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1.
  1. Impacts of alien invasive species on island communities and ecosystems may be even more detrimental than on the mainland. Therefore, since the 1950s, hundreds of restoration projects have been implemented worldwide, with the aim of controlling or eradicating alien species from islands. To date, no review has been focused on eradication on Mediterranean islands. To fill the gap, I reviewed the available information concerning mammal eradications so far carried out on Mediterranean islands, examining the details of several aspects of project implementation and monitoring.
  2. I obtained data for 139 attempted eradications on 107 Mediterranean islands in eight countries, with Greece, Italy, and Spain accounting for the highest number. Eradication projects targeted 13 mammal species. The black rat Rattus rattus was the target of over 75% of the known attempted eradications in the Mediterranean Basin; other species targeted were feral goat Capra hircus, house mouse Mus musculus, European rabbit Oryctolagus cuniculus, and domestic cat Felis catus. The most widely adopted technique was poisoning (77% of all eradications), followed by trapping (15%) and hunting (4%). However, techniques were largely target-specific.
  3. The average failure rate was about 11%. However, this percentage varied according to the specific mammalian order, and eradications of Carnivora failed more often than those of other mammals. Among rodents, house mouse eradication attained a very high failure rate (75%). Reinvasion occurred after 15% of successful eradications.
  4. A better understanding of the motivations of animal rights activists may improve the chance of success when eradicating charismatic or domesticated species. Furthermore, it is crucial to collect data and case studies about reinvasions, in order to strengthen biosecurity programmes following eradication. As in other parts of the world, the next frontier in alien mammal management on Mediterranean islands concerns the eradication of invasive species from inhabited islands.
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2.
Little is known about the role of migratory waterfowl in the long‐distance dispersal (LDD) of seeds. We studied the gut contents of 42 teals Anas crecca collected in the Camargue, southern France, and found intact seeds of 16 species. There was no relationship between the probability that a given seed species was found intact in the lower gut, and the seed hardness or size. The number of seeds found in the oesophagus and gizzard (a measure of ingestion rate) was the only significant predictor of the occurrence of intact seeds in the lower gut, so studies of waterfowl diet can be used as surrogates of dispersal potential. In a literature review, we identified 223 seed species recorded in 25 diet studies of teal, pintail Anas acuta, wigeon A. penelope or mallard A. platyrhynchos in Europe. We considered whether limited species distribution reduces the chances that a seed can be carried to suitable habitat following LDD. Overall, 72% of plant species recorded in duck diets in southern Europe (36 of 50) were also recorded in the north, whereas 97% of species recorded in duck diets in the north (137 of 141) were also recorded in the south. This suggests a great potential for LDD, since most dispersed plants species occur throughout the migratory range of ducks. Migratory ducks are important vectors for both terrestrial and aquatic plant species, even those lacking the fleshy fruits or hooks typically used to identify seeds dispersed by birds. Finally, we show ducks are important vectors of exotic plant species. We identified 14 alien to Europe and 44 native to Europe but introduced to some European countries whose seeds have been recorded in duck diet.  相似文献   

3.
Eradications of invasive alien species have generally benefited biodiversity. However, without sufficient planning, successful eradications can have unexpected and unwanted consequences for native species and ecosystems. In particular, the “surprise effect” is the rapid increase of hitherto unnoticed species following the sudden removal of an invasive alien that was exerting an ecological force on those species (predation, competition or herbivory, for example). The only way to prevent these undesired outcomes is to adapt the control programme following the characterization of the trophic relationships between the invasive alien species and the invaded communities, that is, to view the control with a holistic perspective. Here, we illustrate this point with the study of the role of the ship rat (Rattus rattus), which invaded a tropical pacific atoll, Surprise Island, New Caledonia. We assessed the risk of surprise effects during a pre-eradication phase of several years, and then adapted our eradication strategy accordingly.  相似文献   

