Demography of the San Francisco Gartersnake in Coastal San Mateo County, California

2011 ◽  
Vol 2 (1) ◽  
pp. 41-48 ◽  
Author(s):  
Brian J. Halstead ◽  
Glenn D. Wylie ◽  
Melissa Amarello ◽  
Jeffrey J. Smith ◽  
Michelle E. Thompson ◽  
...  

Abstract The San Francisco gartersnake Thamnophis sirtalis tetrataenia has been federally listed as endangered since 1967, but little demographic information exists for this species. We examined the demography of a San Francisco gartersnake population on approximately 213 ha of California coastal prairie in San Mateo County, California, from 2007 to 2010. The best-supported mark–recapture model indicated annual variation in daily capture probabilities and annual survival rates. Abundance increased throughout the study period, with a mean total population from 2008 to 2010 of 443 (95% CI  =  313–646) individuals. Annual survival was slightly greater than that of most other gartersnakes, with an annual probability of survival of 0.78 (0.55–0.95) in 2008–2009 and 0.75 (0.49–0.93) in 2009–2010. Mean annual per capita recruitment rates were 0.73 (0.02–2.50) in 2008–2009 and 0.47 (0.02–1.42) in 2009–2010. From 2008 to 2010, the probability of an increase in abundance at this site was 0.873, with an estimated increase of 115 (−82 to 326) individuals. The estimated population growth rate in 2008–2009 was 1.52 (0.73–3.29) and in 2009–2010 was 1.21 (0.70–2.17). Although this population is probably stable or increasing in the short term, long-term studies of the status of the San Francisco gartersnake at other sites are required to estimate population trends and to elucidate mechanisms that promote the recovery of this charismatic member of our native herpetofauna.

2018 ◽  
Vol 76 (4) ◽  
pp. 1107-1121 ◽  
Author(s):  
Gérald Chaput ◽  
Jonathan Carr ◽  
Jason Daniels ◽  
Steve Tinker ◽  
Ian Jonsen ◽  
...  

Abstract The migration dynamics and inter-annual variation in early at-sea survival of Atlantic salmon (Salmo salar) smolts over 14 years of study are reported for four river populations located in the Gulf of St. Lawrence (Canada). Acoustically tagged smolts were monitored at three points along their migration from freshwater to the Labrador Sea, a migration extending more than 800 km at sea and a period of 2 months. A hierarchical state-space version of the Cormack–Jolly–Seber model was used to estimate apparent survival rates from incomplete acoustic detections at key points. There was a positive size-dependent probability of survival through the freshwater and estuary areas; the odds of survival of a 16 cm smolt were 1.5–1.7 times higher than for a 13.5 cm smolt, length at tagging. Length adjusted (centred to the mean fork length of smolts during the study of 14.6 cm) survivals through the estuary and nearshore waters were estimated to range between 67 and 90% for the two river populations migrating through Chaleur Bay in contrast to lower survival estimates of 28–82% for the two populations from the neighbouring Miramichi Bay. Across the 14 years of study, survival estimates varied without trend for the populations of Chaleur Bay, but declined for the populations migrating through Miramichi Bay. Survival through the Gulf of St. Lawrence was variable but generally high among years and rivers, ranging from 96% day−1 to 99% day−1. Long term, replicated studies at multiple sites using acoustically tagged smolts can provide empirical data to examine hypotheses of the location and timing of factors contributing to smolt and post-smolt mortality of salmon at sea.


2018 ◽  
Vol 45 (2) ◽  
pp. 155 ◽  
Author(s):  
Chifuyu Horikoshi ◽  
Phil F. Battley ◽  
Edward O. Minot

