scholarly journals First indications of a sharp population decline in the globally threatened Spoon-billed Sandpiper Eurynorhynchus pygmeus

2002 ◽  
Vol 12 (1) ◽  
pp. 1-18 ◽  
Author(s):  
P. S. Tomkovich ◽  
E. E. Syroechkovski, Jr. ◽  
E. G. Lappo ◽  
C. Zöckler

Spoon-billed Sandpiper Eurynorhynchus pygmeus is classed as globally Vulnerable, based on the only available population estimate, made in 1977, of 2,000–2,800 pairs. Surveys for breeding Spoon-billed Sandpipers were carried out in summer 2000 on the Anadyr estuary coast, the Chukotka autonomous region, Russia. Although six new breeding sites were found, only 16–17 breeding males/pairs were recorded on the northern coast of the Anadyr estuary and five males/pairs on the southern coast and more southerly lagoons. These numbers were much lower than expected, and the species was not recorded in several apparently suitable areas. Four formerly known breeding sites held only one displaying male between them. At no site was there evidence of an increasing or stable local population. Together with other indicative data these suggest a sharp decline in the population of Spoon-billed Sandpiper. The previous population size estimate obviously requires updating, both because there were some incorrect assumptions in the calculations made for the first population estimate, and also due to a recent population decline. It is likely that the current population numbers under 1,000 breeding pairs. Given that the population of this species may be substantially lower than the only previous estimate, and the evidence for a possible rapid decline in its population described in this paper, it is recommended that its IUCN status is changed from Vulnerable to Endangered. No reasons for the apparent rapid rate of decline are evident within the breeding range. “Bottle-necks” should be looked for at migration sites or wintering grounds, but currently, monitoring of the population is only possible on the breeding grounds.

The Condor ◽  
2007 ◽  
Vol 109 (2) ◽  
pp. 351-360 ◽  
Author(s):  
Joseph R. Jehl

Abstract As late as the 1940s the Semipalmated Sandpiper (Calidris pusilla) was the most abundant sandpiper breeding at Churchill, Manitoba. By the 1960s it had undergone a sharp decline, and by the mid-1990s the local population consisted of 11 pairs in a single colony. Nesting was last documented in 2001. Declines had also become evident at several other breeding sites along the Hudson Bay coast of Manitoba and Ontario, as well as in the number of migrants detected on the Atlantic coast of Canada and the northern United States. Information on the biology of the Churchill population in 1993–2004 largely agreed with that gathered at La Pérouse Bay, Manitoba, in the 1980s: reproductive success was good and new birds continued to join the colony; however, the number of breeding attempts by individuals was low and decreasing. As there is no evidence that the decline was related to local factors (e.g., altered habitats, climate change), it is probably attributable to mortality in the nonbreeding season, which leaves fewer birds available to return north. Whether causality can be fully resolved is problematic. Monitoring migrants can reveal population trends and studies on the breeding grounds can help frame hypotheses, but both approaches are time-consuming and provide only partial answers. In such cases, restoration of declining species may be best served by fostering habitat conservation throughout a species' range.


2019 ◽  
Vol 42 ◽  
pp. 19-27
Author(s):  
Melissa Monthouel ◽  
Svein Dale

The Eurasian Curlew (Numenius arquata) is a species in decline, classified as near threatened (NT) worldwide, and vulnerable (VU) in Norway. In Akershus county, southeastern Norway, the population of breeding Eurasian Curlews was estimated at 50-60 pairs in 1982. No recent update exists of this population size estimate. In this study, we assessed the population size in 2017 in Akershus, and examined how the population size changed between 1971 and 2017 by using historical observation records of Eurasian Curlews. We estimated that there were 30 territories in Akershus in 2017 and found that the population declined by 47% since 1995 and 77% since 1971. In the period 1995-2017, the yearly rate of decline was 2.8%. We discuss possible reasons for the decline, such as intensive agricultural practices, high nest predation rates, and large-scale threats on the wintering grounds.


2021 ◽  
pp. 1-8
Author(s):  
Michael J Liles ◽  
M Nils Peterson ◽  
Kathryn T Stevenson ◽  
Markus J Peterson

Summary Public preferences for wildlife protection can dictate the success or failure of conservation interventions. However, little research has focused on wildlife preferences among youth or how youth prioritize species-based conservation. We conducted a study of youth between 7 and 20 years old (n = 128) at five local schools situated near critical hawksbill turtle (Eretmochelys imbricata) nesting beaches in El Salvador to determine their wildlife preferences and how they prioritize species for conservation based on five attributes: endemism; use for hunting and fishing; rapid decline in population size; presence around their home; and ecological significance. These Salvadoran youth showed preferences for native over non-native species and tended to rank rapid population decline as the most important attribute for prioritizing wildlife for protection, followed by use for hunting and fishing. Participants in local environmental education activities placed greater importance on species in rapid decline than non-participants, who considered endemism as most important. Overall, these findings reveal how environmental education may successfully promote increased prioritization of imperilled species among youth. Economic payments for conserving hawksbill turtles may link the two top reasons that Salvadoran youth provided for protecting species by compensating for the reduced hunting required to facilitate population stabilization.