4.
Although the value of noncrop vegetation for biological control has been extensively studied in agricultural landscapes, there are few reports on how it functions mechanistically. When focusing on the pest control function provided by noncrop vegetation, tritrophic interactions among a predatory natural enemy, its prey, and the prey’s host plant need to be examined. In Japan, the multicolored Asian ladybird beetle, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), an aphidophage, serves as a natural pest control agent in agricultural production, although the species’ introduction into Europe and North America for pest control has had a negative impact on native ecosystems. In the present study, 33 aphid–plant pairs from an agricultural landscape in the eastern Kanto region of Japan were examined experimentally for initial larval survivorship and development of H. axyridis. Significant differences were found among plant–aphid pairs with regard to these parameters. In addition, the larval survivorship of H. axyridis was not consistently determined by host plant or aphid species alone but was context-dependently influenced by the aphid–plant combination. Some alien host plants showed positive effects on the ladybird beetle. Others, however, served as hosts for unsuitable prey species, such as the competitive alien plants Solidago canadensis L. and Robinia pseudoacacia L., which are the host plants of Uroleucon nigrotuberculatum (Olive) and Aphis craccivora Koch, respectively. These findings suggest that various noncrop plants could be managed to promote ladybird beetle populations in rural landscapes.  相似文献   

5.
We present necessary and sufficient conditions on the stability matrix of a general n(≥2)-dimensional reaction-diffusion system which guarantee that its uniform steady state can undergo a Turing bifurcation. The necessary (kinetic) condition, requiring that the system be composed of an unstable (or activator) and a stable (or inhibitor) subsystem, and the sufficient condition of sufficiently rapid inhibitor diffusion relative to the activator subsystem are established in three theorems which form the core of our results. Given the possibility that the unstable (activator) subsystem involves several species (dimensions), we present a classification of the analytically deduced Turing bifurcations into p (1 ≤p≤ (n− 1)) different classes. For n = 3 dimensions we illustrate numerically that two types of steady Turing pattern arise in one spatial dimension in a generic reaction-diffusion system. The results confirm the validity of an earlier conjecture [12] and they also characterise the class of so-called strongly stable matrices for which only necessary conditions have been known before [23, 24]. One of the main consequences of the present work is that biological morphogens, which have so far been expected to be single chemical species [1–9], may instead be composed of two or more interacting species forming an unstable subsystem. Received: 21 September 1999 / Revised version: 21 June 2000 / Published online: 24 November 2000  相似文献   

6.
Survival of broad-leaved dock (Rumex obtusifolius) plants exposed to grass (mainly Festuca rubra and Elymus repens) competition in unmanaged grassland in Central Europe was investigated. Individual plants (n = 244) were marked in a 35 × 28 m experimental plot divided into 20 quadrats. The mortality of the dock plants was recorded twice a year, and plant size (number of flowering stems) recorded for 8 years (2000–2007). Half of the plants died within 4 years and 4% survived to the end of the experiment. On average, winter mortality (October–April, 60%) was greater than summer mortality (May–September, 40%) but both varied between years. The plants decreased in size as they approached death. The survival of dock plants in particular quadrats was negatively correlated with the biomass of grass roots and rhizomes. Intensity of below-ground competition and possibly water deficiency contributed most to dock mortality.  相似文献   

7.
Loggerhead turtle Caretta caretta nesting in Italy had been reported to be limited to the Pelagian Islands and only sporadically elsewhere. As presence of loggerhead turtle nests had occasionally been reported (1988–1999) along about 200 km of the Ionian coast of Calabria, we carried out a project to assess the actual state of the nesting population between 2000 and 2004. We divided the coastline in two sectors (A: 52 km, and B: 146 km) that were monitored from mid-June to end of July for a total of n = 174 monitoring days and 1,813.6 km patrolled on foot with different intensities (extensive versus intensive). In sector B, through extensive monitoring we did not find any emergence tracks, but in sector A by intensive survey (2002–2004: one survey/3.64 days) we detected 3–8 nests/year. In total, 25 nests (both observed and reported), were recorded in our study area, and an assessment of a total of 15–16 nests/year was suggested. These figures, within the national scenario depicted from the review of known nesting events in the last 40 years (88 records concerning more than 143–144 nests), show that loggerhead turtle nesting has been underestimated in Italy, due to inadequate monitoring protocols, and that nesting is more frequent than expected (at least 30–40 nests/year). Conservation strategies in Italy should then focus not only on the reduction of mortality at sea, but also include large-scale actions to preserve scattered (but regular) nesting events.  相似文献   