Context The risk of secondary poisoning to native fauna during pest control operations is an issue of global concern. In New Zealand, non-target impacts during sodium fluoroacetate (1080) operations are particularly contentious. 1080 is used extensively for pest control for conservation, bovine tuberculosis control, and in plantation forestry for seedling protection from herbivores. The endemic New Zealand falcon (Falco novaeseelandiae) breeds in Kaingaroa forest, an intensively managed pine plantation where regular 1080 poison operations are conducted; however, causes of mortality and risks of secondary poisoning by 1080 are not well documented. Aims We aimed to investigate mortality and survival of adult falcons with an emphasis on assessing the possible role of 1080 poisoning in annual mortality. Methods Using radio-telemetry and visual observations, we monitored 37 marked adult falcons before and after 1080 operations in 2013–14 (16 through carrot-bait and 21 through cereal-bait operations) and assessed mortality causes through post-mortem examinations. Using Program MARK, the annual survival rates for adults and independent juveniles were estimated from long-term banding data (2003–2014). Key results Survival of falcons was high through both cereal-bait (21/21) and carrot-bait (15/16) 1080 operations (overall 95% CI for survival = 84–100%). The exception was a radio-tagged male that died of unknown causes within a fortnight of an operation and tested negative for 1080 residues. Three falcons were depredated by introduced mammals. One falcon was found dead in an emaciated condition but evidently died from head injury through Australasian magpie (Cracticus tibicen) attack. The annual survival rate of falcons estimated from long-term banding was 80 ± 6.0% (mean ± s.e.) for adults and 29 ± 0.1% for juveniles. Conclusions No adult falcon death was attributable to 1080 poisoning in this study. Identifiable mortalities were attributable to depredation by introduced mammals and an injury from an Australasian magpie. The annual survival rate of Kaingaroa falcons was comparable to those of other raptor species worldwide. Implications The risk to adult falcons from 1080 secondary poisoning is likely low. Whether this is also true for juveniles requires further study.


2018 ◽  
Vol 9 (1) ◽  
pp. 168-179 ◽  
Author(s):  
Christopher A. Dobony ◽  
Joshua B. Johnson

Abstract White-nose syndrome (WNS) is a disease that has killed millions of bats in eastern North America and has steadily been spreading across the continent. Little brown myotis Myotis lucifugus populations have experienced extensive declines; however, some localized populations have remained resilient, with bats surviving multiple years past initial WNS exposure. These persistent populations may be critical to species recovery, and understanding mechanisms leading to this long-term survival and persistence may provide insight into overall bat and disease management. We monitored a maternity colony of little brown myotis on Fort Drum Military Installation in northern New York between 2006 and 2017 to determine basic demographic parameters and find evidence of what may be leading to resiliency and persistence at this site. Total colony size declined by approximately 88% from 2008 to 2010 due primarily to impacts of WNS. Counts of all adults returning to the colony stabilized during 2010–2014 (mean = 94, range 84–101) and increased after 2014 (mean = 132, range = 108–166). We captured 727 little brown myotis (575 females, 152 males) and banded 534 individuals (389 females, 145 males) at the colony. The majority of sampled bats showed evidence of recent past WNS infection and exposure to Pseudogymnoascus destructans, and we documented pervasive presence and limited viability of the fungus within the colony's main roosting structure. We recaptured 98 individually marked females in years after initial banding, and some individuals survived at least 6 y. Ninety-one percent of all adult females, 93% of recaptured bats, and 90% of 1-y-old females (i.e., bats recaptured the first year after initial capture as juveniles) showed evidence of reproduction during the monitoring period. Using mark–recapture models, we estimated annual survival rates of juvenile and adult little brown myotis during 2009–2016 and examined whether reproductive condition or evidence of recent infection of WNS had any effect on survival. Annual survival rates were similar between juveniles and adults, but highly variable, ranging from 41.0 to 86.5%. Models indicated that neither evidence of recent past exposure to WNS nor reproductive status were related to survival. No one parameter stood out as being responsible for this colony's continued existence, and it is likely that many interwoven factors were responsible for the observed resilience. Although relatively high reproductive effort from all females (i.e., both1-y-old and >1-y-old ) and intermittently suitable survival rates have led to the continued persistence of, and population increases in, this summer colony, mortality from WNS and inherently low reproductive potential still seemed to be limiting population growth. Until there is a better understanding of this overall potential resiliency in little brown myotis, we recommend considering minimizing disturbance and direct human involvement within these persisting populations to allow whatever natural recovery that may be occurring to evolve uninterrupted.