2019 ◽  
Vol 9 (4) ◽  
pp. 476-483
Author(s):  
L. D. Romanchuk ◽  
L. O. Herasymchuk ◽  
S. P. Kovalyova ◽  
Yu. V. Kovalchuk ◽  
O. V. Lopatyuk

The article provides the assessment of the quality of life of the population resident at the radioactively contaminated areas of the Yemilchyno, Malyn, Korosten, Narodychi, Olevsk, Luhyny and Ovruch raions of the Zhytomyr region. The basis for the study and assessment of the quality of life of the population of radioactively contaminated administrative raions of the Zhytomyr region were the statistical data of the Main Directorate of Statistics in Zhytomyr Region, the Health Directorate of Zhytomyr Region State Administration, as well as our own results of a sociological survey. It was established that for the period between 2002 and 2018, the population of radioactively contaminated areas decreased by 24.7% (maximum values are representative of Malyn and Korosten raions). Natural population decline rates in rural settlements exceeded the corresponding values for urban settlements from 1.4 (Malyn raion) to 13 times (Olevsk raion). There is also the aging of the population, the largest share of the elderly (65 years old and older) - 21.7% and 20.8% are resident in the Korosten and Narodychi raions. The values of birth rates (7.5 (Ovruch raion) - 13 (Olevsk raion) per 1,000 of present population) did not have a positive effect on the demographic situation as a whole because of the high mortality rate exceeding the birth rate by 1.1 (Olevsk raion) - 2.9 times (Malyn raion). The main causes of death are diseases of the circulatory system (75.4%), cancer (10%) and external factors (7.3%). It was noted that there is a deterioration of the health of the local population; they pointed out that diseases related to the ChNPP accident include cardiovascular diseases, diseases of the circulatory, nervous and endocrine systems, diseases of bones and joints, headaches. The living conditions of the population resident at the radioactively contaminated areas of Zhytomyr region are unsatisfactory, which is confirmed by both objective data and subjective assessments of the residents themselves. The housing stock is outdated and it needs renovation. In order to improve the quality of life of the population of radioactively contaminated territories in the Zhytomyr region, it is necessary to reform the state policy, to provide financial support for their revival and creation of normal living and reproduction conditions for the population.


2019 ◽  
Vol 6 (7) ◽  
pp. 190598 ◽  
Author(s):  
Armando M. Jaramillo-Legorreta ◽  
Gustavo Cardenas-Hinojosa ◽  
Edwyna Nieto-Garcia ◽  
Lorenzo Rojas-Bracho ◽  
Len Thomas ◽  
...  

The vaquita ( Phocoena sinus ) is a small porpoise endemic to Mexico. It is listed by IUCN as Critically Endangered because of unsustainable levels of bycatch in gillnets. The population has been monitored with passive acoustic detectors every summer from 2011 to 2018; here we report results for 2017 and 2018. We combine the acoustic trends with an independent estimate of population size from 2015, and visual observations of at least seven animals in 2017 and six in 2018. Despite adoption of an emergency gillnet ban in May 2015, the estimated rate of decline remains extremely high: 48% decline in 2017 (95% Bayesian credible interval (CRI) 78% decline to 9% increase) and 47% in 2018 (95% CRI 80% decline to 13% increase). Estimated total population decline since 2011 is 98.6%, with greater than 99% probability the decline is greater than 33% yr −1 . We estimate fewer than 19 vaquitas remained as of summer 2018 (posterior mean 9, median 8, 95% CRI 6–19). From March 2016 to March 2019, 10 dead vaquitas killed in gillnets were found. The ongoing presence of illegal gillnets despite the emergency ban continues to drive the vaquita towards extinction. Immediate management action is required if the species is to be saved.


The Condor ◽  
2004 ◽  
Vol 106 (1) ◽  
pp. 60-70 ◽  
Author(s):  
R. I. Guy Morrison ◽  
R. Kenyon Ross ◽  
Lawrence J. Niles

