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Reproductive ecology of the mudskipper Boleophthalmus pectinirostris 被引量:2
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作者 HONG Wanshu CHEN Shixi +1 位作者 ZHANG Qiyong WANG Qiong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2007年第4期72-81,共10页
The reproductive ecology of the mudskipper Boleophthalmus pectinirostris was investigated during the spawning season in the Funing Bay, Fujian, China. The fish burrows were basically Y-shaped and had two openings onto... The reproductive ecology of the mudskipper Boleophthalmus pectinirostris was investigated during the spawning season in the Funing Bay, Fujian, China. The fish burrows were basically Y-shaped and had two openings onto the mudflats. Part of the intersection at the center of the burrow was dilated to form a "spawning chamber". The dissolved oxygen concentrations ( 0.40 ~ 0.65 mg/dm^3) of water 15 cm deep inside the burrows were much lower than those (5.96 ~ 6.19 mg/dm^3) of intertidal pool water. Water temperatures inside the burrows were much lower than those of intertidal pools. Field investigations indicated that eggs were laid on the inner wall and ceiling of the spawning chamber by means of filamentous attachments, and a male stayed inside the burrows to guard it. Field investigations also suggested that fish of both sexes constructed mud burrows by themselves but that the spawning chamber was made only in the male burrow. The male attracted a female to his burrow for mating and spawning. There was no water in the spawning chamber, and thus the eggs were exposed to the air in the chamber. Changes in spawning readiness and gunadosomatic index indicated that synchronization of spawning was related to the semi-lunar periodicity, and this is the first report of this relationship in the mudskippers. 展开更多
关键词 Boleophthalmus pectinirostris reproductive ecology burrow fish
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Reproductive ecology of the black rat (Rattus rattus) in Madagascar: the influence of density-dependent and -independent effects 被引量:1
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作者 Kathryn SCOBIE Soanandrasana RAHELINIRINA +7 位作者 Voahangy SOARIMALALA Fehivola Mandanirina ANDRIAMIARIMANANA Corinne RAHAINGOSOAMAMITIANA Toky RANDRIAMORIA Soloandry RAHAJANDRAIBE Xavier LAMBIN Minoarisoa RAJERISON Sandra TELFER 《Integrative Zoology》 SCIE CSCD 2024年第1期66-86,共21页
The black rat(Rattus rattus)poses a severe threat to food security and public health in Madagascar,where it is a major cause of pre-and post-harvest crop losses and an important reservoir for many zoonotic diseases,in... The black rat(Rattus rattus)poses a severe threat to food security and public health in Madagascar,where it is a major cause of pre-and post-harvest crop losses and an important reservoir for many zoonotic diseases,including plague.Elsewhere,ecologically based rodent management(EBRM)strategies have been developed using ecologi-cal information to inform decisions on where and when to target control.EBRM could deliver improved health and well-being outcomes in Madagascar if adapted to the local ecological context.Using data collected from removal studies,we explored spatio-temporal patterns in the breeding activity of the black rat(R.rattus)in domestic and agricultural habitats across Madagascar and investigated to what extent these trends are influenced by rainfall and rat density.We identified clear spatio-temporal variation in the seasonality of R.rattus reproduction.Reproduction was highly seasonal both inside and outside of houses,but seasonal trends varied between these two habitats.Sea-sonal trends were explained,in part,by variation in rainfall;however,the effect of rainfall on reproductive rates did itself vary by season and habitat type.A decline in breeding intensity with increasing rat density was recorded outside of houses.This has important implications for control,as populations may compensate for removal through increased reproduction.We recommend that sustained control initiated before the main breeding season,combined with improved hygiene and adequate rodent-proofing in homes and grain stores,could curtail population growth and reduce pre-and post-harvest losses provided that these measures overcome the compensatory response of rodent populations. 展开更多
关键词 Madagascar Rattus rattus reproductive ecology rodent control
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Function of male and hermaphroditic flowers and size-dependent gender diphasy of Lloydia oxycarpa (Liliaceae) from Hengduan Mountains 被引量:4
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作者 Yang Niu Qiangbang Gong +2 位作者 Deli Peng Hang Sun Zhimin Li 《Plant Diversity》 SCIE CAS CSCD 北大核心 2017年第4期187-193,共7页
