Latest Posts

Foraging energetics of Grey-headed Albatrosses Diomedea chrysostoma at Bird Island, South Georgia

first_imgAt‐sea metabolism (CO2 production) and water turnover of six breeding Grey‐headed Albatrosses Diomedea chrysostoma were measured, using the doubly labelled water method, at Bird Island, South Georgia, Mean food consumption (estimated from a water influx rate of 1.01 1 d‐1 and data on dietary composition) was 1200gd‐1 or 50.4 W. At‐sea metabolism (derived from a rate of CO2 production of 3.98 1 h‐1) was 27.7 W, 2.5 times the estimated basal metabolic rate (BMR). On average the birds ingested nearly twice as much food energy as they expended to obtain it. The metabolic rate during flight (estimated from at‐sea metabolism and activity budget data) was 36.3 W (range 34.7–39.0 W) or 3.2 (range 3.0–3.4) times the predicted BMR. This is the lowest cost of flight yet measured, but consistent with the highly developed adaptations for economic flight shown by albatrosses. These results are briefly compared with data for other polar vertebrates (penguins, fur seals) exploiting similar prey.last_img read more

Molecular analysis of geographic patterns of eukaryotic diversity in Antarctic soils

first_imgWe describe the application of molecular biological techniques to estimate eukaryotic diversity (primarily fungi, algae, and protists) in Antarctic soils across a latitudinal and environmental gradient between approximately 60 and 87degreesS. The data were used to (i) test the hypothesis that diversity would decrease with increasing southerly latitude and environmental severity, as is generally claimed for “higher” faunal and plant groups, and (ii) investigate the level of endemicity displayed in different taxonomic groups. Only limited support was obtained for a systematic decrease in diversity with latitude, and then only at the level of a gross comparison between maritime (Antarctic Peninsula/Scotia Arc) and continental Antarctic sites. While the most southerly continental Antarctic site was three to four times less diverse than all maritime sites, there was no evidence for a trend of decreasing diversity across the entire range of the maritime Antarctic (60 to 72degreesS). Rather, we found the reverse pattern, with highest diversity at sites on Alexander Island (ca. 72degreesS), at the southern limit of the maritime Antarctic. The very limited overlap found between the eukaryotic biota of the different study sites, combined with their generally low relatedness to existing sequence databases, indicates a high level of Antarctic site isolation and possibly endemicity, a pattern not consistent with similar studies on other continents.last_img read more

Gametogenesis and gonad mass cycles in thecommon circumpolar Antarctic echinoidSterechinus neumayeri

first_imgPolar conditions (low and stable seawater temperature coupled with highly seasonal primaryproductivity) constrain reproduction in benthic invertebrates. The reproductive cycle of thecommon Antarctic sea urchin Sterechinus neumayeri was investigated at monthly intervals over a2 yr period in relation to seasonality of chlorophyll standing stock and ability to feed. Competence tospawn increased gradually throughout the austral winter to peaks in September to November. Gonadmass varied strongly, both seasonally and among 3 geographically close sites. Spawning occurredbetween October and January at each site, and was strongest in November of both years. Spawningwas not always accompanied by a reduction in gonad mass because of simultaneous feeding anddeposition of nutritive tissue for the forthcoming winter. Spawning was annual but there was alsostrong evidence for longer, multi-year periodicity in reproductive output. Histological analysis indicatedan 18 to 24 mo vitellogenic cycle, with oocytes developing from 20 to 50 μm in the first winter,and from 50 to 120 μm in the second winter. Of total oocyte volume increase (vitellogenesis), 93%occurred within the last 12 mo. Spermatogenesis took 12 mo. S. neumayeri does not feed during theaustral winter, and vitellogenesis is therefore predominantly decoupled from energy intake. Much ofthe cost of reproductive synthesis is met at a time of severe energy limitation.last_img read more

A step-change in the date of sea-ice breakup in western Hudson Bay

first_imgOver the last four decades there has been a trend to earlier summer breakup of the sea ice in western Hudson Bay, Canada. This sea ice is critical for the polar bears that use it for hunting; with the earlier breakup believed to be a factor in the declining health of the regional polar bear population. Analysis of the change to earlier breakup using passive microwave satellite data is problematic due to currently unquantifiable systematic errors between different satellites. Analysis using Canadian sea ice charts from 1971 to 2008 shows that the change to earlier breakup is best represented by a 12 day step. This step occurs between 1988 and 1989 with no significant trend before or after the step. Although not as great as the three-week gradual change suggested by previous studies this change is still significant. An increase in regional south-westerly winds during the first three weeks of June and a corresponding increase in surface temperature are shown to be likely contributing factors to this earlier breakup. It remains to be seen whether these changes in atmospheric circulation might be ascribed to human actions, or simply natural climate variability.last_img read more

