scholarly journals Harbor porpoise losing its edges: genetic time series suggests a rapid population decline in Iberian waters over the last 30 years

2021 ◽  
Author(s):  
Yacine Ben Chehida ◽  
Tjibbe Stelwagen ◽  
Jeroen P. A. Hoekendijk ◽  
Marisa Ferreira ◽  
Catarina Eira ◽  
...  

AbstractImpact of climate changes on species is expected to be especially visible at the extremities of the species distribution, where they meet sub-optimal conditions. In Mauritania and Iberia, two genetically isolated populations of harbor porpoises form a distinct ecotype and are presumably locally adapted to the upwelling waters. By analyzing the evolution of mitochondrial genetic variation in the Iberian population between two temporal cohorts (1990-2002 vs. 2012-2015), we report a dramatic decrease in genetic diversity. Phylogenetic analyses including neighboring populations identified two porpoises in southern Iberia carrying a divergent haplotype close to the Mauritanian population, yet forming a distinctive lineage. This suggests that Iberian porpoises may not be as isolated as previously thought with immigration from Mauritania or an unknown population in between, but none from the northern ecotype. The rapid decline in the Iberian mitochondrial diversity may be driven by either genetic drift, or by a dramatic decline in census population size possibly resulting from environmental stochasticity, prey depletion, or acute fishery bycatches. These results illustrate the value of genetics time series to inform demographic trends and emphasize the urgent need for conservation measures to ensure the viability of this small harbor porpoise population in Iberia.

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.


2021 ◽  
Vol 40 ◽  
pp. 140-163
Author(s):  
Ivan N. Bolotov ◽  
Mikhail Y. Gofarov ◽  
Vyacheslav V. Gorbach ◽  
Yulia S. Kolosova ◽  
Alisa A. Zheludkova ◽  
...  

Recent multi-locus phylogenetic studies repeatedly showed that what was thought to be the Clouded Apollo butterfly Parnassius mnemosyne (Linnaeus, 1758) represents a cryptic species complex. This complex contains at least three distant species-level phylogenetic lineages. Here, we compile a set of morphology- and DNA-based evidences supporting the distinctiveness of two species in this group, i.e. P. mnemosyne s. str. and P. nebrodensis Turati, 1907 stat. rev. These species can be distinguished from each other based on a combination of diagnostic characters in the male genitalia structure, wing scale patterns, and the forewing venation. The species status of P. nebrodensis is supported based on unique nucleotide substitutions in the mitochondrial (COI, ND1, and ND5) and nuclear (Wg and EF-1a) genes. P. nebrodensis is endemic to the Western Mediterranean Region. This species shares a disjunctive range through the Pyrenees, Western and Central Alps, Apennines, and the Nebrodi and Madonie mountains on Sicily. Altogether 38 nominal taxa initially described as P. mnemosyne subspecies are considered here to be junior synonyms of P. nebrodensis. At first glance, P. nebrodensis can be assessed as an endangered species due to its restricted distribution, narrow range of habitats, and ongoing population decline. Isolated populations of this species scattered through mountain ranges need special management and conservation efforts.


Oryx ◽  
2007 ◽  
Vol 41 (1) ◽  
pp. 38-43 ◽  
Author(s):  
Youbang Li ◽  
Chengming Huang ◽  
Ping Ding ◽  
Zheng Tang ◽  
Chris Wood

Interviews with local people and a survey were carried out in 23 counties of south-west Guangxi Province from April 2002 to June 2003 to evaluate the conservation status of François' langur Trachypithecus francoisi and assess the extent and nature of threats to the species' survival. François' langurs were found in only 10 counties compared with their presence in 23 counties before 1990. The total population size is estimated to be 307 individuals in 14 isolated populations. This represents a 90% decrease in population size since the early 1980s and an 85% decrease since the mid 1990s. The primary threat to the langur is hunting, mainly for traditional medicine. Our results suggest that conservation efforts for the species have been ineffectual during the last decade and, even within reserves, few direct management measures seem to have been taken to protect and conserve the langurs. Without the instigation of such measures it seems likely that François' langur will disappear both inside and outside reserves. To ensure the long-term survival of Francois' langur in Guangxi Province increased investment and improved management, planning, and training of reserve managers and staff is required, with a particular focus on the key remaining reserves and sites for the langur. Some of this work is now underway.


Oryx ◽  
2010 ◽  
Vol 44 (2) ◽  
pp. 213-218 ◽  
Author(s):  
Martin Dallimer ◽  
Martim Melo

AbstractTerrestrial and freshwater molluscs are amongst the most threatened of all taxa, yet data exist on the distribution and status of only a small proportion of the species. Here we present the results of the first systematic survey of a terrestrial mollusc on the island of Príncipe in the Gulf of Guinea. Archachatina bicarinata has never been previously surveyed, despite being categorized as Vulnerable on the IUCN Red List and suffering from unregulated harvesting for food. We found that A. bicarinata is restricted to primary rainforest and its abundance and probability of occurrence increased as surveyed sites became less accessible. Additional anecdotal evidence from the observations of previous scientific expeditions, local guides and snail harvesters suggested that the species has suffered a dramatic decline in population size and distribution in recent years. We therefore recommend that immediate action be taken to prevent its imminent extinction on Príncipe. The collection of A. bicarinata from protected areas should be banned, as should commercial harvesting and sales. Subsistence collecting should be limited to larger individuals. Our data have been used to inform the management plans for the protected areas on Príncipe and São Tomé, and this should help to ensure the future of A. bicarinata on both islands.


