169 research outputs found

    Do we need such rare birds?

    Get PDF
    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 endangered, however some organisms are rare by natural occurrence and not necessarily about to become extinct as the term rare and endangered would imply. It stands to reason, though, that those things that occur in low numbers are more liable to extinction than those in greater abundance. The amount of society’s resources that have been committed to preventing the decline or extinction of rare animals has been in the billions of dollars; with millions of acres of land and thousands of years of efforts being dedicated to this same purpose. But to what avail? Aren’t we still losing species at an alarming rate? Does the pace of their loss not seem to be accelerating? Accompanying the disappearance of species from the planet we often hear the cynical drone “why bother, they were doomed anyway, otherwise they would not have been rare in the first place.” Follow this course of logic to its end point and the product of the argument becomes appallingly apparent. Would we really be happy sharing the planet with nothing other than pigeons, cockroaches, house sparrows and rats? Let’s hope not! As humanity’s unkind progress overwhelmed those species that had the misfortune to be in the way, and before we excuse our insolent sins with so cavalier a notion as forgone doom, we should pause and fully appreciate what it is we are losing

    ASPECTS OF REPRODUCTION AND PAIR BONDS IN FLORIDA SANDHILL CRANES

    Get PDF
    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 times, even after chicks had been hatched and reared for up to 16 days. Re-pairing following death or divorce was documented and was particularly noteworthy in a female that oscillated between 2 males during 4 years of observation

    Reproductive Health of the Florida Flock of Introduced Whooping Cranes

    Get PDF
    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 of pairs that laid eggs increased, but only 17% of those nests hatched. Embryos could not be seen in most of the decomposed eggs that were examined. In an effort to determine the cause for the low reproductive success of the flock, we examined the effects of behavioral pair formation, mortality, gonad size and histology, age, egg laying, hatching success, egg size, fertility, and egg microbial culture results on nesting success. When compared with the natural wild Aransas/Wood Buffalo flock, the productivity of birds reaching 8 years (100% egg laying, hatching, 60% fledging) was very low. When compared with the originating captive flock, however, evidence of fertility was similar. Productivity did however, increase in the captive flock beyond 8 years of age. At the time of this report, the reproductive birds in the Florida resident flock remain relatively young when compared with the captive flock. Therefore there may be improvement of reproductive success as the Florida flock ages

    INTERACTIONS OF SANDHILL CRANES AND WHOOPING CRANES WITH FOREIGN OBJECTS IN FLORIDA

    Get PDF
    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 \u3e40 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 INDIVIDUALIZED MARKING SCHEME FOR SANDHILL CRANES AND ITS USE TO DETERMINE FALL MIGRATION INTERVAL

    Get PDF
    A color-band based marking scheme was used for individually marking sa ndhill cranes in Florida. The band-loss rate was 2.8% per year between 1977 and 1988. Band loss was greatest on bands placed below the ankle joint and occurred most frequently during years 2 to 5. Color-marked individuals monitored during fall migration averaged 6.2 days (r=5-13 days) between the Jasper-Pulaski Fish and Wildlife area in northwestern Indiana and winlering areas in northern Florida

    Evaluation of Mixed-Phase Microphysics Within Winter Storms using Field Data and In Situ Observations

    Get PDF
    It is hypothesized that microphysical predictions have greater uncertainties/errors when there are complex interactions that result from mixedphased processes like riming. Use Global Precipitation Measurement (GPM) Mission ground validation studies in Ontario, Canada to verify and improve parameterization

    AN EVALUATION OF THREE AREAS FOR POTENTIAL POPULATONS OF WHOOPING CRANES

    Get PDF
    Sandhill crane (Grus canadensis) populations were evaluated on the Seney NWR, Michigan, the Okefenokee Swamp, Georgia, and in southcentral Florida to evaluate their suitability to support introduced whooping cranes (G. americana). This paper compares data collected at these sites and additional data collected in northcentral Florida. The length of the egg-laying period varied from 4.5 months in central Florida to 1 month at Seney, but egg-laying ceased at all sites from mid-May to early June. Mean clutch sizes were similar 0.7-1.9). Renesting ranged from 79% in northcentral Florida to \u3c=5% at Seney. These dates and values are consistent with nesting successes that ranged from 48% in northcentral Florida to 80% at Seney. Average annual recruitment, 12.3 juveniles/lOa adults, was highest on the Kissimmee Prairie in southcentral Florida. Average annual horne range size for the non-migratory populations were 1 km2 on the Okefenokee and 6.6 km2 on the Kissimmee. Nesting season horne range sizes ranged from 0.5 km2 on the Okefenokee to 1.8 km2 at Seney. All candidate populations successfully satisfied most of the guidelines for potential whooping crane populations as established by the Whooping Crane Recovery Team. Once reintroduction techniques have been refined, any or all of the study sites have the capacity to accommodate a flock of whooping cranes commensurate with Whooping Crane Recovery Team recommendations

    Thoracic Operations for Pulmonary Nodules Are Frequently Not Futile in Patients with Benign Disease

    Get PDF
    IntroductionPulmonary nodules often require operative resection to obtain a diagnosis. However, 10 to 30% of operations result in a benign diagnosis. Our purpose was to determine whether negative thoracic operations are futile by describing the pathological diagnoses; determining new diagnoses and treatment changes initiated based on operative findings; and assessing morbidity, mortality, and cost of the procedure.MethodsAt our academic medical center, 278 thoracic operations were performed for known or suspected cancer between January 1, 2005, and April 1, 2009. We collected and summarized data pertaining to preoperative patient and nodule characteristics, pathologic diagnosis, postoperative treatment changes resulting from surgical resection, perioperative morbidity and mortality, and hospital charges for patients with benign pathology.ResultsTwenty-three percent (65/278) of patients who underwent surgical resection for a suspicious nodule had benign pathology. We report granulomatous disease in 57%, benign tumors in 15%, fibrosis in 12%, and autoimmune and vascular diseases in 9%. Definitive diagnosis or treatment changes occurred in 85% of cases. Surgical intervention led to a new diagnosis in 69%, treatment course changes in 68% of benign cases, medication changes in 38%, new consultation in 31%, definitive treatment in 9%, and underlying disease management in 34%. There was no intraoperative, in-hospital, or 30-day mortality. Postoperative in-hospital events occurred in seven patients. The mean total cost was 25,515withameancostperdayof25,515 with a mean cost per day of 7618.ConclusionsPatients with a benign diagnosis after surgical resection for a pulmonary nodule received a new diagnosis or had a treatment course change in 85% of the cases
    • …
    corecore