scholarly journals Variable effects of a changing climate on lay dates and productivity across the range of the Red-cockaded Woodpecker

The Condor ◽  
2019 ◽  
Author(s):  
Stephanie M DeMay ◽  
Jeffrey R Walters
Keyword(s):  
Habitat Management ◽  
Bird Species ◽  
Local Conditions ◽  
Climate Conditions ◽  
Changing Climate ◽  
Spring Temperatures ◽  
Red Cockaded Woodpecker ◽  
Pinus Spp ◽  
Over Time

Abstract Many temperate bird species are breeding earlier in response to warming temperatures. We examined the effects of climate on breeding phenology and productivity in 19 populations across the range of the Red-cockaded Woodpecker (Dryobates borealis), an endangered species endemic to pine (Pinus spp.) forests in the southeastern United States. Red-cockaded Woodpeckers nested earlier in warmer springs and delayed nesting in wetter springs. Earlier nesting and larger group sizes resulted in higher productivity. Spring temperatures have warmed over time across the range, but this has not led to range-wide advances in nesting date over time. Coastal and northern populations have exhibited a trend of earlier nesting over time, but the response of inland populations has been variable, including some populations in which nesting has become later over time. Geographic patterns included high and increasing productivity at higher latitudes, and declining productivity in the southwestern portion of the range, suggesting a possible shift in acceptable climate conditions for the species. Earlier nesting over time was associated with increasing productivity at higher latitudes, while elsewhere earlier nesting over time was associated with declining or stable productivity, suggesting that populations differ in their ability to adjust to a changing climate. The Red-cockaded Woodpecker is a habitat specialist heavily reliant on habitat management and has little capacity to shift its range, so its long-term viability will depend on its ability to adjust in place to changing local conditions.

scholarly journals Impacts of survival and reproductive success on the long-term population viability of reintroduced great bustards Otis tarda in the UK

Oryx ◽  
2015 ◽  
Vol 50 (4) ◽  
pp. 583-592 ◽  
Author(s):  
Kate Ashbrook ◽  
Andrew Taylor ◽  
Louise Jane ◽  
Ian Carter ◽  
Tamás Székely
Keyword(s):  
Habitat Management ◽  
Bird Species ◽  
Population Viability ◽  
Adult Survival ◽  
Wild Populations ◽  
Great Bustard ◽  
Otis Tarda ◽  
Demographic Rates ◽  
The Uk

AbstractReintroductions aim to re-establish species within their historical ranges through the release of wild- or captive-bred individuals following extirpation (or extinction) in the wild. There is no general agreement on what constitutes a successful reintroduction but the probability of the population achieving long-term persistence should be addressed. Here we review a 10-year trial reintroduction of the great bustard Otis tarda, a globally threatened bird species, to the UK and assess the long-term population viability. Despite changes in rearing and release strategy, initial post-release survival probability remained consistently low, with only 11.3% of bustards (n = 167) surviving from release to 1 year post-release. Nineteen breeding attempts were made by eight females; however, only one chick survived > 100 days after hatching, and no wild juveniles have recruited into the population. Using demographic rates from the UK population and wild populations elsewhere, and stochastic population modelling, we investigate the viability of this reintroduced population by predicting population size over the next 10 years. Under current demographic rates the population was predicted to decline rapidly. Self-sufficiency was predicted only using the highest estimates from the UK population for first-year and adult survival, and recruitment rates from wild populations elsewhere. Although changes have been made in rearing, release strategies, habitat management and release sites used, these changes appear to have a modest effect on long-term viability. Substantial improvements in survival rates and productivity are necessary to establish a viable great bustard population in the UK, and we consider this unlikely.

scholarly journals Long-term changes in the breeding biology of a New Zealand bellbird population suggest plasticity in life-history responses to ecological restoration

2021 ◽  
Author(s):  
Michelle M. Roper ◽  
M.T. Harmer Aaron ◽  
Dianne H Brunton
Keyword(s):  
Life History ◽  
New Zealand ◽  
Reproductive Success ◽  
Ecological Restoration ◽  
Breeding Biology ◽  
Life History Strategies ◽  
Local Conditions ◽  
Anthornis Melanura ◽  
Over Time