PEDIATRICS ◽  
1994 ◽  
Vol 93 (4) ◽  
pp. 680-681
Author(s):  
Laurence B. Givner ◽  
Charles R. Woods ◽  
Jon S. Abramson

The practice of pediatrics is forever altered when a vaccine is effective in dramatically reducing the incidence of (or even eradicating) an infectious disease. As the targeted disease is rapidly declining in incidence, there are often exciting changes in the practice of pediatrics, with far-reaching effects in the everyday treatment of patients. Such is the case now due to the effectiveness of the conjugated polysaccharide vaccines against Haemophilus influenzae type b (Hib). The resultant rapid decline in the incidence of invasive disease due to Hib during the past several years has been documented in numerous studies.1-3 The effects of this dramatic decline in Hib disease on the approach to children who have (presumed) infectious diseases are the subject of this editorial.


Oryx ◽  
2001 ◽  
Vol 35 (1) ◽  
pp. 14-25 ◽  
Author(s):  
Carel P. van Schaik ◽  
Kathryn A. Monk ◽  
J. M. Yarrow Robertson

AbstractThe Leuser Ecosystem, northern Sumatra, Indonesia, contains the world's largest orang-utan Pongo pygmaeus population. We examine the consequences of the recent wave of forest conversion, and legal and illegal logging, on orang-utan numbers in the Leuser Ecosystem. We review density variation inside the Leuser Ecosystem and its causes, and the consequences of selective logging, exhaustive logging and clear-felling for habitat conversion on orang-utan densities. The analysis of the orang-utan's decline is based on information on forest loss, logging intensity, and the delineation of logging concessions and legal changes in land use status. The results indicate a very rapid decline, by c. 45 per cent, from c.. 12,000 in early 1993, over a 6- to 7-year period. During 1998 and 1999, losses occurred at a rate of about 1000 orang-utans per year. At this rate, further losses in the near future are expected to put the survival of Leuser's orang-utans in serious doubt.


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.


Oryx ◽  
2014 ◽  
Vol 49 (3) ◽  
pp. 529-534 ◽  
Author(s):  
Chunfa Zhou ◽  
Jiliang Xu ◽  
Zhengwang Zhang

AbstractThe current status and distribution of the Vulnerable Reeves's pheasant Syrmaticus reevesii, endemic to central China, is poorly known. To obtain updated information on its status we selected 89 candidate sites in six provinces and one municipality in central China and conducted interviews and field surveys from April 2011 to April 2012. Interviews demonstrated the pheasant has disappeared from 46% of the surveyed sites. Our results also revealed a population decline at 46 sites, including protected areas, although population densities in protected areas were higher than those in non-protected areas. Eighty-three, 26 and 20% of the surveyed sites had evidence of poaching, habitat loss and use of poison, respectively, which were the three major threats to this species. To ensure the long-term survival of Reeves's pheasant in China, protection and management need to be enforced in both protected and non-protected areas. We recommend that this species should be upgraded to a national first-level protected species in China and recategorized as Endangered on the IUCN Red List.


2010 ◽  
Vol 20 (2) ◽  
pp. 95-111 ◽  
Author(s):  
CHRISTOPH ZÖCKLER ◽  
EVGENY E. SYROECHKOVSKIY ◽  
PHILIP W. ATKINSON

SummaryThe Spoon-billed Sandpiper Eurynorhynchus pygmeus (IUCN Category: Critically Endangered) is in rapid decline. Data from across the entire breeding range (Chukotka and Koryakya in the Russian far north-east) and especially from the well-studied southern core breeding area at Meinypilgyno, confirm the continuing strong decline. At four breeding sites, where more than two counts were available for analysis, the decline was estimated at 26% per annum between 2002 and 2009, or an 88% decline over this period. Allowing for unsurveyed areas, this equates to a decline from a total population of approximately 1,000 breeding pairs in 2000 to 120–220 in 2009. Breeding studies at Meinypilgyno in 2003–2007 (not 2006) showed that the proportion of nests hatching at least one chick was 0.65 and once chicks left the nest, the mean brood size of chicks up to one week old was 1.99. Where it was possible to follow broods, 0.61 chicks fledged per nesting attempt. Survival and recruitment analysis of birds ringed at Meinypilgyno indicated that annual adult survival did not significantly differ over the 2003–2009 study but that recruitment in to the adult breeding population was effectively zero in all but one year of the study (2005). Resighting data for the last two years of the study were sparse due to very low numbers of marked adults being recorded and survival rates over the last 2–3 years of the study must therefore be treated with caution. The analysis therefore indicated that after fledging, survival during immaturity must be very low, leading to a low (or no) recruitment into an ageing population. Recent observations collated from the non-breeding areas confirm the declining trend observed in the breeding areas and imply that the main threats to the population lie along the migration route or in the wintering areas. These are poorly known although hunting in the wintering areas has been identified as a major mortality factor. Other threats include major loss of their intertidal habitats, and collection of birds on the breeding areas by specimen collectors. Improved monitoring in both the breeding and non-breeding areas as well as research on juvenile survival is recommended. Concerted international conservation action is essential if this species is to avoid extinction. This requires (i) improved understanding of the main wintering and staging areas and associated threats; (ii) addressing those threats that can be tackled with immediate effect, such as hunting; (iii) continued long-term monitoring on the breeding areas; (iv) an exploration of other potential breeding areas; (v) conservation action at all important stop-over and wintering sites along the entire flyway and (vi) consideration of a captive-breeding programme to ensure the survival of this species.


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