31 research outputs found

    Using Satellite Tracking to Optimize Protection of Long-Lived Marine Species: Olive Ridley Sea Turtle Conservation in Central Africa

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    Tractable conservation measures for long-lived species require the intersection between protection of biologically relevant life history stages and a socioeconomically feasible setting. To protect breeding adults, we require knowledge of animal movements, how movement relates to political boundaries, and our confidence in spatial analyses of movement. We used satellite tracking and a switching state-space model to determine the internesting movements of olive ridley sea turtles (Lepidochelys olivacea) (n = 18) in Central Africa during two breeding seasons (2007-08, 2008-09). These movements were analyzed in relation to current park boundaries and a proposed transboundary park between Gabon and the Republic of Congo, both created to reduce unintentional bycatch of sea turtles in marine fisheries. We additionally determined confidence intervals surrounding home range calculations. Turtles remained largely within a 30 km radius from the original nesting site before departing for distant foraging grounds. Only 44.6 percent of high-density areas were found within the current park but the proposed transboundary park would incorporate 97.6 percent of high-density areas. Though tagged individuals originated in Gabon, turtles were found in Congolese waters during greater than half of the internesting period (53.7 percent), highlighting the need for international cooperation and offering scientific support for a proposed transboundary park. This is the first comprehensive study on the internesting movements of solitary nesting olive ridley sea turtles, and it suggests the opportunity for tractable conservation measures for female nesting olive ridleys at this and other solitary nesting sites around the world. We draw from our results a framework for cost-effective protection of long-lived species using satellite telemetry as a primary tool

    The peculiar breeding biology of the Amazonian frog Allobates subfolionidificans (Aromobatidae)

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    Allobates subfolionidificans is a vulnerable and endemic leaf-litter frog from the state of Acre, Brazilian Amazonia. We monitored a population of A. subfolionidificans through regular censuses and mark-recapture of 181 individuals during an entire breeding season to characterize its reproductive behavior. The space use of A. subfolionidificans individuals differed between sexes, with males using smaller and more segregated spaces. Males defended territories and were aggressive against same-sex individuals, which was not the case in females. The daily cycle of calling activity showed peaks in the morning and in the afternoon, and the occurrence of reproductive events was positively correlated with monthly rainfall. The breeding behavior comprised vocal and tactile interactions, although the species lacked reproductive amplexus. Egg and larvae attendance, as well as tadpole transport to water environments was performed mostly by males but occasionally by females, probably in cases of desertion by the father. This species is characterized by performing courtship, mating, oviposition, as well as egg and larvae attendance exclusively on the under surface of leaves, a unique behavior among members of the superfamily Dendrobatoidea

    Transmission mode and distribution of parasites among groups of the social lizard Egernia stokesii

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    The original publication is available at www.springerlink.comWe explored patterns of infection of three apicomplexan blood parasites with different transmission mechanisms in 46 social groups across seven populations of the Australian lizard, Egernia stokesii. There was higher aggregation of infections within social groups for Hemolivia, transmitted by ticks, and Schellackia, either tick-transmitted or directly transmitted from mother to offspring, than for Plasmodium, with more mobile dipteran vectors. Prevalence was not related to group size, proximity to other groups or spatial overlap with adjacent groups for any of the parasites. However, for Hemolivia, groups with higher levels of relatedness among adults had higher parasite prevalence. Living in social groups leads to higher risk of infection for parasites with low transmission mobility. An unanswered question is why so few lizard species tolerate these risks to form stable social aggregations.Stephanie S. Godfrey, C. Michael Bull, Kris Murray and Michael G. Gardne

    Targeted expression of redesigned and codon optimised synthetic gene leads to recrystallisation inhibition and reduced electrolyte leakage in spring wheat at sub-zero temperatures

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    Abstract Antifreeze proteins (AFPs) adsorb to ice crystals and inhibit their growth, leading to non-colligative freezing point depression. Crops like spring wheat, that are highly susceptible to frost damage, can potentially be made frost tolerant by expressing AFPs in the cytoplasm and apoplast where ice recrystallisation leads to cellular damage. The protein sequence for HPLC-6 α-helical antifreeze protein fromwinter flounderwas rationally redesigned after removing the prosequences in the native protein. Wheat nuclear gene preferred amino acid codons were used to synthesize a recombinant antifreeze gene, rAFPI. Antifreeze protein was targeted to the apoplast using a Murine leader peptide sequence from the mAb24 light chain or retained in the endoplasmic reticulum using C-terminus KDEL sequence. The coding sequences were placed downstream of the rice Actin promoter and Actin-1 intron and upstream of the nopaline synthase terminator in the plant expression vectors. Transgenic wheat lines were generated through micro projectile bombardment of immature embryos of spring wheat cultivar Seri 82. Levels of antifreeze protein in the transgenic lines without any targeting peptide were low (0.06–0.07%). The apoplast-targeted protein reached a level of 1.61% of total soluble protein, 90% of which was present in the apoplast. ER-retained protein accumulated in the cells at levels up to 0.65% of total soluble proteins. Transgenic wheat line T-8 with apoplast-targetedantifreeze protein exhibited the highest levels of antifreeze activity and provided significant freezing protection even at temperatures as low as −7◦C
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