8.
During the vegetation periods of 2001–2003 Heteroptera associated with the invasive alien tall goldenrods Solidago canadensis and S. gigantea were studied in seven model habitats in the north-eastern part of the Czech Republic. Heteropterans associated with adjacent growths were also studied in 2002–2003. A set of 3,042 specimens of 127 samples was analyzed with the aim of estimating average species richness, abundance and trophic structure of the heteropteran assemblages of the studied plant stand. On alien Solidago, 68 heteropteran species were recorded and 71 species were collected in the stands adjacent to the tall goldenrods with 48 shared species. Despite the nearly indentical species richness and similar abundances in Solidago and adjacent stands, there are differences in the trophic structure. The majority of the shared species and species found on Solidago canadensis only are polyphagous contrary to the majority of stenophagous species found on Solidago free stands only. Only a small proportion of heteropteran species that were recorded on alien Solidago stands are specialized to Asteraceae and their abundance was mostly low. Only the lygaeid Nysius senecionis, an Asteraceae specialist, occured in masses on S. canadensis in sunny and warm habitats. Similarly, predatory Orius minutus and O. niger reached high abundance values in Solidago stands compared to adjacent stands.  相似文献   

9.
Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) is native to Asia, and was widely introduced as a biocontrol agent of aphids and coccids in Europe and North America. In Europe H. axyridis is considered to be an invasive alien species. Although not known to have been deliberately introduced to Great Britain, it was first recorded there in 2004, in south-east England. Harmonia axyridis arrived in Great Britain by various means, primarily from mainland Europe, but also from Canada. Extensive national and local media coverage, and a dedicated website (), facilitated public involvement in recording H. axyridis in Great Britain; in excess of 4,000 verified records of the species were received between 2004 and 2006. Through detailed mapping, the objective of our study was to quantify and analyse the spread of H. axyridis in its early stages of invasion in Great Britain. Our data shows that between 2004 and 2006, the species spread north through Great Britain at the rate of 58 km year-1 and west at the rate of 144.5 km year-1. In England H. axyridis spread north to Yorkshire and west to Cornwall by the end of 2006, and also reached Wales. Recorded occurrence (of one or more H. axyridis individuals at larval, pupal and/or adult stage) in 10 km squares in Great Britain was: 2004—51; 2005—149; 2006—447. Records of juvenile H. axyridis extend through most of the recorded British range of the species, and we present evidence of bi-voltinism in the population in 2006.  相似文献   

10.
Abstract: The Spanish town of Galve (Teruel) is notable because of the abundance of Upper Jurassic and, especially, Lower Cretaceous vertebrates recorded there. Although most groups have been studied in detail, information on turtles is very limited even though the material is relatively abundant. So far, no turtle taxa have been identified at the generic level. The only Lower Cretaceous articulated specimen from Galve is analysed here. It is identified as a representative of Cryptodira, Galvechelone lopezmartinezae gen. et sp. nov. Galvechelone lopezmartinezae is determined as a taxon belonging to the node that groups the turtles traditionally assigned to ‘Macrobaenidae’ and ‘Sinemydidae’, and other taxa such as the members of Panchelonioidea. This node, very abundant in the Lower Cretaceous of Asia, and with a broad subsequent distribution, has recently been recognized in the Lower Cretaceous of Europe. The diversity of basal members of Eucryptodira in the European Late Jurassic (represented by Thalassemydidae, Plesiochelyidae and Eurysternidae) was high. Owing to a relative scarcity of well‐preserved early Cretaceous turtles from Europe, the knowledge of this group of reptiles is limited. The study of the new turtle from Galve, together with the recently described Hoyasemys jimenezi, and the recently completed review of the enigmatic Chitracephalus dumonii demonstrate that members of the cryptodiran node grouping ‘Macrobaenidae’, ‘Sinemydidae’ and Panchelonioidea were also very diverse in this period.  相似文献   

