predict gender of known subspecies and unknown gender (KS-UG) individuals. Mean body measurements were larger among males than among females of either subspecies, but the difference in mean bill length between genders was larger among GSH than among FSH cranes. Gender misclassification was less frequent among GSH than among FSH cranes. Of birds whose measurements fell outside of the 80% …