AbstractEcological restoration projects provide excellent opportunities to study how animals adapt their life-history strategies in response to changeable environments. A fundamental way animals can optimise reproductive success in changing conditions is trading-off aspects of their breeding system. The New Zealand bellbird (Anthornis melanura) has had a long-term presence on the small restoration island, Tiritiri Matangi Island (Tiri), spanning the island’s degraded agricultural past to its current extensively restored state. We studied the breeding biology of this bellbird population to assess how their reproductive life-history strategies have responded over time to the restoration on Tiri. We compared the current breeding data (2012–2016) of the bellbirds with data from between 2001–2010 (including Baillie, 2011, Cope, 2007), and from 1977–1978 (Anderson and Craig, 2003), prior to the island’s restoration. We also explored associations between abiotic/biotic factors and bellbird reproductive success for the most recent period (2012–2016). Our main finding was that clutch size significantly declined over time from a mean of 3.6 to 2.4 eggs per nest and this decline correlated with increasing population density. This is consistent with a density dependent effect, although further data are required to empirically test this conclusion. Overall, the earliest spring laying dates were in late August and the latest extended to January, with all chicks fledged by the end of February. Nest success was 47% (range 40 – 54%) across 2012–2016, falling within a similar range as previous studies. We found little effect of year, weather, parental age or morphometrics on reproductive success. We observed directional change in patterns of parental investment between 1977–1978 and 2012–2016; in 2012–2016, parents persisted with raising single broods rather than abandoning and re-nesting to raise larger broods. These results suggest that the bellbirds’ life-history traits are plastic in response to local conditions which provides an advantage when repopulating a regenerating or changing habitat.

How retrogressive thaw slumps change over time - a study from Herschel Island (Canada) using 3D electrical resistivity tomography (ERT)

2021 ◽  
Author(s):  
Saskia Eppinger ◽  
Michael Krautblatter
Keyword(s):  
Electrical Resistivity ◽  
Electrical Resistivity Tomography ◽  
Rapid Change ◽  
Yukon Territory ◽  
Resistivity Tomography ◽  
Climate Conditions ◽  
Internal Structures ◽  
Field Campaigns ◽  
Over Time

<p>Retrogressive thaw slumps (RTS) are a common thermokarst landform along arctic coastlines with an increasing thermoerosional activity. They underlay a rapid change in topographical as well as internal structures due to various external factors, e.g. changing climate conditions.</p><p>In 2011 and 2019 electrical resistivity tomography (ERT) measurements were carried during field campaigns to Herschel Island (Yukon Territory, Canada). Transects crossing Herschel Islands largest slump were performed, as well as quasi 3D-ERT-profiles. For better understanding these changes we compared the datasets focusing on the internal structures just as variations in the topography.</p><p>The aim for our study is gaining an impression of structural and topographical changes over several years, leading towards a better comprehension of long-term processes in retrogressive thaw slumps.</p>

scholarly journals Long-term phenology of two North American secondary cavity-nesters in response to changing climate conditions

2019 ◽  
Vol 106 (9-10) ◽  
Author(s):  
Tyler E. Wysner ◽  
Andrew W. Bartlow ◽  
Charles D. Hathcock ◽  
Jeanne M. Fair
Keyword(s):  
Reproductive Output ◽  
Bird Species ◽  
Spring Temperature ◽  
Climate Conditions ◽  
Changing Climate ◽  
Climate Niche ◽  
Cavity Nesters ◽  
Breeding Time ◽  
Phenological Shifts ◽  
Western Bluebirds

