Turtles on the edge: movement of loggerhead turtles (Caretta caretta) along oceanic fronts, spanning longline fishing grounds in the central North Pacific, 1997–1998     

Jeffrey J. Polovina  Donald R. Kobayashi  Denise M. Parker  Michael P. Seki  & George H. Balazs 《Fisheries Oceanography》2000,9(1):71-82

Nine juvenile loggerhead sea turtles tracked during 1997 and 1998 in the central North Pacific by satellite telemetry all travelled westward, against prevailing currents, along two convergent fronts identified by satellite remotely sensed data on sea surface temperature (SST), chlorophyll and geostrophic currents. These fronts are characterized by gradients in sea surface height that produce an eastward geostrophic current, with gradients in surface chlorophyll and SST. Six of the turtles were associated with a front characterized by 17°C SST, surface chlorophyll of about 0.2 mg m^–3, and eastward geostrophic current of about 4 cm s^–1, while the other three turtles were associated with a front with 20°C SST, surface chlorophyll of about 0.1 mg m^–3, and eastward geostrophic flow of about 7 cm s^–1. These results appear to explain why incidental catch rates of loggerheads in the Hawaii longline fishery are highest when gear is set at 17°C and 20°C, SST. Further, from the seasonal distribution of longline effort relative to these fronts, it appears that the surface longline fishing ground lies largely between these two fronts during the first quarter and well to the south of the 17°C front, but including the 20°C front, in the second quarter. These findings suggest seasonal or area closures of the longline fishery that could be tested to reduce incidental catches of loggerheads. Finally, these results illustrate the insights which can be achieved by combining data on movement of pelagic animals with concurrent remotely sensed environmental data.  相似文献   

Early maritime economy and El Nino events at quebrada tacahuay, peru     

DK Keefer  SD deFrance  ME Moseley  JB Richardson  DR Satterlee  A Day-Lewis 《Science (New York, N.Y.)》1998,281(5384):1833-1835

The archaeological site of Quebrada Tacahuay, Peru, dates to 12,700 to 12,500 calibrated years before the present (10,770 to 10,530 carbon-14 years before the present). It contains some of the oldest evidence of maritime-based economic activity in the New World. Recovered materials include a hearth, lithic cutting tools and flakes, and abundant processed marine fauna, primarily seabirds and fish. Sediments below and above the occupation layer were probably generated by El Nino events, indicating that El Nino was active during the Pleistocene as well as during the early and middle Holocene.  相似文献   

Defence against Bremia lactucae conferred by the resistance gene Dm7 in lettuce is broken by treatment with dichloroisonicotinic acid     

Adriana Oikonomou  Mark H. Bennett  Adam A. H. Parker  Jurriaan Ton  John W. Mansfield 《Plant pathology》2022,71(3):611-620

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Presence and diversity of mixed avian Plasmodium spp. infections in introduced birds whose distribution overlapped with threatened New Zealand endemic birds     

ER Schoener  DM Tompkins  KA Parker  I Castro 《New Zealand veterinary journal》2020,68(2):101-106

ABSTRACT

Aims: To determine the presence of infection and co-infection of Plasmodium lineages in introduced birds at translocation sites for the North Island saddleback (Philesturnus rufusater), to investigate their role as Plasmodium spp. reservoirs.

Methods: Blood samples were collected from introduced bird species, with a special focus on blackbirds (Turdus merula) and song thrushes (Turdus philomelos), at six locations in the North Island of New Zealand that were the origin, or translocation sites, for North Island saddleback. Where available, blood smears were examined, and blood samples were tested using nested PCR with subsequent sequence analysis, for the presence of Plasmodium spp.