Although hermaphroditism is common in flowering plants, unisexual flowers occur in many plant taxa,forming various sexual systems. However, the sexual system of some plants is difficult to determine morphologically, g... Although hermaphroditism is common in flowering plants, unisexual flowers occur in many plant taxa,forming various sexual systems. However, the sexual system of some plants is difficult to determine morphologically, given that their sex expression may be influenced by both genetic and environmental factors. Specifically, androdioecy(the coexistence of both male and hermaphroditic individuals in the same population) has often been confused with the gender diphasy, a gender strategy in which plants change their sex expression between seasons. We studied the reproductive function of male and hermaphroditic flowers of Lloydia oxycarpa(Liliaceae), in order to investigate its sexual system and determine whether it is a gender-diphasic species. We found that although male flowers occur in a considerable number of plants, relative to hermaphrodites, they did not exhibit any significant reproductive advantage in terms of flower size, pollen quantity, attractiveness to visitors or siring success. In addition, this plant has spontaneous self-pollination and showed no inbreeding depression. These results render the maintenance of male individuals almost impossible. Furthermore, a considerable number of individuals changed their sex in successive years. The sex expression was found to be related to bulb size and dry weight, with larger individuals producing hermaphroditic flowers and smaller individuals producing male flowers. These results suggest that L. oxycarpa is not an androdioecious plant but represents a rare case of size-dependent gender diphasy. 展开更多
关键词 Gender diphasy Lloydia reproductive ecology Sexual system Size-dependent sex allocation
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Mojave desert tortoise(Gopherus agassizii)thermal ecology and reproductive success along a rainfall cline
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作者 Annette E.SIEG Megan M.GAMBONE +3 位作者 Bryan P.WALLACE Susana CLUSELLATRULLAS James R.SPOTILA Harold W.AVERY 《Integrative Zoology》 SCIE CSCD 2015年第3期282-294,共13页
Desert resource environments(e.g.microclimates,food)are tied to limited,highly localized rainfall regimes which generate microgeographic variation in the life histories of inhabitants.Typically,enhanced growth rates,r... Desert resource environments(e.g.microclimates,food)are tied to limited,highly localized rainfall regimes which generate microgeographic variation in the life histories of inhabitants.Typically,enhanced growth rates,reproduction and survivorship are observed in response to increased resource availability in a variety of desert plants and short-lived animals.We examined the thermal ecology and reproduction of US federally threatened Mojave desert tortoises(Gopherus agassizii),long-lived and large-bodied ectotherms,at opposite ends of a 250-m elevation-related rainfall cline within Ivanpah Valley in the eastern Mojave Desert,California,USA.Biophysical operative environments in both the upper-elevation,“Cima,”and the lower-elevation,“Pumphouse,”plots corresponded with daily and seasonal patterns of incident solar radiation.Cima received 22%more rainfall and contained greater perennial vegetative cover,which conferred 5°C-cooler daytime shaded temperatures.In a monitored average rainfall year,Cima tortoises had longer potential activity periods by up to several hours and greater ephemeral forage.Enhanced resource availability in Cima was associated with larger-bodied females producing larger eggs,while still producing the same number of eggs as Pumphouse females.However,reproductive success was lower in Cima because 90%of eggs were depredated versus 11%in Pumphouse,indicating that predatory interactions produced counter-gradient variation in reproductive success across the rainfall cline.Land-use impacts on deserts(e.g.solar energy generation)are increasing rapidly,and conservation strategies designed to protect and recover threatened desert inhabitants,such as desert tortoises,should incorporate these strong ecosystem-level responses to regional resource variation in assessments of habitat for prospective development and mitigation efforts. 展开更多
关键词 Gopherus agassizii operative environments reproductive ecology resource gradient
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Seasonal change mediates the shift between resource and pollen limitation in Hedysarum scoparium(Fabaceae)
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作者 ChengChen Pan Qi Feng +5 位作者 HaLin Zhao XueYong Zhao LinDe Liu JiLiang Liu Li Zhang Jin Li 《Research in Cold and Arid Regions》 CSCD 2015年第1期94-98,共5页
Theory suggests that with sufficient environmental variation, pollen limitation might be observed at some places or times, and resource limitation at others, but there are no empirical data about the effect of seasona... Theory suggests that with sufficient environmental variation, pollen limitation might be observed at some places or times, and resource limitation at others, but there are no empirical data about the effect of seasonal change on the variation of pollen limitation and resource limitation within a flowering season. In this study, we examined pollen and resource limi- tation by comparing fruit set and seed production in natural- and hand-pollinated Hedysarum scoparium flowers in the middle reaches of the Hexi Corridor region, China, in 2010. We also described a role for the first substantial autumn rainfall in mediating a shift between pollen and resource limitation in H. scoparium, but did not analyze this experimentally Our results indicated that H. scoparium was resource limited at peak flowering during the summer, and was pollen limited at peak flowering during the autumn. The seasonal change (summer to autumn) mediated the shift between pollen and resource limitations in H. scoparium. The shift timing depended on the date of the first autumn rainfall in 2010. Changes in the first substantial rainfall in autumn may affect fruiting of H. scoparium, thus affecting population persistence of this species and development/structure of the local ecosystem if such conditions persist. 展开更多
关键词 plant reproductive ecology fruit set seed production Hedysarum scoparium