11.
HLA-mismatched natural killer (NK) cells have shown efficacy in acute myeloid leukemia, and their adoptive transfer in patients with other malignancies has been proven safe. This phase I clinical trial was designed to evaluate safety (primary endpoint) and possible clinical efficacy (secondary endpoint) of repetitive administrations of allogeneic, in vitro activated and expanded NK cells along with chemotherapy in patients with advanced non-small cell lung cancer (NSCLC). Patients with unresectable, locally advanced/metastatic NSCLC receiving 1st/2nd line chemotherapy were eligible to receive 2–4 doses of activated NK cells from two relative donors. Donor’s CD56+ cells were cultured for 20–23 days with interleukin-15 (IL-15) and hydrocortisone (HC) and administered intravenously between chemotherapy cycles. Premedication with corticosteroids and/or H1 inhibitors was allowed. Sixteen patients (performance status 0–1) with adenocarcinoma (n = 13) or squamous cell carcinoma (n = 3) at stage IIIb (n = 5) or IV (n = 11) receiving 1st (n = 13) or 2nd (n = 3) line treatment were enrolled. Fifteen patients received 2–4 doses of allogeneic activated NK cells (0.2–29 × 106/kg/dose, median 4.15 × 106/kg/dose). No side effects (local or systemic) were observed. At a median 22-month follow-up (range, 16.5–26 months) 2 patients with partial response and 6 patients with disease stabilization were recorded. Median progression free survival and overall survival were 5.5 and 15 months, respectively. A 56% 1-year survival and a 19% 2-year survival were recorded. In conclusion, repetitive infusions of allogeneic, in vitro activated and expanded with IL-15/HC NK cells, in combination with chemotherapy are safe and potentially clinically effective.  相似文献   

12.
Introduced predators have become major threats to native animal species in oceanic islands. A number of studies have shown that alien predators have caused serious extinctions of island endemics. However, little attention has been paid to the evolutionary impacts of alien predators on native species. The present study shows that predation by black rats, Rattus rattus, has resulted in ecological and morphological changes in the land snail Mandarina anijimana from the island of Anijima in the Ogasawara archipelago. The frequency of empty predated shells has increased over the past 17–19 years in southern areas of the island. The shells of these snails were found to be significantly higher, smaller and darker in the survey in 2006 than in the survey in 1987–1989 performed in central and southern parts of Anijima, where predation by Rattus was serious. M. anijimana were formerly restricted to shallow broad-leaved litter, whereas they are currently found in deep palm litter, where predation pressure from Rattus may be lower. This suggests that increased predation pressure by Rattus has changed the habitat use of M. anijimana. The close association between shell morphology and habitat use of Mandarina species suggests that the habitat shift induced by the predation of Rattus has caused these changes in the shell morphology of M. anijimana over a period of 17–19 years.  相似文献   

13.
The extrachromosome 5A of shallot (Allium cepa L., genomes AA) has an important role in flavonoid biosynthesis in the scaly leaf of Allium fistulosum–shallot monosomic addition lines (FF+nA). This study deals with the production and biochemical characterisation of A. fistulosum–shallot multiple alien addition lines carrying at least 5A to determine the chromosomal locations of genes for quercetin formation. The multiple alien additions were selected from the crossing between allotriploid FFA (♀) and A. fistulosum (♂). The 113 plants obtained from this cross were analysed by a chromosome 5A-specific PGI isozyme marker of shallot. Thirty plants were preliminarily selected for an alien addition carrying 5A. The chromosome numbers of the 30 plants varied from 18 to 23. The other extrachromosomes in 19 plants were completely identified by using seven other chromosome markers of shallot. High-performance liquid chromatography analyses of the 19 multiple additions were conducted to identify the flavonoid compounds produced in the scaly leaves. Direct comparisons between the chromosomal constitution and the flavonoid contents of the multiple alien additions revealed that a flavonoid 3′-hydroxylase (F3′H) gene for the synthesis of quercetin from kaempferol was located on 7A and that an anonymous gene involved in the glucosidation of quercetin was on 3A or 4A. As a result of supplemental SCAR analyses by using genomic DNAs from two complete sets of A. fistulosum–shallot monosomic additions, we have assigned F3′H to 7A and flavonol synthase to 4A.  相似文献   

