Are green turtles globally endangered?

Aim  To examine the exploitation, recovery and current status of green turtles ( Chelonia mydas ) nesting at Ascension Island.
Location  Ascension Island (UK) (7°57' S, 14°22' W), South Atlantic Ocean.
Methods  We analysed records of the harvest of green turtles nesting at Ascension Island between 1822 and 1935, illustrating the decline in numbers over this period. Using a deterministic age-class structured model we predict the initial number of breeding females present in the population prior to the recorded harvest and compare this to our estimate of the current population based upon our recent annual surveys (1999–2004).
Results  Prior to 1822 we estimate the nesting population of green turtles to have been at least 19,000–22,000 individuals in order for the population to have survived the level of harvest recorded. From recent data (1999–2004), we estimate the current breeding population of green turtles at this site to be 11,000–15,000 females. Our results illustrate a dramatic recovery of the population, which is still increasing exponentially and shows no evidence of slowing, suggesting it has not reached 50% of its carrying capacity.
Main conclusions  We estimate that, since the 1970s, the Ascension Island population of green turtles has increased by 285% and question the recent listing of this species as endangered by the IUCN (World Conservation Union), in particular in the Atlantic Ocean, where 75% of the populations assessed by the IUCN are increasing. Indeed, we estimate the global population of this species to be in excess of 2.2 million individuals. We suggest that the IUCN's global listing process detracts attention from those populations that are truly threatened with extinction and should not, in its present form, be applied to globally distributed long-lived species such as marine turtles.     

福建东山岛海域斑鰶生态的研究

本文研究了福建东山岛附近海域斑生物量、密度的分布及其季节变化;生长和死亡特点;摄食和生殖习性。其平均月生物量为２２２．１ｋｇ／ｋｍ２,占游泳生物月总生物量的２７．２２％,成为优势种;生物量和密度冬季最高,分别为５２４．９ｋｇ／ｋｍ２和９３３２尾／ｋｍ２,比最低的春季高２２．７７倍和８６．２１倍。分布区域性差异明显,东山湾内高达４３８．２ｋｇ／ｋｍ２和７４０５尾／ｋｍ２,比湾外高７７．７１倍和６８．３８倍;渔获由０～Ⅳ龄组构成,ｌ龄组为优势,叉长分布范围为１１１～２２３ｍｍ,以１４１～１６０ｍｍ组为优势;食料以硅藻类的菱形藻、海线藻、圆筛藻、直链藻和骨条藻的数量最多,并大量摄食有机碎屑;初次性成熟的最小年龄为１龄．最小叉长雌性为１４６ｍｍ,雄性１４０ｍｍ。雌雄性均在１５１～１７０ｍｍ组成熟,生殖期在冬季至初春;生长参数为Ｌ∞＝２４６．３７ｍｍ,Ｗ∞＝１８２．６５ｇ,ｋ＝０．４３０３,ｔｏ＝－０．８６４９,体重生长拐点年龄人ｔｒ＝１．６０１７龄;瞬时总死亡率为１．２０１６。关键词     

海南属种新纪录——中华山蝠的回声定位信号、栖息地及序列分析

2007年11月,在海南岛脊椎动物调查过程中,于南部陵水黎族自治县一处电线杆内捕到1只雄性蝙蝠标本,通过形态特征和线粒体DNA ND1基因序列鉴定,确认为蝙蝠科（Vespertilionidae）山蝠属（Nyctalus）的中华山蝠（N. plancyi）,该属、该种均为海南省翼手目新纪录。其主频为33－34 kHz,脉冲持续1.3－1.9 ms;栖息于电线杆内;与四川中华山蝠DQ435074的ND1一致度达到99%。     

First report of the oriental mosquito Aedes albopictus on the West African island of Bioko,Equatorial Guinea

The invasive oriental mosquito Aedes (Stegomyia) albopictus (Skuse) (Diptera: Culicidae) was detected on Bioko Island for the first time in November 2001. It was found to be well established breeding in artificial containers at Planta, near Malabo, the capital of Equatorial Guinea. Associated species of mosquito larvae were Aedes aegypti (L.), Ae. africanus (Theobald), Culex near decens Theobald, Cx. duttoni Theobald, Cx. quinquefasciatus Say, Cx. tigripes De Grandpré & De Charmoy, Eretmapodites quinquevittatus Theobald and Mansonia africana (Theobald). This is the third tropical African country to be invaded by Ae. albopictus, which has recently spread to many parts of the Americas and Europe--with vector competence for dengue, yellow fever and other arboviruses. In the Afrotropical environment, it will be interesting to monitor the ecological balance and/or displacement between introduced Ae. albopictus and indigenous Ae. aegpyti (domestic, peri-domestic and sylvatic populations).     