Results: Of the 55 samples tested using PCR analysis, 39 (71%) were positive for Plasmodium spp., and 28/40 (62%) blood smears were positive for Plasmodium spp. Overall, 31 blood samples were from blackbirds with 28/31 (90%) samples positive for Plasmodium spp. Six distinct avian Plasmodium lineages were identified, including three cosmopolitan lineages; Plasmodium vaughani SYAT05 was detected in 16 samples, Plasmodium matutinum Linn1 in 10 samples and Plasmodium elongatum GRW6 in eight samples. Mixed infections with more than one lineage were detected in 12 samples. Samples from two Australian magpies (Gymnorhina tibicen) were positive for Plasmodium. sp. lineage MYNA02, previously not identified in New Zealand.

Conclusions and clinical relevance: This is the first report from New Zealand in which specific Plasmodium spp. mixed infections have been found in introduced birds. Co-infections with several cosmopolitan Plasmodium lineages were identified, as well as the first report in New Zealand of an exotic avian Plasmodium sp. lineage, in Australian magpies. Whilst the role of introduced birds in maintaining and spreading pathogenic avian malaria in New Zealand is unclear, there is a potential infection risk to native birds, especially where distributions overlap.  相似文献   

Sublethal effect of Beauveria bassiana on feeding and fecundity of the sunn pest,Eurygaster integriceps Puton (Hemiptera: Scutelleridae)     

A. N. Trissi  M. El‐Bouhssini  M. Skinner  B. L. Parker 《EPPO Bulletin》2019,49(3):570-577

The sunn pest, Eurygaster integriceps Puton, is a major pest of wheat in West and Central Asia. Studies were conducted to investigate the effect of Beauveria bassiana (teleomorph; Cordyceps bassiana) isolates on the sunn pest. Bioassays were done with adult insects collected from overwintering sites at three different times. The effect of sublethal doses of fungi on the insects’ feeding and fecundity was determined. When the sunn pest adults were treated with 2 × 10⁷ conidia mL^?1, all isolates caused significant sunn pest mortality varying between 24 and 100% 12 days after inoculation. There were significant differences between mortality, depending on the date of fungal application. Adult sunn pests treated with B. bassiana at sublethal concentrations caused significantly less damage to wheat leaves than sunn pests in the control. The number of eggs laid by the sunn pest was significantly fewer when wheat plots in plastic greenhouse and field cages were infested with adult sunn pests treated at sublethal concentrations, compared with sunn pests in control plots. Results show that sublethal dosages of B. bassiana reduced sunn pest feeding and fecundity. Applying B. bassiana in sunn pest overwintering sites minimizes the pest populations, which would move to wheat fields in spring.  相似文献   

survival of field-grown rhizobia over the dry summer period in Western Australia     

D.L. Chatel  C.A. Parker 《Soil biology & biochemistry》1973,5(4):415-423

The survival over summer of field-grown root nodule bacteria was studied in the field and the laboratory during the course of an investigation into a nodulation problem of annual clovers. Dry field soils containing Rhizobium trifolii and R. lupini were subjected to a range of temperatures in the laboratory, the bacteria surviving 6 h exposure to temperatures as high as 80°C. Soil temperatures during summer were recorded at different depths. Populations of rhizobia were estimated at these depths from the end of the growing season (October) to early autumn (April) in plots which had carried dense swards of subterranean clover and Serradella. High populations of R. lupini were maintained in the Serradella plots throughout the summer. Populations of R. trifolii in the subterranean clover plots were initially much lower, and declined with both time and depth.The problem known as ‘second-year clover mortality’ is primarily due to low numbers of clover rhizobia in the soil at the end of the growing season. This situation is aggravated over the long hot dry summer, when there is a further decline in numbers.  相似文献   

Action of Penicillin on Streptococci: Enhancement of Sensitivity in vivo?     

Rasch C  Parker RF 《Science (New York, N.Y.)》1952,116(3001):16-17

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The relation between the equivalent acidity of sources of nitrogen and their efficiency in potato fertilization     

F. W. Parker 《American Journal of Potato Research》1935,12(3):60-62

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Evaluation of conjunctival graft procedures and factors that lead to graft complications in canine cases     

Stephanie C. Osinchuk  Shayna Levitt  Lynne Sheila Sandmeyer  Sarah E. Parker 《Veterinary ophthalmology》2023,26(1):53-61

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