14.
The multisite phosphorylation-dephosphorylation cycle is a motif repeatedly used in cell signaling. This motif itself can generate a variety of dynamic behaviors like bistability and ultrasensitivity without direct positive feedbacks. In this paper, we study the number of positive steady states of a general multisite phosphorylation–dephosphorylation cycle, and how the number of positive steady states varies by changing the biological parameters. We show analytically that (1) for some parameter ranges, there are at least n + 1 (if n is even) or n (if n is odd) steady states; (2) there never are more than 2n − 1 steady states (in particular, this implies that for n = 2, including single levels of MAPK cascades, there are at most three steady states); (3) for parameters near the standard Michaelis–Menten quasi-steady state conditions, there are at most n + 1 steady states; and (4) for parameters far from the standard Michaelis–Menten quasi-steady state conditions, there is at most one steady state.   相似文献   

15.
To produce alien monosomic addition lines (AMALs) of Allium cepa (genomes CC, 2n = 2x = 16) carrying extrachromosomes from Allium roylei (RR, 2n = 2x = 16), reciprocal backcrossing of allotriploids (2n = 24, CCR) with diploids (2n = 16, CC) and selfing of a single allotriploid were carried out. The chromosome numbers in the BC2F1 and BC1F2 progenies ranged from 16 to 32. Forty-eight plants were recorded to possess 2n = 17 among a total of 169 plants in observation. Through the analyses of isozymes, expressed sequence tag (EST) markers, and karyotypes, all eight possible types of A. cepaA. roylei monosomic addition lines (CC+1R–CC+8R) could be identified. Seven types of representative AMALs (without CC+2R) were used for the GISH analysis of somatic chromosomes. Except for CC+6R, all AMALs showed an entire (unrecombined) extrachromosome from A. roylei in the integral diploid background of A. cepa. A single recombination between A. cepa and A. roylei was observed on the extrachromosome in the remaining type. All alloplasmic AMALs possessing A. roylei cytoplasm showed high or complete pollen sterility. Only the autoplasmic CC+4R with A. cepa cytoplasm possessed relatively high pollen fertility. The bulbs of CC+4R displayed the distinct ovoid shape that discriminates them from spherical or oval ones in other AMALs. Downy mildew screening in the field showed higher resistance in A. roylei, a hypo-allotriploid (CCR-nR, 2n = 23), and an allotriploid (CCR, 2n = 24). Meanwhile, no complete resistance was found in some AMALs examined. This was the first trial toward the establishment of a complete set of A. cepaA. roylei monosomic additions.  相似文献   

16.
Aim Conifers are invasive species in many parts of the world, especially in the Southern Hemisphere. There are many introduced conifers in Europe, but their status as alien species is poorly documented. We conducted a comprehensive literature review to ascertain the extent to which alien conifers can be considered invasive. Location Europe. Methods We reviewed the historical record of alien conifer invasion in Europe (i.e. species with a native range outside the continental boundaries of Europe) by screening the DAISIE database and the ISI Web of Science. Results According to DAISIE, there are 54 alien conifer species in Europe. Pseudotsuga menziesii is the species recorded as naturalized in the most countries (12) and the UK is the country with the most naturalized species (18). Thirty‐seven of these conifers have been studied, to some extent, in a total of 131 papers (212 records). Nevertheless, only a few papers have investigated aspects related to biological invasions. In fact, the species are not referred to as alien by the authors in more than half of the papers (66%). Twenty‐five per cent of the papers have investigated plant traits, 46% are about biotic and abiotic factors influencing tree performance and 29% deal with ecological and economic impacts. Most papers are related to entomology, dealing with natural enemies affecting the alien conifers. Main conclusions Scientists have not yet perceived alien conifers in Europe as problematic species. Moreover, the low introduction effort, long lag‐time since plantation and phylogenetic closeness between alien and native conifers are possible reasons for their low expansion in Europe to date. From a management point of view, careful observations of sites with alien conifers is necessary to watch for new invasions. From a scientific perspective, thorough analyses of the extent that introduction, rates of naturalization and biogeographical differences influence invasive spread between the two hemispheres will prove timely.  相似文献   