Adjustment of pre-moult foraging strategies in Macaroni Penguins Eudyptes chrysolophus according to locality, sex and breeding status

first_imgThe annual moult creates the highest physiological stress during a penguin’s breeding-cycle and is preceded by a period of hyperphagia at sea. Although crucial to individual survival, foraging strategies before moult have been little investigated in keystone marine consumers in the Southern Ocean. The Macaroni Penguin Eudyptes chrysolophus demonstrates how individuals may adjust their foraging strategies during this period in line with constraints such as potential intraspecific competition between localities, foraging ability between dimorphic sexes and timing at sea between breeding and non-breeding population components. We recorded pre-moult behaviour at sea for 22 Macaroni Penguins from Crozet and Kerguelen Islands (southern Indian Ocean) during 2009 and 2011, using light-based geolocation and stable isotope analysis. Penguins were distributed in population-specific oceanic areas with similar surface temperatures (3.5 °C) south of the archipelagos, where they foraged at comparable trophic levels based on stable isotopes of their blood. Bayesian ‘broken stick’ modelling with concurrent analysis of seawater temperature records from the animal-borne devices showed that within each population, females remained 6 days longer than males in the colder waters before heading back towards their colonies. Finally, 17 other non-breeding individuals that moulted earlier had a higher mean blood δ15N value than did post-breeding birds, meaning that early moulters probably fed more on fish than did late moulters. Our findings of such adjustments in foraging strategies developed across locality, sex and breeding status help understanding of the species’ contrasted pre-moult biology across its range and its ecology in the non-breeding period.last_img read more

Preliminary description of tardigrade species diversity and distribution pattern around coastal Syowa Station and inland Sør Rondane Mountains, Dronning Maud Land, East Antarctica.

first_imgTardigrades are important members of the simple terrestrial ecosystems in the extreme environments in Antarctica. This study provides a baseline description of tardigrade species diversity and distribution pattern within the terrestrial and lake environments of the coastal regions around Syowa Station and the neighbouring inland Sør Rondane Mountains, Dronning Maud Land. We combined data obtained from new and previously described collections and updated data available in the existing literature. We recorded five tardigrade species, three of which (Echiniscus pseudowendti Dastych 1984, Hebesuncus ryani Dastych and Harris 1994, Pseudechiniscus sp.) have not previously been reported from the area, increasing the total recorded tardigrade diversity for this region of continental Antarctica to ten species. The results of our study indicate that tardigrades have been and are major components of the lake environment community in continental Antarctica, with Acutuncus antarcticus (Richters 1904) the most common and dominant species. Our data confirm that the tardigrade species diversity in the vicinity of Syowa Station is very low and suggest potential relationships between individual tardigrade species and terrestrial moss species and depth in freshwater ecosystems.last_img read more

Respiration rates and active carbon flux of mesopelagic fishes (Family Myctophidae) in the Scotia Sea, Southern Ocean

first_imgMesopelagic fish have recently been highlighted as an important, but poorly studied component of marine ecosystems, particularly regarding their role in the marine pelagic food webs and biogeochemical cycles. Myctophids (Family Myctophidae) are one of the most biomass-dominant groups of mesopelagic fishes, and their large vertical migrations provide means of rapid transfer of carbon to the deep ocean where it can be sequestered for centuries or more. In this study, we develop a simple regression for the respiration rate of myctophid fish using literature-based wet mass and habitat temperature data. We apply this regression to net haul data collected across the Scotia-Weddell sector of the Southern Ocean to estimate respiration rates of the biomass-dominant myctophid species. Electrona carlsbergi, Electrona antarctica, and Gymnoscopelus braueri made a high contribution (up to 85%) to total myctophid respiration. Despite the lower temperatures of the southern Scotia Sea (-1.46 to 0.95°C), total respiration here was as high (reaching 1.1 mg C m-2 d-1) as in the warmer waters of the mid and northern Scotia Sea. The maximum respiratory carbon flux of the vertically migrating community was 0.05 to 0.28 mg C m-2 d-1, equivalent to up to 47% of the gravitational particulate organic carbon flux in some parts of the Scotia-Weddell region. Our study provides the first baseline estimates of respiration rates and carbon flux of myctophids in the Southern Ocean. However, direct measurements of myctophid respiration, and of mesopelagic fish generally, are needed to constrain these estimates further and incorporate these fluxes into carbon budgets.last_img read more

SUU Men’s Golf Leads the Way Through 18 Holes at Big Sky Tournament

first_img Brad James FacebookTwitterLinkedInEmailBOULDER CITY, Nev.-Friday, the Big Sky Conference men’s golf tournament commenced with both Southern Utah and Weber State having magnificent performances.The Thunderbirds lead through the first 18 holes at 285 (-3) and the Wildcats are in third at 295 (+7).By virtue of the stellar performance of overall leader Fidel Concepcion (67, -5), Southern Utah is in this position. Furthermore, his teammate, Jake Vincent (70, -2) is tied for sixth and Ali Hameed (72, E) checks in for 9th to keep the Thunderbirds in good shape entering Day 2 of competition.The Wildcats are led by Alex Herzog, who is tied for sixth (71, -1) and Kyler Dearden who is tied for 9th  (72, E).The tournament resumes Saturday. April 28, 2018 /Sports News – Local, Uncategorized SUU Men’s Golf Leads the Way Through 18 Holes at Big Sky Tournament Written by Tags: Alex Herzog/Ali Hameed/Big Sky/Fidel Concepcion/Jake Vincent/Kyler Dearden/Men’s Golf/Southern Utah/Weber Statelast_img read more