AbstractSurveys of the North American race of the Red Knot (Calidris canutus rufa) on its main wintering areas on the coasts of Patagonia and Tierra del Fuego (Argentina and Chile) showed a dramatic decline in the wintering population: totals in 2003 were about 30 000 compared to 67 500 in the mid-1980s. Numbers at the principal wintering site, Bahia Lomas, fell by approximately 50%, from 45 300 in 2000 to 22 000–25 000 in 2002–2003. Numbers at peripheral sites on the coast of Patagonia declined dramatically, decreasing 98% compared to numbers in the mid-1980s. The results showed that declines at core sites did not result from birds moving to other places within the known wintering (or other) areas, but reflected a general population decline, with most birds now restricted to key sites in Tierra del Fuego. This phenomenon may explain why long-term declines noted elsewhere have only recently become apparent at key wintering areas. Possible reasons for the declines are discussed. Banding studies in Delaware Bay have shown that in recent years an increasing proportion of Red Knots is unable to gain sufficient weight for migration to the breeding grounds. This is likely due to reductions in their main food resource, eggs of the horseshoe crab Limulus polyphemus. The resulting increase in mortality could account for the magnitude and severity of the declines we observed.Disminuciones en las Poblaciones Invernantes de Calidris canutus rufa en el Sur de Sur AméricaResumen. Censos de la raza norteamericana de Calidris canutus (rufa) en sus áreas de invernada principales en las costas de la Patagonia y Tierra del Fuego (Argentina y Chile) mostraron una disminución dramática en la población invernante. Los totales en 2003 fueron aproximadamente 30 000, comparados con 67 500 a mediados de los años 80. Los números en el sitio principal de invernada (Bahía Lomas) decayeron en aproximadamente un 50%, de 45 300 en 2000 a 22 000–25 000 en 2002–2003. Los números en sitios periféricos en la costa de Patagonia declinaron dramáticamente, en un 98% en comparación con los números de mediados de los ochenta. Los resultados mostraron que las disminuciones en los sitios núcleo no fueron el resultado de que las aves se movieran a otros sitios dentro del rango invernal conocido, o a otras áreas. En cambio, reflejaron una disminución general de la población; la mayoría de las aves están ahora restringidas a sitios claves en Tierra del Fuego. Este fenómeno podría explicar por qué las disminuciones poblacionales de largo plazo detectadas en otros lugares sólo se han hecho aparentes ahora en las áreas claves de invernada. Se discuten las posibles causas de las disminuciones. Estudios de anillamiento en la bahía de Delaware han mostrado que en años recientes una mayor proporción de las aves es incapaz de incrementar su peso hasta los niveles necesarios para la migración hacia las áreas de invernada. Esto probablemente es debido a reducciones en su principal recurso alimenticio, los huevos de Limulus polyphemus. El incremento en mortalidad resultante podría explicar la magnitud y la severidad de las disminuciones poblacionales que observamos.


2019 ◽  
Vol 54 (4) ◽  
pp. 1802214 ◽  
Author(s):  
Mehrdad Arjomandi ◽  
Siyang Zeng ◽  
Igor Barjaktarevic ◽  
R. Graham Barr ◽  
Eugene R. Bleecker ◽  
...  

The characteristics that predict progression to overt chronic obstructive pulmonary disease (COPD) in smokers without spirometric airflow obstruction are not clearly defined.We conducted a post hoc analysis of 849 current and former smokers (≥20 pack–years) with preserved spirometry from the Subpopulations and Intermediate Outcome Measures in COPD Study (SPIROMICS) cohort who had baseline computed tomography (CT) scans of lungs and serial spirometry. We examined whether CT-derived lung volumes representing air trapping could predict adverse respiratory outcomes and more rapid decline in spirometry to overt COPD using mixed-effect linear modelling.Among these subjects with normal forced expiratory volume in 1 s (FEV1) to forced vital capacity (FVC) ratio, CT-measured residual volume (RVCT) to total lung capacity (TLCCT) ratio varied widely, from 21% to 59%. Over 2.5±0.7 years of follow-up, subjects with higher RVCT/TLCCT had a greater differential rate of decline in FEV1/FVC; those in the upper RVCT/TLCCT tertile had a 0.66% (95% CI 0.06%–1.27%) faster rate of decline per year compared with those in the lower tertile (p=0.015) regardless of demographics, baseline spirometry, respiratory symptoms score, smoking status (former versus current) or smoking burden (pack–years). Accordingly, subjects with higher RVCT/TLCCT were more likely to develop spirometric COPD (OR 5.7 (95% CI 2.4–13.2) in upper versus lower RVCT/TLCCT tertile; p<0.001). Other CT indices of air trapping showed similar patterns of association with lung function decline; however, when all CT indices of air trapping, emphysema, and airway disease were included in the same model, only RVCT/TLCCT retained its significance.Increased air trapping based on radiographic lung volumes predicts accelerated spirometry decline and progression to COPD in smokers without obstruction.


2016 ◽  
Vol 29 (3) ◽  
pp. 209-216 ◽  
Author(s):  
Graham C. Parker ◽  
Kalinka Rexer-Huber ◽  
David Thompson

AbstractPopulations of grey petrels have declined globally due to both incidental capture in commercial fisheries and predation by introduced mammals at breeding sites. In the New Zealand region, grey petrels only breed on Campbell and Antipodes islands. Rats were successfully eradicated from Campbell Island in 2001. We assessed the spatial extent and conducted the first quantitative population estimate of the grey petrel population on Campbell Island and surrounding islets. There was an estimated c. 96 pairs (95% CI: 83, 109) of breeding grey petrels from the four colonies. Since work was conducted during the middle of the chick-rearing stage, this is an underestimate of the breeding population. The Campbell Island grey petrel breeding population remains small. Our study provides a baseline for future population estimates of grey petrels on Campbell Island.


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