17.
Although the velocity of single kinesin motors against an opposing force F of 0–10 pN is well known, the behavior of multiple kinesin motors working to overcome a larger load is still poorly understood. We have carried out gliding assays in which 3–7 Drosophila kinesin-1 motors moved a microtubule at 200–700 μm/s against a 0–31 pN load at saturating [ATP]. The load F was generated by applying a spatially uniform magnetic field gradient to a superparamagnetic bead attached to the (+) end of the microtubule. When F was scaled by the average number of motors 〈n〉, the force–velocity relationship for multiple motors was similar to the force–velocity relationship for a single motor, supporting a minimal load-sharing model. The velocity distribution at low load has a single mode consistent with rapid fluctuations of n. However, against a load of 2.5–4.7 pN/motor, additional modes appeared at lower velocity. These observations support the Klumpp–Lipowsky model of multimotor transport [Proc Natl Acad Sci USA 102. 17284–17289 (2005)].  相似文献   

18.
A survey of the fauna of hydrobioid gastropods living in ancient Lake Poso in Sulawesi revealed a total of 16 species, 14 of them new, belonging to two genera, Sulawesidrobia and Keindahan gen. nov. Most species occurred on hard substrates, water plants or rootlets of trees. Since only the upper 0.5 m of the lake have been sampled, many more species probably remain to be discovered. Already, Lake Posoȁ9s fauna ranks among the four most diverse hydrobioid lake faunas worldwide. The Sulawesi lakes including Lake Poso and the Malili Lakes are the only lakes where sizeable radiations of hydrobioid and cerithioid gastropods coexist. Outside Lake Poso, hydrobioid gastropods have not been investigated so far apart from a single species reported from Lake Lindoe similar to or identical with S. bonnei [Abbott, 1945. Occasional Papers on Mollusks 1: 1–4], which has its type locality in Lake Poso and may in fact be a complex of species. Therefore endemicity in Lake Poso cannot be estimated nor is it possible to say, whether the radiation is of lacustrine origin. The introduction of alien fish has had a severe impact on the native fish fauna. The impact on the invertebrate fauna is not known but chances are that this survey based on collections from 1991 no longer reflects the original assemblage in the lake.  相似文献   

19.
Gerres microphthalmus sp. nov., described on the basis of the holotype and 38 paratypes, has a limited distribution in Japan, including Tanega Island, southeastern Kyushu, southern Shikoku, and southern Kii Peninsula, central Honshu. It has not been recorded from the Ryukyu Islands. The species is the fourth member of the “G. filamentosus complex,” characterized by an elongated second dorsal fin spine, the others being G. filamentosus, G. infasciatus, and G. macracanthus. Gerres microphthalmus sp. nov. is most similar to G. filamentosus in overall body appearance, but differs from the latter in having smaller eyes (8%–11% of standard length vs. 10%–16% in the latter), a higher orbit diameter ratio (as % of snout length) (93%–143% of snout vs. 71%–104% of snout), and fewer pored lateral line scales (40–43 vs. 43–46). The limited distribution pattern of the new species is discussed with G. equulus and Lates japonicus (Centropomidae) having a limited distribution similar to that of the new species. Received: June 28, 2001 / Revised: November 13, 2001 / Accepted: December 10, 2001  相似文献   

20.
Germany is situated on the western border of the distribution area of moose (Alces alces) in Europe. In the past, the number of moose sightings has been very limited and irregular in the state of Bavaria (SE Germany). Nearby populations of moose are located in neighboring countries to the east of Germany, in the Czech Republic, and Poland. A monitoring system for moose was established following a considerable increase in moose observations in Bavaria in 2007. As no reproduction has yet been recorded, moose observation has so far been attributed only to migrating individuals. Cows are more often registered than bulls (27 of 35 observations between 2004 and 2008). The reasons for the increase in migratory activities of moose have not yet been identified.  相似文献   

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