Abstract Wildlife populations can respond to changes in climate conditions by either adapting or moving to areas with preferred climate regimes. We studied nesting responses of two bird species, western bluebird (Sialia mexicana) and ash-throated flycatcher (Myiarchus cinerascens), to changing climate conditions (i.e., rising temperatures and increased drought stress) over 21 years in northern New Mexico. We used data from 1649 nests to assess whether the two species responded to changing climate conditions through phenological shifts in breeding time or shifts in nesting elevation. We also examined changes in reproductive output (i.e., clutch size). Our data show that western bluebirds significantly increased nesting elevation over a 19-year period by approximately 5 m per year. Mean spring temperature was the best predictor of western bluebird nesting elevation. Higher nesting elevations were not correlated with hatch dates or clutch sizes in western bluebirds, suggesting that nesting at higher elevations does not affect breeding time or reproductive output. We did not observe significant changes in nesting elevation or breeding dates in ash-throated flycatchers. Nesting higher in elevation may allow western bluebirds to cope with the increased temperatures and droughts. However, this climate niche conservatism may pose a risk for the conservation of the species if climate change and habitat loss continue to occur. The lack of significant changes detected in nesting elevation, breeding dates, and reproductive output in ash-throated flycatchers suggests a higher tolerance for changing environmental conditions in this species. This is consistent with the population increases reported for flycatchers in areas experiencing dramatic climate changes.

Effects of habitat management can vary over time during the recovery of an endangered bird species

2015 ◽  
Vol 192 ◽  
pp. 154-160 ◽  
Author(s):  
Stefanie A. Hartmann ◽  
Gernot Segelbacher ◽  
Mery E. Juiña ◽  
H. Martin Schaefer
Keyword(s):  
Habitat Management ◽  
Bird Species ◽  
Over Time

Enhancing community welfare through improved water quality: a case for applying staggered pollution charges in the river Musi sub-basin of Andhra Pradesh, India

Water Policy ◽  
2005 ◽  
Vol 7 (5) ◽  
pp. 469-483
Author(s):  
Tishya Chatterjee
Keyword(s):  
Andhra Pradesh ◽  
Relevant Literature ◽  
Pollution Prevention ◽  
Economic Benefits ◽  
Environmental Damage ◽  
Marginal Costs ◽  
Community Acceptance ◽  
Level Data ◽  
Over Time

In conditions of severe water-pollution and dormant community acceptance of accumulating environmental damage, the regulator's role goes beyond pollution prevention and more towards remediation and solutions based on the community's long-term expectations of economic benefits from clean water. This paper suggests a method to enable these benefits to become perceptible progressively, through participatory clean-up operations, supported by staggered pollution charges. It analyses the relevant literature on pollution prevention and applies a cost-based “willingness to pay” model, using primary basin-level data of total marginal costs. It develops a replicable demand-side approach imposing charge-standard targets over time in urban-industrial basins of developing countries.

The Short-Term and Long-Term Impacts of Sarbanes-Oxley Act on Composition and Characteristics of Corporate Board of Directors

2015 ◽  
Vol 5 (4) ◽  
Author(s):  
Halil Kaya ◽  
Gaurango Banerjee
Keyword(s):  
Board Composition ◽  
Corporate Boards ◽  
Corporate Accountability ◽  
Corporate Board ◽  
Short Term ◽  
Dual Roles ◽  
Board Characteristics ◽  
Sarbanes Oxley ◽  
Over Time

The paper examines the Sarbanes-Oxley (2002) Acts immediate impact on board composition and characteristics as well as possible reversals in its impact over time. Effects on directors age and tenure are analyzed over the 2001-06 sample period. Female participation in corporate boards is also studied in the pre-SOX and post-SOX periods. The dual roles of directors in being a member of the board as well as serving as either CEO, CFO, Chairman, Co-Chair, Founder, or Lead Director of their respective companies is also examined. We observe a short-term impact of SOX on board compositions due to changes seen in board characteristics between 2001 (pre-SOX), and 2003-05 short-term period (post-SOX). Also, we observe a reversal of board characteristics in 2006 to pre-SOX levels implying that the effects of SOX on board composition were short-lived, and needs to be monitored over time to ensure adherence to corporate accountability guidelines over the long-term.

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