Lateglacial and Holocene vegetation change on the Isle of Skye: new data from three coastal locations

Detailed lithostratigraphical and biostratigraphical studies from three contrasting coastal sites on the Isle of Skye were undertaken to investigate spatial variations in vegetation development on the island since the Lateglacial. The pollen profiles were then compared with the published pollen data for Skye. The new data reveal broadly similar trends for the sites studied and show that these correspond well to the previously established chronology. A date of ca. 10110 radiocarbon years B.P. has been obtained for the rational rise in Corylus, a date of ca. 8850 uncal B.P. for the appearance of Ulmus and a date of ca. 6600 uncal B.P. for the rise in Alnus. However, significant variations were evident and these were due to (a) coastal proximity, which directly affects vegetation composition through the low but persistent presence of Armeria and Chenopodiaceae, (b) altitude, which determines the effect of rising groundwater that may be related to relative sea level rise, and (c) aspect and position in relation to central Cuillin mountain range, through exposure to SW winds that restrict the development of thermophilous woodland and encourage the acidification of heathlands and development of herb-rich grasslands from ca. 4000 B.P.. This study reveals that the range of variation caused by these local factors is as great as the variation found throughout the island. This has negative implications for the reconstruction of regional patterns of vegetation change but highlights the range of local habitats and wild resources available to early inhabitants of the island.     

The population of the hypogeous fungus<Emphasis Type="Italic"> Tuber aestivum</Emphasis> syn.<Emphasis Type="Italic"> T. uncinatum</Emphasis> on the island of Gotland

The aim of our study was to examine the genetic variation within Tuber aestivum on the Baltic island of Gotland, Sweden. Variation in such a limited geographical area should help illuminate the dispersal abilities of T. aestivum. Knowledge of the genetic variation in this northern outpost could also be useful in the selection of inoculum for the establishment of truffle orchards. Genetic structure and homogeneity of the population were studied using principal component and parsimony analyses of randomly amplified polymorphic DNA data. Our inventories showed that T. aestivum is abundantly distributed in suitable habitats on Gotland. The genetic variation observed suggests sexual reproduction and slow dispersal on the island. It is possible that the present population was established from one introduction, which may be due to ability to survive in this habitat rather than to rare colonising events. The T. aestivum population on Gotland may be an ecotype adapted to the climate and soil conditions on the island.     

Taxonomy and biogeography of Australian species of the Ropalidia stigma group and R. variegata group (Hymenoptera: Vespidae)

The taxonomy of the Australian species of two Ropalidia species groups, the R. stigma group and R. variegata group, is revised and their distribution patterns are discussed. Two species in the R. stigma group (R. darwini and R. elegantula), and four species in the R. variegata group (R. flavinoda, R. gregaria, R. mutabilis and R. revolutionalis) are recognized in Australia, with a new synonymy of R. mutabilis torresiana Richards, 1978, under R. gregaria (de Saussure, 1854). Icaria torrida Smith, 1863, from Seram Island is synonymized with R. unicolor (Smith, 1859).     

Assessing Herbivory Rates of Leaf-Cutting Ant (Atta colombica) Colonies Through Short-Term Refuse Deposition Counts

Leaf-cutting ants (genera Atta and Acromyrmex ) are considered dominant herbivores of Neotropical forests. However, so far quantitative, long-term, and large-scale assessments of their impact on these ecosystems are rare, because the available assessment methods were laborious and/or destructive. We describe a rapid, nondestructive, and inexpensive method to estimate the long-term harvest of Atta colombica colonies. Workers of A. colombica dump the colony refuse (exhausted fungal substrate) outside the nest. A single trail connects the refuse pile and the nest. In contrast to the foraging activity, the refuse deposition rate (the number of deposited refuse particles per minute) is diurnally constant and varies little on subsequent days. The number of refuse particles deposited per day was tightly correlated with the number of harvested fragments in nests of differing sizes ( R ²= 0.77, P < 0.0001). Therefore, the daily harvest of a particular colony can be calculated from short-term counts (5 min) of the refuse deposition rate at any time of the day. Combining these data with information on average fragment size (weight and/or area) allows the calculation of the total daily amount of biomass and/or foliage area harvested by the colony. This new method facilitates quantifying A. colombica herbivory on scales of populations and ecosystems, or over long-term scales.     

A NEW SPECIES OF THE SPHENODONTIAN REPTILE CLEVOSAURUS FROM THE LOWER JURASSIC OF SOUTH WALES

Abstract:  Small reptiles from the Early Jurassic Pant 4 fissure fill in Glamorgan, South Wales (St. Bride's Island, Pant Quarry), were formerly provisionally attributed to three species of sphenodontian lepidosaurs. A re-analysis, aided by new material, has found this herpeto-fauna to consist almost exclusively of a single new species, Clevosaurus convallis sp. nov . , with only one specimen referable to Sphenodontia incertae sedis . Clevosaurus is known from the Upper Triassic and Lower Jurassic in various parts of the world, but C. convallis represents the first occurrence of the genus in the Jurassic of Britain. The material is fragmentary but includes numerous premaxillae, maxillae, dentaries and palatines, and the new species is distinguished by the unique combination of six large additional dentary teeth and a very short nasal process of the premaxilla, along with the diagnostic Clevosaurus features.