2020 ◽  
Author(s):  
Verónica Quirici ◽  
Esteban Botero-Delgadillo ◽  
Paulina González-Gómez ◽  
Pamela Espíndola-Hernández ◽  
Brayan Zambrano ◽  
...  

Abstract Background: Many studies have attempted to link variation in corticosterone (Cort), the primary glucocorticoid (GC) in birds, with reproductive output, however the consequences of variation in Cort levels on survival probability have been relatively less explored. When considering baseline Cort and survival probability, two hypotheses have been proposed, the cort-fitness hypothesis and the cort-activity hypothesis. Notwithstanding a few exceptions, studies have generally however shown no relationship between levels of baseline Cort and the probability of survival. Methods: With the aim of increasing our understanding of the effect of baseline Cort on survival probability we utilized mark-recapture data from a long-term study (eight years of capture-mark-recapture) of the Thorn-tailed Rayadito ( Aphrastura spinicauda ), fitting different survival models with and without baseline Cort levels as covariates. Secondly, because the two populations in our study have different values of baseline Cort, we evaluated whether the association between baseline Cort and apparent inter-annual survival probability varied in relation to these two populations. Results: In the high latitude population (the population with lower baseline Cort levels), we observed a quadratic (inverted U-shape) relationship between baseline Cort levels and inter-annual survival probability; in the low latitude population, baseline Cort had no apparent effect on inter-annual survival probability. Conclusions: Because of the quadratic relationship, a relationship that only can be observed with long-term data, our approach emphasizes the importance of using a capture-recapture model. In addition, because the effect of baseline Cort on survival probability was found to be context-dependent, our work also highlights the importance of comparing different populations.


2020 ◽  
Vol 97 (1) ◽  
pp. 3-32
Author(s):  
Robert W. Cherny

The federal art programs of the New Deal produced public art in quantities not seen before or since. Historians have studied many aspects of the New Deal's art programs, but few have considered the long-term history of works produced by them. New Deal art programs produced large numbers of public murals—so many that such murals are often thought of as the typical form of New Deal art. They thus provide readily available examples of the long-term experience of New Deal art. San Francisco has a particularly rich collection of these murals. Some of them have been well cared for over the past eight decades, but public officials have proved negligent stewards—and occasionally destructive stewards—of others. Some of San Francisco's murals were considered so controversial at the time they were created that they were modified or even destroyed. Others became controversial later, with calls for modification or destruction. Some of the latter were covered, some were vandalized, and some have deteriorated. Most of the damaged murals have been restored, sometimes more than once. This article looks at the city's New Deal murals at Coit Tower, the Mothers Building at the Zoo, the Beach Chalet, the University of California San Francisco, the Alemany Health Center, Treasure Island/City College, and Rincon Annex/Center, with special attention to the George Washington High School murals that have recently been highly controversial. Controversies over the murals at Coit Tower, Rincon Annex, and George Washington High School also reveal significant changes in the role of the city's political and civic leadership with regard to public art.


2012 ◽  
Vol 15 (1) ◽  
pp. 4 ◽  
Author(s):  
David M. Holzhey ◽  
William Shi ◽  
A. Rastan ◽  
Michael A. Borger ◽  
Martin H�nsig ◽  
...  

<p><b>Introduction:</b> The goal of this study was to compare the short- and long-term outcomes after aortic valve (AV) surgery carried out via standard sternotomy/partial sternotomy versus transapical transcatheter AV implantation (taTAVI).</p><p><b>Patients and Methods:</b> All 336 patients who underwent taTAVI between 2006 and 2010 were compared with 4533 patients who underwent conventional AV replacement (AVR) operations between 2001 and 2010. Using propensity score matching, we identified and consecutively compared 2 very similar groups of 167 patients each. The focus was on periprocedural complications and long-term survival.</p><p><b>Results:</b> The 30-day mortality rate was 10.8% and 8.4% (<i>P</i> = .56) for the conventional AVR patients and the TAVI patients, respectively. The percentages of postoperative pacemaker implantations (15.0% versus 6.0%, <i>P</i> = .017) and cases of renal failure requiring dialysis (25.7% versus 12.6%, <i>P</i> = .004) were higher in the TAVI group. Kaplan-Meier curves diverged after half a year in favor of conventional surgery. The estimated 3-year survival rates were 53.5% � 5.7% (TAVI) and 66.7% � 0.2% (conventional AVR).</p><p><b>Conclusion:</b> Our study shows that even with all the latest successes in catheter-based AV implantation, the conventional surgical approach is still a very good treatment option with excellent long-term results, even for older, high-risk patients.</p>