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Sea Turtle Nesting: What Is Known and What Are the Challenges under a Changing Climate Scenario
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作者 Raquel A. M. São Miguel Rita Anastácio Mário J. Pereira 《Open Journal of Ecology》 2022年第1期1-35,共35页
The rate of climate change experienced globally in recent decades may compromise sea turtles’ survival;especially temperature increase, which is particularly fast, impacts life history characteristics, such as temper... The rate of climate change experienced globally in recent decades may compromise sea turtles’ survival;especially temperature increase, which is particularly fast, impacts life history characteristics, such as temperature-dependent sex determination (TSD), late maturity and sea turtles highly migratory nature. This review aims to identify and summarize the information that has been collected from 2009-2020 in order to aid future empirical studies that seek to fill these and other knowledge gaps, and subsequently assist conservationists in making multilevel decisions to protect sea turtle populations and species. In a summarized way the general knowledge acquired so far on the influence of environmental abiotic and biotic factors on nesting behaviour and hatching, emergence and survival successes of sea turtle hatchlings, was gathered. To accomplish this work, a search on Web of Science, Science Direct, NCBI/PubMed, and Google Scholar was carried out using the terms “sea turtles + climate change”. Published articles in the period 2009-2020 were selected, related to the nesting ecology of 5 species of sea turtles: <em>Caretta caretta</em>, <em>Eretmochelys imbricata</em>, <em>Dermochelys coriacea</em>,<em> Chelonia mydas</em>, <em>Lepidochelys olivacea</em>. Emphasis was also placed on geographical information and on population location (e.g. climatic conditions during the nesting season). These articles (N = 126) were analysed giving relevance to researcher’s data interpretations, comparisons with other researches, and the reached conclusions. An attempt was made to represent all 5 species of sea turtles when selecting articles on each of the environmental factors that influence sea turtle nesting: temperature, humidity, nesting substrate, gases, depth of the nest, sea surface temperature (SST), nest location on the beach, nesting phenology and geographic distribution of nesting habitats. The interaction between these parameters and their consequences on the terrestrial phase of reproduction are presented and discussed. 展开更多
关键词 reproductive ecology Sea Turtles Climate Change Nesting Phenology and Geographic Distribution of Nesting Habitats
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Effects of nectar-robbing on plant reproduction and evolution
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作者 ZHANG Yanwen WANG Yong GUO Youhao 《Frontiers in Biology》 CSCD 2007年第4期443-449,共7页
The relationship between plant and pollinator is considered as the mutualism because plant benefits from the pollinator’s transport of male gametes and pollinator benefits from plant’s reward.Nectar robbers are freq... The relationship between plant and pollinator is considered as the mutualism because plant benefits from the pollinator’s transport of male gametes and pollinator benefits from plant’s reward.Nectar robbers are frequently described as cheaters in the plant-pollinator mutualism,because it is assumed that they obtain a reward(nectar)without providing a service(pollination).Nectar robbers are birds,insects,or other flower visitors that remove nectar from flowers through a hole pierced or bitten in the corolla.Nectar robbing repre-sents a complex relationship between animals and plants.Whether plants benefit from the relationship is always a con-troversial issue in earlier studies.This paper is a review of the recent literatures on nectar robbing and attempts to acquire an expanded understanding of the ecological and evolutionary roles that robbers play.Understanding the effects of nectar robbers on the plants that they visited and other flower visi-tors is especially important when one considers the high rates of robbing that a plant population may experience and the high percentage of all flower visitors that nectar robbers make to some species.There are two standpoints in explaining why animals forage on flowers and steal nectar in an illegitimate behavior.One is that animals can only get food in illegitimate way because of the mismatch of the morphologies of animals’mouthparts and floral structure.The other point of view argues that nectar robbing is a relatively more efficient,thus more energy-saving way for animals to get nectar from flowers.This is probably associated with the difficulty of changing attitudes that have been held for a long time.In the case of positive effect,the bodies of nectar robbers frequently touch the sex organs of plants during their visiting to the flowers and causing pollination.The neutral effect,nectar robbers’behavior may destruct the corollas of flowers,but they neither touch the sex organs nor destroy the ovules.Their behavior does not affect the fruit sets or seed sets of the hosting plant.Besides the direct impacts on plants,nectar robbers may also have an indirect effect on the behavior of the legitimate pollinators.Under some circumstances,the change in pollinator behavior could result in improved repro-ductive fitness of plants through increased pollen flow and out-crossing. 展开更多
关键词 plant reproductive ecology nectar robbing HOST legitimate pollinator reproductive fitness
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