Argentina cancels friendly soccer match in Israel

first_img Written by FacebookTwitterLinkedInEmailAlex Caparros/Getty Images(TEL AVIV, Israel) — Argentina’s national soccer team has pulled out of an exhibition match with Israel scheduled for this weekend in Jerusalem, but Israel’s minister of culture and sport said it was in response to security threats against the team’s star rather than political pressure from Palestinian groups.“The game was canceled for one reason only: threats to the life of the star Messi,” Miri Regev said Wednesday night at a press conference in Tel Aviv, referencing Argentine team captain Lionel Messi.“The terror threats against him and his family overwhelmed the world soccer star,” Regev added.On Thursday, Reuters reported that Israel had demanded that soccer’s governing body, FIFA, investigate the threats against Messi and his family.But Saturday’s match, which was sold out, is off. Fans had been clamoring to see Messi play in West Jerusalem’s Teddy Kollek Stadium. Argentina’s soccer federation canceled the game Tuesday, and on Wednesday, apologized to those who had bought tickets.“Unfortunately, we cannot come to Israel in the current situation,” Claudio Tapia, the president of the federation, said at a press conference in Barcelona, where the team has been training ahead of the World Cup.“It’s nothing against the Israeli community, it’s nothing against the Jewish community,” Tapia said. He added that he hoped “everyone will take this decision as a contribution to peace.”Tapia added that he had to prioritize the safety and health of his team ahead of the start of next week’s tournament.The exhibition game was initially scheduled to be played in Haifa, in the north of Israel, but last month was moved to Jerusalem, a move pushed by the culture minister, Regev. But it wasn’t about the location or politics, she said.“It’s not Jerusalem or Haifa,” Regev said at the same press conference. “It’s not BDS [Boycott, Divestment, Sanctions movement]. These are real threats.”“The Argentinians never objected to holding the match in Jerusalem,” she added. “It was even borne of Messi’s will to visit Jerusalem, kiss the Western Wall, and make it to the Church of the Holy Sepulcher.”The Palestinian Football Association opposed the game from the start, and blamed Regev for the move to Jerusalem and what they called the ensuing “disaster.”Messi is wildly popular in the occupied Palestinian territories and in Gaza, where kids parade around in his jerseys like so many other places in the world. The match was hotly opposed by Palestinians, and a pro-Palestinian group protested outside of the Barcelona practice facility earlier this week.Palestinian Football Association president Jibril Rajoub penned a letter, obtained by Israeli newspaper Haaretz and others, to the Argentine Football Association last week, encouraging the team to call off the game.On Wednesday, Rajoub thanked the Argentines for “following their conscience.” Rajoub spoke at a press conference in the West Bank city of Ramallah next to a picture of himself and Messi with the caption “From Palestine, thank you Messi.”“I think Messi and the rest of the Argentine team players respected their principles, and I thank them. They followed their conscience. Messi would have been the first to lose if the game had taken place,” Rajoub said.He added: “Miri Regev is responsible for this disaster if that’s what you’re calling it. Stop supporting the racist, fascist regime led by Miri Regev and Bibi [Prime Minister Benjamin Netanyahu]. I was hoping that the Israeli side would keep politics away from sports. So I’m saying to the Israeli Right and to Regev: This is what you deserve.”For her part, Regev responded: “I say, this was no disaster. We’ll continue hosting international events and won’t let this prevent us from showing pride and happiness in our country.”Copyright © 2018, ABC Radio. All rights reserved. June 7, 2018 /Sports News – National Argentina cancels friendly soccer match in Israelcenter_img Beau Lundlast_img read more

Weber State Football Names Team Captains for 2018

first_img FacebookTwitterLinkedInEmailOGDEN, Utah-Thursday, Weber State football announced its team captains for 2018.They include four seniors in tailback Treshawn Garrett, fullback Brady May, offensive lineman Iosua Opeta and linebacker LeGrand Toia. The only junior captain is defensive end Jonah Williams.Garrett, a Palmdale, Calif. product earned All-Big Sky third team honors last season and has run for 1,791 yards and 16 touchdowns in his career for the Wildcats.May, a native of Heyburn, Idaho, earned first-team All-American and All-Big Sky honors for his special teams contributions and is both a preseason All-Big Sky and All-American selection.Opeta, a Stansbury Park, Utah product, earned first-team All-American honors in 2017 and started 14 games for the Wildcats. He is a preseason All-American.Toia, a senior linebacker out of Riverton, Utah is the only returning captain on the roster. He became an All-American in 2017 after posting 79 tackles (6.1 per game) and was second on the team in sacks. He is a preseason All-Big Sky and All-American selection.Williams, a Meridian, Idaho product, earned all-Big Sky honors last season and was 10th in the conference with 5.5 sacks. He is a preseason all-Big Sky selection. Written by August 23, 2018 /Sports News – Local Weber State Football Names Team Captains for 2018 Tags: Brady May/Iosua Opeta/Jonah Williams/LeGrand Toia/team captains/Treshawn Garrett/Weber State Football Brad Jameslast_img read more