2011 ◽  
Vol 14 (4) ◽  
pp. 237 ◽  
Author(s):  
Ferdinand Vogt ◽  
Anke Kowert ◽  
Andres Beiras-Fernandez ◽  
Martin Oberhoffer ◽  
Ingo Kaczmarek ◽  
...  

<p><b>Objective:</b> The use of homografts for aortic valve replacement (AVR) is an alternative to mechanical or biological valve prostheses, especially in younger patients. This retrospective comparative study evaluated our single-center long-term results, with a focus on the different origins of the homografts.</p><p><b>Methods:</b> Since 1992, 366 adult patients have undergone AVR with homografts at our center. We compared 320 homografts of aortic origin and 46 homografts of pulmonary origin. The grafts were implanted via either a subcoronary technique or the root replacement technique. We performed a multivariate analysis to identify independent factors that influence survival. Freedom from reintervention and survival rates were calculated as cumulative events according to the Kaplan-Meier method, and differences were tested with the log-rank test.</p><p><b>Results:</b> Overall mortality within 1 year was 6.5% (21/320) in the aortic graft group and 17.4% (8/46) in the pulmonary graft group. In the pulmonary graft group, 4 patients died from valve-related complications, 1 patient died after additional heterotopic heart transplantation, and 1 patient who entered with a primary higher risk died from a prosthesis infection. Two patients died from non-valve-related causes. During the long-term follow-up, the 15-year survival rate was 79.9% for patients in the aortic graft group and 68.7% for patients in the pulmonary graft group (<i>P</i> = .049). The rate of freedom from reoperation was 77.7% in the aortic graft group and 57.4% in the pulmonary graft group (<i>P</i> < .001). The reasons for homograft explantation were graft infections (aortic graft group, 5.0%; pulmonary graft group, 6.5%) and degeneration (aortic graft group, 7.5%; pulmonary graft group, 32.6%).</p><p><b>Conclusion:</b> Our study demonstrated superior rates of survival and freedom from reintervention after AVR with aortic homografts. Implantation with a pulmonary graft was associated with a higher risk of redo surgery, owing to earlier degenerative alterations.</p>


2015 ◽  
Vol 156 (45) ◽  
pp. 1824-1833 ◽  
Author(s):  
Árpád Illés ◽  
Ádám Jóna ◽  
Zsófia Simon ◽  
Miklós Udvardy ◽  
Zsófia Miltényi

Introduction: Hodgkin lymphoma is a curable lymphoma with an 80–90% long-term survival, however, 30% of the patients develop relapse. Only half of relapsed patients can be cured with autologous stem cell transplantation. Aim: The aim of the authors was to analyze survival rates and incidence of relapses among Hodgkin lymphoma patients who were treated between January 1, 1980 and December 31, 2014. Novel therapeutic options are also summarized. Method: Retrospective analysis of data was performed. Results: A total of 715 patients were treated (382 men and 333 women; median age at the time of diagnosis was 38 years). During the studied period the frequency of relapsed patients was reduced from 24.87% to 8.04%. The numbers of autologous stem cell transplantations was increased among refracter/relapsed patients, and 75% of the patients underwent transplantation since 2000. The 5-year overall survival improved significantly (between 1980 and 1989 64.4%, between 1990 and 1999 82.4%, between 2000 and 2009 88.4%, and between 2010 and 2014 87.1%). Relapse-free survival did not change significantly. Conclusions: During the study period treatment outcomes improved. For relapsed/refractory Hodgkin lymphoma patients novel treatment options may offer better chance for cure. Orv. Hetil., 2015, 156(45), 1824–1833.


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