Search USGS⌕ Search

SEARCH · Search USGS

Results for “Technology”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 271 records · Page 15Linked to original sources
USGS2021

Field trials to test new trap technologies for monitoring Culex populations and the efficacy of the biopesticide formulation VectoMax® FG for control of larval Culex quinquefasciatus in the Alaka'i Plateau, Kaua'i, Hawaii

Mosquito-borne avian malaria Plasmodium relictum is a key limiting factor for endemic Hawaiian forest birds. In the past decade, populations of Kaua‘i’s endemic forest birds have been in a steep decline due to an increase in malaria transmission. To evaluate the use of available biopesticides for short-term mosquito control we tested the efficacy of the biopesticide VectoMax® FG against Culex quinquefasciatus larvae in naturally occurring perched stream pools, seeps, and ground pools in forest bird habitat in Kaua‘i’s remote Alaka‘i Plateau. We also tested the efficacy of conventional and newer traps and attractants for the capture of adult Culex quinquefasciatus in Hawaiian rain forests and monitored adult mosquito populations at the Kaua‘i field site. During field trials conducted on Hawai‘i Island we captured more Culex quinquefasciatus in gravid traps than in host-seeking traps. Among the host-seeking traps, Biogents BG-Sentinel 2 traps baited with CO2 and BG-Lure caught more Culex quinquefasciatus and Aedes japonicus japonicus than CDC (Centers for Disease Control and Prevention) traps baited with compressed CO2, CDC traps baited with dry ice, or Biogents BG-Sentinel 2 traps baited with BG-Lure and octenol but not CO2. Both Biogents BG-Sentinel 2 and CDC miniature traps baited with compressed CO2 or dry ice captured significantly more Culex quinquefasciatus than Biogents BG-Sentinel 2 traps baited with octenol and BG-Lure but without CO2. We also found that gravid traps baited with timothy hay infusions caught significantly more Culex quinquefasciatus than traps baited with either a commercial gravid mosquito attractant or an infusion made with pelleted rabbit feed. Traps baited with an infusion of timothy hay and donkey dung were the most effective for Culex quinquefasciatus. On Kaua‘i, we operated Biogents BG-Sentinel 2 traps baited with CO2 and gravid traps and captured 29 mosquitoes in 182 trap-nights from October–November 2016 and 126 mosquitoes in 254 trap-nights from September–October 2017. Contrary to our findings on Hawai‘i Island, most mosquitoes (96%) were captured in Biogents BG-Sentinel 2 traps indicating considerable site-to-site variability in trap efficacy. Weekly adult trapping on Kaua‘i indicates Culex quinquefasciatus populations peaked in October but provided no reliable evidence that larval control had any significant effect on adult populations. Overall, VectoMax® FG was very effective at larval control reducing larval abundance by 95% at 48 hours and out to 1-week post-treatment. Treatment was most effective (100% at 1-week post-treatment) in perched pools when early instar larvae were present and least effective in seeps when pupae and fourth instar larvae were most common. Although post-treatment counts fluctuated dramatically, we observed no evidence of population level impacts to the two most common non-target invertebrates: the water strider Microvelia vagans and endemic damselfly naiads (Megalagrion sp.). VectoMax® FG appears to be an effective and safe biopesticide for the local control of Culex quinquefasciatus larvae in forest bird habitat in the Alaka‘i Plateau. Further studies will be necessary to determine if local larval control significantly reduces adult mosquito abundance and, ultimately, avian malaria transmission, and if there are long term, non-target effects associated with repeated use of VectoMax® FG in natural Hawaiian waterways.

Hawaii↗
USGS1912

Report of the Hawaiian Volcano Observatory of the Massachusetts Institute of Technology and the Hawaiian Volcano Research Association

The First Report of the Hawaiian Volcano Observatory is a collection of nine papers. The first provides details of the founding of the Observatory and the second reviews Kīlauea volcanic activity between 1909 and 1911. The next two papers detail the work of the Observatory by Frank Perret and E.S. Shepherd, who both arrived at Kīlauea in the summer of 1911. The third paper focuses on Perret's observations of the eruption within Halema'uma'u, a crater within Kīlauea summit caldera, and includes six weekly articles he wrote for local newspapers. The fourth paper is an account of the first successful attempt to measure the temperature of lava in Halema'uma'u. The next three papers are summaries of Halema'uma'u activity spanning the time after Frank Perret left in the Fall of 1911 to April 3, 1912. The last two papers are brief reports on Mauna Loa.

Report of the Hawaiian Volcano Observatory↗
USGS1917

Second report of the Hawaiian Volcano Observatory of the Massachusetts Institute of Technology and the Hawaiian Volcano Research Association: On cyclical variations in eruption at Kilauea

This work treats chiefly of observed changes in the height of stand of molten lava in the crater of Kilauea. It also takes account of concurrent variations in the apparent energy of eruptive action at the surface of the magma column. With little doubt these conditions vary in a complex periodic way. To explain these periods in part an hypothesis is advanced which depends upon recurrent astronomical changes. It would be exceedingly difficult to develop this in any thorough dynamical way. Yet it is doubtful if any other treatment could serve quite adequately. Obviously the form given it in this study is crude. In ordinary language it is not easy to state the idea precisely, so as to differentiate the exact action hypothesized from action of a similar and familiar kind. Consequently such a presentation of the hypothesis as this is susceptible of erroneous comprehension. Besides, through incompleteness, this non-mathematical statement of it may be wrong in certain aspects or details. Therefore this paper must be read guardedly and with close attention.

Hawaii↗